Version History

2.5.14 Latest

Patch Changes

#9022 0d49e24 Thanks @dyc3! - Added the nursery rule noReturnInFinally. This rule disallows return statements in Promise.prototype.finally() callbacks, including inside nested blocks and conditional branches. Returns in nested functions are ignored by the rule.
```
1
// Invalid: return in finally callback
2
Promise.resolve(1).finally(() => { return 2 })
3

4
// Valid: no return in finally callback
5
Promise.resolve(1).finally(() => { console.log(2) })
```
Returning a value from a Promise.prototype.finally() callback does not replace the original promise’s fulfillment value, which can be confusing. Returned promises and thenables are awaited, and their rejection rejects the resulting promise.
#11754 71eaa0d Thanks @griff-rees! - Added the nursery rule noSvelteAtDebugTags, which disallows Svelte’s {@debug} tag.
```
1

2
{@debug user}
```
The {@debug} tag is a debugging aid and should be removed once you no longer need it, as it should not remain in production code. The rule provides a safe fix that removes the tag.
#11725 5eb5f09 Thanks @m1handr! - Added the nursery rule useValidTestTitle, which enforces valid titles for unit test cases and suites.
#11735 9bd70c7 Thanks @ematipico! - Fixed #8471: source.fixAll.biome ignored formatter.formatWithErrors. It now applies safe fixes without formatting files that have parse errors when the option is disabled.
#11715 f05a3c3 Thanks @ematipico! - Fixed #7771: Grit plugins that use sequential no longer panic when Biome processes files.
#11766 c2542c6 Thanks @dyc3! - Fixed validation of readonly and accessor modifiers: combining them in either order now reports that they cannot be used together.
#11461 22e9966 Thanks @FoundDream! - Fixed #11423: Multiline template interpolations now preserve the indentation of their closing brace when the source indentation is not a multiple of tabWidth.
```
1
const value = `
2
     ${
3
       condition
4
         ? "yes"
5
         : "no"
6
}
7
     }
8
`;
```
#11766 c2542c6 Thanks @dyc3! - Fixed #11763: TypeScript class members using override accessor, such as override accessor value = 1, now parse correctly. The reversed order, accessor override, now reports that override must precede accessor.
#11790 17d0ff0 Thanks @ematipico! - Fixed #10248: noUselessFragments now allows fragments with props in Astro files, such as <Fragment slot="name">{text}</Fragment> inside template expressions.
#11777 7ee3a6c Thanks @ematipico! - Fixed #7573: added the requireExplicitCase option to useExhaustiveSwitchCases. When set to true, the rule reports missing cases even when the switch has a default clause, so you can keep a runtime fallback while checking that every value in the union has its own case. The option defaults to false.
#11751 d37f24b Thanks @ematipico! - Fixed #8347: the fix from useConsistentArrowReturn now parenthesizes returned expressions that begin with object literals before removing the arrow function body braces, preventing invalid output for expressions such as object property access.
#11784 46e8912 Thanks @dyc3! - Fixed #11782: noUndeclaredCustomProperties could hang while checking stylesheets imported by JavaScript modules with many shared dependencies.
#11731 1534885 Thanks @ematipico! - Fixed #7984: The fix from useSimplifiedLogicExpression now preserves line breaks in multiline conditions with line comments, preventing the right-hand side condition from being commented out.
#11735 9bd70c7 Thanks @ematipico! - Fixed #7304: the HTML formatter now preserves authored segment breaks between CJK characters, and next to CJK punctuation, instead of replacing them with spaces.
```
1
<div lang="zh-Hant-TW">
2
  這個段落是那麼長， 在一行寫不行。
3
  這個段落是那麼長，
4
  在一行寫不行。
5
</div>
```
#11749 ff992a1 Thanks @ematipico! - Fixed #11747: formatting and checking large parenthesized object expressions no longer exhibit quadratic slowdowns.
#11736 1dd1fc4 Thanks @dyc3! - Fixed #8177: code actions no longer modify the wrong part of Vue, Svelte, or Astro files when experimental full HTML support is disabled.
#11743 3835945 Thanks @santichausis! - Fixed #10247: biome check --write/biome lint --write now correctly writes fixes for code inside an HTML attribute expression (for example a Svelte onclick={...} handler, or a mustache expression like {count}), instead of silently reporting the diagnostic as fixable and applying nothing.

For example, running biome lint --write --unsafe for useBlockStatements (an unsafe fix) on this Svelte component used to leave the file unchanged:
```
1
<button onclick={() => { if (open) close(); }}>Close</button>
```
#11740 8ea8b4a Thanks @dyc3! - Fixed #11453: useConsistentTestIt now updates imports alongside calls, preserving the original export through an alias. The rule ignores locally declared functions and withholds fixes when the preferred name would conflict with another binding or global reference.
#11355 27177ca Thanks @dyc3! - Fixed the HTML formatter incorrectly applying native HTML element formatting to PascalCase component names such as <Ul> and <Body> in Vue, Svelte, and Astro files.
```
1
<Body>
2
  <div>content</div>
3
</Body>
4
<Body><div>content</div></Body>
```
#11355 27177ca Thanks @dyc3! - Fixed the HTML formatter incorrectly applying SVG block formatting to unknown elements whose names matched SVG element names.
```
1
<foreignobject>
2
  <div>content</div>
3
</foreignobject>
4
<foreignobject><div>content</div></foreignobject>
```
#11741 fc69047 Thanks @dyc3! - Fixed #8893: useImportExtensions no longer suggests adding .ts to .jsx imports when a colocated .d.ts file provides type declarations.
#11642 c87341c Thanks @dyc3! - Added the nursery rule useConsistentFunctionStyle, which requires a consistent style for defining functions.

By default, the rule reports the following declaration because it requires a function expression assigned to a variable:
```
1
function greet() {
2
    return "Hello";
3
}
```
#11770 ddfd622 Thanks @dyc3! - Fixed #8980: suppression comments targeting the entire assist category are now respected, including biome-ignore-all assist when running check.
#11792 7a4b895 Thanks @dyc3! - Fixed dashed utility base names in the Tailwind parser, including border-bs, font-features, and scrollbar-thumb. Classes such as min-inline-[12rem] now preserve the complete base name and parse the arbitrary value separately.
#11739 1fc17e3 Thanks @Netail! - The rule useIncludes now also reports lastIndexOf() comparisons and some() calls with a strict-equality callback.
```
1
arr.lastIndexOf(x) !== -1
2

3
arr.some(item => item === x)
```
#11735 9bd70c7 Thanks @ematipico! - Fixed #6888. GritQL plugins can now use contains on import-clause metavariables such as $clause in import $clause from "module" patterns.
#11790 17d0ff0 Thanks @ematipico! - Fixed #11786: useAnchorContent now reports anchors without accessible content in HTML, Astro, Vue, and Svelte even when they have an aria-label, aria-labelledby, or title attribute, matching JSX behavior.
#11651 a9c4aa0 Thanks @saberoueslati! - Added the new nursery rule noVueUndeclaredDirectives, which reports custom Vue directives that are not declared by a <script setup> binding, the component’s directives option, or the rule’s globals option. Closes #11478.
```
1
<template>
2
  
3
  <div v-highlight></div>
4
</template>
```
Aliased named imports in single-file components are now tracked under their local name, so noUndeclaredVariables recognizes vHighlight in import { highlight as vHighlight } from "./directives".
#11715 f05a3c3 Thanks @ematipico! - Fixed #7795. The noJsxLiterals rule now ignores surrounding whitespace when matching literals against allowedStrings.
#11780 99c7049 Thanks @ematipico! - Fixed false positives in useExhaustiveSwitchCases when numeric cases use different spellings of the same value. For example, case 0x1 now covers the numeric literal type 1.
#11720 c7c4e2b Thanks @ematipico! - Fixed #7880: noUselessStringConcat no longer reports literal concatenations split across multiple lines when a numeric literal ends the chain.
#11355 27177ca Thanks @dyc3! - Improved performance of the HTML formatter for documents that contain many HTML-native or SVG-native tags.
#11720 c7c4e2b Thanks @ematipico! - Fixed #7949: useReadonlyClassProperties now reports static class properties that are never reassigned.
#11751 d37f24b Thanks @ematipico! - Fixed #7644: useImportExtensions now resolves path aliases declared by referenced TypeScript project configurations.
#11791 f88793c Thanks @dyc3! - Fixed a false positive in useTailwindShorthandClasses for strings in conditional tests, such as cn(m === "w-2 h-2" ? "bg-red-800" : "bg-red-400").
#11720 c7c4e2b Thanks @ematipico! - Fixed #7783: noNoninteractiveElementInteractions no longer reports event handlers on native <dialog> elements.
#11733 7030068 Thanks @dyc3! - Fixed #11730: useExhaustiveSwitchCases reports missing cases when iterating over a class property with for...of.
#11717 2107dae Thanks @ternaus! - Fixed #11716: the noUnknownAttribute rule now accepts fullscreen event handlers, the credentialless iframe property, and the SVG maskType property when the React dependency range allows React 19.3 or later. The credentialless and maskType properties are restricted to <iframe> and <mask> elements, respectively.
#11737 b7e3559 Thanks @dyc3! - Fixed #11692: noFloatingPromises now detects unhandled promises returned through generic method signatures, including Playwright fixtures.
#11780 99c7049 Thanks @ematipico! - Fixed #7747: useExhaustiveSwitchCases now reports missing cases for literal unions derived from const tuples with (typeof values)[number] and objects with keyof typeof object.

