File utils.ts
has 703 lines of code (exceeds 250 allowed). Consider refactoring. Open
import * as d3Array from 'd3-array';
import * as d3Scale from 'd3-scale';
const d3 = {
...d3Array,
...d3Scale,
Function deepClone
has a Cognitive Complexity of 37 (exceeds 5 allowed). Consider refactoring. Open
var deepClone = (function () {
// clone objects, skip other types.
function clone(target) {
if (typeof target == 'object') {
- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Function deepClone
has 136 lines of code (exceeds 25 allowed). Consider refactoring. Open
var deepClone = (function () {
// clone objects, skip other types.
function clone(target) {
if (typeof target == 'object') {
Function template
has 42 lines of code (exceeds 25 allowed). Consider refactoring. Open
export function template(text: string, settings?, oldSettings?): (data?) => string {
if (!settings && oldSettings) {
settings = oldSettings;
}
settings = defaults({}, settings, templateSettings);
Function generateRatioFunction
has 42 lines of code (exceeds 25 allowed). Consider refactoring. Open
export function generateRatioFunction(dimPropName: string, paramsList: string[], chartInstanceRef: Plot) {
var unify = (v) => isDate(v) ? v.getTime() : v;
var dataNewSnap = 0;
Function niceZeroBased
has 42 lines of code (exceeds 25 allowed). Consider refactoring. Open
export function niceZeroBased(domain: number[]) {
var m = 10;
var low = parseFloat(Math.min(...domain).toFixed(15));
Function xml
has 37 lines of code (exceeds 25 allowed). Consider refactoring. Open
export function xml(tag: string) {
var childrenArgIndex = 2;
var attrs = arguments[1];
if (typeof arguments[1] !== 'object' || Array.isArray(arguments[1])) {
childrenArgIndex = 1;
Function niceZeroBased
has a Cognitive Complexity of 11 (exceeds 5 allowed). Consider refactoring. Open
export function niceZeroBased(domain: number[]) {
var m = 10;
var low = parseFloat(Math.min(...domain).toFixed(15));
- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Function defaults
has a Cognitive Complexity of 9 (exceeds 5 allowed). Consider refactoring. Open
export function defaults<T>(obj: T, ...defaultObjs: T[]): T {
var length = defaultObjs.length;
if (length === 0 || !obj) {
return obj;
}
- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Function xml
has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring. Open
export function xml(tag: string) {
var childrenArgIndex = 2;
var attrs = arguments[1];
if (typeof arguments[1] !== 'object' || Array.isArray(arguments[1])) {
childrenArgIndex = 1;
- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Similar blocks of code found in 2 locations. Consider refactoring. Open
export function traverseSpec(
root: Unit,
enterFn: (node: Unit, level?: number) => any,
exitFn: (node: Unit, level?: number) => any,
level = 0
- Read upRead up
Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 66.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
Similar blocks of code found in 2 locations. Consider refactoring. Open
if (top > 0) {
var koeffTop = (deltaTop >= limit) ? -deltaTop : 0;
extent[1] = extent[1] + koeffTop;
}
- Read upRead up
Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 49.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
Similar blocks of code found in 2 locations. Consider refactoring. Open
if (low < 0) {
var koeffLow = (deltaLow >= limit) ? -deltaLow : 0;
extent[0] = (extent[0] - koeffLow);
}
- Read upRead up
Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 49.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
Don't use 'Object' as a type. Avoid using the Object
type. Did you mean object
? Open
export function pick(object: Object, ...props: string[]): Object {
- Read upRead up
- Exclude checks
Rule: ban-types
Bans specific types from being used. Does not ban the corresponding runtime objects from being used.
Notes
- TypeScript Only
Config
A list of ["regex", "optional explanation here"]
, which bans
types that match regex
Examples
"ban-types": true,Object,Use {} instead.,String
Schema
{
"type": "list",
"listType": {
"type": "array",
"items": {
"type": "string"
},
"minLength": 1,
"maxLength": 2
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var span = (+top - +low);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var curr = {e: eventType, ts: Date.now()};
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var diff = ((last.e && (last.e === curr.e)) ? (curr.ts - last.ts) : (limitFromPrev));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Don't use 'Object' as a type. Avoid using the Object
type. Did you mean object
? Open
export function pick(object: Object, ...props: string[]): Object {
- Read upRead up
- Exclude checks
Rule: ban-types
Bans specific types from being used. Does not ban the corresponding runtime objects from being used.
Notes
- TypeScript Only
Config
A list of ["regex", "optional explanation here"]
, which bans
types that match regex
Examples
"ban-types": true,Object,Use {} instead.,String
Schema
{
"type": "list",
"listType": {
"type": "array",
"items": {
"type": "string"
},
"minLength": 1,
"maxLength": 2
}
}
For more information see this page.
Shadowed name: 'deepCopy' Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'source' Open
getCachedResult: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var length = copiedObjects.length;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var err = m / span * step;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var koeffLow = (deltaLow >= limit) ? -deltaLow : 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var pad = 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var direction = angle === 90 ? -1 : 1;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var cachedResult = this.getCachedResult(source);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var key in source) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var noMatch = /(.)^/;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var dataNewSnap = 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var facetSize = varSet.length;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var tickPxSize = (size - (facetSize * pad)) / totalItems;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var hash = {};
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
(<any>deepCopy).register = function (deepCopier) {
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
(<any>deepCopy).register({
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
return (<any>obj) as NextObj<K>;
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
block is empty Open
while (err > correction[++i][0]) {
}// jscs:ignore disallowEmptyBlocks
- Read upRead up
- Exclude checks
Rule: no-empty
Disallows empty blocks.
