fix(linter): compatibility issue with `DiagnosticData` type in ESLint by lumirlumir · Pull Request #18396 · oxc-project/oxc

lumirlumir · 2026-01-22T09:11:30Z

Hi, this is my first contribution here, so I'm not sure whether opening a PR directly is appropriate.

If anything is wrong, please let me know!

In ESLint v9.39.2 (which uses @eslint/core@0.17.0), this type was widened to Record<string, unknown>.

Refs:

Refs:

Copilot

Pull request overview

Updates the exported DiagnosticData type to align with the @eslint/core v1.x (ESLint v10 prerelease) definition and avoid type incompatibilities across ESLint versions.

Changes:

Broaden DiagnosticData from Record<string, string | number> to Record<string, string | number | boolean | bigint | null | undefined>.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

overlookmotel · 2026-01-22T14:49:45Z

Yes, it's totally fine to come straight in with a PR for a small change like this. Thanks for getting involved!

Can I just double-check something?

The links you've given to justify this change all point to https://github.com/eslint/rewrite, which I'd understood to be the development space of a way-future version of ESLint. The @eslint/core package bills itself as:

This package is the future home of the rewritten, runtime-agnostic ESLint core.

Is @eslint/core used in present stable ESLint now? (if so, the documentation could be clearer!)

I'm not opposed to this change, just want to double-check our reasoning.

lumirlumir · 2026-01-22T15:06:43Z

Yes, it's totally fine to come straight in with a PR for a small change like this. Thanks for getting involved!

Thanks for the clarification!

Is @eslint/core used in present stable ESLint now? (if so, the documentation could be clearer!)

Yes, I should have been clearer here :)

Currently, both ESLint v9 and the v10 pre-release use @eslint/core under the hood.

Here are the exact package.json references:

ESLint v9.39.2: https://github.com/eslint/eslint/blob/v9.39.2/package.json#L113
ESLint v10.0.0-rc.0: https://github.com/eslint/eslint/blob/v10.0.0-rc.0/package.json#L113

As far as I know, since @eslint/core's early development, it has been used internally by eslint. If you check ESLint v9's package.json for each version, you'll find @eslint/core listed under dependencies.

overlookmotel · 2026-01-22T17:58:41Z

Thanks for coming back. TIL!

overlookmotel

Rebased on main. LGTM.