Other type-aware rules, including noFloatingPromises and noUselessTypeConversion, also recognize supported indexed-access results.
#11724 a9a5e9a Thanks @dyc3! - Fixed redundant parentheses around binary and logical unary operands with leading line comments.
```
1
!(
2
  // leading
3
  (a || b)
4
  a || b
5
);
```
#11715 f05a3c3 Thanks @ematipico! - Fixed #7722: noUnusedImports no longer reports type-only imports used in computed names of declared class properties.
#11731 1534885 Thanks @ematipico! - Fixed #6390: Biome now offers suppression actions for noDynamicNamespaceImportAccess in editors.
#11751 d37f24b Thanks @ematipico! - Fixed #7533: noDescendingSpecificity no longer compares selector specificity across separate cascade layer blocks.

#11735 9bd70c7 Thanks @ematipico! - Fixed #6206: useUniqueElementIds no longer reports static IDs on elements in SVG contexts.

1
<svg>
2
    <defs>
3
        <pattern id="dots" width="10" height="10" />
4
    </defs>
5
    <rect fill="url(#dots)" width="100%" height="100%" />
6
</svg>

#11715 f05a3c3 Thanks @ematipico! - Fixed #5447, so the GitHub reporter now associates annotations with the correct files when Biome runs from a nested directory.
#11720 c7c4e2b Thanks @ematipico! - Fixed #7816: useHookAtTopLevel no longer reports methods named like hooks when called on another function’s result, such as Reactotron.configure(...).useReactNative(...).
#11355 27177ca Thanks @dyc3! - Removed special HTML formatter handling for the obsolete <listing> element.
#11731 1534885 Thanks @ematipico! - Fixed an issue where Grit plugin code fixes weren’t available as editor code actions.
#11726 dea163f Thanks @dyc3! - Fixed #11722: the JavaScript formatter inserts a newline before the closing angle bracket when a leading comment forces type arguments onto multiple lines.
```
1
type Foo = Record<
2
  // comment
3
  string,
4
  number>;
5
  number
6
>;
```

#9758 02ea438 Thanks @Netail! - Added the nursery rule noJsonUnsafeValues, which disallows JSON values that are unsafe to use between different tools or languages.

Invalid:

1
[
2
  2e308, // Number evaluating to Infinity
3
  -2e308, // Number evaluating to -Infinity
4
  "\ud83d", // String with lone surrogate
5
  1e-400, // Unsafe zero (too small, will evaluate to 0)
6
  9007199254740992, // Unsafe integer (outside safe integer range)
7
  2.2250738585072009e-308, // Subnormal number
8
]

#11790 17d0ff0 Thanks @ematipico! - Fixed #8574: the JavaScript formatter sometimes added extra parentheses and moved comments when formatting multiline expressions after operators such as !. Comments now stay beside the values they describe, without an extra pair of parentheses.
```
1
!(
2
  (
3
    cond1 || // force this to be multi line
4
    cond3
5
  ) // comment
6
  cond1 || // force this to be multi line
7
  cond3 // comment
8
);
```
#11715 f05a3c3 Thanks @ematipico! - Fixed #7711: biome lint --suppress no longer fails with conflicting rule fixes when multiple diagnostics target a declaration preceded by a multiline comment.
#11700 0e9fe53 Thanks @dyc3! - Added the nursery rule noObsoleteTags, which reports obsolete HTML elements in HTML and JSX, such as <font color="red">Text</font>.
#11735 9bd70c7 Thanks @ematipico! - Fixed #7363: Biome GritQL plugins now match TypeScript interface snippets such as interface $name { $body }.
#11729 f047985 Thanks @m1handr! - Added support for suite() as an alias of describe() across test analysis rules and formatter. Rules now recognize suite, fsuite, xsuite, and test.suite blocks. The formatter recognises them as test declarations.
#11778 4b7aa1f Thanks @ematipico! - Fixed #7727: GritQL snippets such as import $what from $where now match namespace imports, including type-only imports. Explicit import type $what from $where patterns also match type-only named and namespace imports.
#11715 f05a3c3 Thanks @ematipico! - Fixed #7603: useSingleJsDocAsterisk no longer reports asterisks that are part of JSDoc comment content, such as italic text, as extra line markers.
#11706 e19512a Thanks @dyc3! - Fixed #11704: files re-included by negation patterns in a nested .gitignore are processed when vcs.useIgnoreFile is enabled, even when the ignore file contains *.
#11718 76a302a Thanks @dyc3! - Fixed #8573: own-line comments before binary operators stay above the operator when javascript.formatter.operatorLinebreak is "before".
```
1
foo
2
  || // comment
3
  bar;
4
  // comment
5
  || bar;
```
#9797 64fd314 Thanks @Netail! - Added the nursery rule useConsistentObjectKeys, which requires JSON object keys to follow a consistent Unicode representation.

2.5.13

Patch Changes

#11379 07a0073 Thanks @Netail! - Added the nursery rule useLayeredStyles, which enforces that style rules are defined within a cascade layer and import rules to import its styles into a cascade layer.
```
1
/* Invalid */
2
@import 'foo.css';
3

4
.my-style {
5
  color: red;
6
}
7

8
/* Valid */
9
@import 'foo.css' layer(base);
10

11
@layer base {
12
  .my-style {
13
    color: red;
14
  }
15
}
```
#11667 e997900 Thanks @devtechedge! - Added the nursery rule useBetterDomTraversing, which prefers .firstChild, .firstElementChild, .closest(), and merged .querySelector() calls over positional DOM traversal.
```
1
element.childNodes[0];
2
element.children[0];
3
element.parentElement.parentElement;
4
element.querySelector("a").querySelector("b");
```
#11620 20e513a Thanks @jakeleventhal! - Fixed #11610, #11611, #11612, #11615, and #11616: Biome no longer fully infers an imported generic declaration just to apply its type arguments, restoring type-aware lint performance for large libraries such as Zod. This improves useRegexpExec, noFloatingPromises, noMisusedPromises, useNullishCoalescing, and noUnsafePlusOperands.
#11657 e322040 Thanks @ematipico! - Fixed #7495: noUselessConstructor now ignores TypeScript constructors that forward at least one argument to super, preserving constructors that narrow the subclass’s accepted parameter types. The exemption also applies when the parent and child signatures are identical; JavaScript and zero-argument forwarding behavior are unchanged.
#11670 4969ee1 Thanks @ematipico! - Fixed #7076: useAriaPropsForRole and useFocusableInteractive no longer report non-focusable elements with role="separator". A separator with an explicit tabIndex or tabindex still requires aria-valuenow.
#11627 23aad6d Thanks @ematipico! - Fixed #6571 so Grit plugins can capture and inspect multiple named import specifiers.
#11631 00dbd3a Thanks @ematipico! - Reduced unnecessary type inference when type-aware lint rules inspect members of namespace imports from libraries such as Zod. Fixed type inference so blanket re-exports do not expose default exports.
#11628 a2f8ff7 Thanks @dyc3! - Added the nursery rule noXorAsExponentiation, which reports the bitwise XOR operator ^ between two decimal integer literals, where the exponentiation operator ** was likely intended.
```
1
const kibibyte = 2 ^ 10; // 8, not 1024
```
#11670 4969ee1 Thanks @ematipico! - Fixed #7192: noUnusedPrivateClassMembers now considers compound assignments such as ??= to read and use private class members.
#11676 840a52a Thanks @dyc3! - Fixed #11672 and #11671 by disabling the experimental capitalized-call and effect-dependency checks in useReactCompiler, matching their exclusion from upstream’s recommended lint preset. Valid calls such as Intl.NumberFormat() and captures of variables declared inside effects no longer produce these diagnostics.
#11660 49485ed Thanks @ematipico! - Fixed #11653: Astro template suppression comments ({/* biome-ignore lint: reason */}) now suppress matching HTML lint diagnostics on the following line when full HTML support is enabled.
#11664 9a73b9c Thanks @dyc3! - Improved the performance of useRegexpExec.
#11661 5341b3f Thanks @ematipico! - Fixed #7479. noUnusedVariables now treats Unicode escapes in identifiers as the same binding as their decoded spelling.

#11630 62e1fc5 Thanks @dyc3! - Fixed the HTML formatter inserting whitespace between adjacent Svelte expressions when their combined length exceeds the line width.