Blocks with a comment inside are not considered empty.
Rationale
Empty blocks are often indicators of missing code.
Config
If allow-empty-catch
is specified, then catch blocks are allowed to be empty.
If allow-empty-functions
is specified, then function definitions are allowed to be empty.
Examples
"no-empty": true
"no-empty": true,allow-empty-catch
"no-empty": true,allow-empty-functions
"no-empty": true,allow-empty-catch,allow-empty-functions
Schema
{
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"enum": [
"allow-empty-catch"
]
},
{
"type": "string",
"enum": [
"allow-empty-functions"
]
}
]
}
}
For more information see this page.
Shadowed name: 'source' Open
canCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var shouldContinue = enterFn(root, level);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var deepCopier = deepCopiers[i];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var top = parseFloat(Math.max(...domain).toFixed(15));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var frameRequested = false;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var max = domain[1];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
(<any>deepCopy).register({
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Shadowed name: 'source' Open
create: function (source) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var deepCopyAlgorithm = new DeepCopyAlgorithm();
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var [niceLow, niceTop] = d3TimeScale().domain([low, top]).nice(niceIntervalFn).domain();
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var hashGen = 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
var source = defaultObjs[index],
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var totalItems = xTotal(paramsList);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'memoize' Open
const memoize = <any>function (key) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var key in config) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var i = 0; i < source.length; i++) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var koeffTop = (deltaTop >= limit) ? -deltaTop : 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
for (... in ...) statements must be filtered with an if statement Open
for (var key in config) {
this[key] = config[key];
}
- Read upRead up
- Exclude checks
Rule: forin
Requires a for ... in
statement to be filtered with an if
statement.
Rationale
for (let key in someObject) {
if (someObject.hasOwnProperty(key)) {
// code here
}
}
Prevents accidental iteration over properties inherited from an object's prototype.
See MDN's for...in
documentation for more information about for...in
loops.
Also consider using a Map
or Set
if you're storing collections of objects.
Using Object
s can cause occasional edge case bugs, such as if a key is named "hasOwnProperty".
Config
Not configurable.
Examples
"forin": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
const memoize = <any>function (key) {
const cache = memoize.cache;
const address = String(hasher ? hasher.apply(this, arguments) : key);
if (!cache.hasOwnProperty(address)) {
cache[address] = func.apply(this, arguments);
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Shadowed name: 'source' Open
cacheResult: function (source, result) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var extent = [low, top];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var i = -1;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var unify = (v) => isDate(v) ? v.getTime() : v;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var hasher = func || ((x) => String(x));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
populate: function (deepCopyAlgorithm, source, result) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var k = t[0];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'deepCopy' Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'source' Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var i = 0; i < deepCopiers.length; i++) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var m = 10;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var chartSpec = chartInstanceRef.getSpec();
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var xTotal = (keys: string[]) => {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var len = array.length;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
(<any>deepCopy).deepCopiers = deepCopiers;
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Shadowed name: 'source' Open
canCopy: function (source) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'source' Open
deepCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var rootRef = funcTransformRules(fnSelectorPredicates(srcObject), srcObject);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var i = 0; i < length; i++) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var span = extent[1] - extent[0];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var step = Math.pow(10, Math.floor(Math.log(span / m) / Math.LN10));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var correction = [
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var d3TimeScale = (utc ? d3.scaleUtc : d3.scaleTime);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var r = btoa(encodeURIComponent(str)).replace(/=/g, '_');
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
(<any>deepCopy).register({
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Shadowed name: 'escape' Open
text.replace(matcher, function (match, escape, interpolate, evaluate, offset) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var xPart = ((keys: string[], k: string) => (xHash(data, keys)[k]));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var segment = ((max - min) / (parts - 1));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var i = 0; i < len; ++i) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'result' Open
return props.reduce((result, prop) => {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'source' Open
function deepCopy(source, maxDepth?) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'source' Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'source' Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'template' Open
var template: any = function (data) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'map' Open
].reduce((map, tag) => (map[tag] = true, map), {} as {[tag: string]: boolean});
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var [low, top] = (d3.extent(domain) as [Date, Date]);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var niceScale = d3TimeScale().domain([low, top]).nice(niceIntervalFn);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var hashMap: {[key: string]: string} = {};
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var deepCopiers = [];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var thisPass = this;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var result = deepCopier.create(source);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var ticks = niceScale.ticks();
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var last = ticks.length - 1;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var dataPrevRef = null;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var xHash = memoize(
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var level2Guide = chartSpec.unit.units[0].guide || {};
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var isApplicable = true;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'match' Open
source += text.slice(index, offset).replace(escaper, match => '\\' + escapes[match]);
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var min = domain[0];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
applyDeepCopier: function (deepCopier, source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Shadowed name: 'clone' Open
function clone(target) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var deepClone = (function () {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var chunks = parts >= 2 ?
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var testColorCode = ((x) => (/^(#|rgb\(|rgba\()/.test(x)));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var deltaTop = extent[1] - top;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var allowedOverflow = 100;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var countOfTicksInTheFacet = xPart(paramsList, key);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Type assertion using the '<>' syntax is forbidden. Use the 'as' syntax instead. Open
(<any>deepCopy).DeepCopier = DeepCopier;
- Read upRead up
- Exclude checks
Rule: no-angle-bracket-type-assertion
Requires the use of as Type
for type assertions instead of <Type>
.
