Version History

2.2.4 Latest

Patch Changes

#7453 aa8cea3 Thanks @arendjr! - Fixed #7242: Aliases specified in package.json’s imports section now support having multiple targets as part of an array.
#7454 ac17183 Thanks @arendjr! - Greatly improved performance of noImportCycles by eliminating allocations.

In one repository, the total runtime of Biome with only noImportCycles enabled went from ~23s down to ~4s.
#7447 7139aad Thanks @rriski! - Fixes #7446. The GritQL $... spread metavariable now correctly matches members in object literals, aligning its behavior with arrays and function calls.

#6710 98cf9af Thanks @arendjr! - Fixed #4723: Type inference now recognises index signatures and their accesses when they are being indexed as a string.

Example

1
type BagOfPromises = {
2
  // This is an index signature definition. It declares that instances of type
3
  // `BagOfPromises` can be indexed using arbitrary strings.
4
  [property: string]: Promise<void>;
5
};
6

7
let bag: BagOfPromises = {};
8
// Because `bag.iAmAPromise` is equivalent to `bag["iAmAPromise"]`, this is
9
// considered an access to the string index, and a Promise is expected.
10
bag.iAmAPromise;

#7415 d042f18 Thanks @qraqras! - Fixed #7212, now the useOptionalChain rule recognizes optional chaining using typeof (e.g., typeof foo !== 'undefined' && foo.bar).
#7419 576baf4 Thanks @Conaclos! - Fixed #7323. noUnusedPrivateClassMembers no longer reports as unused TypeScript private members if the rule encounters a computed access on this.

In the following example, member as previously reported as unused. It is no longer reported.
```
1
class TsBioo {
2
  private member: number;
3

4
  set_with_name(name: string, value: number) {
5
    this[name] = value;
6
  }
7
}
```
351bccd Thanks @ematipico! - Added the new nursery lint rule noJsxLiterals, which disallows the use of string literals inside JSX.

The rule catches these cases:
```
1
<>
2
  <div>test</div> {/* test is invalid */}
3
  <>test</>
4
  <div>
5
    {/* this string is invalid */}
6
    asdjfl test foo
7
  </div>
8
</>
```
#7406 b906112 Thanks @mdevils! - Fixed an issue (#6393) where the useHookAtTopLevel rule reported excessive diagnostics for nested hook calls.

The rule now reports only the offending top-level call site, not sub-hooks of composite hooks.
```
1
// Before: reported twice (useFoo and useBar).
2
function useFoo() {
3
  return useBar();
4
}
5
function Component() {
6
  if (cond) useFoo();
7
}
8
// After: reported once at the call to useFoo().
```
#7461 ea585a9 Thanks @arendjr! - Improved performance of noPrivateImports by eliminating allocations.

In one repository, the total runtime of Biome with only noPrivateImports enabled went from ~3.2s down to ~1.4s.
351bccd Thanks @ematipico! - Fixed #7411. The Biome Language Server had a regression where opening an editor with a file already open wouldn’t load the project settings correctly.
#7142 53ff5ae Thanks @Netail! - Added the new nursery rule noDuplicateDependencies, which verifies that no dependencies are duplicated between the bundledDependencies, bundleDependencies, dependencies, devDependencies, overrides, optionalDependencies, and peerDependencies sections.

For example, the following snippets will trigger the rule:
```
1
{
2
  "dependencies": {
3
    "foo": ""
4
  },
5
  "devDependencies": {
6
    "foo": ""
7
  }
8
}
```
```
1
{
2
  "dependencies": {
3
    "foo": ""
4
  },
5
  "optionalDependencies": {
6
    "foo": ""
7
  }
8
}
```
```
1
{
2
  "dependencies": {
3
    "foo": ""
4
  },
5
  "peerDependencies": {
6
    "foo": ""
7
  }
8
}
```
351bccd Thanks @ematipico! - Fixed #3824. Now the option CLI --color is correctly applied to logging too.

2.2.3

Patch Changes

#7353 4d2b719 Thanks @JeetuSuthar! - Fixed #7340: The linter now allows the navigation property for view-transition in CSS.

Previously, the linter incorrectly flagged navigation: auto as an unknown property. This fix adds navigation to the list of known CSS properties, following the CSS View Transitions spec.
#7275 560de1b Thanks @arendjr! - Fixed #7268: Files that are explicitly passed as CLI arguments are now correctly ignored if they reside in an ignored folder.
#7358 963a246 Thanks @ematipico! - Fixed #7085, now the rule noDescendingSpecificity correctly calculates the specificity of selectors when they are included inside a media query.
#7387 923674d Thanks @qraqras! - Fixed #7381, now the useOptionalChain rule recognizes optional chaining using Yoda expressions (e.g., undefined !== foo && foo.bar).
#7316 f9636d5 Thanks @Conaclos! - Fixed #7289. The rule useImportType now inlines import type into import { type } when the style option is set to inlineType.

Example:
```
1
import type { T } from "mod";
2
// becomes
3
import { type T } from "mod";
```
#7350 bb4d407 Thanks @siketyan! - Fixed #7261: two characters ・ (KATAKANA MIDDLE DOT, U+30FB) and ･ (HALFWIDTH KATAKANA MIDDLE DOT, U+FF65) are no longer considered as valid characters in identifiers. Property keys containing these character(s) are now preserved as string literals.
#7377 811f47b Thanks @ematipico! - Fixed a bug where the Biome Language Server didn’t correctly compute the diagnostics of a monorepo setting, caused by an incorrect handling of the project status.
#7245 fad34b9 Thanks @kedevked! - Added the new lint rule useConsistentArrowReturn.

This rule enforces a consistent return style for arrow functions.

Invalid
```
1
const f = () => {
2
  return 1;
3
};
```
This rule is a port of ESLint’s arrow-body-style rule.

#7370 e8032dd Thanks @fireairforce! - Support dynamic import defer and import source. The syntax looks like:

1
import.source("foo");
2
import.source("x", { with: { attr: "val" } });
3
import.defer("foo");
4
import.defer("x", { with: { attr: "val" } });

#7369 b1f8cbd Thanks @siketyan! - Range suppressions are now supported for Grit plugins.

For JavaScript, you can suppress a plugin as follows:

1
// biome-ignore-start lint/plugin/preferObjectSpread: reason
2
Object.assign({ foo: "bar" }, baz);
3
// biome-ignore-end lint/plugin/preferObjectSpread: reason

For CSS, you can suppress a plugin as follows:

1
body {
2
  /* biome-ignore-start lint/plugin/useLowercaseColors: reason */
3
  color: #fff;
4
  /* biome-ignore-end lint/plugin/useLowercaseColors: reason */
5
}

#7384 099507e Thanks @ematipico! - Reduced the severity of certain diagnostics emitted when Biome deserializes the configuration files. Now these diagnostics are emitted as Information severity, which means that they won’t interfere when running commands with --error-on-warnings
#7302 2af2380 Thanks @unvalley! - Fixed #7301: useReadonlyClassProperties now correctly skips JavaScript files.
#7288 94d85f8 Thanks @ThiefMaster! - Fixed #7286. Files are now formatted with JSX behavior when javascript.parser.jsxEverywhere is explicitly set.

Previously, this flag was only used for parsing, but not for formatting, which resulted in incorrect formatting of conditional expressions when JSX syntax is used in .js files.
#7311 62154b9 Thanks @qraqras! - Added the new nursery rule noUselessCatchBinding. This rule disallows unnecessary catch bindings.
```
1
try {
2
    // Do something
3
 } catch (unused) {}
4
 } catch {}
```

#7349 45c1dfe Thanks @ematipico! - Fixed #4298. Biome now correctly formats CSS declarations when it contains one single value:

1
.bar {
2
  --123456789012345678901234567890: var(--1234567890123456789012345678901234567);
3
  --123456789012345678901234567890: var(
4
    --1234567890123456789012345678901234567
5
  );
6
}

#7295 7638e84 Thanks @ematipico! - Fixed #7130. Removed the emission of a false-positive diagnostic. Biome no longer emits the following diagnostic:

1
lib/main.ts:1:5 suppressions/unused ━━━━━━━━━━━━━━━━━━━━━━━━━
2

3
  ⚠ Suppression comment has no effect because the tool is not enabled.
4

5
  > 1 │ /** biome-ignore-all assist/source/organizeImports: For the lib root file, we don't want to organize exports */
6
      │     ^^^^^^^^^^^^^^^^

#7377 811f47b Thanks @ematipico! - Fixed #7371 where the Biome Language Server didn’t correctly recompute the diagnostics when updating a nested configuration file.
#7348 ac27fc5 Thanks @ematipico! - Fixed #7079. Now the rule useSemanticElements doesn’t trigger components and custom elements.
#7389 ab06a7e Thanks @Conaclos! - Fixed #7344. useNamingConvention no longer reports interfaces defined in global declarations.

