Configuration

The configuration that is contained inside the file biome.json

`$schema`

A field for the JSON schema specification

`css`

Specific configuration for the Css language

Options applied to CSS files

`css.formatter`

CSS formatter options

Options that changes how the CSS formatter behaves

`css.formatter.enabled`

Control the formatter for CSS (and its super languages) files.

`css.formatter.indentStyle`

The indent style applied to CSS (and its super languages) files.

`css.formatter.indentWidth`

The size of the indentation applied to CSS (and its super languages) files. Default to 2.

`css.formatter.lineEnding`

The type of line ending applied to CSS (and its super languages) files.

`css.formatter.lineWidth`

What’s the max width of a line applied to CSS (and its super languages) files. Defaults to 80.

Validated value for the line_width formatter options

The allowed range of values is 1..=320

`css.formatter.quoteStyle`

The type of quotes used in CSS code. Defaults to double.

`css.linter`

CSS linter options

Options that changes how the CSS linter behaves

`css.linter.enabled`

Control the linter for CSS (and its super languages) files.

`css.parser`

CSS parsing options

Options that changes how the CSS parser behaves

`css.parser.allowWrongLineComments`

Allow comments to appear on incorrect lines in .css files

`css.parser.cssModules`

Enables parsing of CSS Modules specific features.

`extends`

A list of paths to other JSON files, used to extends the current configuration.

`files`

The configuration of the filesystem

`files.ignore`

A list of Unix shell style patterns. Biome will ignore files/folders that will match these patterns.

`files.ignoreUnknown`

Tells Biome to not emit diagnostics when handling files that doesn’t know

`files.include`

A list of Unix shell style patterns. Biome will handle only those files/folders that will match these patterns.

`files.maxSize`

The maximum allowed size for source code files in bytes. Files above this limit will be ignored for performance reasons. Defaults to 1 MiB

`formatter`

The configuration of the formatter

Generic options applied to all files

`formatter.attributePosition`

The attribute position style in HTMLish languages. By default auto.

`formatter.formatWithErrors`

Stores whether formatting should be allowed to proceed if a given file has syntax errors

`formatter.ignore`

A list of Unix shell style patterns. The formatter will ignore files/folders that will match these patterns.

`formatter.include`

A list of Unix shell style patterns. The formatter will include files/folders that will match these patterns.

`formatter.indentSize`

The size of the indentation, 2 by default (deprecated, use indent-width)

`formatter.indentStyle`

The indent style.

`formatter.indentWidth`

The size of the indentation, 2 by default

`formatter.lineEnding`

The type of line ending.

`formatter.lineWidth`

What’s the max width of a line. Defaults to 80.

Validated value for the line_width formatter options

The allowed range of values is 1..=320

`javascript`

Specific configuration for the JavaScript language

A set of options applied to the JavaScript files

`javascript.formatter`

Formatting options

Formatting options specific to the JavaScript files

`javascript.formatter.arrowParentheses`

Whether to add non-necessary parentheses to arrow functions. Defaults to “always”.

`javascript.formatter.attributePosition`

The attribute position style in jsx elements. Defaults to auto.

`javascript.formatter.bracketSameLine`

Whether to hug the closing bracket of multiline HTML/JSX tags to the end of the last line, rather than being alone on the following line. Defaults to false.

`javascript.formatter.bracketSpacing`

Whether to insert spaces around brackets in object literals. Defaults to true.

`javascript.formatter.enabled`

Control the formatter for JavaScript (and its super languages) files.

`javascript.formatter.indentSize`

The size of the indentation applied to JavaScript (and its super languages) files. Default to 2.

`javascript.formatter.indentStyle`

The indent style applied to JavaScript (and its super languages) files.

`javascript.formatter.indentWidth`

The size of the indentation applied to JavaScript (and its super languages) files. Default to 2.

`javascript.formatter.jsxQuoteStyle`

The type of quotes used in JSX. Defaults to double.

`javascript.formatter.lineEnding`

The type of line ending applied to JavaScript (and its super languages) files.

`javascript.formatter.lineWidth`

What’s the max width of a line applied to JavaScript (and its super languages) files. Defaults to 80.

Validated value for the line_width formatter options

The allowed range of values is 1..=320

`javascript.formatter.quoteProperties`

When properties in objects are quoted. Defaults to asNeeded.

`javascript.formatter.quoteStyle`

The type of quotes used in JavaScript code. Defaults to double.

`javascript.formatter.semicolons`

Whether the formatter prints semicolons for all statements or only in for statements where it is necessary because of ASI.

`javascript.formatter.trailingComma`

Print trailing commas wherever possible in multi-line comma-separated syntactic structures. Defaults to “all”.

Print trailing commas wherever possible in multi-line comma-separated syntactic structures.

`javascript.formatter.trailingCommas`

Print trailing commas wherever possible in multi-line comma-separated syntactic structures. Defaults to “all”.

Print trailing commas wherever possible in multi-line comma-separated syntactic structures.

`javascript.globals`

A list of global bindings that should be ignored by the analyzers

If defined here, they should not emit diagnostics.

`javascript.jsxRuntime`

Indicates the type of runtime or transformation used for interpreting JSX.

`javascript.linter`

Linter options

Linter options specific to the JavaScript linter

`javascript.linter.enabled`

Control the linter for JavaScript (and its super languages) files.

`javascript.parser`

Parsing options

Options that changes how the JavaScript parser behaves

`javascript.parser.unsafeParameterDecoratorsEnabled`

It enables the experimental and unsafe parsing of parameter decorators

These decorators belong to an old proposal, and they are subject to change.

`json`

Specific configuration for the Json language

Options applied to JSON files

`json.formatter`

Formatting options

`json.formatter.enabled`

Control the formatter for JSON (and its super languages) files.

`json.formatter.indentSize`

The size of the indentation applied to JSON (and its super languages) files. Default to 2.

`json.formatter.indentStyle`

The indent style applied to JSON (and its super languages) files.

`json.formatter.indentWidth`

The size of the indentation applied to JSON (and its super languages) files. Default to 2.

`json.formatter.lineEnding`

The type of line ending applied to JSON (and its super languages) files.

`json.formatter.lineWidth`

What’s the max width of a line applied to JSON (and its super languages) files. Defaults to 80.

Validated value for the line_width formatter options

The allowed range of values is 1..=320

`json.formatter.trailingCommas`

Print trailing commas wherever possible in multi-line comma-separated syntactic structures. Defaults to “none”.

`json.linter`

Linting options

Linter options specific to the JSON linter

`json.linter.enabled`

Control the linter for JSON (and its super languages) files.

`json.parser`

Parsing options

Options that changes how the JSON parser behaves

`json.parser.allowComments`

Allow parsing comments in .json files

`json.parser.allowTrailingCommas`

Allow parsing trailing commas in .json files

`linter`

The configuration for the linter

`linter.enabled`

if false, it disables the feature and the linter won’t be executed. true by default

`linter.ignore`

A list of Unix shell style patterns. The formatter will ignore files/folders that will match these patterns.

`linter.include`

A list of Unix shell style patterns. The formatter will include files/folders that will match these patterns.

`linter.rules`

List of rules

A list of rules that belong to this group

`linter.rules.a11y.all`

It enables ALL rules for this group.

`linter.rules.a11y.noAccessKey`

Enforce that the accessKey attribute is not used on any HTML element.

`linter.rules.a11y.noAccessKey.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noAccessKey.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noAccessKey.options`

Rule’s options

`linter.rules.a11y.noAriaHiddenOnFocusable`

Enforce that aria-hidden=“true” is not set on focusable elements.

`linter.rules.a11y.noAriaHiddenOnFocusable.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noAriaHiddenOnFocusable.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noAriaHiddenOnFocusable.options`

Rule’s options

`linter.rules.a11y.noAriaUnsupportedElements`

Enforce that elements that do not support ARIA roles, states, and properties do not have those attributes.

`linter.rules.a11y.noAriaUnsupportedElements.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noAriaUnsupportedElements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noAriaUnsupportedElements.options`

Rule’s options

`linter.rules.a11y.noAutofocus`

Enforce that autoFocus prop is not used on elements.