Rationale
Both formats of type assertions have the same effect, but only as
type assertions
work in .tsx
files. This rule ensures that you have a consistent type assertion style
across your codebase.
Notes
- TypeScript Only
- Has Fix
Config
Not configurable.
Examples
"no-angle-bracket-type-assertion": true
For more information see this page.
Shadowed name: 'source' Open
this.recursiveDeepCopy = function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Array type using 'Array<t>' is forbidden. Use 'T[]' instead.</t> Open
export function flatten<T>(array: Array<T | T[]>): T[];
- Read upRead up
- Exclude checks
Rule: array-type
Requires using either 'T[]' or 'Array<t>' for arrays.</t>
Notes
- TypeScript Only
- Has Fix
Config
One of the following arguments must be provided:
-
"array"
enforces use ofT[]
for all types T. -
"generic"
enforces use ofArray<T>
for all types T. -
"array-simple"
enforces use ofT[]
ifT
is a simple type (primitive or type reference).
Examples
"array-type": true,array
"array-type": true,generic
"array-type": true,array-simple
Schema
{
"type": "string",
"enum": [
"array",
"generic",
"array-simple"
]
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var low = parseFloat(Math.min(...domain).toFixed(15));
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var limit = (step / 2);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var oneDay = 24 * 60 * 60 * 1000;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
canCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var arr = xHash(data, keys);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Shadowed name: 'source' Open
var source = '__p+=\'';
- Read upRead up
- Exclude checks
Rule: no-shadowed-variable
Disallows shadowing variable declarations.
Rationale
When a variable in a local scope and a variable in the containing scope have the same name, shadowing occurs. Shadowing makes it impossible to access the variable in the containing scope and obscures to what value an identifier actually refers. Compare the following snippets:
const a = 'no shadow';
function print() {
console.log(a);
}
print(); // logs 'no shadow'.
const a = 'no shadow';
function print() {
const a = 'shadow'; // TSLint will complain here.
console.log(a);
}
print(); // logs 'shadow'.
ESLint has an equivalent rule. For more background information, refer to this MDN closure doc.
Config
You can optionally pass an object to disable checking for certain kinds of declarations.
Possible keys are "class"
, "enum"
, "function"
, "import"
, "interface"
, "namespace"
, "typeAlias"
and "typeParameter"
. You can also pass "underscore
" to ignore variable names that begin with _
.
Just set the value to false
for the check you want to disable.
All checks default to true
, i.e. are enabled by default.
Note that you cannot disable variables and parameters.
The option "temporalDeadZone"
defaults to true
which shows errors when shadowing block scoped declarations in their
temporal dead zone. When set to false
parameters, classes, enums and variables declared
with let
or const
are not considered shadowed if the shadowing occurs within their
temporal dead zone.
The following example shows how the "temporalDeadZone"
option changes the linting result:
function fn(value) {
if (value) {
const tmp = value; // no error on this line if "temporalDeadZone" is false
return tmp;
}
let tmp = undefined;
if (!value) {
const tmp = value; // this line always contains an error
return tmp;
}
}
Examples
"no-shadowed-variable": true
"no-shadowed-variable": true,[object Object]
Schema
{
"type": "object",
"properties": {
"class": {
"type": "boolean"
},
"enum": {
"type": "boolean"
},
"function": {
"type": "boolean"
},
"import": {
"type": "boolean"
},
"interface": {
"type": "boolean"
},
"namespace": {
"type": "boolean"
},
"typeAlias": {
"type": "boolean"
},
"typeParameter": {
"type": "boolean"
},
"temporalDeadZone": {
"type": "boolean"
},
"underscore": {
"type": "boolean"
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var result = [];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var copiedObjects = this.copiedObjects;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var deltaLow = low - extent[0];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var data = chartSpec.sources['/'].data;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var allowedOverflow = 20;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var direction = angle === -90 ? -1 : 1;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var childrenArgIndex = 2;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Expected method shorthand in object literal ('{getCachedResult() {...}}'). Open
getCachedResult: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Identifier 'thisPass' is never reassigned; use 'const' instead of 'var'. Open
var thisPass = this;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'koeffLow' is never reassigned; use 'const' instead of 'var'. Open
var koeffLow = (deltaLow >= limit) ? -deltaLow : 0;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'chartSpec' is never reassigned; use 'const' instead of 'var'. Open
var chartSpec = chartInstanceRef.getSpec();
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'level2Guide' is never reassigned; use 'const' instead of 'var'. Open
var level2Guide = chartSpec.unit.units[0].guide || {};
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'countOfTicksInTheFacet' is never reassigned; use 'const' instead of 'var'. Open
var countOfTicksInTheFacet = xPart(paramsList, key);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'argument' is never reassigned; use 'const' instead of 'var'. Open
var argument = settings.variable || 'obj';
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function range(start: number, end?: number) {
if (arguments.length === 1) {
end = start;
start = 0;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function defaults<T, K, V, Q, R>(obj: T, obj1?: K): T & K;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function defaults<T, K, V, Q, R>(obj: T, obj1?: K, obj2?: V): T & K & V;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function defaults<T, K, V, Q, R>(obj: T, obj1?: K, obj2?: V, obj3?: Q): T & K & V & Q;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function memoize<A, B, R>(func: (a: A, b: B) => R, hasher?: (a: A, b: B) => string): (a: A, b: B) => R;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var index = 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var source = '__p+=\'';
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var argument = settings.variable || 'obj';
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
non-arrow functions are forbidden Open
create: function (source) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'deltaLow' is never reassigned; use 'const' instead of 'var'. Open
var deltaLow = low - extent[0];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'd3TimeScale' is never reassigned; use 'const' instead of 'var'. Open
var d3TimeScale = (utc ? d3.scaleUtc : d3.scaleTime);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'niceLow' is never reassigned; use 'const' instead of 'var'. Open
var [niceLow, niceTop] = d3TimeScale().domain([low, top]).nice(niceIntervalFn).domain();
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'unify' is never reassigned; use 'const' instead of 'var'. Open
var unify = (v) => isDate(v) ? v.getTime() : v;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'length' is never reassigned; use 'const' instead of 'var'. Open
var length = defaultObjs.length;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'newObj' is never reassigned; use 'const' instead of 'let'. Open
let newObj = Object.assign({}, obj);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'value' is never reassigned; use 'const' instead of 'let'. Open
let value = object[prop];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'testRegexp' is never reassigned; use 'const' instead of 'let'. Open
let testRegexp = RegExp(source);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Expected a 'for-of' loop instead of a 'for' loop with this simple iteration Open
for (var i = 0; i < source.length; i++) {
- Read upRead up
- Exclude checks
Rule: prefer-for-of
Recommends a 'for-of' loop over a standard 'for' loop if the index is only used to access the array being iterated.