Interfaces declared in global declarations augment existing interfaces. Thus, they must be ignored.

In the following example, useNamingConvention reported HTMLElement. It is now ignored.
```
1
export {};
2
declare global {
3
  interface HTMLElement {
4
    foo(): void;
5
  }
6
}
```
#7315 4a2bd2f Thanks @vladimir-ivanov! - Fixed #7310: useReadonlyClassProperties correctly handles nested assignments, avoiding false positives when a class property is assigned within another assignment expression.

Example of code that previously triggered a false positive but is now correctly ignored:
```
1
class test {
2
  private thing: number = 0; // incorrectly flagged
3

4
  public incrementThing(): void {
5
    const temp = { x: 0 };
6
    temp.x = this.thing++;
7
  }
8
}
```

2.2.2

Patch Changes

#7266 b270bb5 Thanks @ematipico! - Fixed an issue where Biome got stuck when analyzing some files. This is usually caused by a bug in the inference engine. Now Biome has some guards in place in case the number of types grows too much, and if that happens, a diagnostic is emitted and the inference is halted.
#7281 6436180 Thanks @ematipico! - Fixed an issue where the function scanProject wouldn’t work as expected.
#7285 1511d0c Thanks @rriski! - Partially fixed #6782: JSX node kinds are now supported in GritQL AST nodes.
#7249 dff85c0 Thanks @ematipico! - Fixed #748, where Biome Language Server didn’t show the unsafe fixes when requesting the quick fixes. Now all LSP editors will show also opt-in, unsafe fixes.
#7266 b270bb5 Thanks @ematipico! - Fixed #7020: Resolved an issue with analysing types of static member expressions involving unions. If the object type was a union that referenced nested unions, it would trigger an infinite loop as it tried to keep expanding nested unions, and the set of types would grow indefinitely.
#7209 679b70e Thanks @patrickshipe! - Resolved an overcorrection in useImportExtensions when importing explicit index files.

Imports that explicitly reference an index file are now preserved and no longer rewritten to nested index paths.

Example
```
1
// Before
2
      import "./sub/index";
3
      import "./sub/index/index.js";
4

5
// After
6
      import "./sub/index";
7
      import "./sub/index.js";
```
#7270 953f9c6 Thanks @arendjr! - Fixed #6172: Resolved an issue with inferring types for rest parameters. This issue caused rest-parameter types to be incorrect, and in some cases caused extreme performance regressions in files that contained many methods with rest-parameter definitions.
#7234 b7aa111 Thanks @JeetuSuthar! - Fixed #7233: The useIndexOf rule now correctly suggests using indexOf() instead of findIndex().

The diagnostic message was incorrectly recommending Array#findIndex() over Array#indexOf(), when it should recommend the opposite for simple equality checks.
#7283 0b07f45 Thanks @ematipico! - Fixed #7236. Now Biome correctly migrates JSONC configuration files when they are passed using --config-path.
#7239 1d643d8 Thanks @minht11! - Fixed an issue where Svelte globals ($state and so on) were not properly recognized inside .svelte.test.ts/js and .svelte.spec.ts/js files.
#7264 62fdbc8 Thanks @ematipico! - Fixed a regression where when using --log-kind-pretty wasn’t working anymore as expected.
#7244 660031b Thanks @JeetuSuthar! - Fixed #7225: The noExtraBooleanCast rule now preserves parentheses when removing Boolean calls inside negations.
```
1
// Before
2
!Boolean(b0 && b1);
3
// After
4
!(b0 && b1); // instead of !b0 && b1
```
#7298 46a8e93 Thanks @unvalley! - Fixed #6695: useNamingConvention now correctly reports TypeScript parameter properties with modifiers.

Previously, constructor parameter properties with modifiers like private or readonly were not checked against naming conventions. These properties are now treated consistently with regular class properties.

2.2.0

Minor Changes

#5506 1f8755b Thanks @sakai-ast! - The noRestrictedImports rule has been enhanced with a new patterns option. This option allows for more flexible and powerful import restrictions using gitignore-style patterns.

You can now define patterns to restrict entire groups of modules. For example, you can disallow imports from any path under import-foo/ except for import-foo/baz.
```
1
{
2
  "options": {
3
    "patterns": [
4
      {
5
        "group": ["import-foo/*", "!import-foo/baz"],
6
        "message": "import-foo is deprecated, except for modules in import-foo/baz."
7
      }
8
    ]
9
  }
10
}
```
Invalid examples
```
1
import foo from "import-foo/foo";
2
import bar from "import-foo/bar";
```
Valid examples
```
1
import baz from "import-foo/baz";
```
Additionally, the patterns option introduces importNamePattern to restrict specific import names using regular expressions. The following example restricts the import names that match x , y or z letters from modules under import-foo/.
```
1
{
2
  "options": {
3
    "patterns": [
4
      {
5
        "group": ["import-foo/*"],
6
        "importNamePattern": "[xyz]"
7
      }
8
    ]
9
  }
10
}
```
Invalid examples
```
1
import { x } from "import-foo/foo";
```
Valid examples
```
1
import { foo } from "import-foo/foo";
```
Furthermore, you can use the invertImportNamePattern boolean option to reverse this logic. When set to true, only the import names that match the importNamePattern will be allowed. The following configuration only allows the import names that match x , y or z letters from modules under import-foo/.
```
1
{
2
  "options": {
3
    "patterns": [
4
      {
5
        "group": ["import-foo/*"],
6
        "importNamePattern": "[xyz]",
7
        "invertImportNamePattern": true
8
      }
9
    ]
10
  }
11
}
```
Invalid examples
```
1
import { foo } from "import-foo/foo";
```
Valid examples
```
1
import { x } from "import-foo/foo";
```
#6506 90c5d6b Thanks @nazarhussain! - Allow customization of the sort order for different sorting actions. These actions now support a sort option:
- assist/source/useSortedKeys now has a sortOrder option
- assist/source/useSortedAttributes now has a sortOrder option
- assist/source/organizeImports now has an identifierOrder option
For each of these options, the supported values are the same:
1. natural. Compares two strings using a natural ASCII order. Uppercase letters come first (e.g. A < a < B < b) and number are compared in a human way (e.g. 9 < 10). This is the default value.
2. **lexicographic **. Strings are ordered lexicographically by their byte values. This orders Unicode code points based on their positions in the code charts. This is not necessarily the same as “alphabetical” order, which varies by language and locale.
#7159 df3afdf Thanks @ematipico! - Added the new rule useBiomeIgnoreFolder. Since v2.2, Biome correctly prevents the indexing and crawling of folders.

However, the correct pattern has changed. This rule attempts to detect incorrect usage, and promote the new pattern:
biome.json
```
1
{
2
  "files": {
3
    "includes": [
4
      "!dist/**",
5
      "!**/fixtures/**",
6
      "!dist",
7
      "!**/fixtures",
8
    ]
9
  }
10
}
```
#6989 85b1128 Thanks @arendjr! - Fixed minor inconsistencies in how files.includes was being handled.

Previously, Biome sometimes failed to properly ignore the contents of a folder if you didn’t specify the /** at the end of a glob pattern. This was unfortunate, because it meant we still had to traverse the folder and then apply the glob to every entry inside it.

This is no longer an issue and we now recommend to ignore folders without using the /** suffix.
#7118 a78e878 Thanks @avshalomt2! - Added support for .graphqls files. Biome can now format and lint GraphQL files that have the extension .graphqls

#6159 f02a296 Thanks @bavalpey! - Added a new option to Biome’s JavaScript formatter, javascript.formatter.operatorLinebreak, to configure whether long lines should be broken before or after binary operators.

