Function init
has a Cognitive Complexity of 21 (exceeds 5 allowed). Consider refactoring. Open
export const init: ModuleFn = ({ store, provider, singleStory }, { runCheck = true } = {}) => {
const api: SubAPI = {
findRef: (source) => {
const refs = api.getRefs();
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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 checkRef
has 44 lines of code (exceeds 25 allowed). Consider refactoring. Open
checkRef: async (ref) => {
const { id, url, version, type } = ref;
const isPublic = type === 'server-checked';
// ref's type starts as either 'unknown' or 'server-checked'
Type assertion on object literals is forbidden, use a type annotation instead. Open
const ref = { id, url, versions, title, stories: {} } as SetRefData;
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- 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.
Shadowed name: 'refs' Open
const refs = api.getRefs();
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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.
Type assertion on object literals is forbidden, use a type annotation instead. Open
}, {} as StoriesRaw);
- 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.
Type assertion on object literals is forbidden, use a type annotation instead. Open
loadedData.error = {
message: dedent`
Error: Loading of ref failed
at fetch (lib/api/src/modules/refs.ts)
- 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.
Type assertion on object literals is forbidden, use a type annotation instead. Open
}, {} as StoriesHash);
- 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.
Shadowed name: 'refs' Open
const { refs = {} } = store.getState();
- 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.