Rationale
A for(... of ...) loop is easier to implement and read when the index is not needed.
Config
Not configurable.
Examples
"prefer-for-of": true
For more information see this page.
statements are not aligned Open
export function defaults<T, K, V, Q, R>(obj: T, obj1?: K, obj2?: V, obj3?: Q, obj4?: R): T & K & V & Q & R;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var template: any = function (data) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var attrsString = Object.keys(attrs).map(function (key) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Expected method shorthand in object literal ('{deepCopy() {...}}'). Open
deepCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Expected method shorthand in object literal ('{populate() {...}}'). Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Identifier 'deepCopyAlgorithm' is never reassigned; use 'const' instead of 'var'. Open
var deepCopyAlgorithm = new DeepCopyAlgorithm();
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'xPart' is never reassigned; use 'const' instead of 'var'. Open
var xPart = ((keys: string[], k: string) => (xHash(data, keys)[k]));
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'escapes' is never reassigned; use 'const' instead of 'let'. Open
let escapes = {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function throttleLastEvent(
last: {e?: string, ts?: number},
eventType: string,
handler: (...args) => void,
limitFromPrev: 'requestAnimationFrame' | number = 0
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function toRadian(degree: number) {
return (degree / 180) * Math.PI;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function memoize<R>(
func: (...args: any[]) => R,
hasher?: (...args: any[]) => string
): (...args: any[]) => R;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var source = defaultObjs[index],
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var result = {};
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Identifier 'err' is never reassigned; use 'const' instead of 'var'. Open
var err = m / span * step;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'correction' is never reassigned; use 'const' instead of 'var'. Open
var correction = [
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var key = hasher(item);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Identifier 'niceTop' is never reassigned; use 'const' instead of 'var'. Open
var [niceLow, niceTop] = d3TimeScale().domain([low, top]).nice(niceIntervalFn).domain();
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'r' is never reassigned; use 'const' instead of 'var'. Open
var r = btoa(encodeURIComponent(str)).replace(/=/g, '_');
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'matcher' is never reassigned; use 'const' instead of 'var'. Open
var matcher = RegExp([
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Expected a 'for-of' loop instead of a 'for' loop with this simple iteration Open
for (var i = 0; i < deepCopiers.length; i++) {
- Read upRead up
- Exclude checks
Rule: prefer-for-of
Recommends a 'for-of' loop over a standard 'for' loop if the index is only used to access the array being iterated.
Rationale
A for(... of ...) loop is easier to implement and read when the index is not needed.
Config
Not configurable.
Examples
"prefer-for-of": true
For more information see this page.
Identifier 'curr' is never reassigned; use 'const' instead of 'var'. Open
var curr = {e: eventType, ts: Date.now()};
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function unique<T>(array: T[], func?: (T) => string): T[] {
var hash = {};
var result = [];
var len = array.length;
var hasher = func || ((x) => String(x));
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function niceZeroBased(domain: number[]) {
var m = 10;
var low = parseFloat(Math.min(...domain).toFixed(15));
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function createMultiSorter<T>(...sorters: ((a: T, b: T) => number)[]) {
return (a, b) => {
var result = 0;
sorters.every((s) => {
result = s(a, b);
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
non-arrow functions are forbidden Open
var deepClone = (function () {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
canCopy: function () {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'deepCopiers' is never reassigned; use 'const' instead of 'var'. Open
var deepCopiers = [];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'span' is never reassigned; use 'const' instead of 'var'. Open
var span = extent[1] - extent[0];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'xTotal' is never reassigned; use 'const' instead of 'var'. Open
var xTotal = (keys: string[]) => {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'source' is never reassigned; use 'const' instead of 'var'. Open
var source = defaultObjs[index],
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'render' is never reassigned; use 'const' instead of 'var'. Open
var render = new Function(settings.variable || 'obj', source);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'hashMap' is never reassigned; use 'const' instead of 'var'. Open
var hashMap: {[key: string]: string} = {};
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function splitEvenly(domain: [number, number], parts: number): number[] {
var min = domain[0];
var max = domain[1];
var segment = ((max - min) / (parts - 1));
var chunks = parts >= 2 ?