1
<span>
2
  {head.median - base.median >= 0 ? "+" : "−"}
3
  {formatMs(Math.abs(head.median - base.median))}
4
  {head.median - base.median >= 0 ? "+" : "−"}{formatMs(Math.abs(head.median - base.median))}
5
</span>

#11658 ed4bfa4 Thanks @fredrikblau! - Fixed #11644: useHeadingContent no longer reports headings that render their text with a directive: set:html and set:text in Astro files, v-html and v-text in Vue files.
```
1
<h1 set:html={heading} />
2
<h2 set:text={heading}></h2>
```
```
1
<template>
2
  <h1 v-html="heading"></h1>
3
  <h2 v-text="heading"></h2>
4
</template>
```
#11613 47d7383 Thanks @ematipico! - Improved the performance of Biome Formatter up to ~50% in some cases.
#11655 fd8fc74 Thanks @ematipico! - Fixed #6974, where noUnusedPrivateClassMembers incorrectly reported TypeScript private constructor properties read through object destructuring from this as unused.
#11618 21a10cf Thanks @siketyan! - Fixed #11605: Type inference now infers the type of an unannotated callback parameter from the signature of the function the callback is passed to, and honours explicit type arguments on call expressions. This improves type-aware analysis for noBaseToString, noFloatingPromises, noMisleadingReturnType, noMisusedPromises, noUnnecessaryConditions, noUnsafePlusOperands, noUselessTypeConversion, useArrayFind, useArraySortCompare, useAwaitThenable, useDisposables, useExhaustiveSwitchCases, useIncludes, useNullishCoalescing, useRegexpExec, and useStringStartsEndsWith. For example, noFloatingPromises can now detect Promises reached through such parameters:
```
1
interface Context {
2
  doSomething(): Promise<void>;
3
}
4

5
declare function test(callback: (ctx: Context) => Promise<void>): void;
6

7
test(async (ctx) => {
8
  ctx.doSomething(); // now reported as a floating promise
9
});
```
#11698 b019982 Thanks @denbezrukov! - Fixed parsing of unquoted CSS URLs beginning with @ or !, such as url(@/assets/icon.svg) and url(!font.woff2). Preserved escaped and non-ASCII whitespace in raw URLs during formatting.
```
1
background-image: url(image\);
2
background-image: url(image\ );
```
#11622 c23e4c7 Thanks @Netail! - Added the nursery rule noUnsafeIframeSandbox, which reports iframe elements whose sandbox attribute combines allow-scripts and allow-same-origin, since that combination lets the embedded document remove its own sandboxing.
```
1
<iframe src="https://example.com" sandbox="allow-scripts allow-same-origin" />
```
#11606 de0528f Thanks @dyc3! - Added the recommended noSvelteAtHtmlTags nursery rule, which reports Svelte {@html} tags that render unescaped HTML.
#11670 4969ee1 Thanks @ematipico! - Fixed #6782: GritQL plugins now match captured JSX component names against code snippets such as React.Fragment.
#11687 09d97d9 Thanks @hori-design! - Fixed #11678: useReactCompiler no longer panics on files that contain non-ASCII characters. This bumps the React Compiler version.
#11595 a64d757 Thanks @dyc3! - Added the nursery Vue-domain rule useVueBaseImport rule, which enforces importing Vue APIs from vue instead of internal @vue/* packages.
#11675 353cbae Thanks @dyc3! - Fixed useReactCompiler silently producing no diagnostics in WebAssembly builds, including the playground.
#11625 ea20e5a Thanks @denbezrukov! - Improved linting performance for large CSS and JSON files.
#11670 4969ee1 Thanks @ematipico! - Fixed #7527: suppression actions for diagnostics emitted on comments are now inserted before the diagnostic comment. In particular, suppressing noTsIgnore now places the biome-ignore comment before @ts-ignore.
#11655 fd8fc74 Thanks @ematipico! - Fixed #8629, where noUnusedPrivateClassMembers incorrectly reported used private TypeScript method overload signatures as unused.
#11669 579f401 Thanks @denbezrukov! - Improved the performance of noExcessiveLinesPerFile when skipBlankLines is false.

2.5.12

Patch Changes

#11440 b88f1ea Thanks @Princesseuh! - Fixed Astro attribute expressions rejecting TypeScript and JSX syntax that is accepted in text expressions.
```
1
<Component icon={<Icon />} count={total as number} onSelect={(e: Event) => e} />
```
#11440 b88f1ea Thanks @Princesseuh! - Fixed Astro attribute names being split on : and . inside an expression, such as {x && <button x-on:keyup.enter={go} client:load.foo />}.
#11440 b88f1ea Thanks @Princesseuh! - Fixed a bare > in the children of an Astro expression being treated as markup, such as {x && <div>a > b</div>}.
#11440 b88f1ea Thanks @Princesseuh! - Fixed HTML comments inside an Astro expression failing to parse. They are now read as trivia, wherever they appear among the children.
```
1
{x && <div>text</div>}
2
{cond && <a></a><b></b>}
```
#11440 b88f1ea Thanks @Princesseuh! - Fixed is:raw children inside an Astro expression being read as JSX, such as {x && <div is:raw>{not js} < & text</div>}.
#11440 b88f1ea Thanks @Princesseuh! - Fixed an apostrophe or quote in the text of a JSX element inside an Astro expression ending the expression early, such as {items.map((i) => <li>it's {i}</li>)}.
#11440 b88f1ea Thanks @Princesseuh! - Fixed the children of a <script> or <style> inside an Astro expression being read as JSX. Their contents are text, so braces and comparisons no longer have to be escaped.
```
1
{cond && <style>a { color: red }</style>}
2
{cond && <script>let x = {a: 1};</script>}
```
#11440 b88f1ea Thanks @Princesseuh! - Added support for template literal attribute values inside an Astro expression, such as {x && <C data-x=`t${x}` />}.
#11440 b88f1ea Thanks @Princesseuh! - Fixed unquoted attribute values being rejected inside an Astro expression, such as {x && <a class=foo maxlength=255 href=/about>go</a>}.
#11440 b88f1ea Thanks @Princesseuh! - Fixed a template literal nested inside ${} breaking the rest of an Astro file, such as const href = `/blog${page === 0 ? '' : `/${page + 1}`}`;.
#11440 b88f1ea Thanks @Princesseuh! - Fixed a quote inside a regex character class breaking the rest of an Astro file, such as const unsafe = /[/"]/;.
#11508 54f3a2e Thanks @dyc3! - Added the nursery rule useFlatMathMinMax. Because Math.min() and Math.max() accept any number of arguments, the rule reports unnecessary nested calls to the same method:
```
1
Math.max(Math.max(a, b), c);
```
The fix flattens this expression to Math.max(a, b, c).
#11585 c5c8315 Thanks @Netail! - Fixed #11475: noUnresolvedImports no longer reports Bun runtime built-in modules (bun, bun:bundle, bun:ffi, bun:jsc, bun:sqlite, bun:test).
#11368 52a57b3 Thanks @Austin1serb! - Fixed #6830: Biome now reports a diagnostic for excessively deep syntax instead of overflowing the native stack while releasing the parsed tree.
#11596 1fc42ed Thanks @dyc3! - Added the nursery rule noThisOutsideOfClass. The rule reports this outside class members and TypeScript functions with an explicit this parameter.
```
1
function Person(name) {
2
    this.name = name;
3
}
```
#11555 2516335 Thanks @dyc3! - Fixed #11529, where noFloatingPromises missed unhandled Promise chains when the imported function’s module belonged to an import cycle. Cyclic modules now preserve types for exports that do not participate in recursive type dependencies.
#11518 0fee70c Thanks @HarperZ9! - Fixed #11500: the formatter now prints the declare modifier before accessibility modifiers on class properties. private declare readonly name: string is now formatted as declare private readonly name: string, matching Prettier and TypeScript’s canonical modifier order.
#11580 1277af2 Thanks @ematipico! - Fixed #5091: Biome no longer moves comments next to the < of a generic, which causes invalid TypeScript syntax:
```
1
Generic<// a comment
2
Generic<
3
  // a comment
```
#11577 42995d2 Thanks @ematipico! - Fixed #4592. Biome no longer crashes while parsing malformed delete expressions.
#11590 67963b4 Thanks @ematipico! - Fixed #6427 so Grit plugins can use function = ... as a node argument.
#11600 a689cb5 Thanks @ematipico! - Fixed #6644: noUnusedVariables now recognizes all interface declarations in a TypeScript declaration-merging group when the interface is referenced.

The following snippet no longer triggers the rule.
```
1
interface Things {
2
    foo: string;
3
}
4

5
interface Things {
6
    bar: string;
7
}
8

9
export type Key = keyof Things;
10

11
interface Things {
12
    baz: string;
13
}
```
#11591 d4a0716 Thanks @ematipico! - Fixed #6615. noDuplicateProperties no longer reports declarations nested in block at-rules as duplicates of declarations in their parent block.
#11492 f2a07aa Thanks @santichausis! - Fixed #11454: noMisplacedAssertion now recognises @fast-check/vitest’s test.prop(...) (and .concurrent.prop, .skip.prop, etc.) as a test function, the same way it already recognises test.each. The JS formatter picks up the same recognition, so a curried test.prop(...)(...) call is now formatted with the regular breakable argument layout used for test.each/test.for, instead of the single-line-hugging layout used for plain it/test calls.

For example, Biome no longer reports the assertion below as misplaced:
```
1
import { fc, test } from "@fast-check/vitest";
2

3
test.prop([fc.string()])("round-trips", (s) => {
4
  expect(s).toBe(s);
5
});
```
#11589 65742b3 Thanks @ematipico! - Fixed #4928: noUnusedVariables no longer reports a value declaration as unused when its merged namespace is referenced.
#11559 472dbc2 Thanks @levrik! - Fixed a false positive in noVueDuplicateKeys where a <script setup> variable initialized from props was reported as a duplicate of the prop it derives from. Biome now exempts any variable whose initializer references props, instead of only recognizing defineProps() and toRefs(props).

