All versions since 2.4.12

2.4.12

Patch Changes

#9376 9701a33 Thanks @dyc3! - Added the nursery/noIdenticalTestTitle lint rule. This rule disallows using the same title for two describe blocks or two test cases at the same nesting level.

1
describe("foo", () => {});
2
describe("foo", () => {
3
  // invalid: same title as previous describe block
4
  test("baz", () => {});
5
  test("baz", () => {}); // invalid: same title as previous test case
6
});

#9889 7ae83f2 Thanks @dyc3! - Improved the diagnostics for useForOf to better explain the problem, why it matters, and how to fix it.

#9916 27dd7b1 Thanks @Jayllyz! - Added a new nursery rule noComponentHookFactories, that disallows defining React components or custom hooks inside other functions.

For example, the following snippets trigger the rule:

1
function createComponent(label) {
2
  function MyComponent() {
3
    return <div>{label}</div>;
4
  }
5
  return MyComponent;
6
}

1
function Parent() {
2
  function Child() {
3
    return <div />;
4
  }
5
  return <Child />;
6
}

#9980 098f1ff Thanks @ematipico! - Fixed #9941: Biome now emits a warning diagnostic when a file exceed the files.maxSize limit.
#9942 9956f1d Thanks @dyc3! - Fixed #9918: useConsistentTestIt no longer panics when applying fixes to chained calls such as test.for([])("x", () => {});.
#9891 4d9ac51 Thanks @dyc3! - Improved the noGlobalObjectCalls diagnostic to better explain why calling global objects like Math or JSON is invalid and how to fix it.
#9902 3f4d103 Thanks @ematipico! - Fixed #9901: the command lint --write is now idempotent when it’s run against HTML-ish files that contains scripts and styles.
#9891 4d9ac51 Thanks @dyc3! - Improved the noMultiStr diagnostic to explain why escaped multiline strings are discouraged and what to use instead.
#9966 322675e Thanks @siketyan! - Fixed #9113: Biome now parses and formats @media and other conditional blocks correctly inside embedded CSS snippets.
#9835 f8d49d9 Thanks @bmish! - The noFloatingPromises rule now detects floating promises through cross-module generic wrapper functions. Previously, patterns like export const fn = trace(asyncFn) — where trace preserves the function signature via a generic <F>(fn: F): F — were invisible to the rule when the wrapper was defined in a different file.
#9981 02bd8dd Thanks @siketyan! - Fixed #9975: Biome now parses nested CSS selectors correctly inside embedded snippets without requiring an explicit &.
#9949 e0ba71d Thanks @Netail! - Added the nursery rule useIframeSandbox, which enforces the sandbox attribute for iframe tags.

Invalid:
```
1
<iframe></iframe>
```
#9913 d417803 Thanks @Netail! - Added the nursery rule noJsxNamespace, which disallows JSX namespace syntax.

Invalid:
```
1
<ns:testcomponent />
```
#9892 e75d70e Thanks @dyc3! - Improved the noSelfCompare diagnostic to better explain why comparing a value to itself is suspicious and what to use for NaN checks.
#9861 2cff700 Thanks @dyc3! - Added the new nursery rule useVarsOnTop, which requires var declarations to appear at the top of their containing scope.

For example, the following code now triggers the rule:
```
1
function f() {
2
  doSomething();
3
  var value = 1;
4
}
```
#9892 e75d70e Thanks @dyc3! - Improved the noThenProperty diagnostic to better explain why exposing then can create thenable behavior and how to avoid it.
#9892 e75d70e Thanks @dyc3! - Improved the noShorthandPropertyOverrides diagnostic to explain why later shorthand declarations can unintentionally overwrite earlier longhand properties.
#9978 4847715 Thanks @mdevils! - Fixed #9744: useExhaustiveDependencies no longer reports false positives for variables obtained via object destructuring with computed keys, e.g. const { [KEY]: key1 } = props.
#9892 e75d70e Thanks @dyc3! - Improved the noRootType diagnostic to better explain that the reported root type is disallowed by project configuration and how to proceed.
#9927 7974ab7 Thanks @dyc3! - Added eslint-plugin-unicorn’s no-nested-ternary as a rule source for noNestedTernary
#9873 19ff706 Thanks @minseong0324! - noMisleadingReturnType now checks class methods, object methods, and getters in addition to functions.
#9888 362b638 Thanks @dyc3! - Updated metadata for biome migrate eslint to better reflect which ESLint rules are redundant versus unsupported versus unimplemented.
#9892 e75d70e Thanks @dyc3! - Improved the noAutofocus diagnostic to better explain why autofocus harms accessibility outside allowed modal contexts.
#9982 d6bdf4a Thanks @dyc3! - Improved performance of noMagicNumbers. Biome now maps ESLint no-magic-numbers sources more accurately during biome migrate eslint.
#9889 7ae83f2 Thanks @dyc3! - Improved the diagnostics for noConstantCondition to better explain the problem, why it matters, and how to fix it.
#9866 40bd180 Thanks @dyc3! - Added a new nursery rule noExcessiveSelectorClasses, which limits how many class selectors can appear in a single CSS selector.
#9796 f1c1363 Thanks @dyc3! - Added a new nursery rule useStringStartsEndsWith, which prefers startsWith() and endsWith() over verbose string prefix and suffix checks.

The rule uses type information, so it only reports on strings and skips array lookups such as items[0] === "a".
#9942 9956f1d Thanks @dyc3! - Fixed the safe fix for noSkippedTests so it no longer panics when rewriting skipped test function names such as xit(), xtest(), and xdescribe().
#9874 9e570d1 Thanks @minseong0324! - Type-aware lint rules now resolve members through Pick<T, K> and Omit<T, K> utility types.
#9909 0d0e611 Thanks @Netail! - Added the nursery rule useReactAsyncServerFunction, which requires React server actions to be async.

Invalid:
```
1
function serverFunction() {
2
  "use server";
3
  // ...
4
}
```
#9925 29accb3 Thanks @ematipico! - Fixed #9910: added support for parsing member expressions in Svelte directive properties. Biome now correctly parses directives like in:renderer.in|global, use:obj.action, and deeply nested forms like in:a.b.c|global.
#9904 e7775a5 Thanks @ematipico! - Fixed #9626: noUnresolvedImports no longer reports false positives for named imports from packages that have a corresponding @types/* package installed. For example, import { useState } from "react" with @types/react installed is now correctly recognised.
#9942 9956f1d Thanks @dyc3! - Fixed the safe fix for noFocusedTests so it no longer panics when rewriting focused test function names such as fit() and fdescribe().
#9577 c499f46 Thanks @tt-a1i! - Added the nursery rule useReduceTypeParameter. It flags type assertions on the initial value passed to Array#reduce and Array#reduceRight and recommends using a type parameter instead.
```
1
// before: type assertion on initial value
2
arr.reduce((sum, num) => sum + num, [] as number[]);
3

4
// after: type parameter on the call
5
arr.reduce<number[]>((sum, num) => sum + num, []);
```
#9895 1c8e1ef Thanks @Netail! - Added extra rule sources from react-xyz. biome migrate eslint should do a bit better detecting rules in your eslint configurations.
#9891 4d9ac51 Thanks @dyc3! - Improved the noInvalidUseBeforeDeclaration diagnostic to better explain why using a declaration too early is problematic and how to fix it.
#9889 7ae83f2 Thanks @dyc3! - Improved the diagnostics for noRedeclare to better explain the problem, why it matters, and how to fix it.
#9875 a951586 Thanks @minseong0324! - Type-aware lint rules now resolve members through Partial<T>, Required<T>, and Readonly<T> utility types, preserving optional, readonly, and nullable member flags.

2.4.13

Patch Changes

#9969 c5eb92b Thanks @officialasishkumar! - Added the nursery rule noUnnecessaryTemplateExpression, which disallows template literals that only contain string literal expressions. These can be replaced with a simpler string literal.