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function flatten<T>(array: Array<T | T[]>): T[];
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var result = 0;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
non-arrow functions are forbidden Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
var attrsString = Object.keys(attrs).map(function (key) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'key' is never reassigned; use 'const' instead of 'var'. Open
for (var key in config) {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'd' is never reassigned; use 'const' instead of 'let'. Open
let d = (top || 1);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'data' is never reassigned; use 'const' instead of 'var'. Open
var data = chartSpec.sources['/'].data;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'deepClone' is never reassigned; use 'const' instead of 'var'. Open
var deepClone = (function () {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function extRGBColor(x: string) {
return (testColorCode(x) ? x : '');
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function escape(string: string) {
string = string == null ? '' : String(string);
return testRegexp.test(string) ? string.replace(replaceRegexp, match => map[match]) : string;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var matcher = RegExp([
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Expected method shorthand in object literal ('{cacheResult() {...}}'). Open
cacheResult: function (source, result) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Expected method shorthand in object literal ('{create() {...}}'). Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
non-arrow functions are forbidden Open
canCopy: function (source) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'shouldContinue' is never reassigned; use 'const' instead of 'var'. Open
var shouldContinue = enterFn(root, level);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'k' is never reassigned; use 'const' instead of 'let'. Open
let k = (top >= 0) ? -1 : 1;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'deltaTop' is never reassigned; use 'const' instead of 'var'. Open
var deltaTop = extent[1] - top;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'span' is never reassigned; use 'const' instead of 'var'. Open
var span = (+top - +low);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'last' is never reassigned; use 'const' instead of 'var'. Open
var last = ticks.length - 1;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'tickPxSize' is never reassigned; use 'const' instead of 'var'. Open
var tickPxSize = (size - (facetSize * pad)) / totalItems;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'chunks' is never reassigned; use 'const' instead of 'var'. Open
var chunks = parts >= 2 ?
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'allowedOverflow' is never reassigned; use 'const' instead of 'var'. Open
var allowedOverflow = 100;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'escaper' is never reassigned; use 'const' instead of 'let'. Open
let escaper = /\\|'|\r|\n|\u2028|\u2029/g;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'source' is never reassigned; use 'const' instead of 'let'. Open
let source = '(?:' + Object.keys(map).join('|') + ')';
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function memoize<A, B, C, R>(
func: (a: A, b: B, c: C) => R,
hasher?: (a: A, b: B, c: C) => string
): (a: A, b: B, c: C) => R;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var attrs = arguments[1];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Identifier 'deepCopier' is never reassigned; use 'const' instead of 'var'. Open
var deepCopier = deepCopiers[i];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'result' is never reassigned; use 'const' instead of 'var'. Open
var result = deepCopier.create(source);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'ticks' is never reassigned; use 'const' instead of 'var'. Open
var ticks = niceScale.ticks();
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'xHash' is never reassigned; use 'const' instead of 'var'. Open
var xHash = memoize(
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'group' is never reassigned; use 'const' instead of 'var'. Open
var group = func(v);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'noMatch' is never reassigned; use 'const' instead of 'var'. Open
var noMatch = /(.)^/;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'templateSettings' is never reassigned; use 'const' instead of 'let'. Open
let templateSettings = {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function generateRatioFunction(dimPropName: string, paramsList: string[], chartInstanceRef: Plot) {
var unify = (v) => isDate(v) ? v.getTime() : v;
var dataNewSnap = 0;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function extCSSClass(x: string) {
return (testColorCode(x) ? '' : x);
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Expected method shorthand in object literal ('{populate() {...}}'). Open
populate: function (deepCopyAlgorithm, source, result) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Expected method shorthand in object literal ('{applyDeepCopier() {...}}'). Open
applyDeepCopier: function (deepCopier, source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Expected method shorthand in object literal ('{canCopy() {...}}'). Open
canCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
non-arrow functions are forbidden Open
this.recursiveDeepCopy = function (source) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
canCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
attrsString = Object.keys(attrs).map(function (key) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'length' is never reassigned; use 'const' instead of 'var'. Open
var length = copiedObjects.length;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'hash' is never reassigned; use 'const' instead of 'var'. Open
var hash = {};
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'key' is never reassigned; use 'const' instead of 'var'. Open
var key = hasher(item);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var item = array[i];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Identifier 'l' is never reassigned; use 'const' instead of 'var'. Open
l = keys.length;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'result' is never reassigned; use 'const' instead of 'var'. Open
var result = {};
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var index = 0; index < length; index++) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
statements are not aligned Open
export function generateHash(str: string) {
var r = btoa(encodeURIComponent(str)).replace(/=/g, '_');
if (!hashMap.hasOwnProperty(r)) {
hashMap[r] = (`H${++hashGen}`);
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var render = new Function(settings.variable || 'obj', source);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
statements are not aligned Open
export function hasXOverflow(x: number, size: number, angle: number, maxX: number) {
var allowedOverflow = 100;
var direction = angle === 90 ? -1 : 1;
return (x + size * direction) - maxX > allowedOverflow;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var result: any = src;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
statements are not aligned Open
export function hasYOverflow(y: number, size: number, angle: number, maxY: number) {
var allowedOverflow = 20;
var direction = angle === -90 ? -1 : 1;
return (y + size * direction) - maxY > allowedOverflow;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Expected method shorthand in object literal ('{create() {...}}'). Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
statements are not aligned Open
export function flatten(array: any): any[] {
if (!Array.isArray(array)) {
return array;
}
return [].concat(...array.map(x => flatten(x)));
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Expected method shorthand in object literal ('{create() {...}}'). Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
statements are not aligned Open
export function intersection<T>(arr1: T[], arr2: T[]) {
return arr1.filter(x => arr2.indexOf(x) !== -1);
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function defaults<T>(obj: T, ...defaultObjs: T[]): T {
var length = defaultObjs.length;
if (length === 0 || !obj) {
return obj;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Identifier 'rootRef' is never reassigned; use 'const' instead of 'var'. Open
var rootRef = funcTransformRules(fnSelectorPredicates(srcObject), srcObject);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function template(text: string, settings?, oldSettings?): (data?) => string {
if (!settings && oldSettings) {
settings = oldSettings;
}
settings = defaults({}, settings, templateSettings);
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Assigning this
reference to local variable not allowed: thisPass. Open
var thisPass = this;
- Read upRead up
- Exclude checks
Rule: no-this-assignment
Disallows unnecessary references to this
.