`linter.rules.a11y.noAutofocus.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noAutofocus.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noAutofocus.options`

Rule’s options

`linter.rules.a11y.noBlankTarget`

Disallow target=“_blank” attribute without rel=“noreferrer”

`linter.rules.a11y.noBlankTarget.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noBlankTarget.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noBlankTarget.options`

Rule’s options

`linter.rules.a11y.noDistractingElements`

Enforces that no distracting elements are used.

`linter.rules.a11y.noDistractingElements.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noDistractingElements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noDistractingElements.options`

Rule’s options

`linter.rules.a11y.noHeaderScope`

The scope prop should be used only on <th> elements.

`linter.rules.a11y.noHeaderScope.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noHeaderScope.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noHeaderScope.options`

Rule’s options

`linter.rules.a11y.noInteractiveElementToNoninteractiveRole`

Enforce that non-interactive ARIA roles are not assigned to interactive HTML elements.

`linter.rules.a11y.noInteractiveElementToNoninteractiveRole.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noInteractiveElementToNoninteractiveRole.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noInteractiveElementToNoninteractiveRole.options`

Rule’s options

`linter.rules.a11y.noNoninteractiveElementToInteractiveRole`

Enforce that interactive ARIA roles are not assigned to non-interactive HTML elements.

`linter.rules.a11y.noNoninteractiveElementToInteractiveRole.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noNoninteractiveElementToInteractiveRole.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noNoninteractiveElementToInteractiveRole.options`

Rule’s options

`linter.rules.a11y.noNoninteractiveTabindex`

Enforce that tabIndex is not assigned to non-interactive HTML elements.

`linter.rules.a11y.noNoninteractiveTabindex.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noNoninteractiveTabindex.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noNoninteractiveTabindex.options`

Rule’s options

`linter.rules.a11y.noPositiveTabindex`

Prevent the usage of positive integers on tabIndex property

`linter.rules.a11y.noPositiveTabindex.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noPositiveTabindex.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noPositiveTabindex.options`

Rule’s options

`linter.rules.a11y.noRedundantAlt`

Enforce img alt prop does not contain the word “image”, “picture”, or “photo”.

`linter.rules.a11y.noRedundantAlt.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noRedundantAlt.options`

Rule’s options

`linter.rules.a11y.noRedundantRoles`

Enforce explicit role property is not the same as implicit/default role property on an element.

`linter.rules.a11y.noRedundantRoles.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.noRedundantRoles.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noRedundantRoles.options`

Rule’s options

`linter.rules.a11y.noSvgWithoutTitle`

Enforces the usage of the title element for the svg element.

`linter.rules.a11y.noSvgWithoutTitle.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.noSvgWithoutTitle.options`

Rule’s options

`linter.rules.a11y.recommended`

It enables the recommended rules for this group

`linter.rules.a11y.useAltText`

Enforce that all elements that require alternative text have meaningful information to relay back to the end user.

`linter.rules.a11y.useAltText.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useAltText.options`

Rule’s options

`linter.rules.a11y.useAnchorContent`

Enforce that anchors have content and that the content is accessible to screen readers.

`linter.rules.a11y.useAnchorContent.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.useAnchorContent.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useAnchorContent.options`

Rule’s options

`linter.rules.a11y.useAriaActivedescendantWithTabindex`

Enforce that tabIndex is assigned to non-interactive HTML elements with aria-activedescendant.

`linter.rules.a11y.useAriaActivedescendantWithTabindex.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.useAriaActivedescendantWithTabindex.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useAriaActivedescendantWithTabindex.options`

Rule’s options

`linter.rules.a11y.useAriaPropsForRole`

Enforce that elements with ARIA roles must have all required ARIA attributes for that role.

`linter.rules.a11y.useAriaPropsForRole.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useAriaPropsForRole.options`

Rule’s options

`linter.rules.a11y.useButtonType`

Enforces the usage of the attribute type for the element button

`linter.rules.a11y.useButtonType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useButtonType.options`

Rule’s options

`linter.rules.a11y.useHeadingContent`

Enforce that heading elements (h1, h2, etc.) have content and that the content is accessible to screen readers. Accessible means that it is not hidden using the aria-hidden prop.

`linter.rules.a11y.useHeadingContent.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useHeadingContent.options`

Rule’s options

`linter.rules.a11y.useHtmlLang`

Enforce that html element has lang attribute.

`linter.rules.a11y.useHtmlLang.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useHtmlLang.options`

Rule’s options

`linter.rules.a11y.useIframeTitle`

Enforces the usage of the attribute title for the element iframe.

`linter.rules.a11y.useIframeTitle.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useIframeTitle.options`

Rule’s options

`linter.rules.a11y.useKeyWithClickEvents`

Enforce onClick is accompanied by at least one of the following: onKeyUp, onKeyDown, onKeyPress.

`linter.rules.a11y.useKeyWithClickEvents.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useKeyWithClickEvents.options`

Rule’s options

`linter.rules.a11y.useKeyWithMouseEvents`

Enforce onMouseOver / onMouseOut are accompanied by onFocus / onBlur.

`linter.rules.a11y.useKeyWithMouseEvents.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useKeyWithMouseEvents.options`

Rule’s options

`linter.rules.a11y.useMediaCaption`

Enforces that audio and video elements must have a track for captions.

`linter.rules.a11y.useMediaCaption.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useMediaCaption.options`

Rule’s options

`linter.rules.a11y.useValidAnchor`

Enforce that all anchors are valid, and they are navigable elements.

`linter.rules.a11y.useValidAnchor.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useValidAnchor.options`

Rule’s options

`linter.rules.a11y.useValidAriaProps`

Ensures that ARIA properties aria-* are all valid.

`linter.rules.a11y.useValidAriaProps.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.useValidAriaProps.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useValidAriaProps.options`

Rule’s options

`linter.rules.a11y.useValidAriaRole`

Elements with ARIA roles must use a valid, non-abstract ARIA role.

`linter.rules.a11y.useValidAriaRole.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.a11y.useValidAriaRole.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useValidAriaRole.options`

Rule’s options

`linter.rules.a11y.useValidAriaValues`

Enforce that ARIA state and property values are valid.

`linter.rules.a11y.useValidAriaValues.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useValidAriaValues.options`

Rule’s options

`linter.rules.a11y.useValidLang`

Ensure that the attribute passed to the lang attribute is a correct ISO language and/or country.

`linter.rules.a11y.useValidLang.level`

The severity of the emitted diagnostics by the rule

`linter.rules.a11y.useValidLang.options`

Rule’s options

`linter.rules.all`

It enables ALL rules. The rules that belong to nursery won’t be enabled.

A list of rules that belong to this group

`linter.rules.complexity.all`

It enables ALL rules for this group.

`linter.rules.complexity.noBannedTypes`

Disallow primitive type aliases and misleading types.

`linter.rules.complexity.noBannedTypes.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noBannedTypes.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noBannedTypes.options`

Rule’s options

`linter.rules.complexity.noEmptyTypeParameters`

Disallow empty type parameters in type aliases and interfaces.

`linter.rules.complexity.noEmptyTypeParameters.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noEmptyTypeParameters.options`

Rule’s options

`linter.rules.complexity.noExcessiveCognitiveComplexity`

Disallow functions that exceed a given Cognitive Complexity score.

`linter.rules.complexity.noExcessiveCognitiveComplexity.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noExcessiveCognitiveComplexity.options`

Rule’s options

`linter.rules.complexity.noExcessiveNestedTestSuites`

This rule enforces a maximum depth to nested describe() in test files.

`linter.rules.complexity.noExcessiveNestedTestSuites.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noExcessiveNestedTestSuites.options`

Rule’s options

`linter.rules.complexity.noExtraBooleanCast`

Disallow unnecessary boolean casts

`linter.rules.complexity.noExtraBooleanCast.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noExtraBooleanCast.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noExtraBooleanCast.options`

Rule’s options

`linter.rules.complexity.noForEach`

Prefer for…of statement instead of Array.forEach.