For example, Biome no longer reports foo below as a duplicate key:
```
1
<script setup>
2
import { toRef } from 'vue';
3
const props = defineProps(['foo']);
4
const foo = toRef(props, 'foo');
5
</script>
```
#11594 6586ceb Thanks @ematipico! - Fixed #6640. Biome no longer crashes when linting malformed for...of statements.
#11571 85b197d Thanks @ematipico! - Fixed #10838: useSortedAttributes no longer corrupts JSX attributes when nested JSX elements also require sorting.
#11533 97e76c0 Thanks @ematipico! - Fixed #11520, where the Biome scanner would start analysing dependencies multiple times, leading to long and unresponsive sessions.
#11564 18a0e1f Thanks @Netail! - Fixed the diagnostic range of noInferrableTypes so it now highlights only the type instead of including the leading : colon, spaces and comments.
#11540 124fdaa Thanks @ematipico! - Fixed #11537: noShorthandPropertyOverrides now compares declarations only within the same block. The rule no longer reports @supports feature queries and correctly checks nested, @keyframes, and @page blocks.
#11532 7ceb0ee Thanks @dyc3! - Fixed #11528: noFloatingPromises no longer reports statement-level await expressions that handle Promise values, including overloaded calls returning Promise aliases. Awaited values that resolve to arrays of Promises remain reported because their element Promises are not handled by await.
#11474 3c6412e Thanks @dyc3! - Fixed #10241. Biome no longer reports unsupported text expression diagnostics for double-curly text in vanilla HTML, and the formatter preserves adjacent curly-brace text.
#11593 6c7fd27 Thanks @dyc3! - Added the nursery rule noVueDeprecatedScopedSlots. It reports deprecated $scopedSlots references in Vue templates and component objects, and offers an unsafe replacement with $slots. For example, Biome now reports this.$scopedSlots.default inside a Vue component.
#11440 b88f1ea Thanks @Princesseuh! - Fixed the formatter crashing on an Astro or Svelte expression spanning several lines in a file with CRLF line endings, such as <p>{a +\r\n b}</p>.
#11581 f4e5ebb Thanks @dyc3! - Added the nursery rule useModernMathApis. The rule reports legacy mathematical patterns that have direct modern Math equivalents.
```
1
Math.sqrt(a * a + b * b);
```
#11597 a20f44a Thanks @Netail! - Added the nursery rule noBunModules, which forbids the use of Bun builtin modules (e.g. bun:sqlite, bun:ffi).
#11545 7d54688 Thanks @dyc3! - Fixed #11542: Biome now reports HTML comments between Svelte tag attributes as parse errors.
#11582 b6611dd Thanks @ematipico! - Fixed #3862. Biome now parses legacy Internet Explorer filter and -ms-filter values such as progid:DXImageTransform... and alpha(opacity=40).
#11575 65da251 Thanks @dyc3! - Improved the Tailwind parser’s ability to recover from parsing failures. Whitespace now always allows the parser to recover and start parsing a new class.
#11576 0f78499 Thanks @ematipico! - Fixed #3515 and #10395, where Biome could corrupt Unicode characters while writing source received through standard input to standard output. Characters such as ⚠ and ✔ are now preserved.
#11539 0fca643 Thanks @ematipico! - Fixed #11512, where style/noDescendingSpecificity missed lower-specificity selectors after a later higher-specificity selector with the same tail selector.
#11544 040f867 Thanks @dyc3! - Fixed #11541: formatting a Svelte render tag followed by an HTML comment no longer duplicates the comment.
```
1
<div>
2
  {@render children?.()}
3
  
4
  
5
</div>
```
#11565 ee69e0e Thanks @ematipico! - Fixed #11525. Now the configuration schema correctly provides auto-completion for linter domains.
#11583 b19390c Thanks @dyc3! - Fixed #11352: useExplicitLengthCheck no longer reports length-like properties used as value-producing || fallbacks or optional chains, and it no longer offers fixes for value-producing && checks or unsafe negations.
#11562 753e955 Thanks @ematipico! - Fixed an issue where the Biome Language Server would start with logging level set to debug. This would cause logs to grow exponentially in long sessions.
#11217 7d3ee9c Thanks @dyc3! - Fixed handling of biome-ignore format suppression comments on TypeScript declared class properties with string literal names.
```
1
class A {
2
  declare /* biome-ignore format: exercise suppression checking */ 'a-b': 0;
3
}
```
#11497 f5d7896 Thanks @dyc3! - Added the noInvalidFileInputAccept nursery rule. The rule reports invalid literal accept values on file inputs in JSX and HTML, and normalizes common mistakes.
```
1
<input type="file" accept="image/jpg" />
```
#11345 ac58958 Thanks @jakeleventhal! - Improved type inference performance by avoiding resolution of unused members in object arguments.
#11554 2d55931 Thanks @Netail! - Added the new nursery rule useReactNamingConvention, which enforces naming conventions for React values assigned from createContext, useId, and useRef. A value from createContext must be a PascalCase component name ending with Context, a value from useId must be named id or end with Id, and a value from useRef must be named ref or end with Ref.
#11491 1d6210b Thanks @dyc3! - Added the nursery rule noUnmodifiedLoopCondition, which reports variables in loop conditions that are never modified in the loop.
```
1
let node = getNode();
2
while (node) {
3
    process(node);
4
}
```

2.5.11

Patch Changes

#11499 9743d0c Thanks @scs0209! - Fixed #11496: useValidAnchor now treats Astro JSX shorthand attributes like <a {href}> as a valid href.
#11437 88f805e Thanks @Princesseuh! - Fixed #9944: adjacent elements inside an Astro expression now parse as an implicit fragment instead of raising an error.
```
1
{options.map(() =>
2
  <div />
3
  <div />
4
)}
```
#11437 88f805e Thanks @Princesseuh! - Fixed Astro templates rejecting unclosed HTML void elements, such as {cond && <br>}.
#11507 e2fc036 Thanks @dyc3! - Fixed #11157: noUnusedVariables no longer reports Vue <script setup> bindings used by CSS v-bind() as unused.
#11398 afc4615 Thanks @dyc3! - Fixed #11389: Files passed through --stdin-file-path now use full HTML support for Astro, Svelte, and Vue when it is enabled.
#11526 372cd68 Thanks @dyc3! - Fixed noVueRefAsOperand to track Vue refs through declaration aliases and toRefs() properties, and to recognize useTemplateRef() results. The rule no longer reports false positives such as plain ref transfers, plain toRefs() property access, defineModel() modifiers, or the supported .effect member as operands.

The refactor enabling these fixes also improves the performance of the rule.
#11458 a7cd286 Thanks @dyc3! - Fixed #11436: GritQL snippets such as export { $specifiers } from $source now match named re-exports with aliases, inline type modifiers, and multiple specifiers.
#11515 382b15d Thanks @dyc3! - Fixed #11390, where noFloatingPromises performed expensive full type inference for calls to non-Promise methods declared on third-party TypeScript classes. The rule now classifies those calls using targeted type information.
#11516 6f40e82 Thanks @levrik! - Fixed noVueRefAsOperand so it no longer reports a callback parameter (e.g. from .find(), .map()) as an unwrapped ref value just because it’s nested inside a ref(), computed(), or similar call.
```
1
const result = computed(() => list.find((item) => item.label === "a"));
```
Previously, item here was incorrectly treated as a ref value because the rule attributed it to the outer computed() call.
#11495 496268d Thanks @Netail! - Fixed useGraphqlNamingConvention so it no longer reports GraphQL enum value definitions with comments & descriptions and now displays a more accurate diagnostic range.
#11407 6ef52b0 Thanks @1678092075! - Fixed #11214: noUnusedVariables no longer reports type parameters declared by non-default function overload signatures that have an implementation.
#11322 5c353e6 Thanks @jp-knj! - Added a new nursery rule noAstroSetHtmlDirective, which disallows Astro’s set:html directive because untrusted content can introduce cross-site scripting vulnerabilities.

For example, the following snippet triggers the rule:
```
1
<div set:html={content} />
```
#11462 18883b7 Thanks @dyc3! - Fixed #10776: useVueHyphenatedAttributes no longer reports lowercase attribute names containing punctuation, such as pt:header:data-test-id and some_attr.
#11476 3270ca4 Thanks @dyc3! - Fixed #10330: Vue interpolation delimiters now stay attached to whitespace-sensitive element boundaries and adjacent inline siblings, wrapping their expression when needed to fit the configured line width. Interpolations followed by text now also converge after one formatting pass.
```
1
<v-btn v-if="store.state.user" variant="text" to="/my-rooms"
2
  >{{ $t("nav.my-rooms") }}</v-btn
3
>
4
<v-btn v-if="store.state.user" variant="text" to="/my-rooms">{{
5
  $t("nav.my-rooms")
6
}}</v-btn>
```
#11191 3e5367f Thanks @ematipico! - Added the nursery rule noUndeclaredCustomProperties, which reports references to custom properties that are not defined in available CSS, static HTML-like style attributes, or JSX string style attributes.

For example, the following snippet triggers the rule:
```
1
a { color: var(--undefined-color); }
```

#11435 7754894 Thanks @levrik! - Fixed: Variables and imports used as custom Vue directives are no longer reported as unused.