For example, the following code triggers the rule:
```
1
const a = `${"hello"}`; // can be 'hello'
2
const b = `${"prefix"}_suffix`; // can be 'prefix_suffix'
3
const c = `${"a"}${"b"}`; // can be 'ab'
```

#10037 f785e8c Thanks @minseong0324! - Fixed #9810: noMisleadingReturnType no longer reports false positives on a getter with a matching setter in the same namespace.

1
class Store {
2
  get status(): string {
3
    if (Math.random() > 0.5) return "loading";
4
    return "idle";
5
  }
6
  set status(v: string) {}
7
}

#10084 5e2f90c Thanks @jiwon79! - Fixed #10034: noUselessEscapeInRegex no longer flags escapes of ClassSetReservedPunctuator characters (&, !, #, %, ,, :, ;, <, =, >, @, `, ~) inside v-flag character classes as useless. These characters are reserved as individual code points in v-mode, so the escape is required.

The following pattern is now considered valid:
```
1
/[a-z\&]/v;
```
#10063 c9ffa16 Thanks @Netail! - Added extra rule sources from ESLint CSS. biome migrate eslint should do a bit better detecting rules in your eslint configurations.
#10035 946b50e Thanks @Netail! - Fixed #10032: useIframeSandbox now flags if there’s no initializer value.
#9865 68fb8d4 Thanks @dyc3! - Added the new nursery rule useDomNodeTextContent, which prefers textContent over innerText for DOM node text access and destructuring.

For example, the following snippet triggers the rule:
```
1
const foo = node.innerText;
```
#10023 bd1e74f Thanks @ematipico! - Added a new nursery rule noReactNativeDeepImports that disallows deep imports from the react-native package. Internal paths like react-native/Libraries/... are not part of the public API and may change between versions.

For example, the following code triggers the rule:
```
1
import View from "react-native/Libraries/Components/View/View";
```
#9885 3dce737 Thanks @dyc3! - Added a new nursery rule useDomQuerySelector that prefers querySelector() and querySelectorAll() over older DOM query methods such as getElementById() and getElementsByClassName().
#9995 4da9caf Thanks @siketyan! - Fixed #9994: Biome now parses nested CSS rules correctly when declarations follow them inside embedded snippets.
#10009 b41cc5a Thanks @Jayllyz! - Fixed #10004: noComponentHookFactories no longer reports false positives for object methods and class methods.
#9988 eabf54a Thanks @Netail! - Tweaked the diagnostics range for useAltText, useButtonType, useHtmlLang, useIframeTitle, useValidAriaRole & useIfameSandbox to report on the opening tag instead of the full tag.
#10043 fc65902 Thanks @mujpao! - Fixed #10003: Biome no longer panics when parsing Svelte files containing {#}.
#9815 5cc83b1 Thanks @dyc3! - Added the new nursery rule noLoopFunc. When enabled, it warns when a function declared inside a loop captures outer variables that can change across iterations.
#9702 ef470ba Thanks @ryan-m-walker! - Added the nursery rule useRegexpTest that enforces RegExp.prototype.test() over String.prototype.match() and RegExp.prototype.exec() in boolean contexts. test() returns a boolean directly, avoiding unnecessary computation of match results.

Invalid
```
1
if ("hello world".match(/hello/)) {
2
}
```
Valid
```
1
if (/hello/.test("hello world")) {
2
}
```
#9743 245307d Thanks @leetdavid! - Fixed #2245: Svelte <script> tag language detection when the generics attribute contains > characters (e.g., <script lang="ts" generics="T extends Record<string, unknown>">). Biome now correctly recognizes TypeScript in such script blocks.

#10046 0707de7 Thanks @Conaclos! - Fixed #10038: organizeImports now sorts imports in TypeScript modules and declaration files.

1
declare module "mymodule" {
2
   import type { B } from "b";
3
  import type { A } from "a";
4
   import type { B } from "b";
5
}

#10012 94ccca9 Thanks @ematipico! - Added the nursery rule noReactNativeLiteralColors, which disallows color literals inside React Native styles.

The rule belongs to the reactNative domain. It reports properties whose name contains color and whose value is a string literal when they appear inside a StyleSheet.create(...) call or inside a JSX attribute whose name contains style.
```
1
// Invalid
2
const Hello = () => <Text style={{ backgroundColor: "#FFFFFF" }}>hi</Text>;
3

4
const styles = StyleSheet.create({
5
  text: { color: "red" },
6
});
```
```
1
// Valid
2
const red = "#f00";
3
const styles = StyleSheet.create({
4
  text: { color: red },
5
});
```
#10005 131019e Thanks @ematipico! - Added the nursery rule noReactNativeRawText, which disallows raw text outside of <Text> components in React Native.

The rule belongs to the new reactNative domain.
```
1
// Invalid
2
<View>some text</View>
3
<View>{'some text'}</View>
```
```
1
// Valid
2
<View>
3
  <Text>some text</Text>
4
</View>
```
Additional components can be allowlisted through the skip option:
```
1
{
2
  "options": {
3
    "skip": ["Title"]
4
  }
5
}
```
#9911 1603f78 Thanks @Netail! - Added the nursery rule noJsxLeakedDollar, which flags text nodes with a trailing $ if the next sibling node is a JSX expression. This could be an unintentional mistake, resulting in a ’$’ being rendered as text in the output.

Invalid:
```
1
function MyComponent({ user }) {
2
  return <div>Hello ${user.name}</div>;
3
}
```
#9999 f42405f Thanks @minseong0324! - Fixed noMisleadingReturnType incorrectly flagging functions with reassigned let variables.
#10075 295f97f Thanks @ematipico! - Fixed #9983: Biome now parses functions declared inside Svelte #snippet blocks without throwing errors.
#10006 cf4c1c9 Thanks @minseong0324! - Fixed #9810: noMisleadingReturnType incorrectly flagging nested object literals with widened properties.
#10033 11ddc05 Thanks @ematipico! - Added the nursery rule useReactNativePlatformComponents that ensures platform-specific React Native components (e.g. ProgressBarAndroid, ActivityIndicatorIOS) are only imported in files with a matching platform suffix. It also reports when Android and iOS components are mixed in the same file.

The following code triggers the rule when the file does not have an .android.js suffix:
file.js
```
1
import { ProgressBarAndroid } from "react-native";
```

2.4.14

Patch Changes

#9393 491b171 Thanks @dyc3! - Added the nursery rule useTestHooksOnTop in the test domain. The rule flags lifecycle hooks (beforeEach, beforeAll, afterEach, afterAll) that appear after test cases in the same block, enforcing that hooks are defined before any test case.
#10157 eefc5ab Thanks @dyc3! - Fixed #7882: The HTML parser will now emit better diagnostics when it encounters a void element with a closing tag, such as <br></br>. Previously, the parser would emit multiple diagnostics with conflicting advice. Now it emits a single diagnostic that clearly states that void elements should not have closing tags.
#10054 0e9f569 Thanks @minseong0324! - noMisleadingReturnType no longer misses widening from concrete object types, class instances, object literals, tuples, functions, and regular expressions to : object.

A function annotated : object returning an object literal:
```
1
function f(): object {
2
  return { retry: true };
3
}
```
#10116 53269eb Thanks @jiwon79! - Fixed #6201: noUselessEscapeInRegex no longer flags an escaped backslash followed by - as a useless escape. Patterns like /[\\-]/ are now considered valid because the second \ is the escaped backslash, not an unnecessary escape of the trailing dash.
#10092 33d8543 Thanks @Conaclos! - Fixed #9097: organizeImports no longer adds a blank line between a never-matched group and a matched group.