For example, the following configuration:

1
{
2
  formatter: {
3
    javascript: {
4
      operatorLinebreak: "before", // defaults to "after"
5
    },
6
  },
7
}

Will cause this JavaScript file:

1
const VERY_LONG_CONDITION_1234123412341234123412341234 = false;
2

3
if (
4
  VERY_LONG_CONDITION_1234123412341234123412341234 &&
5
  VERY_LONG_CONDITION_1234123412341234123412341234 &&
6
  VERY_LONG_CONDITION_1234123412341234123412341234 &&
7
  VERY_LONG_CONDITION_1234123412341234123412341234
8
) {
9
  console.log("DONE");
10
}

to be formatted like this:

1
const VERY_LONG_CONDITION_1234123412341234123412341234 = false;
2

3
if (
4
  VERY_LONG_CONDITION_1234123412341234123412341234 &&
5
  VERY_LONG_CONDITION_1234123412341234123412341234 &&
6
  VERY_LONG_CONDITION_1234123412341234123412341234 &&
7
  VERY_LONG_CONDITION_1234123412341234123412341234
8
) {
9
  console.log("DONE");
10
}

#7137 a653a0f Thanks @ematipico! - Promoted multiple lint rules from nursery to stable groups and renamed several rules for consistency.

Promoted rules

The following rules have been promoted from nursery to stable groups:

CSS
- Promoted noImportantStyles to the complexity group.
- Promoted noUnknownAtRules to the suspicious group.
GraphQL
- Promoted useGraphqlNamedOperations to the correctness group.
- Promoted useGraphqlNamingConvention to the style group.
JavaScript/TypeScript
- Promoted noExcessiveLinesPerFunction to the complexity group.
- Promoted noImplicitCoercions to the complexity group.
- Promoted useIndexOf to the complexity group.
- Promoted noGlobalDirnameFilename to the correctness group.
- Promoted noNestedComponentDefinitions to the correctness group.
- Promoted noProcessGlobal to the correctness group.
- Promoted noReactPropAssignments to the correctness group.
- Promoted noRestrictedElements to the correctness group.
- Promoted noSolidDestructuredProps to the correctness group.
- Promoted useJsonImportAttributes to the correctness group.
- Promoted useParseIntRadix to the correctness group.
- Promoted useSingleJsDocAsterisk to the correctness group.
- Promoted useUniqueElementIds to the correctness group.
- Promoted noAwaitInLoops to the performance group.
- Promoted noUnwantedPolyfillio to the performance group.
- Promoted useGoogleFontPreconnect to the performance group.
- Promoted useSolidForComponent to the performance group.
- Promoted noMagicNumbers to the style group.
- Promoted useConsistentObjectDefinitions to the style group.
- Promoted useExportsLast to the style group.
- Promoted useGroupedAccessorPairs to the style group.
- Promoted useNumericSeparators to the style group.
- Promoted useObjectSpread to the style group.
- Promoted useReadonlyClassProperties to the style group.
- Promoted useSymbolDescription to the style group.
- Promoted useUnifiedTypeSignatures to the style group.
- Promoted noBitwiseOperators to the suspicious group.
- Promoted noConstantBinaryExpressions to the suspicious group.
- Promoted noTsIgnore to the suspicious group.
- Promoted noUnassignedVariables to the suspicious group.
- Promoted noUselessRegexBackrefs to the suspicious group.
- Promoted noUselessEscapeInString to the suspicious group.
- Promoted useIterableCallbackReturn to the suspicious group.
- Promoted useStaticResponseMethods to the suspicious group.
Renamed rules

The following rules have been renamed during promotion. The migration tool will automatically update your configuration:
- Renamed noAwaitInLoop to noAwaitInLoops.
- Renamed noConstantBinaryExpression to noConstantBinaryExpressions.
- Renamed noDestructuredProps to noSolidDestructuredProps.
- Renamed noImplicitCoercion to noImplicitCoercions.
- Renamed noReactPropAssign to noReactPropAssignments.
- Renamed noUnknownAtRule to noUnknownAtRules.
- Renamed noUselessBackrefInRegex to noUselessRegexBackrefs.
- Renamed useAdjacentGetterSetter to useGroupedAccessorPairs.
- Renamed useConsistentObjectDefinition to useConsistentObjectDefinitions.
- Renamed useConsistentResponse to useStaticResponseMethods.
- Renamed useForComponent to useSolidForComponent.
- Renamed useJsonImportAttribute to useJsonImportAttributes.
- Renamed useNamedOperation to useGraphqlNamedOperations.
- Renamed useNamingConvention to useGraphqlNamingConvention.
- Renamed useUnifiedTypeSignature to useUnifiedTypeSignatures.
Configuration files using the old rule names will need to be updated. Use the migration tool to automatically update your configuration:
Terminal window
```
1
biome migrate --write
```
#7159 df3afdf Thanks @ematipico! - Added the new rule noBiomeFirstException. This rule prevents the incorrect usage of patterns inside files.includes.

This rule catches if the first element of the array contains !. This mistake will cause Biome to analyze no files:
biome.json
```
1
{
2
  files: {
3
    includes: ["!dist/**"], // this is an error
4
  },
5
}
```
#6923 0589f08 Thanks @ptkagori! - Added Qwik Domain to Biome

This release introduces **Qwik domain support ** in Biome, enabling Qwik developers to use Biome as a linter and formatter for their projects.
- Added the Qwik domain infrastructure to Biome.
- Enabled the following rules for Qwik:
  - useJsxKeyInIterable
  - noReactSpecificProps
#6989 85b1128 Thanks @arendjr! - Fixed #6965: Implemented smarter scanner for project rules.

Previously, if project rules were enabled, Biome’s scanner would scan all dependencies regardless of whether they were used by/reachable from source files or not. While this worked for a first version, it was far from optimal.

The new scanner first scans everything listed under the files.includes setting, and then descends into the dependencies that were discovered there, including transitive dependencies. This has three main advantages:
- Dependencies that are not reachable from your source files don’t get indexed.
- Dependencies that have multiple type definitions, such as those with separate definitions for CommonJS and ESM imports, only have the relevant definitions indexed.
- If vcs.useIgnoreFile is enabled, .gitignore gets respected as well. Assuming you have folders such as build/ or dist/ configured there, those will be automatically ignored by the scanner.
The change in the scanner also has a more nuanced impact: Previously, if you used files.includes to ignore a file in an included folder, the scanner would still index this file. Now the file is fully ignored, unless you import it.

As a user you should notice better scanner performance (if you have project rules enabled), and hopefully you need to worry less about configuring files.experimentalScannerIgnores. Eventually our goal is still to deprecate that setting, so if you’re using it today, we encourage you to see which ignores are still necessary there, and whether you can achieve the same effect by ignoring paths using files.includes instead.

None of these changes affect the scanner if no project rules are enabled.

#6731 d6a05b5 Thanks @ematipico! - The --reporter=summary has been greatly enhanced. It now shows the list of files that contains violations, the files shown are clickable and can be opened from the editor.

Below an example of the new version:

1
reporter/parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
2

3
  i The following files have parsing errors.
4

5
  - index.css
6

7
reporter/format ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
8

9
  i The following files needs to be formatted.
10

11
  - index.css
12
  - index.ts
13
  - main.ts
14

15
reporter/violations ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
16

17
  i Some lint rules or assist actions reported some violations.
18

19
  Rule Name                                        Diagnostics
20

21
  lint/correctness/noUnknownFunction               14 (2 error(s), 12 warning(s), 0 info(s))
22
  lint/suspicious/noImplicitAnyLet                 16 (12 error(s), 4 warning(s), 0 info(s))
23
  lint/suspicious/noDoubleEquals                   8 (8 error(s), 0 warning(s), 0 info(s))
24
  assist/source/organizeImports                    2 (2 error(s), 0 warning(s), 0 info(s))
25
  lint/suspicious/noRedeclare                      12 (12 error(s), 0 warning(s), 0 info(s))
26
  lint/suspicious/noDebugger                       8 (8 error(s), 0 warning(s), 0 info(s))

#6896 527db7f Thanks @ematipico! - Added new functions to the @biomejs/wasm-* packages:
- fileExists: returns whether the input file exists in the workspace.
- isPathIgnored: returns whether the input path is ignored.
- updateModuleGraph: updates the internal module graph of the input path.
- getModuleGraph: it returns a serialized version of the internal module graph.
- scanProject: scans the files and directories in the project to build the internal module graph.