Rationale
Assigning a variable to this
instead of properly using arrow lambdas may be a symptom of pre-ES6 practices
or not managing scope well.
Instead of storing a reference to this
and using it inside a function () {
:
const self = this;
setTimeout(function () {
self.doWork();
});
Use () =>
arrow lambdas, as they preserve this
scope for you:
setTimeout(() => {
this.doWork();
});
Config
Two options may be provided on an object:
-
allow-destructuring
allows using destructuring to access members ofthis
(e.g.{ foo, bar } = this;
). -
allowed-names
may be specified as a list of regular expressions to match allowed variable names.
Examples
"no-this-assignment": true
"no-this-assignment": true,[object Object]
Schema
{
"additionalProperties": false,
"properties": {
"allow-destructuring": {
"type": "boolean"
},
"allowed-names": {
"listType": "string",
"type": "list"
}
},
"type": "object"
}
For more information see this page.
Identifier 'limit' is never reassigned; use 'const' instead of 'var'. Open
var limit = (step / 2);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Do not use the Function constructor to create functions. Open
var render = new Function(settings.variable || 'obj', source);
- Read upRead up
- Exclude checks
Rule: function-constructor
Prevents using the built-in Function constructor.
Rationale
Calling the constructor directly is similar to eval
, which is a symptom of design issues.
String inputs don't receive type checking and can cause performance issues, particularly when dynamically created.
If you need to dynamically create functions, use "factory" functions that themselves return functions.
Config
Not configurable.
Examples
"function-constructor": true
For more information see this page.
Identifier 'seed' is never reassigned; use 'const' instead of 'let'. Open
let seed = (dataPrevRef === data) ? dataNewSnap : (++dataNewSnap);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'diff' is never reassigned; use 'const' instead of 'var'. Open
var diff = ((last.e && (last.e === curr.e)) ? (curr.ts - last.ts) : (limitFromPrev));
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'min' is never reassigned; use 'const' instead of 'var'. Open
var min = domain[0];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'direction' is never reassigned; use 'const' instead of 'var'. Open
var direction = angle === -90 ? -1 : 1;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'hasher' is never reassigned; use 'const' instead of 'var'. Open
var hasher = func || ((x) => String(x));
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'map' is never reassigned; use 'const' instead of 'let'. Open
let map = {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function memoize(func, hasher) {
const memoize = <any>function (key) {
const cache = memoize.cache;
const address = String(hasher ? hasher.apply(this, arguments) : key);
if (!cache.hasOwnProperty(address)) {
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function pick(object: Object, ...props: string[]): Object {
var result = {};
if (object == null) {
return result;
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Expected method shorthand in object literal ('{canCopy() {...}}'). Open
canCopy: function () {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Expected method shorthand in object literal ('{populate() {...}}'). Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
non-arrow functions are forbidden Open
populate: function (deepCopy, source, result) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'copiedObjects' is never reassigned; use 'const' instead of 'var'. Open
var copiedObjects = this.copiedObjects;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'koeffTop' is never reassigned; use 'const' instead of 'var'. Open
var koeffTop = (deltaTop >= limit) ? -deltaTop : 0;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'niceScale' is never reassigned; use 'const' instead of 'var'. Open
var niceScale = d3TimeScale().domain([low, top]).nice(niceIntervalFn);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'totalItems' is never reassigned; use 'const' instead of 'var'. Open
var totalItems = xTotal(paramsList);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'segment' is never reassigned; use 'const' instead of 'var'. Open
var segment = ((max - min) / (parts - 1));
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'result' is never reassigned; use 'const' instead of 'var'. Open
var result = [];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'len' is never reassigned; use 'const' instead of 'var'. Open
var len = array.length;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'keys' is never reassigned; use 'const' instead of 'var'. Open
keys = isObject(source) ? Object.keys(source) : [],
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'template' is never reassigned; use 'const' instead of 'var'. Open
var template: any = function (data) {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function normalizeAngle(angle: number) {
if (Math.abs(angle) >= 360) {
angle = (angle % 360);
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function omit<T>(obj: T, ...props: string[]): T {
let newObj = Object.assign({}, obj);
props.forEach((prop) => {
delete newObj[prop];
});
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function memoize<A, R>(func: (a: A) => R, hasher?: (a: A) => string): (a: A) => R;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var group = func(v);
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
non-arrow functions are forbidden Open
populate: function (deepCopyAlgorithm, source, result) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'extent' is never reassigned; use 'const' instead of 'var'. Open
var extent = [low, top];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'allowedOverflow' is never reassigned; use 'const' instead of 'var'. Open
var allowedOverflow = 20;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function niceTimeDomain(domain: Date[], niceIntervalFn: d3.CountableTimeInterval, {utc} = {utc: false}) {
var [low, top] = (d3.extent(domain) as [Date, Date]);
var span = (+top - +low);
var d3TimeScale = (utc ? d3.scaleUtc : d3.scaleTime);
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function union<T>(arr1: T[], arr2: T[]): T[] {
return unique(arr1.concat(arr2));
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Type assertion on object literals is forbidden, use a type annotation instead. Open
].reduce((map, tag) => (map[tag] = true, map), {} as {[tag: string]: boolean});
- Read upRead up
- Exclude checks
Rule: no-object-literal-type-assertion
Forbids an object literal to appear in a type assertion expression.