For example:

1
<script setup>
2
const vHighlight = {
3
  mounted: (element) => {
4
    element.style.color = "red";
5
  },
6
};
7
</script>
8

9
<template>
10
  <p v-highlight>Hello</p>
11
</template>

#11501 e6acded Thanks @aminya! - Improved the performance of useArraySortCompare by skipping type inference for calls to unrelated methods.
#11467 66b282c Thanks @dyc3! - Fixed #11464: Biome now parses parenthesized object literals returned from arrow functions when they contain a conditional expression and a nested arrow function.
#11456 db9aa2a Thanks @dyc3! - Fixed #10278: Marked the fix for noThisInStatic as unsafe by default.
#11502 652aedb Thanks @levrik! - noGlobalAssign no longer reports assignments to a Vue <script setup> binding from a template expression, when the binding’s name happens to match a built-in global (e.g. open, parent, top).

For example, this no longer triggers a diagnostic:
```
1
<script setup>
2
const open = defineModel();
3
</script>
4

5
<template>
6
  <button @click="open = !open">Toggle</button>
7
</template>
```

2.5.10

Patch Changes

#11403 8f7786f Thanks @Princesseuh! - Fixed Astro rejecting JavaScript comments between attributes.
```
1
<div /* block comment */ class="something"></div>
2
<Component /* c */ client:load />
```
#11403 8f7786f Thanks @Princesseuh! - Fixed a bare < in Astro text being treated as the start of a tag, such as <p>5 < 6 and 7 > 6</p>. As in HTML, a < that cannot open a tag is text and needs no escaping.
#11438 3133ffa Thanks @Princesseuh! - Fixed #8294: an Astro expression holding only a comment is no longer reported as a parse error, which also stopped the whole file from being formatted.
```
1
<div>{/* a note */}</div>
2
<div class={/* a note */}>x</div>
```
#11403 8f7786f Thanks @Princesseuh! - Fixed #9165: an empty Astro expression such as <div>{}</div> no longer fails to parse. Astro renders {} as nothing.
#11403 8f7786f Thanks @Princesseuh! - Fixed Astro expressions containing a comment failing to parse.
```
1
<div>{/* block comment */ x}</div>
2
<div>{/* only a comment */}</div>
```
#11403 8f7786f Thanks @Princesseuh! - Added support for Astro’s fragment shorthand.
```
1
<>
2
  <p>a</p>
3
</>
```
#11403 8f7786f Thanks @Princesseuh! - Fixed an Astro frontmatter block being cut short by a closing tag inside a string or comment.
```
1
---
2
const a = "</script>";
3
// </script> in a comment
4
---
```
#11403 8f7786f Thanks @Princesseuh! - Fixed --- being read as an Astro frontmatter fence when markup precedes it. Astro only recognizes frontmatter at the very start of a file, so a file opening with a comment now has no frontmatter, and its --- lines are content.
```
1

2
---
3
this is text, not frontmatter
4
---
```
#11403 8f7786f Thanks @Princesseuh! - Fixed an Astro frontmatter block ending early on a line that merely starts with a dash.
```
1
---
2
--count;
3
---
```
#11403 8f7786f Thanks @Princesseuh! - Fixed the children of an Astro element carrying is:raw being parsed as markup instead of raw text. This now also covers <script> and <style>, whose contents Astro emits verbatim rather than processing, so they are no longer linted as JavaScript or CSS.
```
1
<article is:raw><% awesome %></article>
2
<script is:raw>{{ mustache }}</script>
```
#11403 8f7786f Thanks @Princesseuh! - Fixed Astro rejecting attribute names that start with a colon, such as :href.
#11403 8f7786f Thanks @Princesseuh! - Fixed the Astro parser failing to recover from a malformed closing tag such as <div></{<//, so that a later mistake is reported where it happens rather than cascading.
#11403 8f7786f Thanks @Princesseuh! - Fixed { inside an Astro <math> element opening an expression. MathML is foreign content where Astro parses no expressions, so LaTeX such as R^{2x} now survives as text. <svg> is unaffected.
#11403 8f7786f Thanks @Princesseuh! - Fixed {{ at the start of an Astro expression being read as an interpolation. Astro has no {{ }} syntax, so {{ a: 1 }} and <Comp a={{ b: 1 }} /> are object literals.
#11403 8f7786f Thanks @Princesseuh! - Fixed expressions inside an Astro <pre> or <textarea> being read as raw text. Astro parses both as ordinary elements, so their markup and interpolations are now parsed, and a variable used only inside one is no longer reported as unused.
```
1
<pre>{value}</pre>
2
<textarea><div>{value}</div></textarea>
```
#11403 8f7786f Thanks @Princesseuh! - Added support for template literal attribute values in Astro, such as <div class=`a ${b} c`>.
#11403 8f7786f Thanks @Princesseuh! - Fixed Astro rejecting HTML5 unquoted attribute values that contain `, =, ' or ", such as <a href=a=b> and <a href=a'b>.
#11393 dec5a8f Thanks @1678092075! - Fixed #11207: useStrictMode no longer reports Vue event handlers such as @click="count++".
#11431 c065f99 Thanks @levrik! - Fixed #11429: Variables and imports used by Vue same-name bindings such as :disabled or v-bind:disabled are no longer reported as unused.
#11409 405dedb Thanks @ematipico! - Fixed a memory leak in the LSP server where memory usage kept growing over long editor sessions.
#11422 a51eff7 Thanks @dyc3! - Fixed #11416: Biome no longer crashes when parsing incomplete {let} or {const} declarations in Svelte files.
#11378 34b715c Thanks @Netail! - Added extra rule sources from @eslint/css. biome migrate eslint detects rules in your eslint configurations more reliably.
#11403 8f7786f Thanks @Princesseuh! - Fixed {#, {/, {: and {@ being read as Svelte block openings in every HTML-like file. They are now Svelte-only, so in HTML, Vue and Angular files a sequence such as {#if x} is ordinary text instead of a parse error.
#11443 8d45229 Thanks @ematipico! - Fixed #11390: noFloatingPromises no longer performs unnecessary type inference on call arguments when checking methods of non-generic class instances created with new.
#11425 9c2667b Thanks @dyc3! - Fixed #6426: GritQL plugins now match and rewrite metavariables embedded in quoted strings.
#11441 00317c3 Thanks @dyc3! - Improved performance of useNamedCaptureGroup, noMisplacedAssertion, noSkippedTests, noExportsInTest, noDuplicateTestHooks, noIdenticalTestTitle, useTestHooksInOrder, and useTestHooksOnTop.

2.5.9

Patch Changes

#11321 41386f3 Thanks @dyc3! - Fixed #11315: The CSS parser now recovers at declaration boundaries after bogus declarations, allowing subsequent valid declarations to be parsed.
#11248 57b197e Thanks @yanthomasdev! - Expanded the environment variable metadata used by biome rage to include BIOME_BINARY, BIOME_LOG_FILE, and RUST_BACKTRACE as well as reworded explanations for better readability.
#11377 a8798ea Thanks @Netail! - Added a new nursery rule useNamedLayer which disallows anonymous cascade layers.
```
1
@layer {
2
  a {
3
    color: red;
4
  }
5
}
```
#11327 6771cf5 Thanks @dyc3! - The HTML formatter now preserves meaningful blank lines in HTML, including spacing after elements with trailing spaces and blank lines between comment groups.
```
1
<div>
2
  
3

4
  
5
</div>
```
#10312 ba8aa18 Thanks @dyc3! - Added the nursery rule useTailwindShorthandClasses, which suggests shorter Tailwind utility classes. For example, the rule suggests replacing w-4 h-4 with size-4.
#11333 715e0cd Thanks @kkkhs! - Fixed #11328: lint/nursery/useExpect now recognizes Vitest Browser Mode expect.element() calls as assertions.
#11343 9b98211 Thanks @johncarmack1984! - Fixed #11311: the CSS parser now accepts Tailwind container-query variant names in @variant, such as @xl and @max-xl. These previously produced a parse error and a noUnknownAtRules diagnostic.
```
1
@variant @xl {
2
  div {
3
    background: red;
4
  }
5
}
```
#11220 3e8c488 Thanks @santichausis! - Fixed #9541: noUndeclaredVariables, noUnusedImports, and noUnusedVariables now correctly recognise exported variables and functions declared in one embedded <script> block as usable from a sibling <script> block, in Svelte’s <script module>/<script> pair and Vue’s non-setup <script> blocks.

For example, Biome no longer reports greet as undeclared in the following Svelte component:
```
1
<script module>
2
  export function greet() {
3
    console.log("Hello!");
4
  }
5
</script>
6

7
<script>
8
  greet();
9
</script>
```
#11300 36430eb Thanks @dyc3! - Fixed the HTML formatter’s whitespace handling for marquee, noscript, video, audio, and object elements.
```
1
<marquee behavior="alternate"> This text will bounce </marquee>
2
<marquee behavior="alternate">This text will bounce</marquee>
```
#11299 6559e6c Thanks @jp-knj! - Added the nursery rule useAstroClientOnlyDirectiveValue, which reports Astro client:only directives without an initializer.

For example, <Component client:only /> triggers the rule.
#11365 7529811 Thanks @MHJahanbakhsh! - Fixed #11229: The useGenericFontNames rule now treats math as a valid generic font family.