Given the following organizeImports options:
```
1
{
2
  "groups": [":NODE:", ":BLANK_LINE:", ":PACKAGE:", ":BLANK_LINE:", ":PATH:"]
3
}
```
The following code…
```
1
// Comment
2
import "package";
3
import "./file.js";
```
…was organized as:
```
1

2
// Comment
3
import "package";
4

5
import "./file.js";
```
A blank line was added even though the group ‘:NODE:’ doesn’t match any imports here. :BLANK_LINE: between never-matched groups and matched groups are now ignored. The code is now organized as:
```
1
// Comment
2
import "package";
3

4
import "./file.js";
```
#10138 a10b6c1 Thanks @dyc3! - Fixed Vue v-for handling for noUndeclaredVariables and noUnusedVariables. Biome now recognizes variables declared by v-for directives and references to iterated values in Vue templates.
#10115 d428d76 Thanks @minseong0324! - noMisleadingReturnType no longer reports false positives when a union return type’s boolean variant is covered by both true and false returns.
#9922 7acf1e0 Thanks @dyc3! - Added the new nursery rule noReactStringRefs, which disallows legacy React string refs such as ref="hello" and this.refs.hello.

Biome also reports template-literal refs such as ref={`hello`}, so React code can consistently migrate to callback refs, createRef(), or useRef().
#10010 f3e76ab Thanks @dyc3! - Fixed a bug in the LSP file watcher registration so Biome now watches .biome.json and .biome.jsonc configuration files and reloads workspace settings when they change.
#10176 8a40ef8 Thanks @dyc3! - Fixed #10011: The noThisInStatic rule no longer reports this when it is used as the constructor target in new this(...), which is required for inherited static factory methods.
#10163 6867e96 Thanks @jiwon79! - Fixed #9884: The useSortedAttributes auto-fix no longer corrupts source code when both an outer JSX element and a nested JSX-valued attribute have unsorted attributes in the same pass. Multiple unsorted groups separated by spread or shorthand attributes within the same JSX element are now reported as a single diagnostic.
#10079 d29dd19 Thanks @Damix48! - Fixed false positive in noAssignInExpressions for Svelte {@const} blocks. Assignments in {@const name = value} are now correctly recognized as declarations rather than accidental assignments in expressions.
#10080 5d8fdac Thanks @Damix48! - Fixed parsing of closing parentheses in Svelte {#each} block key expressions. Biome now correctly parses method calls and other parenthesised expressions used as keys.

For example, the following snippets are now parsed correctly:
```
1
{#each numbers as number, index (number.toString())}
2
  <p>{number}</p>
3
{/each}
4

5
{#each numbers as number (key(number))}
6
  <p>{number}</p>
7
{/each}
```
#10140 e7024b9 Thanks @solithcy! - Fixed #10135: Biome no longer crashes on missing Svelte template expressions.

The following code snippet longer panics:
```
1
{#if }
2
 <p>^ this would previously crash</p>
3
{/if}
4
{@const }
5
<p>    ^ this would also crash</p>
```
#10111 7818009 Thanks @jiwon79! - Fixed #9997: noDuplicateSelectors no longer reports false positives for selectors inside @scope queries. Biome now treats @scope as a separate at-rule context, like @media, @supports, @container, and @starting-style.

The following snippet is no longer flagged as a duplicate:
```
1
.Example {
2
  padding: 0;
3
}
4

5
@scope (.theme-dark) {
6
  .Example {
7
    color: white;
8
  }
9
}
```
#9926 d62b331 Thanks @dyc3! - Added the nursery lint rule useMathMinMax, which prefers Math.min() and Math.max() over equivalent ternary comparisons.

For example, this code:
```
1
const min = a < b ? a : b;
```
is much more readable when rewritten as:
```
1
const min = Math.min(a, b);
```
#10115 d428d76 Thanks @minseong0324! - useExhaustiveSwitchCases now flags missing true/false cases for boolean discriminants, including when boolean is a union variant.
#10125 a55a0b6 Thanks @bmish! - Fixed a resolver bug where packages that define a typed entry point through package.json’s main field but omit types were ignored during type-aware resolution. Type-aware rules such as noFloatingPromises can now inspect imports from those packages.
#10117 895e809 Thanks @denizdogan! - Added support for the corner-shape family of CSS properties and the superellipse()/squircle() value functions, so noUnknownProperty and noUnknownFunction no longer flag them as unknown.

New known properties: corner-shape, corner-block-end-shape, corner-block-start-shape, corner-bottom-left-shape, corner-bottom-right-shape, corner-bottom-shape, corner-end-end-shape, corner-end-start-shape, corner-inline-end-shape, corner-inline-start-shape, corner-left-shape, corner-right-shape, corner-start-end-shape, corner-start-start-shape, corner-top-left-shape, corner-top-right-shape, corner-top-shape.

New known value functions: superellipse(), squircle().
#8620 8df8f73 Thanks @dyc3! - Fixed #8062: Added support for parsing Vue v-for directives more accurately.
#10191 aa055cd Thanks @guney! - Now the rule noStaticElementInteractions doesn’t trigger custom elements.
#9757 2c62594 Thanks @dyc3! - Fixed #9099: the HTML formatter collapsing non-text children (inline elements, Svelte expressions, comments) onto a single line when the source had them on separate lines. Biome now preserves the user’s intended line breaks for exclusively non-text children.

For example, the following Svelte snippet is now preserved instead of being collapsed to <div>{name}</div>:
```
1
<div>
2
  {name}
3
</div>
```
Similarly, HTML elements like <span> inside a <div> are now preserved when written on their own line:
```
1
<div>
2
  <span>text</span>
3
</div>
```
#10105 e7c1a6d Thanks @jiwon79! - Fixed #10039: useReadonlyClassProperties now detects unreassigned private members in class expressions and export default classes, not only in class declarations.

The following patterns are now correctly flagged:
```
1
const AnonClass = class {
2
  #prop = 123;
3
  constructor() {
4
    console.log(this.#prop);
5
  }
6
};
7

8
export default class {
9
  #prop = 123;
10
  constructor() {
11
    console.log(this.#prop);
12
  }
13
}
```
#10141 46a77d0 Thanks @minseong0324! - Improved noUnnecessaryConditions to detect conditions that are always truthy because they check built-in global class instances such as Date, Map, Set, WeakMap, and Error.
#10178 7b05a89 Thanks @dyc3! - Fixed #10177: The HTML parser no longer reports lowercase html or doctype text as invalid after void elements such as <br>.
#10155 0d4595d Thanks @jiwon79! - Fixed #10045: the CSS formatter no longer compounds indentation inside nested functional pseudo-classes such as :not(:where(...)), :is(:where(...)), and similar combinations. The same fix also removes one level of unnecessary indentation that was added inside any pseudo-class function whose argument list wrapped onto multiple lines, including :nth-child(... of ...), ::part(...), and :active-view-transition-type(...). The following snippet is now correctly formatted, matching Prettier.
```
1
input:not(
2
  :where(
3
    [type="submit"],
4
    [type="checkbox"],
5
    [type="radio"],
6
    [type="button"],
7
    [type="reset"]
8
  )
9
) {
10
  inline-size: 100%;
11
}
```
#10112 6f0251e Thanks @dyc3! - Fixed #10110: Biome’s parser now accepts surrogate code points in JavaScript string \u{...} escapes.
#10141 46a77d0 Thanks @minseong0324! - Improved noMisleadingReturnType to detect object return annotations that hide built-in global class instances such as Date, Map, Set, WeakMap, and Error.
#10083 4a664c1 Thanks @ematipico! - Added two new options to noShadow, both defaulting to true to match typescript-eslint’s behavior.

Fixed #9482: Added ignoreFunctionTypeParameterNameValueShadow option. When enabled, parameter names inside function type annotations (e.g. (options: unknown) => void) are not flagged as shadowing outer variables.