Casting to any
or to unknown
is still allowed.
Rationale
Always prefer const x: T = { ... };
to const x = { ... } as T;
.
The type assertion in the latter case is either unnecessary or hides an error.
The compiler will warn for excess properties with this syntax, but not missing required fields.
For example: const x: { foo: number } = {}
will fail to compile, but
const x = {} as { foo: number }
will succeed.
Additionally, the const assertion const x = { foo: 1 } as const
,
introduced in TypeScript 3.4, is considered beneficial and is ignored by this rule.
Notes
- TypeScript Only
Config
One option may be configured:
-
allow-arguments
allows type assertions to be used on object literals inside call expressions.
Examples
"no-object-literal-type-assertion": true
"no-object-literal-type-assertion": true,[object Object]
Schema
{
"type": "object",
"properties": {
"allow-arguments": {
"type": "boolean"
}
},
"additionalProperties": false
}
For more information see this page.
Do not use comma operator here because it can be easily misunderstood or lead to unintended bugs. Open
].reduce((map, tag) => (map[tag] = true, map), {} as {[tag: string]: boolean});
- Read upRead up
- Exclude checks
Rule: ban-comma-operator
Disallows the comma operator to be used.
Read more about the comma operator here.
Rationale
Using the comma operator can create a potential for many non-obvious bugs or lead to misunderstanding of code.
Examples
foo((bar, baz)); // evaluates to 'foo(baz)' because of the extra parens - confusing and not obvious
switch (foo) {
case 1, 2: // equals 'case 2' - probably intended 'case 1: case2:'
return true;
case 3:
return false;
}
let x = (y = 1, z = 2); // x is equal to 2 - this may not be immediately obvious.
Examples
"ban-comma-operator": true
For more information see this page.
Expected method shorthand in object literal ('{canCopy() {...}}'). Open
canCopy: function (source) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
non-arrow functions are forbidden Open
(<any>deepCopy).register = function (deepCopier) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
create: function (source) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'key' is never reassigned; use 'const' instead of 'var'. Open
for (var key in source) {
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'arr' is never reassigned; use 'const' instead of 'var'. Open
var arr = xHash(data, keys);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'testColorCode' is never reassigned; use 'const' instead of 'var'. Open
var testColorCode = ((x) => (/^(#|rgb\(|rgba\()/.test(x)));
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'replaceRegexp' is never reassigned; use 'const' instead of 'let'. Open
let replaceRegexp = RegExp(source, 'g');
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
== should be === Open
if (typeof target == 'object') {
- Read upRead up
- Exclude checks
Rule: triple-equals
Requires ===
and !==
in place of ==
and !=
.
Config
Two arguments may be optionally provided:
-
"allow-null-check"
allows==
and!=
when comparing tonull
. -
"allow-undefined-check"
allows==
and!=
when comparing toundefined
.
Examples
"triple-equals": true
"triple-equals": true,allow-null-check
"triple-equals": true,allow-undefined-check
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-null-check",
"allow-undefined-check"
]
},
"minLength": 0,
"maxLength": 2
}
For more information see this page.
statements are not aligned Open
export function clone<T>(obj: T): T {
return deepClone(obj);
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
var hashMap: {[key: string]: string} = {};
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function isSpecRectCoordsOnly(root: Unit) {
var isApplicable = true;
try {
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function groupBy<T>(array: T[], func?: (item: T) => string): {[key: string]: T[]} {
return array.reduce((obj, v) => {
var group = func(v);
obj[group] = obj[group] || [];
obj[group].push(v);
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var key = keys[i];
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Expected method shorthand in object literal ('{canCopy() {...}}'). Open
canCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
non-arrow functions are forbidden Open
text.replace(matcher, function (match, escape, interpolate, evaluate, offset) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'cachedResult' is never reassigned; use 'const' instead of 'var'. Open
var cachedResult = this.getCachedResult(source);
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'm' is never reassigned; use 'const' instead of 'var'. Open
var m = 10;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'k' is never reassigned; use 'const' instead of 'var'. Open
var k = t[0];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'facetSize' is never reassigned; use 'const' instead of 'var'. Open
var facetSize = varSet.length;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
statements are not aligned Open
export function isDate(obj) {
return obj instanceof Date && !isNaN(Number(obj));
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function isObject(obj) {
return obj != null && typeof obj === 'object';
}
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
var hashGen = 0;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
statements are not aligned Open
export function memoize<R>(func: () => R, hasher?: () => string): () => R;
- Read upRead up
- Exclude checks
Rule: align
Enforces vertical alignment.
Rationale
Helps maintain a readable, consistent style in your codebase.
Consistent alignment for code statements helps keep code readable and clear. Statements misaligned from the standard can be harder to read and understand.