#11346 674f5f4 Thanks @Jayllyz! - Fixed #11335: noComponentHookFactories now reports a use-prefixed variable only when a function is assigned to it directly.

1
function factory() {
2
  const useColors = true; // no longer reported
3
  const useStore = createStore({ count: 0 }); // no longer reported
4
  const useData = () => useState(null); // still reported
5
  return useColors;
6
}

#11334 c87c46a Thanks @zkasuran! - Fixed #11317: noSvgWithoutTitle no longer reports an svg that uses the boolean shorthand aria-hidden (equivalent to aria-hidden={true} in React).
#11364 13853b1 Thanks @ematipico! - Fixed a bug where useJsxKeyInIterable incorrectly flagged Astro files.
#11321 41386f3 Thanks @dyc3! - Fixed #11315: Invalid CSS declarations in HTML style attributes now produce parser diagnostics instead of causing a panic.
#11325 67c3bf0 Thanks @dyc3! - Fixed HTML text wrapping to account for the width of an adjacent closing tag, avoiding lines that exceed the configured width when the final word and tag must move together.
```
1
<a-long-long-long-element
2
  >foo bar foo bar foo bar foo bar foo bar foo bar foo bar</a-long-long-long-element
3
  >foo bar foo bar foo bar foo bar foo bar foo
4
  bar</a-long-long-long-element
5
>
```
#11367 fe5b5d4 Thanks @ematipico! - Fixed TypeScript compilerOptions.paths resolution when mapping targets omit ./. Biome now resolves these targets relative to their configured path base.
#11316 17e48d6 Thanks @wanxiankai! - Fixed #11289: the safe fix for noExtraBooleanCast now preserves parentheses around nested conditional expressions.
#11254 d25d113 Thanks @dyc3! - Fixed #11242: Biome no longer crashes with an access violation when analysing files on Windows ARM64.
#11221 85aac73 Thanks @freeatnet! - Added the nursery rule noUnsafeTypeAssertion, which disallows TypeScript type assertions while allowing const assertions.
```
1
const value = input as SomeType;
```
#11314 7ffb677 Thanks @ematipico! - Fixed #11310: Restored the performance of noMisusedPromises and noFloatingPromises when analyzed expressions share deep imported type paths.
#11356 6cd3263 Thanks @johncarmack1984! - The Tailwind parser now understands modifiers on bare utilities (@container/sidebar, shadow/50).
#11318 76059e9 Thanks @johncarmack1984! - The Tailwind parser now understands container-query variants (@sm:, @max-lg:, @min-[400px]:) and child and descendant variants (*:, **:).
#11357 faa2074 Thanks @johncarmack1984! - The Tailwind parser now accepts the legacy leading ! important marker (!flex, hover:!p-4).
#11344 f34e15c Thanks @johncarmack1984! - The Tailwind parser now understands combinator selectors in arbitrary variants (has-[>svg]:, has-[+p]:), modifiers on variants (group-hover/menu:, @sm/main:), and arbitrary container-query sizes (@[400px]:).
#11324 2f5d452 Thanks @dyc3! - Fixed HTML formatting that inserted rendered whitespace between an element and touching text when the line wrapped.
```
1
<div>
2
  before<meter value=".5"></meter>
3
  after
4
  before<meter value=".5"></meter
5
  >after
6
</div>
```
#11312 e65f07e Thanks @xosnos! - Added a new nursery rule useControlLabel for both HTML and JSX, which reports interactive control elements (button, menuitem) without an accessible label.
```
1
<button />
```
#11364 13853b1 Thanks @ematipico! - Fixed SVG parsing for files with an XML declaration followed by a PUBLIC doctype, such as <?xml version="1.0"?><!DOCTYPE svg PUBLIC "a" "b">.

#11301 610ee28 Thanks @dyc3! - Fixed parent tag wrapping when an HTML element starts or ends with a block-like or hidden child such as source, track, or param.

1
<video src="brave.webm"><track kind="subtitles" src="brave.en.vtt"></video>
2
<video src="brave.webm">
3
  <track kind="subtitles" src="brave.en.vtt">
4
</video>

2.5.8

Patch Changes

#10710 0a0fbc1 Thanks @dyc3! - Added a new nursery rule useReactCompiler, which reports diagnostics from React Compiler lint mode.
#11251 ea9dd8a Thanks @dyc3! - Improved performance of noImportCycles.

#11247 52b44d6 Thanks @dyc3! - Added the nursery rule noSvelteLegacyConst, which disallows legacy Svelte {@const} tags and recommends declaration tags with $derived().

Invalid:

1
{#each boxes as box}
2
  {@const area = box.width * box.height}
3
  <p>{area}</p>
4
{/each}

Valid:

1
{#each boxes as box}
2
  {const area = $derived(box.width * box.height)}
3
  <p>{area}</p>
4
{/each}

#11252 d5f5704 Thanks @Turtle-Hwan! - Fixed #11250: useAwait no longer reports async functions that contain an await using declaration.
#11143 6be7be1 Thanks @vznh! - Fixed #11017: noUselessUndefined no longer reports return undefined when the enclosing function has a return type annotation other than undefined or void.
#11234 caefe39 Thanks @subotac! - Fixed #11228: CSS block comments between a declaration colon and value now preserve their source indentation.
```
1
:root {
2
  --font-stack:
3
/* comment */
4
    /* comment */
5
    system-ui;
6
}
```
#11285 bca1f73 Thanks @denbezrukov! - Fixed #11280: CSS formatting keeps comments inside functional pseudo-classes and pseudo-elements instead of moving them before the function name.
```
1
:/* comment */ where(div) {}
2
:where(/* comment */ div) {}
```
#11080 af16a0b Thanks @dyc3! - HTML style attribute values are now parsed as CSS. All Biome CSS lint rules are applied to the style attributes.
#11195 6a85588 Thanks @dyc3! - Fixed Svelte files failing to parse when an expression begins with an object literal.

Now the following snippet is correctly parsed:
```
1
<p>{{ a: true }}</p>
2
<div class={{ active: isActive }}></div>
```
#11173 481d008 Thanks @Austin1serb! - Fixed #10242: JavaScript GritQL patterns with multiple metavariables now match snippets consistently in WebAssembly.
#11187 23c0369 Thanks @ematipico! - Added the nursery rule noInvalidPropertyInitValue, which reports an @property whose initial-value does not match its syntax descriptor. For example, the following declaration triggers the rule because red is not a <length>:
```
1
@property --size {
2
  syntax: "<length>";
3
  inherits: false;
4
  initial-value: red;
5
}
```
#11272 73896e6 Thanks @ematipico! - Improved the diagnostic emitted by noRootType.
#11240 bd0b68d Thanks @ematipico! - Fixed #11223: Improved the performance of noMisusedPromises when analyzing async class methods that call other methods through this.
#11172 4a0bc5c Thanks @saberoueslati! - Fixed #10806: noUselessFragments no longer causes Biome to panic when its unsafe fix removes a fragment used as a JSX attribute value.
#11227 4d603b0 Thanks @saberoueslati! - Fixed #11178: noUndeclaredVariables no longer reports Vue’s built-in instance properties, such as $slots and $attrs, in template expressions or $event in inline event-handler expressions. The instance properties are still reported inside <script setup>, where they are not defined.
#11187 23c0369 Thanks @ematipico! - Fixed CSS parsing of registered custom properties: Biome now correctly validates the syntax descriptor of @property rules.

2.5.7

Patch Changes

#10822 c171b3b Thanks @pkallos! - Added the option ignoreIfStatements to useNullishCoalescing. Biome now flags if statements that only assign to a nullish variable (such as if (!a) { a = b }) and can rewrite them to ??=. When enabled, Biome ignores those if statements.
#11136 e63354c Thanks @AkashNaickar! - Added a new nursery rule noExtendNative, which reports extending the prototype of a built-in object.
#10094 e007143 Thanks @THEjacob1000! - Added the nursery rule noTailwindArbitraryValue. Biome now reports Tailwind CSS arbitrary values such as w-[400px], including in HTML/JSX class attributes, configured utility functions, and tagged templates.
#11184 135f476 Thanks @subotac! - Fixed #11176: noUnknownPseudoClass now recognizes Vue’s :deep() pseudo-class inside .vue style blocks.
#8239 a519f9d Thanks @cormacrelf! - Fixed #8233, where Biome CLI in stdin mode didn’t work correctly when handling files in projects with nested configurations. For example, with the following structure, --stdin-file-path=subdirectory/... would not use the nested configuration in subdirectory/biome.json:
```
1
├── biome.json
2
└── subdirectory
3
    ├── biome.json
4
    └── lib.js
```
Terminal window
```
1
biome format --write --stdin-file-path=subdirectory/lib.js < subdirectory/lib.js
```
Now, the nested configuration is correctly picked up and applied.

In addition, Biome now shows a warning if --stdin-file-path is provided but that path is ignored and therefore not formatted or fixed.
#11138 8c2c6bd Thanks @ematipico! - Fixed noUnnecessaryConditions: Biome now chooses the same function overload as TypeScript when an argument is a callback, so conditions that were previously missed are reported.