Fixed #7812: Added ignoreTypeValueShadow option. When enabled, a value binding that shares its name with a type-only declaration (type alias or interface) is not flagged, since types and values occupy separate namespaces in TypeScript.
#9286 52695cf Thanks @Hugo-Polloli! - Fixed #6316: Biome now resolves Svelte $store references to the underlying store binding in semantic analysis, preventing false noUndeclaredVariables diagnostics when the store is declared.
#10188 ae659dd Thanks @dyc3! - Added a new nursery rule noExcessiveNestedCallbacks, which disallows callbacks nested deeper than the configured maximum.
#9757 2c62594 Thanks @dyc3! - Fixed #9450: the HTML formatter now correctly preserves multiline formatting for nested <template> elements (e.g. <template #body>) when the source has children on separate lines. Previously, the children were collapsed onto a single line.
```
1
<template>
2
  <UModal>
3
    <template #body> <p>content</p> </template>
4
    <template #body>
5
      <p>content</p>
6
    </template>
7
  </UModal>
8
</template>
```
#10118 c6edcb4 Thanks @Netail! - Fixed #10024: biome migrate eslint correctly migrates eslint rules that belong to multiple Biome rules.

2.4.15

Patch Changes

#9394 ba3480e Thanks @dyc3! - Added the nursery rule useTestHooksInOrder in the test domain. The rule enforces that Jest/Vitest lifecycle hooks (beforeAll, beforeEach, afterEach, afterAll) are declared in the order they execute, making test setup and teardown easier to reason about.
#10254 e0a54cc Thanks @dyc3! - Added a new nursery rule useVueNextTickPromise, which enforces Promise syntax when using Vue nextTick.

For example, the following snippet triggers the rule:
```
1
import { nextTick } from "vue";
2

3
nextTick(() => {
4
  updateDom();
5
});
```
#10219 64aee45 Thanks @dyc3! - Added a new nursery rule noVueVOnNumberValues, that disallows deprecated number modifiers on Vue v-on directives.

For example, the following snippet triggers the rule:
```
1
<input @keyup.13="submit" />
```
#10195 7b8d4e1 Thanks @dyc3! - Added the new nursery rule useVueValidVFor, which validates Vue v-for directives and reports invalid aliases, missing component keys, and keys that do not use iteration variables.
#10238 1110256 Thanks @dyc3! - Added the recommended nursery rule noVueImportCompilerMacros, which disallows importing Vue compiler macros such as defineProps from vue because they are automatically available.
#10201 1a08f89 Thanks @realknove! - Fixed #10193: style/useReadonlyClassProperties no longer reports class properties as readonly-able when they are assigned inside arrow callbacks nested in class property initializers.
#9574 3bd2b6a Thanks @Conaclos! - Fixed #9530. The diagnostics of organizeImports are now more detailed and more precise. They are also better at localizing where the issue is.
#10205 a704a6c Thanks @Conaclos! - Fixed #10185. `organizeImports now errors when it encounters an unknown predefined group.

The following configuration is now reported as invalid because :INEXISTENT: is an unknown predefined group.
```
1
{
2
  "assist": {
3
    "actions": {
4
      "source": {
5
        "organizeImports": { "options": { "groups": [":INEXISTENT:"] } }
6
      }
7
    }
8
  }
9
}
```
#10052 b565bed Thanks @minseong0324! - Improved noMisleadingReturnType: it now flags union annotations whose extra variants are never returned, and suggests the narrower type (e.g. string | null → string).

These functions are now reported because null and number are included in the return annotations but never returned:
```
1
function getUser(): string | null {
2
  return "hello";
3
} // null is never returned
4
function getCode(): string | number {
5
  return "hello";
6
} // number is never returned
```
#10213 ac30057 Thanks @dyc3! - Fixed #9450: HTML and Vue element formatting now preserves child line breaks when an element contains another element child on its own line, instead of collapsing the child element onto the same line.
#10275 9ee6c03 Thanks @solithcy! - Fixed #10274: Svelte templates with missing expressions no longer parsed as HtmlBogusElement
#10143 56798a7 Thanks @minseong0324! - noMisleadingReturnType now detects misleading return type annotations when object literal properties are initialized with as const.

This function is now reported because the return annotation widens a property initialized with as const:
```
1
function f(): { value: string } {
2
  return { value: "text" as const };
3
}
```
#10143 56798a7 Thanks @minseong0324! - noUselessTypeConversion now detects redundant conversions on object literal properties initialized with as const.

This conversion is now reported because message.value is inferred as a string literal:
```
1
const message = { value: "text" as const };
2
String(message.value);
```
#9807 0ae5840 Thanks @dyc3! - Added the new nursery rule useThisInClassMethods, based on ESLint’s class-methods-use-this.

The rule now reports instance methods, getters, setters, and function-valued instance fields that do not use this, and biome migrate eslint preserves the supported ignoreMethods, ignoreOverrideMethods, and ignoreClassesWithImplements options.

Invalid:
```
1
class Foo {
2
  bar() {
3
    // does not use `this`, invalid
4
    console.log("Hello Biome");
5
  }
6
}
```
#10258 e7b18f7 Thanks @ematipico! - Improved linter performance by narrowing the query nodes for several lint rules, reducing how often they are evaluated.
#10273 04e22a1 Thanks @dyc3! - Fixed #10271: The HTML parser now correctly parses of as text content when in text contexts.
#9838 83f7385 Thanks @dyc3! - Added the nursery rule noBaseToString, which reports stringification sites that fall back to Object’s default "[object Object]" formatting. The rule also supports the ignoredTypeNames option.
#10143 56798a7 Thanks @minseong0324! - useExhaustiveSwitchCases now checks switch statements over object literal properties initialized with as const.

This switch is now reported because status.kind is inferred as the string literal "ready" but no case handles it:
```
1
const status = { kind: "ready" as const };
2
switch (status.kind) {
3
}
```
#10143 56798a7 Thanks @minseong0324! - useStringStartsEndsWith now detects string index comparisons on object literal properties initialized with as const.

This comparison is now reported because message.value is inferred as a string literal:
```
1
const message = { value: "hello" as const };
2
message.value[0] === "h";
```

2.4.16

Patch Changes

#10329 ef764d5 Thanks @Conaclos! - Fixed an issue where diagnostics showed an incorrect location in Astro files.

#10363 50aa415 Thanks @dyc3! - Fixed HTML formatting for a case where comments could cause the formatter to split up a closing tag, which would cause the resulting HTML to be syntactically invalid.

Input:

1
<span
2
  ><!-- 1
3
--><span>a</span
4
  ><!-- 2
5
--><span>b</span
6
  ><!-- 3
7
--></span>

Output:

1
<span
2
  ><!-- 1
3
--> <span>a</span<!-- 2
4
--> ><span>b</span><!-- 3
5
--><span>a</span><!-- 2
6
--><span>b</span><!-- 3
7
--></span
8
>

#10465 0c718da Thanks @dfedoryshchev! - Fixed diagnostics emitted by the noUntrustedLicenses rule.
#10358 05c2617 Thanks @dyc3! - Fixed #10356: biome rage --linter now displays rules enabled through linter domains in the enabled rules list.
#10300 950247c Thanks @dyc3! - Fixed #10265: Svelte function bindings such as bind:value={get, set} are now parsed more precisely, so noCommaOperator won’t emit false positives for that syntax anymore.
#9786 e71f584 Thanks @MeGaNeKoS! - Fixed #8480: useDestructuring now provides variableDeclarator and assignmentExpression options to control which contexts enforce destructuring, matching ESLint’s prefer-destructuring configuration. Both default to {array: true, object: true}. The diagnostic for object destructuring in assignment expressions now instructs users to wrap the assignment in parentheses.
#10425 1948b72 Thanks @sjh9714! - Fixed #10244: The useOptionalChain rule now detects negated guard inequality chains like !foo || foo.bar !== "x".
#10442 001f94f Thanks @ematipico! - Fixed #10411: noMisusedPromises no longer causes a stack overflow when a nested function returns an object with shorthand properties that shadow destructured variables from an outer scope.
#10318 9b1577f Thanks @dyc3! - Added support for formatter.trailingCommas in overrides. This option was previously available in the top-level formatter configuration but missing from formatter overrides.
#10319 2e37709 Thanks @dyc3! - Fixed Vue and Svelte formatting for standalone interpolations in inline elements. Biome now preserves existing newlines in cases like:
```
1
<span> {{ value }} </span>
2
<span>
3
  {{ value }}
4
</span>
```
#10365 0a58eb0 Thanks @Netail! - Fixed #10361: noUnusedFunctionParameters now mentions the parameter name in the diagnostic.
#10439 df6b867 Thanks @denbezrukov! - Fixed CSS and SCSS formatting for comments around declaration colons so comments between property names, colons, and values stay at the same boundary as Prettier.
```
1
.selector {
2
  color: /* red, */
3
    blue;
4
  color: /* red, */ blue;
5
}
```
#10344 b30208c Thanks @siketyan! - Fixed #10123: Corrected the noReactNativeDeepImports source rule to point to the proper upstream rule, so users can migrate from the original rule correctly.
#10328 b59133f Thanks @dyc3! - Fixed #10309: Biome no longer adds newlines to Astro frontmatter when linter or assist --write mode is enabled.