#6398 d1a315d Thanks @josh-! - Added support for tracking stable results in user-provided React hooks that return objects to useExhaustiveDependencies to compliment existing support for array return values. For example:

1
{
2
  // rule options
3
  useExhaustiveDependencies: {
4
    level: "error",
5
    options: {
6
      hooks: [
7
        {
8
          name: "useCustomHook",
9
          stableResult: ["setMyState"],
10
        },
11
      ],
12
    },
13
  },
14
}

This will allow the following to be validated:

1
const { myState, setMyState } = useCustomHook();
2
const toggleMyState = useCallback(() => {
3
  setMyState(!myState);
4
}, [myState]); // Only `myState` needs to be specified here.

#7201 2afaa49 Thanks @Conaclos! - Implemented #7174. useConst no longer reports variables that are read before being written.

Previously, useConst reported uninitialised variables that were read in an inner function before being written, as shown in the following example:
```
1
let v;
2
function f() {
3
  return v;
4
}
5
v = 0;
```
This can produce false positives in the case where f is called before v has been written, as in the following code:
```
1
let v;
2
function f() {
3
  return v;
4
}
5
console.log(f()); // print `undefined`
6
v = 0;
```
Although this is an expected behavior of the original implementation, we consider it problematic since the rule’s fix is marked as safe. To avoid false positives like this, the rule now ignores the previous examples. However, this has the disadvantage of resulting in false negatives, such as not reporting the first example.

Patch Changes

#7156 137d111 Thanks @ematipico! - Fixed #7152. Now the rule noDuplicateFontNames correctly detects font names with spaces e.g. Liberation Mono. The diagnostic of the rule now points to the first instances of the repeated font.

The following example doesn’t trigger the rule anymore:
```
1
c {
2
  font-family:
3
    SF Mono,
4
    Liberation Mono,
5
    sans-serif;
6
}
7
d {
8
  font:
9
    1em SF Mono,
10
    Liberation Mono,
11
    sans-serif;
12
}
```

#6907 7331bb9 Thanks @ematipico! - Added a new experimental option that allows parsing of .html files that contain interpolation syntax.

1
{
2
  html: {
3
    // This is the new, experimental option.
4
    parser: {
5
      interpolation: true,
6
    },
7
  },
8
}

1
<h1>{{ $title }}</h1>

#7124 3f436b8 Thanks @Jayllyz! - Added the rule useMaxParams.

This rule enforces a maximum number of parameters for functions to improve code readability and maintainability. Functions with many parameters are difficult to read, understand, and maintain because they require memorizing parameter order and types.

1
// Invalid - too many parameters (default max: 4)
2
function processData(
3
  name,
4
  age,
5
  email,
6
  phone,
7
  address,
8
  city,
9
  country,
10
  zipCode,
11
) {
12
  // ...
13
}
14

15
// Valid - within parameter limit
16
function processData(userData) {
17
  const { name, age, email, phone, address, city, country, zipCode } =
18
    userData;
19
  // ...
20
}
21

22
function calculateSum(a, b, c) {
23
  return a + b + c;
24
}

#7161 1a14a59 Thanks @ematipico! - Fixed #7160. Now Biome correctly computes ignored files when using formatter.includes, linter.includes and assist.includes inside nested configurations that use "extends": "//".
#7081 a081bbe Thanks @Jayllyz! - Added the rule noNextAsyncClientComponent.

This rule prevents the use of async functions for client components in Next.js applications. Client components marked with “use client” directive should not be async as this can cause hydration mismatches, break component rendering lifecycle, and lead to unexpected behavior with React’s concurrent features.
```
1
"use client";
2

3
// Invalid - async client component
4
export default async function MyComponent() {
5
  return <div>Hello</div>;
6
}
7

8
// Valid - synchronous client component
9
export default function MyComponent() {
10
  return <div>Hello</div>;
11
}
```
#7171 5241690 Thanks @siketyan! - Fixed #7162: The noUndeclaredDependencies rule now considers a type-only import as a dev dependency.

For example, the following code is no longer reported:

package.json:
```
1
{
2
  "devDependencies": {
3
    "type-fest": "*"
4
  }
5
}
```
foo.ts:
```
1
import type { SetRequired } from "type-fest";
```
Note that you still need to declare the package in the devDependencies section in package.json.

2.1.4

Patch Changes

#7121 b9642ab Thanks @arendjr! - Fixed #7111: Imported symbols using aliases are now correctly recognised.
#7103 80515ec Thanks @omasakun! - Fixed #6933 and #6994.

When the values of private member assignment expressions, increment expressions, etc. are used, those private members are no longer marked as unused.
#6887 0cc38f5 Thanks @ptkagori! - Added the noQwikUseVisibleTask rule to Qwik.

This rule is intended for use in Qwik applications to warn about the use of useVisibleTask$() functions which require careful consideration before use.

Invalid:
```
1
useVisibleTask$(() => {
2
  console.log("Component is visible");
3
});
```
Valid:
```
1
useTask$(() => {
2
  console.log("Task executed");
3
});
```
#7084 50ca155 Thanks @ematipico! - Added the new nursery rule noUnnecessararyConditions, which detects whenever some conditions don’t change during the life cycle of the program, and truthy or false, hence deemed redundant.

For example, the following snippets will trigger the rule:
```
1
// Always truthy literal conditions
2
if (true) {
3
  console.log("always runs");
4
}
```
```
1
// Unnecessary condition on constrained string type
2
function foo(arg: "bar" | "baz") {
3
  if (arg) {
4
    // This check is unnecessary
5
  }
6
}
```
#6887 0cc38f5 Thanks @ptkagori! - Added the useImageSize rule to Biome.

The useImageSize rule enforces the use of width and height attributes on <img> elements for performance reasons. This rule is intended to prevent layout shifts and improve Core Web Vitals by ensuring images have explicit dimensions.

Invalid:
```
1
<img src="/image.png" />
2
<img src="https://example.com/image.png" />
3
<img src="/image.png" width="200" />
4
<img src="/image.png" height="200" />
```
Valid:
```
1
<img width="200" height="600" src="/static/images/portrait-01.webp" />
2
<img width="100" height="100" src="https://example.com/image.png" />
```
#6887 0cc38f5 Thanks @ptkagori! - Added the useAnchorHref rule to Biome.

The useAnchorHref rule enforces the presence of an href attribute on <a> elements in JSX. This rule is intended to ensure that anchor elements are always valid and accessible.

Invalid:
```
1
<a>Link</a>
```
```
1
<a target="_blank">External</a>
```
Valid:
```
1
<a href="/home">Home</a>
```
```
1
<a href="https://example.com" target="_blank">
2
  External
3
</a>
```
#7100 29fcb05 Thanks @Jayllyz! - Added the rule noNonNullAssertedOptionalChain.

This rule prevents the use of non-null assertions (!) immediately after optional chaining expressions ( ?.). Optional chaining is designed to safely handle nullable values by returning undefined when the chain encounters null or undefined. Using a non-null assertion defeats this purpose and can lead to runtime errors.
```
1
// Invalid - non-null assertion after optional chaining
2
obj?.prop!;
3
obj?.method()!;
4
obj?.[key]!;
5
obj?.prop!;
6

7
// Valid - proper optional chaining usage
8
obj?.prop;
9
obj?.method();
10
obj?.prop ?? defaultValue;
11
obj!.prop?.method();
```
#7129 9f4538a Thanks @drwpow! - Removed option, combobox, listbox roles from useSemanticElements suggestions
#7106 236deaa Thanks @arendjr! - Fixed #6985: Inference of return types no longer mistakenly picks up return types of nested functions.
#7102 d3118c6 Thanks @omasakun! - Fixed #7101: noUnusedPrivateClassMembers now handles members declared as part of constructor arguments:
1. If a class member defined in a constructor argument is only used within the constructor, it removes the private modifier and makes it a plain method argument.
2. If it is not used at all, it will prefix it with an underscore, similar to noUnusedFunctionParameter.
#7104 5395297 Thanks @harxki! - Reverting to prevent regressions around ref handling
#7143 1a6933a Thanks @siketyan! - Fixed #6799: The noImportCycles rule now ignores type-only imports if the new ignoreTypes option is enabled (enabled by default).
[!WARNING] Breaking Change: The noImportCycles rule no longer detects import cycles that include one or more type-only imports by default. To keep the old behaviour, you can turn off the ignoreTypes option explicitly:
```
1
{
2
  "linter": {
3
    "rules": {
4
      "nursery": {
5
        "noImportCycles": {
6
          "options": {
7
            "ignoreTypes": false
8
          }
9
        }
10
      }
11
    }
12
  }
13
}
```
#7099 6cc84cb Thanks @arendjr! - Fixed #7062: Biome now correctly considers extended configs when determining the mode for the scanner.
#6887 0cc38f5 Thanks @ptkagori! - Added the useQwikClasslist rule to Biome.

