Showing 24 of 24 total issues
Function detectBrowserVersion
has a Cognitive Complexity of 13 (exceeds 5 allowed). Consider refactoring. Open
export function detectBrowserVersion(
nav: {
userAgent: string;
appName?: string;
appVersion?: string;
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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 detectBrowserName
has 31 lines of code (exceeds 25 allowed). Consider refactoring. Open
function detectBrowserName(userAgent: string): BrowserName | undefined {
if (isChrome(userAgent)) {
return 'Chrome';
}
Function detectBrowserName
has a Cognitive Complexity of 10 (exceeds 5 allowed). Consider refactoring. Open
function detectBrowserName(userAgent: string): BrowserName | undefined {
if (isChrome(userAgent)) {
return 'Chrome';
}
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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 detectBrowserVersion
has 27 lines of code (exceeds 25 allowed). Consider refactoring. Open
export function detectBrowserVersion(
nav: {
userAgent: string;
appName?: string;
appVersion?: string;
Similar blocks of code found in 2 locations. Consider refactoring. Open
userAgent.includes('Chrome') &&
!userAgent.includes('Chromium') &&
!userAgent.includes('SamsungBrowser') &&
!userAgent.includes('OPR') &&
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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 51.
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
userAgent.includes('Safari') &&
!userAgent.includes('Chrome') &&
!userAgent.includes('Chromium') &&
!userAgent.includes('Android')
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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 51.
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
Avoid too many return
statements within this function. Open
return 'Firefox';
Avoid too many return
statements within this function. Open
return 'UC Browser';
Avoid too many return
statements within this function. Open
return 'Edge';
Avoid too many return
statements within this function. Open
return 'Android Browser';
Avoid too many return
statements within this function. Open
return 'QQ Browser';
Avoid too many return
statements within this function. Open
return 'IE';
Avoid too many return
statements within this function. Open
return undefined;
unused expression, expected an assignment or function call Open
import type { BrowserName } from './browser-detection';
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- Exclude checks
Rule: no-unused-expression
Disallows unused expression statements.
Unused expressions are expression statements which are not assignments or function calls (and thus usually no-ops).
Rationale
Detects potential errors where an assignment or function call was intended.
Config
Three arguments may be optionally provided:
-
allow-fast-null-checks
allows to use logical operators to perform fast null checks and perform method or function calls for side effects (e.g.e && e.preventDefault()
). -
allow-new
allows 'new' expressions for side effects (e.g.new ModifyGlobalState();
. -
allow-tagged-template
allows tagged templates for side effects (e.g.this.add\
foo`;`.
Examples
"no-unused-expression": true
"no-unused-expression": true,allow-fast-null-checks
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-fast-null-checks",
"allow-new",
"allow-tagged-template"
]
},
"minLength": 0,
"maxLength": 3
}
For more information see this page.
unused expression, expected an assignment or function call Open
import type { BrowserName } from './browser-detection';
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- Exclude checks
Rule: no-unused-expression
Disallows unused expression statements.
Unused expressions are expression statements which are not assignments or function calls (and thus usually no-ops).
Rationale
Detects potential errors where an assignment or function call was intended.
Config
Three arguments may be optionally provided:
-
allow-fast-null-checks
allows to use logical operators to perform fast null checks and perform method or function calls for side effects (e.g.e && e.preventDefault()
). -
allow-new
allows 'new' expressions for side effects (e.g.new ModifyGlobalState();
. -
allow-tagged-template
allows tagged templates for side effects (e.g.this.add\
foo`;`.
Examples
"no-unused-expression": true
"no-unused-expression": true,allow-fast-null-checks
Schema
{
"type": "array",
"items": {
"type": "string",
"enum": [
"allow-fast-null-checks",
"allow-new",
"allow-tagged-template"
]
},
"minLength": 0,
"maxLength": 3
}
For more information see this page.
Use a conditional expression instead of assigning to 'end' in multiple places. Open
if (preNum.indexOf('.', 2) > 0) {
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- Exclude checks
Rule: prefer-conditional-expression
Recommends to use a conditional expression instead of assigning to the same thing in each branch of an if statement.
Rationale
This reduces duplication and can eliminate an unnecessary variable declaration.
Config
If check-else-if
is specified, the rule also checks nested if-else-if statements.
Examples
"prefer-conditional-expression": true
"prefer-conditional-expression": true,check-else-if
Schema
{
"type": "string",
"enum": [
"check-else-if"
]
}
For more information see this page.
Missing semicolon Open
import type { BrowserName } from './browser-detection';
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- Exclude checks
Rule: semicolon
Enforces consistent semicolon usage at the end of every statement.
Notes
- Has Fix
Config
One of the following arguments must be provided:
-
"always"
enforces semicolons at the end of every statement. -
"never"
disallows semicolons at the end of every statement except for when they are necessary.
The following arguments may be optionally provided:
-
"ignore-interfaces"
skips checking semicolons at the end of interface members. -
"ignore-bound-class-methods"
skips checking semicolons at the end of bound class methods. -
"strict-bound-class-methods"
disables any special handling of bound class methods and treats them as any other assignment. This option overrides"ignore-bound-class-methods"
.
Examples
"semicolon": true,always
"semicolon": true,never
"semicolon": true,always,ignore-interfaces
"semicolon": true,always,ignore-bound-class-methods
Schema
{
"type": "array",
"items": [
{
"type": "string",
"enum": [
"always",
"never"
]
},
{
"type": "string",
"enum": [
"ignore-interfaces"
]
}
],
"additionalItems": false
}
For more information see this page.
Missing semicolon Open
})
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- Exclude checks
Rule: semicolon
Enforces consistent semicolon usage at the end of every statement.
Notes
- Has Fix
Config
One of the following arguments must be provided:
-
"always"
enforces semicolons at the end of every statement. -
"never"
disallows semicolons at the end of every statement except for when they are necessary.
The following arguments may be optionally provided:
-
"ignore-interfaces"
skips checking semicolons at the end of interface members. -
"ignore-bound-class-methods"
skips checking semicolons at the end of bound class methods. -
"strict-bound-class-methods"
disables any special handling of bound class methods and treats them as any other assignment. This option overrides"ignore-bound-class-methods"
.
Examples
"semicolon": true,always
"semicolon": true,never
"semicolon": true,always,ignore-interfaces
"semicolon": true,always,ignore-bound-class-methods
Schema
{
"type": "array",
"items": [
{
"type": "string",
"enum": [
"always",
"never"
]
},
{
"type": "string",
"enum": [
"ignore-interfaces"
]
}
],
"additionalItems": false
}
For more information see this page.
Assignments in conditional expressions are forbidden Open
if ((temp = /version\/(\d+)/i.exec(userAgent)) !== null) {
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- Exclude checks
Rule: no-conditional-assignment
Disallows any type of assignment in conditionals.
This applies to do-while
, for
, if
, and while
statements and conditional (ternary) expressions.
Rationale
Assignments in conditionals are often typos:
for example if (var1 = var2)
instead of if (var1 == var2)
.
They also can be an indicator of overly clever code which decreases maintainability.
Config
Not configurable.
Examples
"no-conditional-assignment": true
For more information see this page.
Shadowed name: 'temp' Open
const temp = /\b(Edge)\/(\d+)/.exec(userAgent);
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- 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.