The following code is now invalid, because a parameter typed () => void accepts an async callback and schedule therefore returns string:
```
1
declare function schedule(handler: () => void): string;
2
declare function schedule(handler: () => Promise<void>): string | undefined;
3

4
schedule(async () => {}) ?? "fallback";
```
The following code is also now invalid, because map(() => 42) returns 42:
```
1
type Mapper<T> = () => T;
2
declare function map<T>(mapper: Mapper<T>): T;
3

4
map(() => 42) || flag;
```
#11138 8c2c6bd Thanks @ematipico! - Fixed #11087: noUnnecessaryConditions no longer reports optional chains and nullish coalescing whose receiver can be nullish.

For example, the optional chain and fallback in the following code are no longer reported:
```
1
declare const usage: { range: { startDate: string } } | null;
2
const startDate = usage?.range.startDate ?? "N/A";
```
#11118 9c16840 Thanks @subotac! - Fixed #11098: The HTML formatter now preserves the configured trailing newline when a file ends with a comment.
```
1

2
\ No newline at end of file
3

```
#11201 0e80610 Thanks @Bishwas-py! - Fixed #11182: suppression comments for noPositiveTabindex now suppress the rule in HTML files when the attributes of the element span multiple lines.
#11079 607afd2 Thanks @dyc3! - The HTML formatter now lays out the srcset attribute of <img> and <source> as the list of candidates it is. Runs of whitespace between candidates collapse, and once the list no longer fits on one line each candidate goes on its own line with the descriptors aligned:
```
1
<img srcset="/visual@0.5.png  400w, /visual.png 805w, /visual@2x.png 1610w, /visual@3x.png 2415w" />
2
<img
3
  srcset="
4
    /visual@0.5.png  400w,
5
    /visual.png      805w,
6
    /visual@2x.png  1610w,
7
    /visual@3x.png  2415w
8
  "
9
/>
```
#11156 fed72c7 Thanks @saberoueslati! - Fixed #11129: noUnusedVariables no longer reports Vue bindings as unused when they are assigned through automatically unwrapped template refs.

#11124 d890b39 Thanks @denbezrukov! - Fixed CSS formatting of line comments between a declaration colon and value to preserve their source indentation.

1
.test {
2
  background:
3
  /////// foo
4
  // bar
5
        /////// foo
6
        // bar
7
    radial-gradient(circle, #000, transparent);
8
}

#11113 3d8ab73 Thanks @denbezrukov! - Fixed CSS formatting of long block comments between comma-separated property values:

1
.foo {
2
  box-shadow:
3
    1000px /* long long long long long long long long long long long long comment */ 1000px /* long long long long long long long long long comment */ 2px color(srgb 0.555555555 0.555555555 0.555555555),
4
    1000px
5
      /* long long long long long long long long long long long long comment */
6
      1000px /* long long long long long long long long long comment */ 2px
7
      color(srgb 0.555555555 0.555555555 0.555555555),
8
    1px 1px black;
9
}

#11127 da5c1a5 Thanks @dyc3! - The HTML formatter now picks the quote character for an attribute by counting the quotes in the value rather than looking only for a double quote. ' and " count as the characters they stand for, and only the character that ends up as the delimiter stays escaped:
```
1
<div title='123 &apos;&quot; 456'></div>
2
<div title="123 '&quot; 456"></div>
```
Entities that are not quotes, such as & or &[#39](https://github.com/biomejs/biome/issues/39);, are left exactly as written.
#11193 77035bb Thanks @dyc3! - Fixed the HTML formatter collapsing the blank line between an element and the text that follows it. A blank line before text is now kept, the way one before another element already was:
```
1
<div>foo</div>
2

3
text
```
#11106 ad80f57 Thanks @dyc3! - The HTML formatter now writes the HTML5 doctype in lowercase, matching Prettier:
```
1
<!DOCTYPE html>
2
<!doctype html>
```
This only applies to a plain .html file whose doctype stands alone. A doctype that names a DTD keeps the case it was written with, since the rest of the declaration is not lowercased either:
```
1
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
```
A .vue, .svelte, or .astro file keeps whatever the author wrote.
#11188 60679db Thanks @dyc3! - Fixed the HTML formatter printing a comment twice when it ended the line of the last element in a document:
```
1
text
2
text
```
#11077 4dcd0d9 Thanks @dyc3! - Fixed a bug where the HTML formatter collapsed the whitespace inside <textarea>, <xmp> and <plaintext>, changing what the page renders.
```
1
<textarea>
2
 line one
3
line two </textarea>
4
<textarea>line one line two</textarea>
```
Biome now prints the content of these elements exactly as it appears in the source, matching the existing behavior for <pre>.
#11194 abfbb11 Thanks @dyc3! - Fixed the HTML formatter refusing to format a Svelte file containing an array pattern that skips a position:
```
1
{#each animals as [, value]}
2
  <p>{value}</p>
3
{/each}
```
#10094 e007143 Thanks @THEjacob1000! - Fixed useSortedClasses to correctly detect unsorted classes in static member expression tagged templates (e.g. tw.div\…“). Previously, these were silently skipped due to surrounding whitespace trivia not being stripped from the tag name.
#11078 10da30e Thanks @dyc3! - Fixed Vue single-file components failing to parse when they contain a custom block such as <i18n> or <docs>, or a <template> written in another language. Their content is no longer read as HTML, so a block may hold whatever its own tooling expects:
```
1
<docs>
2
This block is prose, and it may mention a `<my-component>` without closing it.
3
</docs>
4

5
<template lang="pug">
6
  .test
7
    #foo
8
</template>
```
Previously both blocks produced a parse error and the whole file was left unformatted. Biome now prints their content unchanged while still formatting the opening tag.
#11231 4afd901 Thanks @ematipico! - Improved the performance of the following lint rules:
- noArguments.
- noGlobalAssign.
- noUndeclaredVariables.
- noRestrictedGlobals.
- noInvalidUseBeforeDeclaration.
- noShadow.
- noRedeclare.
#11134 2fa0a62 Thanks @yanthomasdev! - Clarified the warning emitted when using the experimental json and json-pretty reporters.
#11198 ed88b13 Thanks @saberoueslati! - Fixed #11171: variables referenced only inside a Svelte attachment ({@attach ...}) are no longer reported as unused by noUnusedVariables and noUnusedImports.
#11155 6ee17ea Thanks @dyc3! - Improved performance when printing diagnostics to the console.
#11160 217f8ad Thanks @dyc3! - Improved the performance of noFloatingPromises by skipping type inference for assignment statements, which are always considered handled.
#11159 26c23d9 Thanks @saberoueslati! - Fixed #11144: noFloatingPromises no longer reports already-awaited optional Promise values.
#11138 8c2c6bd Thanks @ematipico! - Fixed #11121: noUnnecessaryConditions no longer reports conditions based on an inapplicable function overload.

For example, the condition in the following code is no longer reported because query({}) selects the overload that returns boolean:
```
1
declare function query(options: { initial: string }): { isPending: false };
2
declare function query(options: { initial?: string }): { isPending: boolean };
3

4
const { isPending } = query({});
5
isPending || fallback;
```
#11152 c4fc6a9 Thanks @dyc3! - Improved the performance of collecting rule timings with --profile-rules in heavily multithreaded environments.
#11128 4d3ff76 Thanks @ematipico! - Fixed #7635: noDeprecatedImports now detects deprecated ambient declarations that are exported separately.
#11117 01f7ef5 Thanks @subotac! - Fixed #11014: noDelete no longer reports process.env["FOO"] style property deletions.
#11168 9847e68 Thanks @saberoueslati! - Added the nursery rule noNonScalableViewport, which reports viewport metadata that disables user scaling with user-scalable=no.

For example:
```
1
<meta name="viewport" content="width=device-width, user-scalable=no" />
```
#11154 a1d6b1f Thanks @dyc3! - Improved the performance of noImportCycles by skipping graph traversals for imports that cannot be part of a cycle.
#11175 d96d6dd Thanks @ematipico! - Fixed CSS parsing of registered custom properties: Biome now correctly validates the syntax descriptor of @property rules.

2.5.6

Patch Changes

#11035 0e4b03b Thanks @ematipico! - Fixed a performance regression in noMisusedPromises that caused type inference to run repeatedly while linting a file.

#11043 22ec076 Thanks @denbezrukov! - Fixed CSS formatting for multiline function arguments preceded by comments:

1
.example {
2
  value: outer(
3
    1,
4
    /* comment */
5
    nested(
6
      first,
7
      second
8
    )
9
        first,
10
        second
11
      )
12
  );
13
}

#11007 c9acb25 Thanks @BTF-Kabir-2020! - Fixed #9195: useHookAtTopLevel no longer reports hooks in named forwardRef components that receive a ref parameter.
#10152 50a9bd8 Thanks @Zelys-DFKH! - Fixed #10131: Biome now correctly parses curried arrow functions in ternary consequents when the inner arrow’s parameters use a destructuring pattern, e.g. cond ? (x) => ({ a, b }) => body : alt.
#11105 8ffe2b9 Thanks @dadavidtseng! - Fixed #11092: The noUselessTernary quick fix now preserves operator spacing when simplifying or inverting boolean ternary expressions.
#10533 5809875 Thanks @Mokto! - Fixed #10515: biome check --write was not idempotent on Svelte files — multi-line template literals in <script> blocks and block comments in <style> blocks gained an extra indent level on every run.
#11040 0abb620 Thanks @Mokto! - Fixed an issue where the HTML formatter would duplicate a comment placed directly before a Svelte {@const ...} or {@debug ...} block. The duplication compounded on every subsequent --write, causing the file to grow exponentially.
#10858 6d18204 Thanks @ruidosujeira! - Fixed #10839: Svelte {#each} array destructuring no longer includes spaces inside square brackets, and multiline bind function expressions now indent their getter, setter, and function body correctly.
#11009 2c36626 Thanks @ematipico! - Improved the accuracy of type-aware lint rules by resolving more inferred types. For example, noFloatingPromises now detects floating Promises returned by aliased callbacks and arrays of Promises created by async mapping callbacks.