`linter.rules.complexity.noForEach.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noForEach.options`

Rule’s options

`linter.rules.complexity.noMultipleSpacesInRegularExpressionLiterals`

Disallow unclear usage of consecutive space characters in regular expression literals

`linter.rules.complexity.noMultipleSpacesInRegularExpressionLiterals.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noMultipleSpacesInRegularExpressionLiterals.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noMultipleSpacesInRegularExpressionLiterals.options`

Rule’s options

`linter.rules.complexity.noStaticOnlyClass`

This rule reports when a class has no non-static members, such as for a class used exclusively as a static namespace.

`linter.rules.complexity.noStaticOnlyClass.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noStaticOnlyClass.options`

Rule’s options

`linter.rules.complexity.noThisInStatic`

Disallow this and super in static contexts.

`linter.rules.complexity.noThisInStatic.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noThisInStatic.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noThisInStatic.options`

Rule’s options

`linter.rules.complexity.noUselessCatch`

Disallow unnecessary catch clauses.

`linter.rules.complexity.noUselessCatch.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessCatch.options`

Rule’s options

`linter.rules.complexity.noUselessConstructor`

Disallow unnecessary constructors.

`linter.rules.complexity.noUselessConstructor.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessConstructor.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessConstructor.options`

Rule’s options

`linter.rules.complexity.noUselessEmptyExport`

Disallow empty exports that don’t change anything in a module file.

`linter.rules.complexity.noUselessEmptyExport.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessEmptyExport.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessEmptyExport.options`

Rule’s options

`linter.rules.complexity.noUselessFragments`

Disallow unnecessary fragments

`linter.rules.complexity.noUselessFragments.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessFragments.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessFragments.options`

Rule’s options

`linter.rules.complexity.noUselessLabel`

Disallow unnecessary labels.

`linter.rules.complexity.noUselessLabel.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessLabel.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessLabel.options`

Rule’s options

`linter.rules.complexity.noUselessLoneBlockStatements`

Disallow unnecessary nested block statements.

`linter.rules.complexity.noUselessLoneBlockStatements.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessLoneBlockStatements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessLoneBlockStatements.options`

Rule’s options

`linter.rules.complexity.noUselessRename`

Disallow renaming import, export, and destructured assignments to the same name.

`linter.rules.complexity.noUselessRename.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessRename.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessRename.options`

Rule’s options

`linter.rules.complexity.noUselessSwitchCase`

Disallow useless case in switch statements.

`linter.rules.complexity.noUselessSwitchCase.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessSwitchCase.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessSwitchCase.options`

Rule’s options

`linter.rules.complexity.noUselessTernary`

Disallow ternary operators when simpler alternatives exist.

`linter.rules.complexity.noUselessTernary.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessTernary.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessTernary.options`

Rule’s options

`linter.rules.complexity.noUselessThisAlias`

Disallow useless this aliasing.

`linter.rules.complexity.noUselessThisAlias.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessThisAlias.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessThisAlias.options`

Rule’s options

`linter.rules.complexity.noUselessTypeConstraint`

Disallow using any or unknown as type constraint.

`linter.rules.complexity.noUselessTypeConstraint.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.noUselessTypeConstraint.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noUselessTypeConstraint.options`

Rule’s options

`linter.rules.complexity.noVoid`

Disallow the use of void operators, which is not a familiar operator.

`linter.rules.complexity.noVoid.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noVoid.options`

Rule’s options

`linter.rules.complexity.noWith`

Disallow with statements in non-strict contexts.

`linter.rules.complexity.noWith.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.noWith.options`

Rule’s options

`linter.rules.complexity.recommended`

It enables the recommended rules for this group

`linter.rules.complexity.useArrowFunction`

Use arrow functions over function expressions.

`linter.rules.complexity.useArrowFunction.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useArrowFunction.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useArrowFunction.options`

Rule’s options

`linter.rules.complexity.useFlatMap`

Promotes the use of .flatMap() when map().flat() are used together.

`linter.rules.complexity.useFlatMap.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useFlatMap.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useFlatMap.options`

Rule’s options

`linter.rules.complexity.useLiteralKeys`

Enforce the usage of a literal access to properties over computed property access.

`linter.rules.complexity.useLiteralKeys.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useLiteralKeys.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useLiteralKeys.options`

Rule’s options

`linter.rules.complexity.useOptionalChain`

Enforce using concise optional chain instead of chained logical expressions.

`linter.rules.complexity.useOptionalChain.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useOptionalChain.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useOptionalChain.options`

Rule’s options

`linter.rules.complexity.useRegexLiterals`

Enforce the use of the regular expression literals instead of the RegExp constructor if possible.

`linter.rules.complexity.useRegexLiterals.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useRegexLiterals.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useRegexLiterals.options`

Rule’s options

`linter.rules.complexity.useSimpleNumberKeys`

Disallow number literal object member names which are not base10 or uses underscore as separator

`linter.rules.complexity.useSimpleNumberKeys.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useSimpleNumberKeys.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useSimpleNumberKeys.options`

Rule’s options

`linter.rules.complexity.useSimplifiedLogicExpression`

Discard redundant terms from logical expressions.

`linter.rules.complexity.useSimplifiedLogicExpression.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.complexity.useSimplifiedLogicExpression.level`

The severity of the emitted diagnostics by the rule

`linter.rules.complexity.useSimplifiedLogicExpression.options`

Rule’s options

A list of rules that belong to this group

`linter.rules.correctness.all`

It enables ALL rules for this group.

`linter.rules.correctness.noChildrenProp`

Prevent passing of children as props.

`linter.rules.correctness.noChildrenProp.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noChildrenProp.options`

Rule’s options

`linter.rules.correctness.noConstAssign`

Prevents from having const variables being re-assigned.

`linter.rules.correctness.noConstAssign.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noConstAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noConstAssign.options`

Rule’s options

`linter.rules.correctness.noConstantCondition`

Disallow constant expressions in conditions

`linter.rules.correctness.noConstantCondition.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noConstantCondition.options`

Rule’s options

`linter.rules.correctness.noConstantMathMinMaxClamp`

Disallow the use of Math.min and Math.max to clamp a value where the result itself is constant.

`linter.rules.correctness.noConstantMathMinMaxClamp.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noConstantMathMinMaxClamp.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noConstantMathMinMaxClamp.options`

Rule’s options

`linter.rules.correctness.noConstructorReturn`

Disallow returning a value from a constructor.

`linter.rules.correctness.noConstructorReturn.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noConstructorReturn.options`

Rule’s options

`linter.rules.correctness.noEmptyCharacterClassInRegex`

Disallow empty character classes in regular expression literals.

`linter.rules.correctness.noEmptyCharacterClassInRegex.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noEmptyCharacterClassInRegex.options`

Rule’s options

`linter.rules.correctness.noEmptyPattern`

Disallows empty destructuring patterns.

`linter.rules.correctness.noEmptyPattern.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noEmptyPattern.options`

Rule’s options

`linter.rules.correctness.noFlatMapIdentity`

Disallow to use unnecessary callback on flatMap.

`linter.rules.correctness.noFlatMapIdentity.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noFlatMapIdentity.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noFlatMapIdentity.options`

Rule’s options

`linter.rules.correctness.noGlobalObjectCalls`

Disallow calling global object properties as functions

`linter.rules.correctness.noGlobalObjectCalls.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noGlobalObjectCalls.options`

Rule’s options

`linter.rules.correctness.noInnerDeclarations`

Disallow function and var declarations that are accessible outside their block.

`linter.rules.correctness.noInnerDeclarations.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noInnerDeclarations.options`

Rule’s options

`linter.rules.correctness.noInvalidConstructorSuper`

Prevents the incorrect use of super() inside classes. It also checks whether a call super() is missing from classes that extends other constructors.

`linter.rules.correctness.noInvalidConstructorSuper.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noInvalidConstructorSuper.options`

Rule’s options

`linter.rules.correctness.noInvalidNewBuiltin`

Disallow new operators with global non-constructor functions.

`linter.rules.correctness.noInvalidNewBuiltin.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noInvalidNewBuiltin.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noInvalidNewBuiltin.options`

Rule’s options

`linter.rules.correctness.noInvalidUseBeforeDeclaration`

Disallow the use of variables and function parameters before their declaration

`linter.rules.correctness.noInvalidUseBeforeDeclaration.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noInvalidUseBeforeDeclaration.options`

Rule’s options

`linter.rules.correctness.noNewSymbol`

Disallow new operators with the Symbol object.