This rule is intended for use in Qwik applications to encourage the use of the built-in class prop (which accepts a string, object, or array) instead of the classnames utility library.

Invalid:
```
1
<div class={classnames({ active: true, disabled: false })} />
```
Valid:
```
1
<div classlist={{ active: true, disabled: false }} />
```
#7019 57c15e6 Thanks @fireairforce! - Added support in the JS parser for import source(a stage3 proposal). The syntax looks like:
```
1
import source foo from "<specifier>";
```
#7053 655049e Thanks @jakeleventhal! - Added the useConsistentTypeDefinitions rule.

This rule enforces consistent usage of either interface or type for object type definitions in TypeScript.

The rule accepts an option to specify the preferred style:
- interface (default): Prefer using interface for object type definitions
- type: Prefer using type for object type definitions
Examples:
```
1
// With default option (interface)
2
// ❌ Invalid
3
type Point = { x: number; y: number };
4

5
// ✅ Valid
6
interface Point {
7
  x: number;
8
  y: number;
9
}
10

11
// With option { style: "type" }
12
// ❌ Invalid
13
interface Point {
14
  x: number;
15
  y: number;
16
}
17

18
// ✅ Valid
19
type Point = { x: number; y: number };
```
The rule will automatically fix simple cases where conversion is straightforward.

2.1.3

Patch Changes

#7057 634a667 Thanks @mdevils! - Added the rule noVueReservedKeys, which prevents the use of reserved Vue keys.

It prevents the use of Vue reserved keys such as those starting with like $el, $data, $props) and keys starting with \_ in data properties, which can cause conflicts and unexpected behavior in Vue components.

Invalid example

1
<script>
2
export default {
3
  data: {
4
    $el: "",
5
    _foo: "bar",
6
  },
7
};
8
</script>

1
<script>
2
export default {
3
  computed: {
4
    $data() {
5
      return this.someData;
6
    },
7
  },
8
};
9
</script>

Valid examples

1
<script>
2
export default {
3
  data() {
4
    return {
5
      message: "Hello Vue!",
6
      count: 0,
7
    };
8
  },
9
};
10
</script>

1
<script>
2
export default {
3
  computed: {
4
    displayMessage() {
5
      return this.message;
6
    },
7
  },
8
};
9
</script>

#6941 734d708 Thanks @JamBalaya56562! - Added @eslint-react/no-nested-component-definitions as a rule source for noNestedComponentDefinitions. Now it will get picked up by biome migrate --eslint.
#6463 0a16d54 Thanks @JamBalaya56562! - Fixed a website link for the useComponentExportOnlyModules linter rule to point to the correct URL.
#6944 e53f2fe Thanks @sterliakov! - Fixed #6910: Biome now ignores type casts and assertions when evaluating numbers for noMagicNumbers rule.
#6991 476cd55 Thanks @denbezrukov! - Fixed #6973: Add support for parsing the :active-view-transition-type() pseudo-class
```
1
:active-view-transition-type(first second) {
2
}
```
#6992 0b1e194 Thanks @ematipico! - Added a new JSON rule called noQuickfixBiome, which disallow the use of code action quickfix.biome inside code editor settings.
#6943 249306d Thanks @JamBalaya56562! - Fixed @vitest/eslint-plugin source url.
#6947 4c7ed0f Thanks @JamBalaya56562! - Fixed ESLint migration for the rule prefer-for from eslint-plugin-solid to Biome’s useForComponent.
#6976 72ebadc Thanks @siketyan! - Fixed #6692: The rules noUnusedVariables and noUnusedFunctionParameters no longer cause an infinite loop when the suggested name is not applicable (e.g. the suggested name is already declared in the scope).
#6990 333f5d0 Thanks @rvanlaarhoven! - Fixed the documentation URL for lint/correctness/noUnknownPseudoClass
#7000 4021165 Thanks @harxki! - Fixed #6795: noUnassignedVariables now correctly recognizes variables used in JSX ref attributes.
#7044 b091ddf Thanks @ematipico! - Fixed #6622, now the rule useSemanticElements works for JSX self-closing elements too.
#7014 c4864e8 Thanks @siketyan! - Fixed #6516: The biome migrate command no longer break the member list with trailing comments.

#6979 29cb6da Thanks @unvalley! - Fixed #6767: useSortedClasses now correctly removes leading and trailing whitespace in className.

Previously, trailing spaces in className were not fully removed.

1
// Think we have this code:
2
<div className="text-sm font-bold            " />
3

4
// Before: applied fix, but a trailing space was preserved
5
<div className="font-bold text-sm " />
6

7
// After: applied fix, trailing spaces removed
8
<div className="font-bold text-sm" />

#7055 ee4828d Thanks @dyc3! - Added the nursery rule useReactFunctionComponents. This rule enforces the preference to use function components instead of class components.

Valid:
```
1
function Foo() {
2
  return <div>Hello, world!</div>;
3
}
```
Invalid:
```
1
class Foo extends React.Component {
2
  render() {
3
    return <div>Hello, world!</div>;
4
  }
5
}
```
#6924 2d21be9 Thanks @ematipico! - Fixed #113, where the Biome Language Server didn’t correctly update the diagnostics when the configuration file is modified in the editor. Now the diagnostics are correctly updated every time the configuration file is modified and saved.
#6931 e6b2380 Thanks @arendjr! - Fixed #6915: useHookAtTopLevel no longer hangs when rules call themselves recursively.
#7012 01c0ab4 Thanks @siketyan! - Fixed #5837: Invalid suppression comments such as biome-ignore-all-start or biome-ignore-all-end no longer causes a panic.
#6949 48462f8 Thanks @fireairforce! - Support parse import defer(which is a stage3 proposal). The syntax look like this:
```
1
import defer * as foo from "<specifier>";
```

#6938 5feb5a6 Thanks @vladimir-ivanov! - Fixed #6919 and #6920: useReadonlyClassProperties now does checks for mutations in async class methods.

Example:

1
class Counter3 {
2
  private counter: number;
3
  async count() {
4
    this.counter = 1;
5
    const counterString = `${this.counter++}`;
6
  }
7
}

#6942 cfda528 Thanks @sterliakov! - Fixed #6939. Biome now understands this binding in classes outside of methods.

2.1.2

Patch Changes

#6865 b35bf64 Thanks @denbezrukov! - Fix #6485: Handle multiple semicolons correctly in blocks (#6485)
```
1
div {
2
  box-sizing: border-box;
3
  color: red;
4
}
```
#6798 3579ffa Thanks @dyc3! - Fixed #6762, Biome now knows that ~/.config/zed/settings.json and ~/.config/Code/User/settings.json allows comments by default.
#6839 4cd62d8 Thanks @ematipico! - Fixed #6838, where the Biome File Watcher incorrectly watched and stored ignored files, causing possible memory leaks when those files were dynamically created (e.g. built files).
#6879 0059cd9 Thanks @denbezrukov! - Refactor: remove one level of indirection for CSS declarations with semicolon Previously, accessing a declaration from a list required an extra step:
```
1
item
2
.as_any_css_declaration_with_semicolon()
3
.as_css_declaration_with_semicolon()
```
Now, it can be done directly with:
```
1
item.as_css_declaration_with_semicolon()
```
#6839 4cd62d8 Thanks @ematipico! - Fixed a bug where the Biome Language Server didn’t correctly ignore specific files when vcs.useIgnoreFile is set to true.
#6884 5ff50f8 Thanks @arendjr! - Improved the performance of noImportCycles by ~30%.
#6903 241dd9e Thanks @arendjr! - Fixed #6829: Fixed a false positive reported by useImportExtensions when importing a .js file that had a matching .d.ts file in the same folder.
#6846 446112e Thanks @darricheng! - Fixed an issue where biome was using the wrong string quotes when the classes string has quotes, resulting in invalid code after applying the fix.
#6823 eebc48e Thanks @arendjr! - Improved #6172: Optimised the way function arguments are stored in Biome’s type inference. This led to about 10% performance improvement in RedisCommander.d.ts and about 2% on @next/font type definitions.
#6878 3402976 Thanks @ematipico! - Fixed a bug where the Biome Language Server would apply an unsafe fix when using the code action quickfix.biome.

Now Biome no longer applies an unsafe code fix when using the code action quickfix.biome.