Notes
- Has Fix
Config
Five arguments may be optionally provided:
-
"parameters"
checks alignment of function parameters. -
"arguments"
checks alignment of function call arguments. -
"statements"
checks alignment of statements. -
"members"
checks alignment of members of classes, interfaces, type literal, object literals and object destructuring. -
"elements"
checks alignment of elements of array literals, array destructuring and tuple types.
Examples
"align": true,parameters,statements
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"arguments",
"elements",
"members",
"parameters",
"statements"
]
},
"minLength": 1,
"maxLength": 5
}
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
var length = defaultObjs.length;
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Forbidden 'var' keyword, use 'let' or 'const' instead Open
for (var i = 0; i < l; i++) {
- Read upRead up
- Exclude checks
Rule: no-var-keyword
Disallows usage of the var
keyword.
Use let
or const
instead.
Rationale
Declaring variables using var
has several edge case behaviors that make var
unsuitable for modern code.
Variables declared by var
have their parent function block as their scope, ignoring other control flow statements.
var
s have declaration "hoisting" (similar to function
s) and can appear to be used before declaration.
Variables declared by const
and let
instead have as their scope the block in which they are defined,
and are not allowed to used before declaration or be re-declared with another const
or let
.
Notes
- Has Fix
Config
Not configurable.
Examples
"no-var-keyword": true
For more information see this page.
Expected method shorthand in object literal ('{create() {...}}'). Open
create: function (source) { // eslint-disable-line
- Read upRead up
- Exclude checks
Rule: object-literal-shorthand
Enforces/disallows use of ES6 object literal shorthand.
Notes
- Has Fix
Config
"always"
assumed to be default option, thus with no options provided
the rule enforces object literal methods and properties shorthands.
With "never"
option provided, any shorthand object literal syntax causes an error.
The rule can be configured in a more granular way.
With {"property": "never"}
provided (which is equivalent to {"property": "never", "method": "always"}
),
the rule only flags property shorthand assignments,
and respectively with {"method": "never"}
(equivalent to {"property": "always", "method": "never"}
),
the rule fails only on method shorthands.
Examples
"object-literal-shorthand": true
"object-literal-shorthand": true,never
"object-literal-shorthand": true,[object Object]
Schema
{
"oneOf": [
{
"type": "string",
"enum": [
"never"
]
},
{
"type": "object",
"properties": {
"property": {
"type": "string",
"enum": [
"never"
]
},
"method": {
"type": "string",
"enum": [
"never"
]
}
},
"minProperties": 1,
"maxProperties": 2
}
]
}
For more information see this page.
Multiple variable declarations in the same statement are forbidden Open
var source = defaultObjs[index],
keys = isObject(source) ? Object.keys(source) : [],
l = keys.length;
- Read upRead up
- Exclude checks
Rule: one-variable-per-declaration
Disallows multiple variable definitions in the same declaration statement.
Config
One argument may be optionally provided:
-
ignore-for-loop
allows multiple variable definitions in a for loop declaration.
Examples
"one-variable-per-declaration": true
"one-variable-per-declaration": true,ignore-for-loop
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"ignore-for-loop"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
non-arrow functions are forbidden Open
canCopy: function (source) {
- Read upRead up
- Exclude checks
Rule: only-arrow-functions
Disallows traditional (non-arrow) function expressions.
Note that non-arrow functions are allowed if 'this' appears somewhere in its body (as such functions cannot be converted to arrow functions).
Rationale
Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.
Config
Two arguments may be optionally provided:
-
"allow-declarations"
allows standalone function declarations. -
"allow-named-functions"
allows the expressionfunction foo() {}
but notfunction() {}
.
Examples
"only-arrow-functions": true
"only-arrow-functions": true,allow-declarations,allow-named-functions
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-declarations",
"allow-named-functions"
]
},
"minLength": 0,
"maxLength": 1
}
For more information see this page.
Identifier 'oneDay' is never reassigned; use 'const' instead of 'var'. Open
var oneDay = 24 * 60 * 60 * 1000;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'max' is never reassigned; use 'const' instead of 'var'. Open
var max = domain[1];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'direction' is never reassigned; use 'const' instead of 'var'. Open
var direction = angle === 90 ? -1 : 1;
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'item' is never reassigned; use 'const' instead of 'var'. Open
var item = array[i];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Identifier 'key' is never reassigned; use 'const' instead of 'var'. Open
var key = keys[i];
- Read upRead up
- Exclude checks
Rule: prefer-const
Requires that variable declarations use const
instead of let
and var
if possible.
If a variable is only assigned to once when it is declared, it should be declared using 'const'
Notes
- Has Fix
Config
An optional object containing the property "destructuring" with two possible values:
- "any" (default) - If any variable in destructuring can be const, this rule warns for those variables.
- "all" - Only warns if all variables in destructuring can be const.
Examples
"prefer-const": true
"prefer-const": true,[object Object]
Schema
{
"type": "object",
"properties": {
"destructuring": {
"type": "string",
"enum": [
"all",
"any"
]
}
}
}
For more information see this page.
Use the object spread operator instead. Open
let newObj = Object.assign({}, obj);
- Read upRead up
- Exclude checks
Rule: prefer-object-spread
Enforces the use of the ES2018 object spread operator over Object.assign()
where appropriate.
Rationale
Object spread allows for better type checking and inference.
Notes
- Has Fix
Config
Not configurable.
Examples
"prefer-object-spread": true
For more information see this page.