`linter.rules.correctness.noNewSymbol.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noNewSymbol.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noNewSymbol.options`

Rule’s options

`linter.rules.correctness.noNodejsModules`

Forbid the use of Node.js builtin modules.

`linter.rules.correctness.noNodejsModules.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noNodejsModules.options`

Rule’s options

`linter.rules.correctness.noNonoctalDecimalEscape`

Disallow \8 and \9 escape sequences in string literals.

`linter.rules.correctness.noNonoctalDecimalEscape.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noNonoctalDecimalEscape.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noNonoctalDecimalEscape.options`

Rule’s options

`linter.rules.correctness.noPrecisionLoss`

Disallow literal numbers that lose precision

`linter.rules.correctness.noPrecisionLoss.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noPrecisionLoss.options`

Rule’s options

`linter.rules.correctness.noRenderReturnValue`

Prevent the usage of the return value of React.render.

`linter.rules.correctness.noRenderReturnValue.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noRenderReturnValue.options`

Rule’s options

`linter.rules.correctness.noSelfAssign`

Disallow assignments where both sides are exactly the same.

`linter.rules.correctness.noSelfAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noSelfAssign.options`

Rule’s options

`linter.rules.correctness.noSetterReturn`

Disallow returning a value from a setter

`linter.rules.correctness.noSetterReturn.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noSetterReturn.options`

Rule’s options

`linter.rules.correctness.noStringCaseMismatch`

Disallow comparison of expressions modifying the string case with non-compliant value.

`linter.rules.correctness.noStringCaseMismatch.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noStringCaseMismatch.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noStringCaseMismatch.options`

Rule’s options

`linter.rules.correctness.noSwitchDeclarations`

Disallow lexical declarations in switch clauses.

`linter.rules.correctness.noSwitchDeclarations.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noSwitchDeclarations.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noSwitchDeclarations.options`

Rule’s options

`linter.rules.correctness.noUndeclaredVariables`

Prevents the usage of variables that haven’t been declared inside the document.

`linter.rules.correctness.noUndeclaredVariables.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUndeclaredVariables.options`

Rule’s options

`linter.rules.correctness.noUnnecessaryContinue`

Avoid using unnecessary continue.

`linter.rules.correctness.noUnnecessaryContinue.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noUnnecessaryContinue.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnnecessaryContinue.options`

Rule’s options

`linter.rules.correctness.noUnreachable`

Disallow unreachable code

`linter.rules.correctness.noUnreachable.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnreachable.options`

Rule’s options

`linter.rules.correctness.noUnreachableSuper`

Ensures the super() constructor is called exactly once on every code path in a class constructor before this is accessed if the class has a superclass

`linter.rules.correctness.noUnreachableSuper.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnreachableSuper.options`

Rule’s options

`linter.rules.correctness.noUnsafeFinally`

Disallow control flow statements in finally blocks.

`linter.rules.correctness.noUnsafeFinally.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnsafeFinally.options`

Rule’s options

`linter.rules.correctness.noUnsafeOptionalChaining`

Disallow the use of optional chaining in contexts where the undefined value is not allowed.

`linter.rules.correctness.noUnsafeOptionalChaining.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnsafeOptionalChaining.options`

Rule’s options

`linter.rules.correctness.noUnusedImports`

Disallow unused imports.

`linter.rules.correctness.noUnusedImports.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noUnusedImports.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnusedImports.options`

Rule’s options

`linter.rules.correctness.noUnusedLabels`

Disallow unused labels.

`linter.rules.correctness.noUnusedLabels.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noUnusedLabels.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnusedLabels.options`

Rule’s options

`linter.rules.correctness.noUnusedPrivateClassMembers`

Disallow unused private class members

`linter.rules.correctness.noUnusedPrivateClassMembers.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noUnusedPrivateClassMembers.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnusedPrivateClassMembers.options`

Rule’s options

`linter.rules.correctness.noUnusedVariables`

Disallow unused variables.

`linter.rules.correctness.noUnusedVariables.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noUnusedVariables.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noUnusedVariables.options`

Rule’s options

`linter.rules.correctness.noVoidElementsWithChildren`

This rules prevents void elements (AKA self-closing elements) from having children.

`linter.rules.correctness.noVoidElementsWithChildren.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.noVoidElementsWithChildren.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noVoidElementsWithChildren.options`

Rule’s options

`linter.rules.correctness.noVoidTypeReturn`

Disallow returning a value from a function with the return type ‘void’

`linter.rules.correctness.noVoidTypeReturn.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.noVoidTypeReturn.options`

Rule’s options

`linter.rules.correctness.recommended`

It enables the recommended rules for this group

`linter.rules.correctness.useArrayLiterals`

Disallow Array constructors.

`linter.rules.correctness.useArrayLiterals.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.useArrayLiterals.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useArrayLiterals.options`

Rule’s options

`linter.rules.correctness.useExhaustiveDependencies`

Enforce all dependencies are correctly specified in a React hook.

`linter.rules.correctness.useExhaustiveDependencies.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useExhaustiveDependencies.options`

Rule’s options

`linter.rules.correctness.useHookAtTopLevel`

Enforce that all React hooks are being called from the Top Level component functions.

`linter.rules.correctness.useHookAtTopLevel.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useHookAtTopLevel.options`

Rule’s options

`linter.rules.correctness.useIsNan`

Require calls to isNaN() when checking for NaN.

`linter.rules.correctness.useIsNan.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.correctness.useIsNan.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useIsNan.options`

Rule’s options

`linter.rules.correctness.useJsxKeyInIterable`

Disallow missing key props in iterators/collection literals.

`linter.rules.correctness.useJsxKeyInIterable.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useJsxKeyInIterable.options`

Rule’s options

`linter.rules.correctness.useValidForDirection`

Enforce “for” loop update clause moving the counter in the right direction.

`linter.rules.correctness.useValidForDirection.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useValidForDirection.options`

Rule’s options

`linter.rules.correctness.useYield`

Require generator functions to contain yield.

`linter.rules.correctness.useYield.level`

The severity of the emitted diagnostics by the rule

`linter.rules.correctness.useYield.options`

Rule’s options

A list of rules that belong to this group

`linter.rules.nursery.all`

It enables ALL rules for this group.

`linter.rules.nursery.noConsole`

Disallow the use of console.

`linter.rules.nursery.noConsole.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.noConsole.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noConsole.options`

Rule’s options

`linter.rules.nursery.noDoneCallback`

Disallow using a callback in asynchronous tests and hooks.

`linter.rules.nursery.noDoneCallback.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noDoneCallback.options`

Rule’s options

`linter.rules.nursery.noDuplicateAtImportRules`

Disallow duplicate @import rules.

`linter.rules.nursery.noDuplicateAtImportRules.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noDuplicateAtImportRules.options`

Rule’s options

`linter.rules.nursery.noDuplicateElseIf`

Disallow duplicate conditions in if-else-if chains

`linter.rules.nursery.noDuplicateElseIf.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noDuplicateElseIf.options`

Rule’s options

`linter.rules.nursery.noDuplicateFontNames`

Disallow duplicate names within font families.

`linter.rules.nursery.noDuplicateFontNames.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noDuplicateFontNames.options`

Rule’s options

`linter.rules.nursery.noDuplicateJsonKeys`

Disallow two keys with the same name inside a JSON object.

`linter.rules.nursery.noDuplicateJsonKeys.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noDuplicateJsonKeys.options`

Rule’s options

`linter.rules.nursery.noDuplicateSelectorsKeyframeBlock`

Disallow duplicate selectors within keyframe blocks.

`linter.rules.nursery.noDuplicateSelectorsKeyframeBlock.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noDuplicateSelectorsKeyframeBlock.options`

Rule’s options

`linter.rules.nursery.noEmptyBlock`

Disallow CSS empty blocks.

`linter.rules.nursery.noEmptyBlock.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noEmptyBlock.options`

Rule’s options

`linter.rules.nursery.noEvolvingTypes`

Disallow variables from evolving into any type through reassignments.

