Function collapseAllStories
has 49 lines of code (exceeds 25 allowed). Consider refactoring. Open
export const collapseAllStories = (stories: StoriesHash) => {
// keep track of component IDs that have been rewritten to the ID of their first leaf child
const componentIdToLeafId: Record<string, string> = {};
// 1) remove all leaves
Function collapseDocsOnlyStories
has 34 lines of code (exceeds 25 allowed). Consider refactoring. Open
export const collapseDocsOnlyStories = (storiesHash: StoriesHash) => {
// keep track of component IDs that have been rewritten to the ID of their first leaf child
const componentIdToLeafId: Record<string, string> = {};
const docsOnlyStoriesRemoved = Object.values(storiesHash).filter((item) => {
if (item.isLeaf && item.parameters && item.parameters.docsOnly) {
Function collapseDocsOnlyStories
has a Cognitive Complexity of 11 (exceeds 5 allowed). Consider refactoring. Open
export const collapseDocsOnlyStories = (storiesHash: StoriesHash) => {
// keep track of component IDs that have been rewritten to the ID of their first leaf child
const componentIdToLeafId: Record<string, string> = {};
const docsOnlyStoriesRemoved = Object.values(storiesHash).filter((item) => {
if (item.isLeaf && item.parameters && item.parameters.docsOnly) {
- 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 componentsFlattened
has 30 lines of code (exceeds 25 allowed). Consider refactoring. Open
const componentsFlattened = leavesRemoved.map((item) => {
const { id, isComponent, children, ...rest } = item;
// this is a folder, so just leave it alone
if (!isComponent) {
Function collapseAllStories
has a Cognitive Complexity of 10 (exceeds 5 allowed). Consider refactoring. Open
export const collapseAllStories = (stories: StoriesHash) => {
// keep track of component IDs that have been rewritten to the ID of their first leaf child
const componentIdToLeafId: Record<string, string> = {};
// 1) remove all leaves
- 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
unused expression, expected an assignment or function call Open
import type { Story, StoriesHash } from '@storybook/api';
- Read upRead up
- 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.
Do not use comma operator here because it can be easily misunderstood or lead to unintended bugs. Open
import type { Story, StoriesHash } from '@storybook/api';
- 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.
Missing semicolon Open
import type { Story, StoriesHash } from '@storybook/api';
- Read upRead up
- 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
import type { Story, StoriesHash } from '@storybook/api';
- Read upRead up
- 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.
Type assertion on object literals is forbidden, use a type annotation instead. Open
const result = {} 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.
Missing semicolon Open
import type { Story, StoriesHash } from '@storybook/api';
- Read upRead up
- 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.
unused expression, expected an assignment or function call Open
import type { Story, StoriesHash } from '@storybook/api';
- Read upRead up
- 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 { Story, StoriesHash } from '@storybook/api';
- Read upRead up
- 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.
Type assertion on object literals is forbidden, use a type annotation instead. Open
const result = {} 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.