#6794 4d5fc0e Thanks @vladimir-ivanov! - Fixed #6719: The noInvalidUseBeforeDeclaration rule covers additional use cases.

Examples:

1
type Bar = { [BAR]: true };
2
const BAR = "bar";

1
interface Bar {
2
  child: { grandChild: { [BAR]: typeof BAR; enumFoo: EnumFoo } };
3
}
4
const BAR = "bar";
5
enum EnumFoo {
6
  BAR = "bar",
7
}

#6863 531e97e Thanks @dyc3! - Biome now considers whether the linter is enabled when figuring out how the project should be scanned. Resolves #6815.
#6832 bdbc2b1 Thanks @togami2864! - Fixed #6165: Fixed false negative in noUnusedPrivateClassMembers rule when checking member usage in classes
#6839 4cd62d8 Thanks @ematipico! - Fixed a bug where the root ignore file wasn’t correctly loaded during the scanning phase, causing false positives and incorrect expectations among users.

Now, when using vcs.useIgnoreFile, the **the globs specified in the ignore file from the project root ** will have the same semantics as the files.includes setting of the root configuration.

Refer to the relative web page to understand how they work.
#6898 5beb024 Thanks @arendjr! - Fixed #6891: Improved type inference for array indices.

Example:
```
1
const numbers: number[];
2
numbers[42]; // This now infers to `number | undefined`.
```

#6809 8192451 Thanks @arendjr! - Fixed #6796: Fixed a false positive that happened in noFloatingPromises when calling functions that were declared as part of for ... of syntax inside async functions.

Instead, the variables declared inside for ... of loops are now correctly inferred if the expression being iterated evaluates to an Array (support for other iterables will follow later).

Invalid example

1
const txStatements: Array<(tx) => Promise<any>> = [];
2

3
db.transaction((tx: any) => {
4
  for (const stmt of txStatements) {
5
    // We correctly flag this resolves to a `Promise`:
6
    stmt(tx);
7
  }
8
});

Valid example

1
async function valid(db) {
2
  const txStatements: Array<(tx: any) => void> = [(tx) => tx.insert().run()];
3

4
  db.transaction((tx: any) => {
5
    for (const stmt of txStatements) {
6
      // We don't flag a false positive here anymore:
7
      stmt(tx);
8
    }
9
  });
10
}

#6757 13a0818 Thanks @mdevils! - Added the rule noVueReservedProps, resolves #6309.

It prevents the use of reserved Vue prop names such as key and ref which can cause conflicts and unexpected behavior in Vue components.

Invalid example

1
import { defineComponent } from "vue";
2

3
export default defineComponent({
4
  props: ["ref", "key", "foo"],
5
});

1
<script setup>
2
defineProps({
3
  ref: String,
4
  key: String,
5
  foo: String,
6
});
7
</script>

Valid examples

1
import { defineComponent } from "vue";
2

3
export default defineComponent({
4
  props: ["foo"],
5
});

1
<script setup>
2
defineProps({ foo: String });
3
</script>

#6840 1a57b51 Thanks @denbezrukov! - Allow multiple identifiers in ::part() pseudo-element selector.
```
1
::part(first second) {
2
}
```
#6845 4fd44ec Thanks @arendjr! - Fixed #6510: The scanner no longer shows diagnostics on inaccessible files unless --verbose is used.
#6844 b7e2d4d Thanks @sterliakov! - Fixed #6837: Fixed regression with multiple consecutive line suppression comments using instances (like // biome-ignore lint/correctness/useExhaustiveDependencies(depName): reason).
#6818 5f3f5a6 Thanks @siketyan! - Fixed an issue where textDocument/codeAction in the LSP could respond with outdated text edits after the workspace watcher observed outdated changes to the file.
#6804 3e6ab16 Thanks @arendjr! - noFloatingPromises will no longer suggest to add await keyword inside synchronous callbacks nested inside async functions.
#6901 c9e969a Thanks @arendjr! - Fixed #6777: Fixed type inference handling of this to avoid infinite recursion.

Thanks to @sterliakov for the thorough investigation!

#6855 d1581c7 Thanks @vladimir-ivanov! - Fixed #6775: useReadonlyClassProperties now also captures mutations inside function arguments.

Example:

1
class Counter {
2
  private counter: number;
3
  count() {
4
    console.log(this.counter++);
5
    const counterString = `${this.counter++}`;
6
  }
7
}

#6839 4cd62d8 Thanks @ematipico! - Fixed a bug where Biome didn’t throw any error when vcs.useIgnoreFile is set to true, and there wasn’t any ignore file read. Now Biome correctly throws an error if no ignore files are found.
#6911 6d68074 Thanks @arendjr! - Fixed #6838: Reduce resource consumption in the Biome Language Server by using non-recursive filesystem watchers instead of recursive ones.

Watchers are responsible for notifying Biome of changes to files in the filesystem. We used to set up a single recursive watcher, but that meant that Biome would receive filesystem notifications for all files in your project, even for ignored folders such as build/ or dist/ folders.

With this patch, we set up non-recursive watchers only for the folders that are relevant to a project.

Related to this, we also solved an issue where incoming notifications were incorrectly filtered, causing ignored files to be processed and stored in our module graph anyway.

2.1.1

Patch Changes

#6781 9bbd34f Thanks @siketyan! - Fixed the FileFeaturesResult interface in the WASM API was defined as a mapped object but the actual value was a Map object.
#6761 cf3c2ce Thanks @dyc3! - Fixed #6759, a false positive for noFocusedTests that was triggered by calling any function with the name fit on any object.

The following code will now pass the noFocusedTests rule:
```
1
import foo from "foo";
2
foo.fit();
```

2.1.0

Minor Changes

#6512 0c0bf82 Thanks @arendjr! - The rule noFloatingPromises can now detect floating arrays of Promises.

Invalid examples

1
// This gets flagged because the Promises are not handled.
2
[1, 2, 3].map(async (x) => x + 1);

Valid examples

1
await Promise.all([1, 2, 3].map(async (x) => x + 1));

#6637 6918085 Thanks @arendjr! - Type inference is now able to handle the sequence operator ( ,), as well as post- and pre-update operators: ++.

Example

1
let x = 5;
2

3
// We now infer that `x++` resolves to a number, while the expression as a whole
4
// becomes a Promise:
5
(x++, new Promise((resolve) => resolve("comma")));

#6752 c9eaca4 Thanks @arendjr! - Fixed #6646: .gitignore files are now picked up even when running Biome from a nested directory, or when the ignore file itself is ignored through files.includes.
#6746 90aeead Thanks @arendjr! - biome migrate no longer enables style rules that were recommended in v1, because that would be undesirable for users upgrading from 2.0.

Users who are upgrading from Biome 1.x are therefore advised to first upgrade to Biome 2.0, and run the migration, before continuing to Biome 2.1 or later.

#6583 d415a3f Thanks @arendjr! - Added the nursery rule noMisusedPromises.

It signals Promises in places where conditionals or iterables are expected.

Invalid examples

1
const promise = Promise.resolve("value");
2

3
// Using a `Promise` as conditional is always truthy:
4
if (promise) {
5
  /* ... */
6
}
7

8
// Spreading a `Promise` has no effect:
9
console.log({ foo: 42, ...promise });
10

11
// This does not `await` the `Promise`s from the callbacks,
12
// so it does not behave as you may expect:
13
[1, 2, 3].forEach(async (value) => {
14
  await fetch(`/${value}`);
15
});

Valid examples

1
const promise = Promise.resolve("value");
2

3
if (await promise) {
4
  /* ... */
5
}
6

7
console.log({ foo: 42, ...(await promise) });

#6405 cd4a9bb Thanks @vladimir-ivanov! - Added the ignoreRestSiblings option to the noUnusedFunctionParameters rule.

This option is used to ignore unused function parameters that are siblings of the rest parameter.

The default is false, which means that unused function parameters that are siblings of the rest parameter will be reported.

Example
```
1
{
2
  "rules": {
3
    "noUnusedFunctionParameters": ["error", { "ignoreRestSiblings": true }]
4
  }
5
}
```
#6614 0840021 Thanks @arendjr! - We have implemented a more targeted version of the scanner, which ensures that if you provide file paths to handle on the CLI, the scanner will exclude directories that are not relevant to those paths.

Note that for many commands, such as biome check and biome format, the file paths to handle are implicitly set to the current working directory if you do not provide any path explicitly. The targeted scanner also works with such implicit paths, which means that if you run Biome from a subfolder, other folders that are part of the project are automatically exempted.