# Oxlint ### 💥 BREAKING CHANGES - 777fc40 ast: [**BREAKING**] Add `Ident` type (#18354) (Boshen) ### 🚀 Features - 34c3ec3 linter/prefer-logical-operator-over-ternary: Implement fixer (#18545) (camc314) - 019e0aa linter/valid-typeof: Add suggestions if type is misspelled (#18543) (camchenry) - 704c8eb linter/use-isnan: Add more specific error message for equality/inequality (#18542) (camchenry) - 1e99ace linter/use-isnan: Support more `indexOf` cases and improve diagnostic messages (#18537) (camchenry) - bffd134 linter/text-encoding-identifier-case: Add `withDash` option (#18533) (camc314) - 993fd2b parser: Parse unambiguous await with better error messages (#18480) (Boshen) - b4b6247 linter/plugins: `RuleTester` support settings (#18445) (overlookmotel) - 15d69dc linter: Implement react/display-name rule (#18426) (camchenry) - 2fbceae linter: Implement rule docs and config support for rules with tuple config options. (#18372) (connorshea) - 8db0e78 linter/plugins: Handle BOMs (#18376) (overlookmotel) - 6ac09e2 linter/plugins: Support source text not being at start of buffer (#18375) (overlookmotel) - fc3c86b linter: Update 125 rules to raise errors when provided with invalid config options. (#18104) (connorshea) - 2cc6ad2 linter/plugins: Add `ecmaFeatures` to `parserOptions` (#18313) (overlookmotel) ### 🐛 Bug Fixes - 2acf568 linter/plugins: Keep `Infinity` in rule default options (#18550) (overlookmotel) - 332d2ef linter/plugins: Add `jsx` property to `parserOptions.ecmaFeatures` (#18549) (overlookmotel) - 7d9bb1b linter: Update `eslint/func-names` to error on invalid rule config options, improve docs. (#18510) (connorshea) - 9c67974 linter: Improve the jsx-a11y/no-noninteractive-tabindex rule to match original rule logic better (#17848) (connorshea) - 75e7163 vscode: Support json5 for oxfmt (#18502) (Sysix) - c205b0d ast: Remove `ThisExpression` from `TSModuleReference` (#18489) (Boshen) - c51339a oxlint/lsp: Respect code action `source.fixAll` as an alias for `source.fixAll.oxc` (#18366) (Sysix) - 3c0e9b9 oxlint/lsp: Skip dangerous fixes/suggestions for "fix all" code action and command (#18364) (Sysix) - c44c093 linter: Fix behavior of unicorn/catch-error-name to match original rule (#18209) (connorshea) - 9c65aff linter/jsx-a11y: Change `no-autofocus` autofix to suggestion (#18155) (Ben Lowery) - 235c820 linter/unicorn: Fix `prefer-array-some` autofix for `.filter().length` pattern (#18153) (Ben Lowery) - a9925dc linter: Mark fixes in `unicorn/no-null` rule as dangerous. (#18436) (connorshea) - cee29b4 linter: Remove confusing scope from `react/only-export-components` rule diagnostics. (#18434) (connorshea) - aed3669 parser: Parse HTML-like comments in unambiguous mode (#18442) (Boshen) - b8a371d linter: Fix the path used in the gitlab format output (#18165) (connorshea) - e046ea6 linter: `vue/no-lifecycle-after-await` skip looking into arrow functions (#18302) (Sysix) - a9bfbcf linter: Compatibility issue with `DiagnosticData` type in ESLint (#18396) (루밀LuMir) - 10ab424 linter: `react/no_array_index_key` continue search for other attributes (#18409) (Lonami) - 9d776d4 linter: Update `import/no-cycle` rule to error on invalid config options. (#18330) (connorshea) - c163231 linter: Update eslint/sort-imports to validate options. (#18378) (connorshea) - 79bbcff linter: Update `eslint/func-style` to error on invalid configuration options. (#18390) (connorshea) - b871235 linter/plugins: Fix identifying "use strict" directives in scope analysis (#18402) (overlookmotel) - 5985141 linter: Update `jest/prefer-lowercase-title` rule to error on invalid config options. (#18332) (connorshea) - faca4b5 linter/plugins: Tokenize `let`, `static` and `yield` as `Keyword`s (#18368) (overlookmotel) - a3914fd linter/plugins: Allow line number passed to `report` to be 1 over line count (#18341) (overlookmotel) - 88e0896 linter: Update `typescript/no-restricted-types` rule to error on invalid config options. (#18329) (connorshea) - 9eec600 linter: Update `react/jsx-fragments` rule to raise an error on invalid configuration options (#18111) (connorshea) - 0fa969d linter: Update `react/no-will-update-set-state` to error on invalid config options (#18112) (connorshea) - 70e7be4 linter: Update `import/no-unassigned-import` to raise an error when passed invalid config options. (#18108) (connorshea) - 496cac7 linter: Update `unicorn/explicit-length-check` to raise an error when passed invalid config options. (#18107) (connorshea) - 080b1ec linter: Update 5 more rules to error on invalid config options. (#18113) (connorshea) - c5d05dd linter: Update 11 rules to raise an error on invalid config options. (#18109) (connorshea) - 9e359d4 linter/plugins: Set all properties on global vars objects (#18317) (overlookmotel) - 39c7f32 linter/plugins: Set `writeable` flag on variables where defined as globals (#18316) (overlookmotel) - a570693 linter/plugins: Fix `CatchClause` scopes (#18312) (overlookmotel) - 8c98e69 linter: `vitest/prefer-describe-function-title`: Check earlier to avoid false positive (#18177) (Jovi De Croock) - 44be0eb linter/plugins: Set scope analyse settings based on source type (#18306) (overlookmotel) - b9a14fd vscode: Update package.json to restrict a few more config options. (#18270) (Connor Shea) - c1260cb vscode: Update version info formatting. (#18274) (connorshea) - 2f68dc6 vscode: Update notification for client restart to specify tool. (#18273) (connorshea) ### ⚡ Performance - dc931ba linter/no-inner-declarations: Skip scope flags lookup in modules (#18249) (overlookmotel) - 07618a7 linter: Turn off `scope_build_child_ids` for SemanticBuilder (#18360) (Dunqing) - 1aac079 linter/exhaustive-deps: Simplify the logic of checking if the identifier it is a dependency of hook (#18350) (Dunqing) - 591d522 linter/block-scoped-var: Avoid `iter_all_scope_child_ids` by walking references/redeclarations scope ancestors (#18335) (Dunqing) - 2eefd6d linter/plugins: Remove branch from token parsing (#18369) (overlookmotel) ### 📚 Documentation - 698c21d linter: Modernize docs for various React rules (#18559) (connorshea) - 314a47c linter: Clarify the `no-find-dom-node` rule with a note that the method was removed in React 19. (#18556) (connorshea) - 5eff704 linter: Update `no-inner-declarations` to fix config option docs (#18511) (connorshea) - dd5d2f6 linter: Improve diagnostic message in `valid_typeof` rule. (#18507) (connorshea) - 8ccd853 npm: Update package homepage URLs and add keywords (#18509) (Boshen) - 4958233 linter: Add missing "What it does" section in prefer-reflect-apply rule. (#18475) (connorshea) - 2fa83a4 linter: Improve the docs for import/unambiguous. (#18474) (connorshea) - 7b1505c linter: Improve docs for `oxc/only-used-in-recursion` rule. (#18473) (connorshea) - ab506d6 linter/plugins: Correct comment (#18456) (overlookmotel) - 4565c73 linter: `react/display-name`: add docs for config options (#18430) (camchenry) - b95a89f linter: Fix docs for the curly rule. (#18374) (connorshea) - f675eb4 linter: Fix the `react/only-export-components` rule docs. (#18319) (connorshea) - 704db95 linter: "no-unused-vars" extend ignored files section for svelte and astro files (#18304) (Sysix) - 3af4a88 linter: Add "Examples" headers to rules missing them (#18266) (connorshea) # Oxfmt ### 💥 BREAKING CHANGES - 777fc40 ast: [**BREAKING**] Add `Ident` type (#18354) (Boshen) ### 🚀 Features - d71c15d oxfmt: Enable tailwind sort inside xxx-in-js (#18417) (leaysgur) - 52b5003 formatter,oxfmt: Support Angular `@Component({ template, styles })` (#18324) (leaysgur) ### 🐛 Bug Fixes - 224140c oxfmt: Canonicalize `..` component in config path (#18570) (leaysgur) - 30b467e formatter: Preserve trailing comments before the semicolon in class methods without a body (#18446) (Dunqing) - c205b0d ast: Remove `ThisExpression` from `TSModuleReference` (#18489) (Boshen) - 164bbd7 formatter: Preserve trailing comments inside ternary alternate branch (#18433) (Dunqing) - 1c50800 formatter: Use HTML entity escaping for JSX attribute strings (#18385) (Boshen) - 4e156d2 formatter: Preserve parentheses for `in` expressions in arrow function block bodies (#18352) (Boshen) - 7e6c15b oxfmt: Increase Tailwind CSS test timeout for Windows CI (#18339) (Boshen) - 29966eb formatter/dead-code-removal: Handle tailwind sorting (#18321) (leaysgur) - 29f41be formatter: Only expand mapped types when newline immediately follows opening brace (#18087) (Boshen) - 2194552 formatter: Relocate leading comments for single-element union/intersection types (#18083) (Boshen) ### ⚡ Performance - 85ab400 formatter: Store `AstNodes` itself instead of `&'a AstNodes` as the `parent` field of `AstNode` (#18428) (Dunqing) - 194d384 formatter: Reduce AstNode size by 8 bytes using following_span_start (#18347) (Dunqing) - b2df8fb oxfmt: Enable tailwind plugin only for relevant parser (#18418) (leaysgur) ### 📚 Documentation - 8ccd853 npm: Update package homepage URLs and add keywords (#18509) (Boshen) Co-authored-by: Boshen <1430279+Boshen@users.noreply.github.com>