2.5.0 Latest

Minor Changes

#9539 f0615fd Thanks @ematipico! - Added a new reporter called concise. When --reporter=concise is passed the commands format, lint, check and ci, the diagnostics are printed in a compact manner:

1
! index.ts:2:10: lint/correctness/noUnusedImports: Several of these imports are unused.
2
! main.ts:9:7: lint/correctness/noUnusedVariables: This variable f is unused.
3
× index.ts:8:5: lint/suspicious/noImplicitAnyLet: This variable implicitly has the any type.
4
× main.ts:2:10: lint/suspicious/noRedeclare: Shouldn't redeclare 'z'. Consider to delete it or rename it.

#9495 2056b23 Thanks @aviraldua93! - Added the useKeyWithClickEvents a11y lint rule for HTML files (.html, .vue, .svelte, .astro). This is a port of the existing JSX rule. The rule enforces that elements with an onclick handler also have at least one keyboard event handler (onkeydown, onkeyup, or onkeypress) to ensure keyboard accessibility.

Inherently keyboard-accessible elements (<a>, <button>, <input>, <select>, <textarea>, <option>) are excluded, as are elements hidden from assistive technologies (aria-hidden) or with role="presentation" / role="none".
```
1

2
<div onclick="handleClick()">Click me</div>
3

4

5
<div onclick="handleClick()" onkeydown="handleKeyDown()">Click me</div>
6

7

8
<button onclick="handleClick()">Submit</button>
```
#9152 9ec8500 Thanks @ematipico! - Added new nursery lint rule noUndeclaredClasses for HTML, JSX, and SFC files (Vue, Astro, Svelte). The rule detects CSS class names used in class="..." (or className) attributes that are not defined in any <style> block or linked stylesheet reachable from the file.
```
1

2
<html>
3
  <head>
4
    <style>
5
      .button {
6
        color: blue;
7
      }
8
    </style>
9
  </head>
10
  <body>
11
    <div class="button typo"></div>
12
  </body>
13
</html>
```
#9152 9ec8500 Thanks @ematipico! - Added new nursery lint rule noUnusedClasses for CSS. The rule detects CSS class selectors that are never referenced in any HTML or JSX file that imports the stylesheet. This is a project-domain rule that requires the module graph.
```
1
/* styles.css — .ghost is never used in any importing file */
2
.button {
3
  color: blue;
4
}
5
.ghost {
6
  color: red;
7
}
```
App.jsx
```
1
import "./styles.css";
2
export default () => <div className="button" />;
```
#9546 6567efa Thanks @nhedger! - Added a biome upgrade command for standalone installations. It upgrades Homebrew installs with brew upgrade biome, updates manually installed binaries from the latest GitHub release, and tells npm users to upgrade with their package manager instead.

#9716 701767a Thanks @faizkhairi! - Added the HTML version of the useHeadingContent rule. The rule now enforces that heading elements (h1-h6) have content accessible to screen readers in HTML, Vue, Svelte, and Astro files.

1
<!-- Invalid: empty heading -->
2
<h1></h1>
3

4
<!-- Invalid: heading hidden from screen readers -->
5
<h1 aria-hidden="true">invisible content</h1>
6

7
<!-- Valid: heading with text content -->
8
<h1>heading</h1>
9

10
<!-- Valid: heading with accessible name -->
11
<h1 aria-label="Screen reader content"></h1>

#9582 f437ef8 Thanks @rahuld109! - Added the HTML version of the useKeyWithMouseEvents rule. The rule now enforces that onmouseover is accompanied by onfocus and onmouseout is accompanied by onblur in HTML, Vue, Svelte, and Astro files.
```
1

2
<div onmouseover="handleMouseOver()"></div>
3

4

5
<div onmouseover="handleMouseOver()" onfocus="handleFocus()"></div>
```
#9275 1fdbcee Thanks @ff1451! - Added the new assist action useSortedTypeFields, which sorts the fields of GraphQL object types, interface types and input object types alphabetically, e.g. name, age, id becomes age, id, name.
#10561 78075b7 Thanks @Conaclos! - Added a new style option to useExportType, which enforces a style for exporting types. This is the same option as the one provided by useImportType.
#8987 d16e32b Thanks @DerTimonius! - Ported the useValidAnchor rule to HTML. This rule enforces that all anchors are valid and that they are navigable elements.
#9533 4d251d4 Thanks @ematipico! - The init command now prints the Biome logo.
#10069 0eb9310 Thanks @Netail! - Added the HTML lint rule noStaticElementInteractions, which enforces that static, visible elements (such as <div>) that have click handlers use the valid role attribute.

Invalid:
```
1
<div onclick="myFunction()"></div>
```
#9134 2a43488 Thanks @ematipico! - Added the assist action useSortedPackageJson.

This action organizes package.json fields according to the same conventions as the popular sort-package-json tool.
#9309 7daa18b Thanks @Bertie690! - The allowDoubleNegation option has been added to noImplicitCoercions to allow ignoring double negations inside code.

With the option enabled, the following example is considered valid and is ignored by the rule:
```
1
const truthy = !!value;
```
#9700 894f3fb Thanks @ematipico! - The Biome Language server now supports the “go-to definition” feature.

When the cursor of the mouse is hovering an entity (variable, CSS class, type, etc.), and the command CTRL + click is triggered, the editor jumps to where this entity is defined, if the language server can find it.

Here’s what Biome is able to resolve:
- Variables and types used in JavaScript modules, defined in the same file or imported from another module.
- JSX Components used in JavaScript modules, defined in the same file or imported from another module.
- CSS classes used in JSX and HTML-ish files (Vue, Svelte and Astro), and defined in CSS files.
- Components used in HTML-ish files and defined in other HTML-ish.
- Variables used in HTML-ish files and defined in the same file or imported from another module (JavaScript or HTML-ish).

#10070 bae0710 Thanks @Conaclos! - Added the :STYLE: group matcher for organizeImports that matches style imports.

For example, the following configuration…

1
{
2
  "assist": {
3
    "actions": {
4
      "source": {
5
        "organizeImports": {
6
          "level": "on",
7
          "options": {
8
            "groups": ["**", "!:STYLE:"],
9
            "sortBareImports": true
10
          }
11
        }
12
      }
13
    }
14
  }
15
}

…places style imports last:

1
import "./style.css"
2
import A from "./a.js"
3
import "./style.css"

#9170 e3107de Thanks @mdrobny! - Added bundleDependencies option to NoUndeclaredDependencies rule.

This rule now supports imports of packages that are defined only in bundleDependencies and bundledDependencies arrays.
#9547 01f8473 Thanks @mujpao! - Added new assist rule useSortedAttributes for HTML, porting the existing JSX rule. This rule enforces sorted HTML attributes.