Use cases where you invoke Biome from the root of the project without providing a path, as well as those where project rules are enabled, are not expected to see performance benefits from this.

Implemented #6234, and fixed #6483 and #6563.
#6488 c5ee385 Thanks @ianzone! - nx.json and project.json have been added to the list of well-known files.
#6720 52e36ae Thanks @minht11! - Added $ symbol to organizeImports :ALIAS: group.

import { action } from '$lib' will be treated as alias import.

Patch Changes

#6712 2649ac6 Thanks @sterliakov! - Fixed #6595: Biome now supports // biome-ignore-all file-level suppressions in files that start with a shebang (#!).
#6758 28dc49e Thanks @arendjr! - Fixed #6573: Grit plugins can now match bare imports.

Example

The following snippet:
```
1
`import $source`
```
will now match:
```
1
import "main.css";
```

#6550 b424f46 Thanks @arendjr! - Type inference is now able to handle logical expressions: &&, ||, and ??.

Examples

1
// We can now infer that because `true` is truthy, the entire expression
2
// evaluates to a `Promise`.
3
true && Promise.reject("logical operator bypass");
4

5
// And we know that this doesn't:
6
false && Promise.reject("logical operator bypass");
7

8
// Truthiness, falsiness, and non-nullishness can all be determined on more
9
// complex expressions as well. So the following also works:
10
type Nullish = null | undefined;
11

12
type Params = {
13
  booleanOption: boolean | Nullish;
14
  falsyOption: false | Nullish;
15
};
16

17
function foo({ booleanOption, falsyOption }: Params) {
18
  // This may be a Promise:
19
  booleanOption ?? Promise.reject("logical operator bypass");
20

21
  // But this never is:
22
  falsyOption && Promise.reject("logical operator bypass");
23
}

#6413 4aa0e50 Thanks @wojtekmaj! - Improved error message in useDateNow rule.
#6673 341e062 Thanks @dyc3! - Fixed a case where the HTML formatter would mangle embedded language tags if whitespaceSensitivity was set to strict
#6642 a991229 Thanks @unvalley! - Fixed #4494: The noSecrets rule now correctly uses the entropyThreshold option to detect secret like strings.
#6520 0c43545 Thanks @arendjr! - Type inference is now able to handle ternary conditions in type aliases.

Note that we don’t attempt to evaluate the condition itself. The resulting type is simply a union of both conditional outcomes.

Example
```
1
type MaybeResult<T> = T extends Function ? Promise<string> : undefined;
2

3
// We can now detect this function _might_ return a `Promise`:
4
function doStuff<T>(input: T): MaybeResult<T> {
5
  /* ... */
6
}
```
#6711 1937691 Thanks @sterliakov! - Fixed #6654: Fixed range highlighting of <explanation> placeholder in inline suppression block comments.
#6756 d12b26f Thanks @dyc3! - Fixed #6669: Added an exception to noUnusedImports to allow type augmentation imports.
```
1
import type {} from "@mui/lab/themeAugmentation";
```
#6643 df15ad6 Thanks @skewb1k!
Fixed #4994: LSP server registered some capabilities even when the client did not support dynamic registration.
#6599 5e611fa Thanks @vladimir-ivanov! - Fixed #6380: The noFocusedTests rule now correctly displays the function name in the diagnostic message when a test is focused.

Every instance of a focused test function (like fdescribe, fit, ftest and only) had the word ‘only’ hardcoded. This has been updated to use the actual function name, so the message is now more accurate and specific.

Example for fdescribe:
```
1
  i The 'fdescribe' method is often used for debugging or during implementation.
2

3
  i Consider removing 'f' prefix from 'fdescribe' to ensure all tests are executed.
```

#6671 0c9ab43 Thanks @vladimir-ivanov! - Fixed #6634: The useReadonlyClassProperties rule now correctly flags mutations in class getters and in arrow functions within class properties.

Examples:

1
class GetterWithMutationValue {
2
  #value: string;
3

4
  get value() {
5
    if (!this.#value) {
6
      this.#value = "defaultValue";
7
    }
8

9
    return this.#value;
10
  }
11
}

1
class ClassPropertyArrowFunctionWithMutation {
2
  private bar: string | null = null;
3

4
  readonly action = () => {
5
    this.bar = "init";
6
  };
7
}

#6682 ca04cea Thanks @ematipico! - Fixed #6668: Biome Assist is now enabled by default for CSS files.

#6525 66b089c Thanks @arendjr! - Type inference can now infer the return types of functions and methods without annotations.

Examples

1
const sneakyObject = {
2
  doSomething() {
3
    return Promise.resolve("This is a floating promise!");
4
  },
5
};
6

7
// We can now detect that `doSomething()` returns a `Promise`.
8
sneakyObject.doSomething();

#6531 c06df79 Thanks @arendjr! - Biome’s type inference now detects the type of properties with getters.

Examples

1
const sneakyObject2 = {
2
  get something() {
3
    return new Promise((_, reject) => reject("This is a floating promise!"));
4
  },
5
};
6
// We now detect this is a Promise:
7
sneakyObject2.something;

#6587 a330fcc Thanks @Conaclos! - organizeImports is now able to sort named specifiers and import attributes with bogus nodes.
#6618 6174869 Thanks @Shinyaigeek! - Fixed #6610: JSON import attributes are now correctly detected when they contain extra whitespace.
#6753 fce5d2c Thanks @dyc3! - Improved the error messages when Biome is provided incompatible arguments on the CLI.
#6587 a330fcc Thanks @Conaclos! - Fixed #6491: The action of useSortedKeys removed comments or wrongly transferred them to distinct nodes.
#6696 92964a7 Thanks @unvalley! - Fixed #6633: The noImplicitCoercion rule no longer reports diagnostics for 1 / value expressions.
```
1
1 / value; // no error
```
#6683 43d871e Thanks @ematipico! - Fixed #6537: Biome no longer removes the trailing comma from JSON files when formatter.json.trailingCommas is explicitly set to "all".
#6693 bfdce0b Thanks @dyc3! - Fixed #6691: The HTML parser will now consider . to be a valid character for tag names.
#6716 ead03d1 Thanks @siketyan! - The Biome LSP server no longer responds with an error for a textDocument/codeActions request when Biome doesn’t support a feature for the file (e.g. Code actions aren’t supported in GritQL files).
#6679 7bf9a60 Thanks @marko-hologram! - Fixed #6638: JavaScript formatter overrides options now correctly override expand option. JSON formatter overrides options now correctly override bracketSpacing and expand options.
#6717 7f5b541 Thanks @siketyan! - Fixed #6688: the noUselessFragments no longer reports <Fragment /> elements that includes HTML character entities.
#6600 853e1b5 Thanks @daivinhtran! - Fixed #4677: The noUnusedImports rule won’t produce diagnostics for types used in comments of static members anymore.
#6662 3afc804 Thanks @arendjr! - If a nested configuration file is ignored by the root configuration, it will now actually be ignored.

Biome has an exception in place for configuration files so they cannot be ignored, because the configuration files are vital to Biome itself. But this exception was incorrectly applied to nested configurations as well. Now only the root configuration is exempt from being ignored.
#6596 c0718ca Thanks @ematipico! - Fixed #6566: Biome no longer errors when using the option --files-ignore-unknown=true in stdin mode.

Biome has also become less strict when using --stdin-file-path in stdin mode. It will no longer error if the file path doesn’t contain an extension, but instead it will return the original content.
#6562 153eda7 Thanks @vladimir-ivanov! - Added the nursery rule noMagicNumbers. The rule detects and reports the use of “magic numbers” — numeric literals that are used directly in code without being assigned to a named constant.

Example
```
1
let total = price * 1.23; // Magic number for tax rate will highlight 1.23 as magic number
```
#6663 af78d6d Thanks @ematipico! - Fixed #6656: Biome now correctly formats HTML void elements such as <meta> when they contain a self-closing slash.
```
1
<meta foo="bar" />
2
<meta foo="bar">
```
#6732 31e4396 Thanks @vladimir-ivanov! - Resolved #6281: Improved performance of handling package.json files in the scanner.
#6625 19cb475 Thanks @arendjr! - Fixed #6616: Fixed an issue with extending configurations that contained an explicit root field while the configuration in the project did not.
#6650 19aab18 Thanks @sterliakov! - Fixed #6621: Improved handling of multiple adjacent line suppressions. Biome now handles such suppressions separately, tracking whether each one is used.
#6700 cdd6e17 Thanks @denbezrukov! - Fixed #6680: Biome incorrectly formatted container-style queries by inserting misplaced spaces.
```
1
@container style (--responsive: true) {}
2
@container style(--responsive: true) {}
```
#6709 ecf3954 Thanks @dyc3! - Fixed #6038: Fixed a false positive in noShadow where a function parameter in a type definition was erroneously flagged as a violation.