The following statements are now reported:
```
1
type AsyncCallback = () => Promise<void>;
2
declare const callback: AsyncCallback;
3
callback();
4

5
[1, 2, 3].map(async (value) => value);
```
#10973 9cb044c Thanks @ematipico! - Fixed false positives in noMisleadingReturnType when generic-constraint, normalization, substitution, or structural return-type comparison cannot complete. The rule now suppresses diagnostics rather than suggesting a return type derived from partial information. For example, this unresolved return type is no longer reported:
```
1
function unresolvedReturnType(): MissingType {
2
  return "value" as const;
3
}
```
#11071 15047a2 Thanks @dyc3! - The HTML parser now accepts mixed-case doctype declarations.
#11030 cc90e65 Thanks @marschattha! - The rdjson reporter now populates the severity field of each diagnostic (ERROR, WARNING, or INFO), so tools consuming Reviewdog Diagnostic Format output no longer need to assume a default severity.
#11009 2c36626 Thanks @ematipico! - Fixed a performance regression in type-aware JavaScript lint rules by inferring only requested types and memoizing export resolution.
#11056 903b177 Thanks @dyc3! - Added support for Svelte declaration tags using let and const. Biome can now parse, format, and lint bindings declared in these tags.
#11045 89c27c6 Thanks @ematipico! - Improved the performance of Biome formatter up to ~7% across the board.
#9806 781d68d Thanks @dyc3! - Added the nursery rule noJsRestrictedProperties, which ports ESLint’s no-restricted-properties rule. Biome now flags restricted member access and object destructuring, and biome migrate eslint preserves the rule’s options.

2.5.5

Patch Changes

#10972 ab8c21b Thanks @ematipico! - Fixed useExhaustiveSwitchCases for unions of bigint literals. The rule now reports missing bigint cases and compares bigint literals by value, including binary, octal, hexadecimal, and separator-containing spellings. For example, this switch now reports the missing 2n case:
```
1
declare const value: 1n | 2n;
2
switch (value) {
3
  case 1n:
4
    break;
5
}
```
#10972 ab8c21b Thanks @ematipico! - Fixed false positives in noBaseToString and useNullishCoalescing when member, stringification, or nullish inference cannot complete. These rules now suppress diagnostics instead of reporting from partial type information. For example, neither expression is reported when a recursive type cannot be fully resolved:
```
1
type Recursive = Recursive;
2
declare const value: Recursive;
3

4
String(value);
5
value || "fallback";
```
#10977 0bf7486 Thanks @ematipico! - Fixed #10922: the action useSortedAttributes no longer triggers for HTML instructions.
#10957 cf263c4 Thanks @dyc3! - Fixed noThenProperty failing to detect Object.fromEntries, Object.defineProperty, and Reflect.defineProperty calls with comments between their tokens.
#10983 edc0ed7 Thanks @ayaangazali! - Fixed #10980: useAriaPropsSupportedByRole no longer reports false positives when the attribute that determines an element’s implicit ARIA role is written as a shorthand attribute, such as <a {href} aria-label="..."> in Astro and Svelte files.

Shorthand attributes are now taken into account when computing the implicit role, so the anchor above correctly resolves to the link role instead of generic.

#10889 89526e3 Thanks @denbezrukov! - Fixed CSS formatter casing for syntax-owned names while preserving author-defined names, including scoped keyframes and container scroll-state queries.

1
A:HOVER { COLOR: INITIAL; }
2
A:hover { color: initial; }
3
@KEYFRAMES :GLOBAL KeepFrames { FROM { COLOR: RED; } }
4
@keyframes :GLOBAL KeepFrames { from { color: RED; } }
5
@CONTAINER scroll-state((SCROLLED: TOP) AND (STUCK)) { A:HOVER { COLOR: RED; } }
6
@container scroll-state((SCROLLED: TOP) AND (STUCK)) { A:hover { color: RED; } }

#10964 794ccd0 Thanks @denbezrukov! - Fixed CSS formatting for comments between declaration values and !important.
```
1
a { color: /* before */ /* after */ red !important; }
2
a { color: /* before */ red /* after */ !important; }
```
#10993 b7a9694 Thanks @denbezrukov! - Fixed the CSS formatter to preserve comments on the correct side of selector combinators and before declaration blocks.
```
1
.before > /* comment */ .after {}
2
.before /* comment */ > .after {}
```
It now also keeps selectors with escaped newlines in attribute values inline when they fit.
```
1
div
2
  span[foo="bar\
3
div span[foo="bar\
4
value"] {}
```
#10978 8ebafe1 Thanks @ematipico! - Fixed #10870: noUnresolvedImports no longer reports false positives such as import type { NextRequest } from "next/server".
#10901 68c10e6 Thanks @Socialpranker! - Fixed #10622: the HTML/Vue parser no longer panics on the argument-less v-bind shorthand (:="props").

This syntax is valid Vue and equivalent to v-bind="props", so the parser now accepts it (along with the longhand v-bind:="props") instead of crashing while building a diagnostic for a missing argument.
#10936 7df46f5 Thanks @ematipico! - Improved generic tuple inference for useIncludes. The rule now recognizes specialised tuple element types returned through generic aliases.
#10941 f787725 Thanks @siketyan! - Fixed #10855: Biome now supports parsing and formatting CSS custom media queries declared with @custom-media.
#10969 72d309b Thanks @ematipico! - Fixed an issue where Biome logs became too verbose, dumping information not relevant to user’s operations.
e62f6b6 Thanks @ematipico! - Fixed #10963: Biome no longer panics when a type-aware rule such as noFloatingPromises checks a call to a function with multiple call signatures imported from another module.
#10931 899c60d Thanks @ematipico! - Fixed check --write command. Now the command reports code frame of the formatted code, if the formatter is enabled.
#10904 ceee4f4 Thanks @qzwxsaedc! - Fixed #10892: noUnnecessaryConditions no longer reports a false positive when checking a member of a discriminated union that is accessed through a default type-only namespace import. The following code is no longer flagged:
```
1
import type Types from "./types";
2

3
declare function parse(): Types.Result<string>;
4
const result = parse();
5
if (!result.success) {
6
}
```
#10962 f0a67f2 Thanks @ematipico! - Biome no longer removes embedded styles and scripts in HTML files.
#11000 5039a1e Thanks @ematipico! - Fixed a bug where closing one editor stopped a shared Biome daemon used by other editors. LSP proxy processes now exit when either the editor or daemon disconnects.
#10957 cf263c4 Thanks @dyc3! - Improved the performance of the noThenProperty lint rule by about 50%.
#10992 4bf9b21 Thanks @ematipico! - Fixed noMisusedPromises: The rule now reports Promise-returning callbacks where a synchronous callback is expected when calls use tuple spreads or tuple rest parameters, including generic and deeply nested tuples, and when constructor signatures come from interface or object types. Recursive or excessively nested tuple spreads use a conservative fallback so analysis terminates.

For example, the following callback is now reported.
```
1
declare function consume(...args: [number, () => void]): void;
2
const prefix: [number] = [1];
3

4
consume(...prefix, async () => {});
```
#10915 b3b12b3 Thanks @Functionhx! - Added the rule noNegationInEqualityCheck. The rule flags negated expressions on the left side of strict equality checks like !foo === bar — due to operator precedence this evaluates as (!foo) === bar which is almost always a mistake for foo !== bar.

The rule provides an unsafe fix that flips the operator.
```
1
// Invalid
2
!foo === bar;
3
!foo !== bar;
4

5
// Valid
6
foo !== bar;
7
foo === bar;
```
#10970 bd1038b Thanks @ematipico! - Improved overload selection for noMisusedPromises. Biome now handles overloaded calls, overloaded constructors, rest parameters, union arguments, and generic constraints without selecting an incompatible signature. For example, noMisusedPromises now reports the async callback passed to the synchronous overload:
```
1
declare function consume(kind: "async", callback: () => Promise<void>): void;
2
declare function consume(kind: "sync", callback: () => void): void;
3
consume("sync", async () => {});
```
#10933 48a4abb Thanks @ematipico! - Fixed useArrayFind to recognize bigint zero indexes.
#10931 899c60d Thanks @ematipico! - Fixed an orchestration issue that could lead to deadlocks when type-aware rules are enabled.
#10969 72d309b Thanks @ematipico! - Hardened the Biome Language Server by improving its synchronisation logic.
#10972 ab8c21b Thanks @ematipico! - Fixed false positives in noMisusedPromises and useAwaitThenable when Promise or thenable inference cannot complete. These rules now suppress diagnostics instead of treating incomplete type information as a definite result. For example, useAwaitThenable no longer reports await value when the value’s thenability is unknown:
```
1
declare const value: unknown;
2

3
async function consume() {
4
  await value;
5
}
```