Invalid
```
1
<input type="text" id="name" name="name" />
```
#9366 2ca1117 Thanks @dyc3! - Added the html.parser.vue configuration option. When enabled, it adds support for the parsing of Vue in .html files. Most Vue users don’t need to enable this option since Vue files typically use the .vue extension, but it can be useful for projects that embed Vue syntax in regular HTML files.
#9073 74b20ee Thanks @chocky335! - Added support for applying GritQL plugin rewrites as code actions. GritQL plugins that use the rewrite operator (=>) now produce fixable diagnostics for JavaScript, CSS, and JSON files. By default, plugin rewrites are treated as unsafe fixes and require --write --unsafe to apply. Plugin authors can pass fix_kind = "safe" to register_diagnostic() to mark a fix as safe, allowing it to be applied with just --write.

Example plugin (useConsoleInfo.grit):
```
1
language js
2

3
`console.log($msg)` as $call where {
4
    register_diagnostic(span = $call, message = "Use console.info instead of console.log.", severity = "warn", fix_kind = "safe"),
5
    $call => `console.info($msg)`
6
}
```
Running biome check --write applies safe rewrites. Unsafe rewrites (the default, or fix_kind = "unsafe") still require --write --unsafe.

#9384 f4c9edc Thanks @Conaclos! - Added the sortBareImports option to organizeImports, which allows bare imports to be sorted within other imports when set to false.

1
{
2
  "assist": {
3
    "actions": {
4
      "source": {
5
        "organizeImports": {
6
          "level": "on",
7
          "options": { "sortBareImports": true }
8
        }
9
      }
10
    }
11
  }
12
}

1
import "b";
2
import "a";
3
import "b";
4
import { A } from "a";
5
import "./file";
6
import { Local } from "./file";
7
import "./file";

#8731 e7872bf Thanks @siketyan! - Added the watch mode (--watch) to the CLI for check/format/lint commands. By enabling this option, Biome will re-run the check automatically when any file in the workspace has changed after the first run.
#10106 9b35f78 Thanks @ematipico! - Biome can now format and lint .svg files.
#9967 e9b6c17 Thanks @dyc3! - Added HTML support for noExcessiveLinesPerFile. Biome now reports HTML files that exceed the configured line limit, including when skipBlankLines is enabled.
#9491 b3eb63c Thanks @IxxyDev! - Added the HTML lint rule noAriaUnsupportedElements. This rule enforces that elements that do not support ARIA roles, states, and properties (meta, html, script, style) do not have role or aria-* attributes.
```
1

2
<meta charset="UTF-8" role="meta" />
```
#9306 afd57a6 Thanks @viraxslot! - Added the noNoninteractiveTabindex lint rule for HTML. This rule enforces that tabindex is not used on non-interactive elements, as it can cause usability issues for keyboard users.
```
1
<div tabindex="0">Invalid: non-interactive element</div>
2
`
```
#9276 6d041d9 Thanks @IxxyDev! - Added the HTML lint rule noRedundantRoles. This rule enforces that explicit role attributes are not the same as the implicit/default role of an HTML element. It supports HTML, Vue, Svelte, and Astro files.
```
1

2
<button role="button"></button>
```
#9813 69aadc2 Thanks @ematipico! - Added a new linter configuration called preset. With the new option, users can enable different kinds of rules at once.

The following presets are available:
- "recommended": it enables all Biome-recommended rules, or recommended rules of a group;
- "all": it enables all Biome rules, or enables all rules of a group;
- "none": it disables all Biome rules, or disable all rules of a group.
You can enable recommended rules:
```
1
{
2
  "linter": {
3
    "rules": {
4
      "preset": "recommended"
5
    }
6
  }
7
}
```
You can enable all rules at once:
```
1
{
2
  linter: {
3
    rules: {
4
      preset: "all", // enables all rules
5
    },
6
  },
7
}
```
Or enable all rules for a group:
```
1
{
2
  linter: {
3
    rules: {
4
      style: {
5
        preset: "all", // enables all rules in the style group
6
      },
7
    },
8
  },
9
}
```
This new option, however, doesn’t affect how nursery rules work. Nursery rules must be enabled singularly, due to their nature.

This new option is meant to replace recommended, so make sure to run the migrate command.
#10022 3422d71 Thanks @Netail! - Added the HTML lint rule noNoninteractiveElementToInteractiveRole, which enforces that interactive ARIA roles are not assigned to non-interactive HTML elements.

Invalid:
```
1
<h1 role="checkbox"></h1>
```
#8396 13785fc Thanks @apple-yagi! - Biome now supports pnpm catalogs (default and named) when resolving dependencies for linting. This behavior is opt-in and requires setting javascript.resolver.experimentalPnpmCatalogs to true.
#10028 1009414 Thanks @Netail! - Added the HTML lint rule noInteractiveElementToNoninteractiveRole, which enforces that non-interactive ARIA roles are not assigned to interactive HTML elements.

Invalid:
```
1
<input role="img" />
```
#9853 816302f Thanks @Netail! - Added the new assist action useSortedSelectionSet, which sorts GraphQL selection sets alphabetically, e.g. name, age, id becomes age, id, name.

Invalid:
```
1
query {
2
  name
3
  age
4
  id
5
}
```

#10074 9c7c6eb Thanks @georgephillips! - Added a kind field to the ImportMatcher used by the organizeImports assist action. The new field selects imports by their syntactic kind and currently supports bare (matching side-effect imports such as import "polyfill") with optional ! negation (!bare). The matcher composes with the existing type and source fields, so users can express patterns such as “only bare imports that import a CSS file” ({ "kind": "bare", "source": "**/*.css" }).

For example, with the following configuration:

1
{
2
  "assist": {
3
    "actions": {
4
      "source": {
5
        "organizeImports": {
6
          "level": "on",
7
          "options": {
8
            "sortBareImports": true,
9
            "groups": [
10
              { "kind": "!bare" },
11
              ":BLANK_LINE:",
12
              { "kind": "bare" }
13
            ]
14
          }
15
        }
16
      }
17
    }
18
  }
19
}

…the following code:

1
import "./register-my-component";
2
import { render } from "react-dom";
3
import "./polyfill";
4
import { Button } from "@/components/Button";

…is organized as:

1
import { render } from "react-dom";
2
import { Button } from "@/components/Button";
3

4
import "./polyfill";
5
import "./register-my-component";

#9171 ce65710 Thanks @chocky335! - Added includes option for plugin file scoping. Plugins can now be configured with glob patterns to restrict which files they run on. Use negated globs for exclusions.
```
1
{
2
  "plugins": [
3
    "global-plugin.grit",
4
    {
5
      "path": "scoped-plugin.grit",
6
      "includes": ["src/**/*.ts", "!**/*.test.ts"]
7
    }
8
  ]
9
}
```
#9617 dcb99ef Thanks @faizkhairi! - Ported useAriaActivedescendantWithTabindex a11y rule to HTML.
#9496 1dfb829 Thanks @aviraldua93! - Added HTML support for the noAriaHiddenOnFocusable accessibility lint rule, which enforces that aria-hidden="true" is not set on focusable elements. Focusable elements include native interactive elements (<button>, <input>, <select>, <textarea>), elements with href (<a>, <area>), elements with tabindex >= 0, and editing hosts (contenteditable). Includes an unsafe fix to remove the aria-hidden attribute.
```
1

2
<button aria-hidden="true">Submit</button>
3

4

5
<div aria-hidden="true">decorative content</div>
```
#9792 f516854 Thanks @Maximiliano-Zeballos! - Added the useSemanticElements lint rule for HTML. The rule now detects the use of role attributes in HTML elements and suggests using semantic elements instead.

For example, the following code is now flagged:
```
1
<div role="navigation"></div>
```
The rule suggests using <nav> instead.
#9761 cbbb7d5 Thanks @Maximiliano-Zeballos! - Ported the useValidAriaProps lint rule to HTML. This rule checks that all aria-* attributes used in HTML elements are valid ARIA attributes as defined by the WAI-ARIA specification.
#9928 aa82576 Thanks @aviraldua93! - Ported useValidAriaValues to HTML. Biome now validates static aria-* attribute values in HTML elements against WAI-ARIA types, catching invalid values such as aria-hidden="yes".
#10562 6642895 Thanks @ematipico! - Promoted 73 nursery rules to stable groups.