`linter.rules.nursery.noEvolvingTypes.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noEvolvingTypes.options`

Rule’s options

`linter.rules.nursery.noImportantInKeyframe`

Disallow invalid !important within keyframe declarations

`linter.rules.nursery.noImportantInKeyframe.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noImportantInKeyframe.options`

Rule’s options

`linter.rules.nursery.noInvalidPositionAtImportRule`

Disallow the use of @import at-rules in invalid positions.

`linter.rules.nursery.noInvalidPositionAtImportRule.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noInvalidPositionAtImportRule.options`

Rule’s options

`linter.rules.nursery.noLabelWithoutControl`

Enforce that a label element or component has a text label and an associated input.

`linter.rules.nursery.noLabelWithoutControl.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noLabelWithoutControl.options`

Rule’s options

`linter.rules.nursery.noMisplacedAssertion`

Checks that the assertion function, for example expect, is placed inside an it() function call.

`linter.rules.nursery.noMisplacedAssertion.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noMisplacedAssertion.options`

Rule’s options

`linter.rules.nursery.noReactSpecificProps`

Prevents React-specific JSX properties from being used.

`linter.rules.nursery.noReactSpecificProps.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.noReactSpecificProps.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noReactSpecificProps.options`

Rule’s options

`linter.rules.nursery.noRestrictedImports`

Disallow specified modules when loaded by import or require.

`linter.rules.nursery.noRestrictedImports.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noRestrictedImports.options`

Rule’s options

`linter.rules.nursery.noUndeclaredDependencies`

Disallow the use of dependencies that aren’t specified in the package.json.

`linter.rules.nursery.noUndeclaredDependencies.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUndeclaredDependencies.options`

Rule’s options

`linter.rules.nursery.noUnknownFunction`

Disallow unknown CSS value functions.

`linter.rules.nursery.noUnknownFunction.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnknownFunction.options`

Rule’s options

`linter.rules.nursery.noUnknownMediaFeatureName`

Disallow unknown media feature names.

`linter.rules.nursery.noUnknownMediaFeatureName.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnknownMediaFeatureName.options`

Rule’s options

`linter.rules.nursery.noUnknownProperty`

Disallow unknown properties.

`linter.rules.nursery.noUnknownProperty.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnknownProperty.options`

Rule’s options

`linter.rules.nursery.noUnknownSelectorPseudoElement`

Disallow unknown pseudo-element selectors.

`linter.rules.nursery.noUnknownSelectorPseudoElement.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnknownSelectorPseudoElement.options`

Rule’s options

`linter.rules.nursery.noUnknownUnit`

Disallow unknown CSS units.

`linter.rules.nursery.noUnknownUnit.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnknownUnit.options`

Rule’s options

`linter.rules.nursery.noUnmatchableAnbSelector`

Disallow unmatchable An+B selectors.

`linter.rules.nursery.noUnmatchableAnbSelector.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnmatchableAnbSelector.options`

Rule’s options

`linter.rules.nursery.noUnusedFunctionParameters`

Disallow unused function parameters.

`linter.rules.nursery.noUnusedFunctionParameters.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.noUnusedFunctionParameters.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUnusedFunctionParameters.options`

Rule’s options

`linter.rules.nursery.noUselessStringConcat`

Disallow unnecessary concatenation of string or template literals.

`linter.rules.nursery.noUselessStringConcat.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.noUselessStringConcat.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUselessStringConcat.options`

Rule’s options

`linter.rules.nursery.noUselessUndefinedInitialization`

Disallow initializing variables to undefined.

`linter.rules.nursery.noUselessUndefinedInitialization.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.noUselessUndefinedInitialization.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noUselessUndefinedInitialization.options`

Rule’s options

`linter.rules.nursery.noYodaExpression`

Disallow the use of yoda expressions.

`linter.rules.nursery.noYodaExpression.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.noYodaExpression.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.noYodaExpression.options`

Rule’s options

`linter.rules.nursery.recommended`

It enables the recommended rules for this group

`linter.rules.nursery.useAdjacentOverloadSignatures`

Disallow the use of overload signatures that are not next to each other.

`linter.rules.nursery.useAdjacentOverloadSignatures.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useAdjacentOverloadSignatures.options`

Rule’s options

`linter.rules.nursery.useConsistentBuiltinInstantiation`

Enforce the use of new for all builtins, except String, Number, Boolean, Symbol and BigInt.

`linter.rules.nursery.useConsistentBuiltinInstantiation.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useConsistentBuiltinInstantiation.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useConsistentBuiltinInstantiation.options`

Rule’s options

`linter.rules.nursery.useDateNow`

Use Date.now() to get the number of milliseconds since the Unix Epoch.

`linter.rules.nursery.useDateNow.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useDateNow.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useDateNow.options`

Rule’s options

`linter.rules.nursery.useDefaultSwitchClause`

Require the default clause in switch statements.

`linter.rules.nursery.useDefaultSwitchClause.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useDefaultSwitchClause.options`

Rule’s options

`linter.rules.nursery.useErrorMessage`

Enforce passing a message value when creating a built-in error.

`linter.rules.nursery.useErrorMessage.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useErrorMessage.options`

Rule’s options

`linter.rules.nursery.useExplicitLengthCheck`

Enforce explicitly comparing the length, size, byteLength or byteOffset property of a value.

`linter.rules.nursery.useExplicitLengthCheck.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useExplicitLengthCheck.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useExplicitLengthCheck.options`

Rule’s options

`linter.rules.nursery.useFocusableInteractive`

Elements with an interactive role and interaction handlers must be focusable.

`linter.rules.nursery.useFocusableInteractive.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useFocusableInteractive.options`

Rule’s options

`linter.rules.nursery.useGenericFontNames`

Disallow a missing generic family keyword within font families.

`linter.rules.nursery.useGenericFontNames.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useGenericFontNames.options`

Rule’s options

`linter.rules.nursery.useImportExtensions`

Enforce file extensions for relative imports.

`linter.rules.nursery.useImportExtensions.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useImportExtensions.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useImportExtensions.options`

Rule’s options

`linter.rules.nursery.useImportRestrictions`

Disallows package private imports.

`linter.rules.nursery.useImportRestrictions.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useImportRestrictions.options`

Rule’s options

`linter.rules.nursery.useNumberToFixedDigitsArgument`

Enforce using the digits argument with Number#toFixed().

`linter.rules.nursery.useNumberToFixedDigitsArgument.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useNumberToFixedDigitsArgument.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useNumberToFixedDigitsArgument.options`

Rule’s options

`linter.rules.nursery.useSemanticElements`

It detects the use of role attributes in JSX elements and suggests using semantic elements instead.

`linter.rules.nursery.useSemanticElements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useSemanticElements.options`

Rule’s options

`linter.rules.nursery.useSortedClasses`

Enforce the sorting of CSS utility classes.

`linter.rules.nursery.useSortedClasses.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useSortedClasses.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useSortedClasses.options`

Rule’s options

`linter.rules.nursery.useThrowNewError`

Require new when throwing an error.

`linter.rules.nursery.useThrowNewError.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.nursery.useThrowNewError.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useThrowNewError.options`

Rule’s options

`linter.rules.nursery.useThrowOnlyError`

Disallow throwing non-Error values.

`linter.rules.nursery.useThrowOnlyError.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useThrowOnlyError.options`

Rule’s options

`linter.rules.nursery.useTopLevelRegex`

Require regex literals to be declared at the top level.

`linter.rules.nursery.useTopLevelRegex.level`

The severity of the emitted diagnostics by the rule

`linter.rules.nursery.useTopLevelRegex.options`

Rule’s options

A list of rules that belong to this group

`linter.rules.performance.all`

It enables ALL rules for this group.

`linter.rules.performance.noAccumulatingSpread`

Disallow the use of spread (…) syntax on accumulators.

`linter.rules.performance.noAccumulatingSpread.level`

The severity of the emitted diagnostics by the rule

`linter.rules.performance.noAccumulatingSpread.options`

Rule’s options

`linter.rules.performance.noBarrelFile`

Disallow the use of barrel file.