#6593 a4acbb7 Thanks @arendjr! - Type inference is now able to handle ternary conditions in expressions.

Examples

1
const condition = Math.random() > -1; // Always true, but dynamic to linter
2

3
// We now detect that this may return a `Promise`.
4
condition ? Promise.reject("ternary bypass") : null;
5

6
// On the other hand, we know the following is never a `Promise`:
7
const alwaysFalsy = 0;
8
alwaysFalsy ? Promise.reject("ternary bypass") : null;

#6428 4b501d3 Thanks @siketyan! - Added MemoryFileSystem to the WASM API.

You can now insert a file from your JS code:

1
import { MemoryFileSystem, Workspace } from "@biomejs/wasm-web";
2

3
const fs = new MemoryFileSystem();
4
const workspace = Workspace.withFileSystem(fs);
5

6
fs.insert("/index.js", new TextEncoder().encode("let foo = 1;"));
7
fs.remove("/index.js");

#6594 626d4a1 Thanks @ematipico! - Fixed #6528: Biome didn’t return the correct output when applying source.fixAll.biome inside Astro/Vue/Svelte files that contained safe fixed.

2.0.6

Patch Changes

#6557 fd68458 Thanks @ematipico! - Fixed a bug where Biome didn’t provide all the available code actions when requested by the editor.
#6511 72623fa Thanks @Conaclos! - Fixed #6492. The organizeImports assist action no longer duplicates a comment at the start of the file when :BLANK_LINE: precedes the first import group.
#6557 fd68458 Thanks @ematipico! - Fixed #6287 where Biome Language Server didn’t adhere to the settings.requireConfiguration option when pulling diagnostics and code actions. Note that for this configuration be correctly applied, your editor must support dynamic registration capabilities.
#6551 0b63b1d Thanks @Conaclos! - Fixed #6536. useSortedKeys no longer panics in some edge cases where object spreads are involved.
#6503 9a8fe0f Thanks @ematipico! - Fixed #6482 where nursery rules that belonged to a domain were incorrectly enabled.
#6565 e85761c Thanks @daivinhtran! - Fixed #4677: Now the noUnusedImports rule won’t produce diagnostics for types used in JSDoc comment of exports.
#6166 b8cbd83 Thanks @mehm8128! - Added the nursery rule noExcessiveLinesPerFunction. This rule restrict a maximum number of lines of code in a function body.

The following code is now reported as invalid when the limit of maximum lines is set to 2:
```
1
function foo() {
2
  const x = 0;
3
  const y = 1;
4
  const z = 2;
5
}
```
The following code is now reported as valid when the limit of maximum lines is set to 3:
```
1
const bar = () => {
2
  const x = 0;
3
  const z = 2;
4
};
```
#6553 5f42630 Thanks @denbezrukov! - Fixed #6547. Now the Biome CSS parser correctly parses @starting-style when it’s used inside other at-rules. The following example doesn’t raise an error anymore:
```
1
@layer my-demo-layer {
2
  @starting-style {
3
    div.showing {
4
      background-color: red;
5
    }
6
  }
7
}
```
#6458 05402e3 Thanks @ematipico! - Fixed an issue where the rule useSemanticElements used the incorrect range when positioning suppression comments.
#6560 6d8a6b9 Thanks @siketyan! - Fixed #6559: the error message on detected a large file was outdated and referred a removed configuration option files.ignore.
#6458 05402e3 Thanks @ematipico! - Fixed #6384. The rule useAltText now emits a diagnostic with a correct range, so suppression comments can work correctly.
#6518 7a56288 Thanks @wojtekmaj! - Fixed #6508, where the rule noUselessFragments incorrectly flagged Fragments containing HTML entities as unnecessary.
#6517 c5217cf Thanks @arendjr! - Fixed #6515. When using the extends field to extend a configuration from an NPM package, we now accept the condition names "biome" and "default" for exporting the configuration in the package.json.

This means that where previously your package.json had to contain an export declaration similar to this:
```
1
{
2
  "exports": {
3
    ".": "./biome.json"
4
  }
5
}
```
You may now use one of these as well:
```
1
{
2
  "exports": {
3
    ".": {
4
      "biome": "./biome.json"
5
    }
6
  }
7
}
```
Or:
```
1
{
2
  "exports": {
3
    ".": {
4
      "default": "./biome.json"
5
    }
6
  }
7
}
```
#6219 a3a3715 Thanks @huangtiandi1999! - Added new nursery rule noUnassignedVariables, which disallows let or var variables that are read but never assigned.

The following code is now reported as invalid:
```
1
let x;
2
if (x) {
3
  console.log(1);
4
}
```
The following code is now reported as valid:
```
1
let x = 1;
2
if (x) {
3
  console.log(1);
4
}
```
#6395 f62e748 Thanks @mdevils! - Added the new nursery rule noImplicitCoercion, which disallows shorthand type conversions in favor of explicit type conversion functions.

Example (Invalid): Boolean conversion using double negation:
```
1
!!foo;
2
!!(foo + bar);
```
Example (Invalid): Number conversion using unary operators:
```
1
+foo;
2
-(-foo);
3
foo - 0;
4
foo * 1;
5
foo / 1;
```
Example (Invalid): String conversion using concatenation:
```
1
"" + foo;
2
foo + "";
3
`` + foo;
4
foo += "";
```
Example (Invalid): Index checking using bitwise NOT:
```
1
~foo.indexOf(1);
2
~foo.bar.indexOf(2);
```
Example (Valid): Using explicit type conversion functions:
```
1
Boolean(foo);
2
Number(foo);
3
String(foo);
4
foo.indexOf(1) !== -1;
```
#6544 f28b075 Thanks @daivinhtran! - Fixed #6536. Now the rule noUselessFragments produces diagnostics for a top-level useless fragment that is in a return statement.
#6320 5705f1a Thanks @mdevils! - Added the new nursery rule useUnifiedTypeSignature, which disallows overload signatures that can be unified into a single signature.

Overload signatures that can be merged into a single signature are redundant and should be avoided. This rule helps simplify function signatures by combining overloads by making parameters optional and/or using type unions.

Example (Invalid): Overload signatures that can be unified:
```
1
function f(a: number): void;
2
function f(a: string): void;
```
```
1
interface I {
2
  a(): void;
3
  a(x: number): void;
4
}
```
Example (Valid): Unified signatures:
```
1
function f(a: number | string): void {}
```
```
1
interface I {
2
  a(x?: number): void;
3
}
```
Example (Valid): Different return types cannot be merged:
```
1
interface I {
2
  f(): void;
3
  f(x: number): number;
4
}
```
#6545 2782175 Thanks @ematipico! - Fixed #6529, where the Biome Language Server would emit an error when the user would open a file that isn’t part of its workspace ( node_modules or external files). Now the language server doesn’t emit any errors and it exits gracefully.

#6524 a27b825 Thanks @vladimir-ivanov! - Fixed #6500: The useReadonlyClassProperties rule now correctly marks class properties as readonly when they are assigned in a constructor, setter or method, even if the assignment occurs inside an if or else block.

The following code is now correctly detected by the rule:

1
class Price {
2
  #price: string;
3

4
  @Input()
5
  set some(value: string | number) {
6
    if (
7
      value === undefined ||
8
      value === null ||
9
      value === "undefined" ||
10
      value === "null" ||
11
      Number.isNaN(value)
12
    ) {
13
      this.#price = "";
14
    } else {
15
      this.#price = "" + value;
16
    }
17
  }
18
}

#6355 e128ea9 Thanks @anthonyshew! - Added a new nursery rule noAlert that disallows the use of alert, confirm and prompt.

The following code is deemed incorrect:
```
1
alert("here!");
```
#6548 37e9799 Thanks @ematipico! - Fixed #6459, where the Biome LSP was not taking into account the correct settings when applying source.fixAll.biome code action.

Version History

2.2.4 Latest

Patch Changes

Example

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Invalid

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CSS

GraphQL

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