Four rules were renamed as part of the promotion:
- noFloatingClasses is now noUnusedInstantiation, because the rule checks any discarded new expression, not only classes.
- noMultiStr is now noMultilineString.
- useFind is now useArrayFind.
- useSpread is now useSpreadOverApply, because the rule enforces spread call arguments over Function.apply(), not array or object spread.
Correctness

Promoted the following rules to the correctness group:
- noBeforeInteractiveScriptOutsideDocument
- noUnusedInstantiation
- useInlineScriptId (recommended, Next.js domain)
- noVueVIfWithVFor (recommended, Vue domain)
- useVueValidVBind (recommended, Vue domain)
- useVueValidVElse (recommended, Vue domain)
- useVueValidVElseIf (recommended, Vue domain)
- useVueValidVHtml (recommended, Vue domain)
- useVueValidVIf (recommended, Vue domain)
- useVueValidVOn (recommended, Vue domain)
- useVueValidVText (recommended, Vue domain)
- useVueValidTemplateRoot (recommended, Vue domain)
- useVueValidVCloak (recommended, Vue domain)
- useVueValidVOnce (recommended, Vue domain)
- useVueValidVPre (recommended, Vue domain)
- useVueVForKey (recommended, Vue domain)
- noDuplicateAttributes (recommended)
- noDuplicateArgumentNames (recommended)
- noDuplicateInputFieldNames (recommended)
- noDuplicateVariableNames (recommended)
- noDuplicateEnumValueNames (recommended)
- useLoneAnonymousOperation (recommended)
Suspicious

Promoted the following rules to the suspicious group:
- noShadow
- noUnnecessaryConditions
- noParametersOnlyUsedInRecursion
- noUnknownAttribute
- useArraySortCompare
- noForIn
- noDuplicatedSpreadProps
- noEqualsToNull
- noProto (recommended)
- noUndeclaredEnvVars (recommended, Turborepo domain)
- noReturnAssign (default severity: error)
- noDuplicateEnumValues (recommended)
- noVueArrowFuncInWatch (recommended, Vue domain)
- noNestedPromises
- noLeakedRender
- noDeprecatedMediaType (recommended)
- noDuplicateGraphqlOperationName
- useRequiredScripts
Style

Promoted the following rules to the style group:
- useVueMultiWordComponentNames (recommended, Vue domain)
- useVueDefineMacrosOrder
- noIncrementDecrement
- noContinue
- useSpreadOverApply
- noTernary
- noMultilineString
- noMultiAssign
- noExcessiveClassesPerFile
- noExcessiveLinesPerFile
- noVueOptionsApi
- useErrorCause
- useConsistentEnumValueType
- useConsistentMethodSignatures
- useGlobalThis (default severity: warn)
- useDestructuring
- useVueHyphenatedAttributes (recommended, Vue domain)
- useVueConsistentVBindStyle (recommended, Vue domain)
- useVueConsistentVOnStyle (recommended, Vue domain)
- noHexColors
- useConsistentGraphqlDescriptions
- noRootType
- useLoneExecutableDefinition
- useInputName
Complexity

Promoted the following rules to the complexity group:
- useArrayFind
- noRedundantDefaultExport (default severity: warn)
- noUselessReturn
- noDivRegex
Performance

Promoted the following rules to the performance group:
- noSyncScripts
- noJsxPropsBind
- useVueVapor
Security

Promoted the following rules to the security group:
- noScriptUrl (recommended)
A11y

Promoted the following rules to the a11y group:
- noAmbiguousAnchorText (recommended)
#10121 450f8e1 Thanks @jongwan56! - Biome now applies Git’s local exclude file when VCS ignore files are enabled. Files listed in .git/info/exclude are skipped the same way as files listed in .gitignore, including in linked worktrees.
#9397 d5913c9 Thanks @mvarendorff! - Added ignore option to the noUnusedVariables rule. The option allows excluding identifiers by providing a list of ignored names. It also allows excluding kinds of identifiers from this rule entirely, which may be useful when loading classes dynamically.

For example, unused classes as well as all unused variables, functions, etc. called “unused” may be ignored entirely with the following configuration:
```
1
{
2
  "ignore": {
3
    "*": ["unused"],
4
    "class": ["*"]
5
  }
6
}
```
#10089 71a21f0 Thanks @Netail! - Added the lint rule noLabelWithoutControl to HTML, which enforces that a label element or component has a text label and an associated input.
```
1
<label></label>
```
#10015 1828261 Thanks @Netail! - Added the HTML lint rule useAriaPropsSupportedByRole, which enforces that ARIA properties are valid for the roles that are supported by the element.
```
1
<a href="#" aria-checked></a>
```
#10234 1a51569 Thanks @ematipico! - Added the delimiterSpacing formatter option. This option inserts spaces inside delimiters (after the opening delimiter and before the closing delimiter) when the content fits on a single line. Empty delimiters are not affected, and no space is added before the opening delimiter. The specific delimiters affected depend on the language. It can be configured globally via formatter.delimiterSpacing or per-language via javascript.formatter.delimiterSpacing, json.formatter.delimiterSpacing, and css.formatter.delimiterSpacing. Defaults to false.
```
1
callFn(foo)
2
callFn( foo )
```
```
1
const arr = [1, 2, 3];
2
const arr = [ 1, 2, 3 ];
```
JavaScript

When enabled, Biome inserts spaces inside parentheses (e.g., foo( a, b )), square brackets (e.g., [ a, b ]), template literal interpolations (e.g., ${ expr }), and the logical NOT operator (e.g., ! x, but in chains only after the last one: !! x). Only applies when the content fits on a single line. Empty delimiters and the space before the opening delimiter are not affected.
```
1
if (condition) {}
2
if ( condition ) {}
```
```
1
`Hello ${name}!`
2
`Hello ${ name }!`
```
JSX

When enabled, Biome inserts spaces inside JSX expression braces (e.g., attr={ value }) and spread attributes (e.g., { ...props }). Only applies when the content fits on a single line. Empty delimiters are not affected.
```
1
<Foo bar={value} />
2
<Foo bar={ value } />
```
TypeScript

When enabled, Biome inserts spaces inside TypeScript angle brackets (e.g., foo< T >()), indexed access types (e.g., T[ K ]), mapped types, tuple types, type parameters, and index signatures. Only applies when the content fits on a single line. Empty delimiters are not affected.
```
1
type Result = Map<string, number>;
2
type Result = Map< string, number >;
```
JSON

When enabled, Biome inserts spaces inside square brackets when the content fits on a single line. Empty brackets are not affected.
```
1
[1, 2, 3]
2
[ 1, 2, 3 ]
```
CSS

When enabled, Biome inserts spaces inside parentheses and square brackets when the content fits on a single line. Empty delimiters are not affected.
```
1
rgba(0, 0, 0, 1)
2
rgba( 0, 0, 0, 1 )
```
```
1
[data-attr]
2
[ data-attr ]
```
#10461 6bac1c3 Thanks @TXWSLYF! - Implements #9445. Added the allowImplicit option to useIterableCallbackReturn. When enabled, callbacks can use return; to implicitly return undefined, matching ESLint’s array-callback-return rule.

#9571 5a8eb75 Thanks @dyc3! - Added configurable options to the useNumericSeparators rule. Users can now customize the minimum number of digits required before adding separators and the group length for each type of numeric literal (binary, octal, decimal, hexadecimal).