`linter.rules.performance.noBarrelFile.level`

The severity of the emitted diagnostics by the rule

`linter.rules.performance.noBarrelFile.options`

Rule’s options

`linter.rules.performance.noDelete`

Disallow the use of the delete operator.

`linter.rules.performance.noDelete.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.performance.noDelete.level`

The severity of the emitted diagnostics by the rule

`linter.rules.performance.noDelete.options`

Rule’s options

`linter.rules.performance.noReExportAll`

Avoid re-export all.

`linter.rules.performance.noReExportAll.level`

The severity of the emitted diagnostics by the rule

`linter.rules.performance.noReExportAll.options`

Rule’s options

`linter.rules.performance.recommended`

It enables the recommended rules for this group

`linter.rules.recommended`

It enables the lint rules recommended by Biome. true by default.

A list of rules that belong to this group

`linter.rules.security.all`

It enables ALL rules for this group.

`linter.rules.security.noDangerouslySetInnerHtml`

Prevent the usage of dangerous JSX props

`linter.rules.security.noDangerouslySetInnerHtml.level`

The severity of the emitted diagnostics by the rule

`linter.rules.security.noDangerouslySetInnerHtml.options`

Rule’s options

`linter.rules.security.noDangerouslySetInnerHtmlWithChildren`

Report when a DOM element or a component uses both children and dangerouslySetInnerHTML prop.

`linter.rules.security.noDangerouslySetInnerHtmlWithChildren.level`

The severity of the emitted diagnostics by the rule

`linter.rules.security.noDangerouslySetInnerHtmlWithChildren.options`

Rule’s options

`linter.rules.security.noGlobalEval`

Disallow the use of global eval().

`linter.rules.security.noGlobalEval.level`

The severity of the emitted diagnostics by the rule

`linter.rules.security.noGlobalEval.options`

Rule’s options

`linter.rules.security.recommended`

It enables the recommended rules for this group

A list of rules that belong to this group

`linter.rules.style.all`

It enables ALL rules for this group.

`linter.rules.style.noArguments`

Disallow the use of arguments.

`linter.rules.style.noArguments.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noArguments.options`

Rule’s options

`linter.rules.style.noCommaOperator`

Disallow comma operator.

`linter.rules.style.noCommaOperator.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noCommaOperator.options`

Rule’s options

`linter.rules.style.noDefaultExport`

Disallow default exports.

`linter.rules.style.noDefaultExport.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noDefaultExport.options`

Rule’s options

`linter.rules.style.noImplicitBoolean`

Disallow implicit true values on JSX boolean attributes

`linter.rules.style.noImplicitBoolean.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noImplicitBoolean.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noImplicitBoolean.options`

Rule’s options

`linter.rules.style.noInferrableTypes`

Disallow type annotations for variables, parameters, and class properties initialized with a literal expression.

`linter.rules.style.noInferrableTypes.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noInferrableTypes.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noInferrableTypes.options`

Rule’s options

`linter.rules.style.noNamespace`

Disallow the use of TypeScript’s namespaces.

`linter.rules.style.noNamespace.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noNamespace.options`

Rule’s options

`linter.rules.style.noNamespaceImport`

Disallow the use of namespace imports.

`linter.rules.style.noNamespaceImport.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noNamespaceImport.options`

Rule’s options

`linter.rules.style.noNegationElse`

Disallow negation in the condition of an if statement if it has an else clause.

`linter.rules.style.noNegationElse.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noNegationElse.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noNegationElse.options`

Rule’s options

`linter.rules.style.noNonNullAssertion`

Disallow non-null assertions using the ! postfix operator.

`linter.rules.style.noNonNullAssertion.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noNonNullAssertion.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noNonNullAssertion.options`

Rule’s options

`linter.rules.style.noParameterAssign`

Disallow reassigning function parameters.

`linter.rules.style.noParameterAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noParameterAssign.options`

Rule’s options

`linter.rules.style.noParameterProperties`

Disallow the use of parameter properties in class constructors.

`linter.rules.style.noParameterProperties.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noParameterProperties.options`

Rule’s options

`linter.rules.style.noRestrictedGlobals`

This rule allows you to specify global variable names that you don’t want to use in your application.

`linter.rules.style.noRestrictedGlobals.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noRestrictedGlobals.options`

Rule’s options

`linter.rules.style.noShoutyConstants`

Disallow the use of constants which its value is the upper-case version of its name.

`linter.rules.style.noShoutyConstants.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noShoutyConstants.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noShoutyConstants.options`

Rule’s options

`linter.rules.style.noUnusedTemplateLiteral`

Disallow template literals if interpolation and special-character handling are not needed

`linter.rules.style.noUnusedTemplateLiteral.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noUnusedTemplateLiteral.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noUnusedTemplateLiteral.options`

Rule’s options

`linter.rules.style.noUselessElse`

Disallow else block when the if block breaks early.

`linter.rules.style.noUselessElse.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noUselessElse.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noUselessElse.options`

Rule’s options

`linter.rules.style.noVar`

Disallow the use of var

`linter.rules.style.noVar.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.noVar.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.noVar.options`

Rule’s options

`linter.rules.style.recommended`

It enables the recommended rules for this group

`linter.rules.style.useAsConstAssertion`

Enforce the use of as const over literal type and type annotation.

`linter.rules.style.useAsConstAssertion.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useAsConstAssertion.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useAsConstAssertion.options`

Rule’s options

`linter.rules.style.useBlockStatements`

Requires following curly brace conventions.

`linter.rules.style.useBlockStatements.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useBlockStatements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useBlockStatements.options`

Rule’s options

`linter.rules.style.useCollapsedElseIf`

Enforce using else if instead of nested if in else clauses.

`linter.rules.style.useCollapsedElseIf.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useCollapsedElseIf.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useCollapsedElseIf.options`

Rule’s options

`linter.rules.style.useConsistentArrayType`

Require consistently using either T[] or Array<T>

`linter.rules.style.useConsistentArrayType.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useConsistentArrayType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useConsistentArrayType.options`

Rule’s options

`linter.rules.style.useConst`

Require const declarations for variables that are only assigned once.

`linter.rules.style.useConst.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useConst.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useConst.options`

Rule’s options

`linter.rules.style.useDefaultParameterLast`

Enforce default function parameters and optional function parameters to be last.

`linter.rules.style.useDefaultParameterLast.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useDefaultParameterLast.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useDefaultParameterLast.options`

Rule’s options

`linter.rules.style.useEnumInitializers`

Require that each enum member value be explicitly initialized.

`linter.rules.style.useEnumInitializers.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useEnumInitializers.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useEnumInitializers.options`

Rule’s options

`linter.rules.style.useExponentiationOperator`

Disallow the use of Math.pow in favor of the ** operator.

`linter.rules.style.useExponentiationOperator.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useExponentiationOperator.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useExponentiationOperator.options`

Rule’s options

`linter.rules.style.useExportType`

Promotes the use of export type for types.

`linter.rules.style.useExportType.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useExportType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useExportType.options`

Rule’s options

`linter.rules.style.useFilenamingConvention`

Enforce naming conventions for JavaScript and TypeScript filenames.

`linter.rules.style.useFilenamingConvention.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useFilenamingConvention.options`

Rule’s options

`linter.rules.style.useForOf`

This rule recommends a for-of loop when in a for loop, the index used to extract an item from the iterated array.

`linter.rules.style.useForOf.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useForOf.options`

Rule’s options

`linter.rules.style.useFragmentSyntax`

This rule enforces the use of <>…</> over <Fragment>…</Fragment>.

`linter.rules.style.useFragmentSyntax.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useFragmentSyntax.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useFragmentSyntax.options`

Rule’s options

`linter.rules.style.useImportType`

Promotes the use of import type for types.

`linter.rules.style.useImportType.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useImportType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useImportType.options`

Rule’s options

`linter.rules.style.useLiteralEnumMembers`

Require all enum members to be literal values.

`linter.rules.style.useLiteralEnumMembers.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useLiteralEnumMembers.options`

Rule’s options

`linter.rules.style.useNamingConvention`

Enforce naming conventions for everything across a codebase.

`linter.rules.style.useNamingConvention.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useNamingConvention.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useNamingConvention.options`

Rule’s options

`linter.rules.style.useNodeAssertStrict`

Promotes the usage of node:assert /strict over node:assert .

`linter.rules.style.useNodeAssertStrict.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useNodeAssertStrict.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useNodeAssertStrict.options`

Rule’s options

`linter.rules.style.useNodejsImportProtocol`

Enforces using the node: protocol for Node.js builtin modules.

`linter.rules.style.useNodejsImportProtocol.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useNodejsImportProtocol.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useNodejsImportProtocol.options`

Rule’s options

`linter.rules.style.useNumberNamespace`

Use the Number properties instead of global ones.

`linter.rules.style.useNumberNamespace.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useNumberNamespace.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useNumberNamespace.options`

Rule’s options

`linter.rules.style.useNumericLiterals`

Disallow parseInt() and Number.parseInt() in favor of binary, octal, and hexadecimal literals

`linter.rules.style.useNumericLiterals.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useNumericLiterals.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useNumericLiterals.options`

Rule’s options

`linter.rules.style.useSelfClosingElements`

Prevent extra closing tags for components without children

`linter.rules.style.useSelfClosingElements.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useSelfClosingElements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useSelfClosingElements.options`

Rule’s options

`linter.rules.style.useShorthandArrayType`

When expressing array types, this rule promotes the usage of T[] shorthand instead of Array<T>.

`linter.rules.style.useShorthandArrayType.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useShorthandArrayType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useShorthandArrayType.options`

Rule’s options

`linter.rules.style.useShorthandAssign`

Require assignment operator shorthand where possible.

`linter.rules.style.useShorthandAssign.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useShorthandAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useShorthandAssign.options`

Rule’s options

`linter.rules.style.useShorthandFunctionType`

Enforce using function types instead of object type with call signatures.

`linter.rules.style.useShorthandFunctionType.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useShorthandFunctionType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useShorthandFunctionType.options`

Rule’s options

`linter.rules.style.useSingleCaseStatement`

Enforces switch clauses have a single statement, emits a quick fix wrapping the statements in a block.

`linter.rules.style.useSingleCaseStatement.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useSingleCaseStatement.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useSingleCaseStatement.options`

Rule’s options

`linter.rules.style.useSingleVarDeclarator`

Disallow multiple variable declarations in the same variable statement

`linter.rules.style.useSingleVarDeclarator.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useSingleVarDeclarator.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useSingleVarDeclarator.options`

Rule’s options

`linter.rules.style.useTemplate`

Prefer template literals over string concatenation.

`linter.rules.style.useTemplate.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useTemplate.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useTemplate.options`

Rule’s options

`linter.rules.style.useWhile`

Enforce the use of while loops instead of for loops when the initializer and update expressions are not needed.

`linter.rules.style.useWhile.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.style.useWhile.level`

The severity of the emitted diagnostics by the rule

`linter.rules.style.useWhile.options`

Rule’s options

A list of rules that belong to this group

`linter.rules.suspicious.all`

It enables ALL rules for this group.

`linter.rules.suspicious.noApproximativeNumericConstant`

Use standard constants instead of approximated literals.

`linter.rules.suspicious.noApproximativeNumericConstant.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noApproximativeNumericConstant.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noApproximativeNumericConstant.options`

Rule’s options

`linter.rules.suspicious.noArrayIndexKey`

Discourage the usage of Array index in keys.

`linter.rules.suspicious.noArrayIndexKey.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noArrayIndexKey.options`

Rule’s options

`linter.rules.suspicious.noAssignInExpressions`

Disallow assignments in expressions.

`linter.rules.suspicious.noAssignInExpressions.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noAssignInExpressions.options`

Rule’s options

`linter.rules.suspicious.noAsyncPromiseExecutor`

Disallows using an async function as a Promise executor.

`linter.rules.suspicious.noAsyncPromiseExecutor.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noAsyncPromiseExecutor.options`

Rule’s options

`linter.rules.suspicious.noCatchAssign`

Disallow reassigning exceptions in catch clauses.

`linter.rules.suspicious.noCatchAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noCatchAssign.options`

Rule’s options

`linter.rules.suspicious.noClassAssign`

Disallow reassigning class members.

`linter.rules.suspicious.noClassAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noClassAssign.options`

Rule’s options

`linter.rules.suspicious.noCommentText`

Prevent comments from being inserted as text nodes

`linter.rules.suspicious.noCommentText.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noCommentText.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noCommentText.options`

Rule’s options

`linter.rules.suspicious.noCompareNegZero`

Disallow comparing against -0

`linter.rules.suspicious.noCompareNegZero.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noCompareNegZero.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noCompareNegZero.options`

Rule’s options

`linter.rules.suspicious.noConfusingLabels`

Disallow labeled statements that are not loops.

`linter.rules.suspicious.noConfusingLabels.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noConfusingLabels.options`

Rule’s options

`linter.rules.suspicious.noConfusingVoidType`

Disallow void type outside of generic or return types.

`linter.rules.suspicious.noConfusingVoidType.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noConfusingVoidType.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noConfusingVoidType.options`

Rule’s options

`linter.rules.suspicious.noConsoleLog`

Disallow the use of console.log

`linter.rules.suspicious.noConsoleLog.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noConsoleLog.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noConsoleLog.options`

Rule’s options

`linter.rules.suspicious.noConstEnum`

Disallow TypeScript const enum

`linter.rules.suspicious.noConstEnum.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noConstEnum.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noConstEnum.options`

Rule’s options

`linter.rules.suspicious.noControlCharactersInRegex`

Prevents from having control characters and some escape sequences that match control characters in regular expressions.

`linter.rules.suspicious.noControlCharactersInRegex.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noControlCharactersInRegex.options`

Rule’s options

`linter.rules.suspicious.noDebugger`

Disallow the use of debugger

`linter.rules.suspicious.noDebugger.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noDebugger.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDebugger.options`

Rule’s options

`linter.rules.suspicious.noDoubleEquals`

Require the use of === and !==

`linter.rules.suspicious.noDoubleEquals.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noDoubleEquals.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDoubleEquals.options`

Rule’s options

`linter.rules.suspicious.noDuplicateCase`

Disallow duplicate case labels.

`linter.rules.suspicious.noDuplicateCase.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDuplicateCase.options`

Rule’s options

`linter.rules.suspicious.noDuplicateClassMembers`

Disallow duplicate class members.

`linter.rules.suspicious.noDuplicateClassMembers.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDuplicateClassMembers.options`

Rule’s options

`linter.rules.suspicious.noDuplicateJsxProps`

Prevents JSX properties to be assigned multiple times.

`linter.rules.suspicious.noDuplicateJsxProps.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDuplicateJsxProps.options`

Rule’s options

`linter.rules.suspicious.noDuplicateObjectKeys`

Prevents object literals having more than one property declaration for the same name.

`linter.rules.suspicious.noDuplicateObjectKeys.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noDuplicateObjectKeys.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDuplicateObjectKeys.options`

Rule’s options

`linter.rules.suspicious.noDuplicateParameters`

Disallow duplicate function parameter name.

`linter.rules.suspicious.noDuplicateParameters.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDuplicateParameters.options`

Rule’s options

`linter.rules.suspicious.noDuplicateTestHooks`

A describe block should not contain duplicate hooks.

`linter.rules.suspicious.noDuplicateTestHooks.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noDuplicateTestHooks.options`

Rule’s options

`linter.rules.suspicious.noEmptyBlockStatements`

Disallow empty block statements and static blocks.

`linter.rules.suspicious.noEmptyBlockStatements.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noEmptyBlockStatements.options`

Rule’s options

`linter.rules.suspicious.noEmptyInterface`

Disallow the declaration of empty interfaces.

`linter.rules.suspicious.noEmptyInterface.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noEmptyInterface.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noEmptyInterface.options`

Rule’s options

`linter.rules.suspicious.noExplicitAny`

Disallow the any type usage.