1
{
2
  "linter": {
3
    "rules": {
4
      "style": {
5
        "useNumericSeparators": {
6
          "level": "error",
7
          "options": {
8
            "decimal": {
9
              "minimumDigits": 7,
10
              "groupLength": 3
11
            },
12
            "hexadecimal": {
13
              "minimumDigits": 4,
14
              "groupLength": 2
15
            }
16
          }
17
        }
18
      }
19
    }
20
  }
21
}

#10067 6064312 Thanks @Netail! - Added the lint rule useFocusableInteractive to HTML, which enforces elements with an interactive role and interaction handler to be focusable.

Invalid:
```
1
<div role="button"></div>
```
#10026 fb42ac4 Thanks @Netail! - Added the HTML lint rule noNoninteractiveElementInteractions, which disallows use event handlers on non-interactive elements.

Invalid:
```
1
<div onclick="myFunction()">button</div>
```
#10000 2093e3e Thanks @Netail! - Added the new assist action useSortedEnumMembers, which sorts TypeScript & GraphQL enum members.

Invalid:
```
1
enum Role {
2
  SUPER_ADMIN
3
  ADMIN
4
  USER
5
  GOD
6
}
```
#10013 ad01d3d Thanks @Netail! - Added the HTML lint rule useValidAutocomplete, which enforces using valid values for the autocomplete attribute on input elements.
```
1
<input autocomplete="incorrect" />
```

Patch Changes

#10498 995c1ff Thanks @citadelgrad! - Added the nursery rule useReactFunctionComponentDefinition, which enforces a consistent function type for named React function components.

For example, the following snippet triggers the rule by default.
```
1
const MyComponent = (props) => {
2
  return <div>{props.name}</div>;
3
};
```
#9974 ff635a9 Thanks @pkallos! - Added ignoreMixedLogicalExpressions to useNullishCoalescing, partially addressing #9232. When enabled, Biome ignores || and ||= mixed with && in the same expression tree.
#10503 c656679 Thanks @Mokto! - Added the new nursery rule useSvelteRequireEachKey, a Svelte lint rule that reports {#each} blocks with item bindings that are missing a key.
#10516 0f29b83 Thanks @Dotify71! - Added useIncludes to the nursery group. This rule flags comparisons of String.prototype.indexOf() or Array.prototype.indexOf() against -1 and suggests replacing them with the clearer includes() / !includes() form.
#10487 0c03ee3 Thanks @Mokto! - Fixed a Svelte parser error that incorrectly required a binding variable after {:then} and {:catch}. Biome now correctly accepts {:then} and {:catch} without a binding, as well as the {#await expr then} and {#await expr catch} shorthand forms.
#10566 a4a294c Thanks @dyc3! - Fixed useVueHyphenatedAttributes: The rule now only reports diagnostics in Vue files and ignores SVG elements.
#10565 72ccf3b Thanks @dyc3! - Fixed useVueConsistentVBindStyle: The rule no longer reports argument-less v-bind directives because they cannot be converted to shorthand syntax.
#10591 6e8557b Thanks @xsourabhsharma! - Fixed #10563: Biome now parses comma-separated CSS Modules composes values, such as composes: classA from "./a.css", classB from "./b.css";.
#10603 174b21b Thanks @denbezrukov! - Fixed CSS formatting for grid-template-areas declarations with comments before multiline values. Biome now keeps grid area rows aligned instead of adding an extra declaration-boundary indent.
```
1
.grid {
2
  grid-template-areas:
3
/* row */
4
      "header header"
5
      "footer footer";
6
    "header header"
7
    "footer footer";
8
}
```
#10542 c3f07f7 Thanks @dyc3! - Fixed #10513: Biome no longer rejects literal \u sequences in quoted HTML attribute values.
#10108 24e51d6 Thanks @IxxyDev! - Fixed #6611: noUnnecessaryConditions now uses type information to detect more redundant conditions, including ?., ??, ||, &&, comparisons against null/undefined on non-nullish operands, and case clauses that can never match the switch value.
#10568 eb1ed0e Thanks @harsha-cpp! - Fixed #10564: useAriaPropsForRole no longer reports false positives for Vue v-bind shorthand bindings (:aria-checked, :aria-level, etc.).
#10570 2ceb4fe Thanks @Conaclos! - Improved noTsIgnore. The rule now reports more precisely the range of the @ts-ignore comment.
#10520 b55d10f Thanks @dyc3! - Fixed #10519: Vue v-on event handlers with multiple inline statements are now parsed consistently with Vue.
#10204 ebbf0bd Thanks @ematipico! - Improved the performance of the Biome linter. The improvements are more visible in bigger projects that have more than ~1k files. Early tests showed that in a code base with ~2k files, Biome took less than 26% of time to finish the command.
#10546 e39bb2c Thanks @tim-we! - Fixed #10536: noUnknownFunction no longer flagged CSS contrast-color() as unknown. contrast-color() is Baseline 2026.
#8012 2be0264 Thanks @denbezrukov! - Improved the performance of the formatter in some cases. The formatter is now up to ~20% faster at formatting files.
#10467 9a5855e Thanks @Netail! - Added a new nursery rule noRestrictedDependencies, which flags imports and package.json dependency entries that have better alternatives in e18e’s module replacement data.

For example, the package globby is reported because there’s a better alternative:
```
1
import glob from "globby";
```
```
1
{
2
  "dependencies": {
3
    "globby": "x.x.x"
4
  }
5
}
```
#10470 84b43c5 Thanks @ShaharAviram1! - Fixed #10447: now the rule noProcessEnv detects the use of env when it’s imported from process and node:process.
#10556 7ff6b16 Thanks @ematipico! - Fixed #10492: Biome no longer crashes with a stack overflow on certain code when a type-aware rule such as noFloatingPromises, noMisusedPromises, or noUnnecessaryConditions is enabled. For example, the following code used to crash Biome:
```
1
function f(visitor) {
2
  let ctrl = visitor();
3
  for (const x of [0]) ctrl = ctrl();
4
}
```

#10532 1da3c75 Thanks @denbezrukov! - CSS declarations with comments before : or after !important now preserve spaces before : and ;.

1
.selector {
2
  padding/* name */: 1px;
3
  color: red !important /* note */;
4
  padding/* name */ : 1px;
5
  color: red !important /* note */ ;
6
}

#10491 a1b5834 Thanks @Mokto! - Fixed the Svelte parser rejecting {#each} blocks where the binding uses object destructuring with property renaming, e.g. {#each items as { id, component: Filter }}. Biome now correctly parses and formats these rename bindings.
#10490 99bc7df Thanks @Mokto! - Fixed the CSS parser rejecting comma-separated selector lists inside :global() and :local() pseudo-class functions. Biome now correctly parses :global(.foo, .bar).
#10543 c394fae Thanks @mangod12! - Fixed #10477: The RDJSON reporter now emits code replacement text for fix suggestions instead of the human-readable fix description.
#10530 e8e1e6a Thanks @Conaclos! - Fixed #10493: useImportType now correctly separates types from a default named import when all imports are types and the style option is set to separatedType.
#10555 263c7cc Thanks @Mokto! - Improved Svelte lint rule accuracy for quoted attribute values containing {expression} interpolations.
- noRedundantAlt no longer emits false positives when the alt text contains an interpolation, e.g. alt="image of {person}".
- useButtonType no longer emits false positives for dynamic button types written as type="{dynamicType}".
- noScriptUrl no longer emits false positives for dynamic hrefs such as href="{url}".
#10489 96ef9a4 Thanks @Mokto! - Fixed Svelte {#each} parser incorrectly rejecting TypeScript as const type assertions in the iterable expression. Biome now correctly parses {#each arr as const as item}.
#10539 935c59a Thanks @dyc3! - Improved how diagnostics print long lines of code, for example minified files where the entire source code is printed in one line.

All versions since 2.4.12

2.4.12

Patch Changes

2.4.13

Patch Changes

2.4.14

Patch Changes

2.4.15

Patch Changes

2.4.16

Patch Changes

2.5.0 Latest

Minor Changes

Correctness

Suspicious

Style

Complexity

Performance

Security

A11y

JavaScript

JSX

TypeScript

JSON

CSS

Patch Changes