`linter.rules.suspicious.noExplicitAny.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noExplicitAny.options`

Rule’s options

`linter.rules.suspicious.noExportsInTest`

Disallow using export or module.exports in files containing tests

`linter.rules.suspicious.noExportsInTest.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noExportsInTest.options`

Rule’s options

`linter.rules.suspicious.noExtraNonNullAssertion`

Prevents the wrong usage of the non-null assertion operator (!) in TypeScript files.

`linter.rules.suspicious.noExtraNonNullAssertion.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noExtraNonNullAssertion.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noExtraNonNullAssertion.options`

Rule’s options

`linter.rules.suspicious.noFallthroughSwitchClause`

Disallow fallthrough of switch clauses.

`linter.rules.suspicious.noFallthroughSwitchClause.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noFallthroughSwitchClause.options`

Rule’s options

`linter.rules.suspicious.noFocusedTests`

Disallow focused tests.

`linter.rules.suspicious.noFocusedTests.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noFocusedTests.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noFocusedTests.options`

Rule’s options

`linter.rules.suspicious.noFunctionAssign`

Disallow reassigning function declarations.

`linter.rules.suspicious.noFunctionAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noFunctionAssign.options`

Rule’s options

`linter.rules.suspicious.noGlobalAssign`

Disallow assignments to native objects and read-only global variables.

`linter.rules.suspicious.noGlobalAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noGlobalAssign.options`

Rule’s options

`linter.rules.suspicious.noGlobalIsFinite`

Use Number.isFinite instead of global isFinite.

`linter.rules.suspicious.noGlobalIsFinite.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noGlobalIsFinite.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noGlobalIsFinite.options`

Rule’s options

`linter.rules.suspicious.noGlobalIsNan`

Use Number.isNaN instead of global isNaN.

`linter.rules.suspicious.noGlobalIsNan.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noGlobalIsNan.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noGlobalIsNan.options`

Rule’s options

`linter.rules.suspicious.noImplicitAnyLet`

Disallow use of implicit any type on variable declarations.

`linter.rules.suspicious.noImplicitAnyLet.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noImplicitAnyLet.options`

Rule’s options

`linter.rules.suspicious.noImportAssign`

Disallow assigning to imported bindings

`linter.rules.suspicious.noImportAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noImportAssign.options`

Rule’s options

`linter.rules.suspicious.noLabelVar`

Disallow labels that share a name with a variable

`linter.rules.suspicious.noLabelVar.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noLabelVar.options`

Rule’s options

`linter.rules.suspicious.noMisleadingCharacterClass`

Disallow characters made with multiple code points in character class syntax.

`linter.rules.suspicious.noMisleadingCharacterClass.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noMisleadingCharacterClass.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noMisleadingCharacterClass.options`

Rule’s options

`linter.rules.suspicious.noMisleadingInstantiator`

Enforce proper usage of new and constructor.

`linter.rules.suspicious.noMisleadingInstantiator.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noMisleadingInstantiator.options`

Rule’s options

`linter.rules.suspicious.noMisrefactoredShorthandAssign`

Disallow shorthand assign when variable appears on both sides.

`linter.rules.suspicious.noMisrefactoredShorthandAssign.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noMisrefactoredShorthandAssign.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noMisrefactoredShorthandAssign.options`

Rule’s options

`linter.rules.suspicious.noPrototypeBuiltins`

Disallow direct use of Object.prototype builtins.

`linter.rules.suspicious.noPrototypeBuiltins.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noPrototypeBuiltins.options`

Rule’s options

`linter.rules.suspicious.noRedeclare`

Disallow variable, function, class, and type redeclarations in the same scope.

`linter.rules.suspicious.noRedeclare.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noRedeclare.options`

Rule’s options

`linter.rules.suspicious.noRedundantUseStrict`

Prevents from having redundant “use strict”.

`linter.rules.suspicious.noRedundantUseStrict.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noRedundantUseStrict.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noRedundantUseStrict.options`

Rule’s options

`linter.rules.suspicious.noSelfCompare`

Disallow comparisons where both sides are exactly the same.

`linter.rules.suspicious.noSelfCompare.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noSelfCompare.options`

Rule’s options

`linter.rules.suspicious.noShadowRestrictedNames`

Disallow identifiers from shadowing restricted names.

`linter.rules.suspicious.noShadowRestrictedNames.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noShadowRestrictedNames.options`

Rule’s options

`linter.rules.suspicious.noSkippedTests`

Disallow disabled tests.

`linter.rules.suspicious.noSkippedTests.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noSkippedTests.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noSkippedTests.options`

Rule’s options

`linter.rules.suspicious.noSparseArray`

Disallow sparse arrays

`linter.rules.suspicious.noSparseArray.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noSparseArray.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noSparseArray.options`

Rule’s options

`linter.rules.suspicious.noSuspiciousSemicolonInJsx`

It detects possible “wrong” semicolons inside JSX elements.

`linter.rules.suspicious.noSuspiciousSemicolonInJsx.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noSuspiciousSemicolonInJsx.options`

Rule’s options

`linter.rules.suspicious.noThenProperty`

Disallow then property.

`linter.rules.suspicious.noThenProperty.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noThenProperty.options`

Rule’s options

`linter.rules.suspicious.noUnsafeDeclarationMerging`

Disallow unsafe declaration merging between interfaces and classes.

`linter.rules.suspicious.noUnsafeDeclarationMerging.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noUnsafeDeclarationMerging.options`

Rule’s options

`linter.rules.suspicious.noUnsafeNegation`

Disallow using unsafe negation.

`linter.rules.suspicious.noUnsafeNegation.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.noUnsafeNegation.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.noUnsafeNegation.options`

Rule’s options

`linter.rules.suspicious.recommended`

It enables the recommended rules for this group

`linter.rules.suspicious.useAwait`

Ensure async functions utilize await.

`linter.rules.suspicious.useAwait.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.useAwait.options`

Rule’s options

`linter.rules.suspicious.useDefaultSwitchClauseLast`

Enforce default clauses in switch statements to be last

`linter.rules.suspicious.useDefaultSwitchClauseLast.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.useDefaultSwitchClauseLast.options`

Rule’s options

`linter.rules.suspicious.useGetterReturn`

Enforce get methods to always return a value.

`linter.rules.suspicious.useGetterReturn.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.useGetterReturn.options`

Rule’s options

`linter.rules.suspicious.useIsArray`

Use Array.isArray() instead of instanceof Array.

`linter.rules.suspicious.useIsArray.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.useIsArray.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.useIsArray.options`

Rule’s options

`linter.rules.suspicious.useNamespaceKeyword`

Require using the namespace keyword over the module keyword to declare TypeScript namespaces.

`linter.rules.suspicious.useNamespaceKeyword.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.useNamespaceKeyword.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.useNamespaceKeyword.options`

Rule’s options

`linter.rules.suspicious.useValidTypeof`

This rule verifies the result of typeof $expr unary expressions is being compared to valid values, either string literals containing valid type names or other typeof expressions

`linter.rules.suspicious.useValidTypeof.fix`

The kind of the code actions emitted by the rule

Used to identify the kind of code action emitted by a rule

`linter.rules.suspicious.useValidTypeof.level`

The severity of the emitted diagnostics by the rule

`linter.rules.suspicious.useValidTypeof.options`

Rule’s options

`organizeImports`

The configuration of the import sorting

`organizeImports.enabled`

Enables the organization of imports

`organizeImports.ignore`

A list of Unix shell style patterns. The formatter will ignore files/folders that will match these patterns.

`organizeImports.include`

A list of Unix shell style patterns. The formatter will include files/folders that will match these patterns.

`overrides`

A list of granular patterns that should be applied only to a sub set of files

`vcs`

The configuration of the VCS integration

Set of properties to integrate Biome with a VCS software.

`vcs.clientKind`

The kind of client.

`vcs.defaultBranch`

The main branch of the project

`vcs.enabled`

Whether Biome should integrate itself with the VCS client

`vcs.root`

The folder where Biome should check for VCS files. By default, Biome will use the same folder where biome.json was found.

If Biome can’t find the configuration, it will attempt to use the current working directory. If no current working directory can’t be found, Biome won’t use the VCS integration, and a diagnostic will be emitted

`vcs.useIgnoreFile`

Whether Biome should use the VCS ignore file. When [true], Biome will ignore the files specified in the ignore file.