github-actions bot added A-linter Area - Linter A-cli Area - CLI A-linter-plugins Area - Linter JS plugins labels Jan 22, 2026

lumirlumir changed the title ~~fix: compat issue with DiagnosticData type in ESLint~~ fix: compatibility issue with DiagnosticData type in ESLint Jan 22, 2026

lumirlumir changed the title ~~fix: compatibility issue with DiagnosticData type in ESLint~~ fix(linter): compatibility issue with DiagnosticData type in ESLint Jan 22, 2026

github-actions bot added the C-bug Category - Bug label Jan 22, 2026

lumirlumir marked this pull request as ready for review January 22, 2026 09:16

lumirlumir requested review from camc314 and overlookmotel as code owners January 22, 2026 09:16

Copilot AI review requested due to automatic review settings January 22, 2026 09:16

Copilot started reviewing on behalf of lumirlumir January 22, 2026 09:16 View session

Copilot AI reviewed Jan 22, 2026

View reviewed changes

Boshen assigned overlookmotel Jan 22, 2026

fix: compat issue with DiagnosticData type in ESLint

0090bb4

overlookmotel force-pushed the fix/compat-issue-with-diagnosticdata-type-in-eslint branch from 9965750 to 0090bb4 Compare January 22, 2026 17:58

overlookmotel approved these changes Jan 22, 2026

View reviewed changes

overlookmotel merged commit a9bfbcf into oxc-project:main Jan 22, 2026
18 checks passed

Boshen mentioned this pull request Jan 26, 2026

release(apps): oxlint v1.42.0 && oxfmt v0.27.0 #18573

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

fix(linter): compatibility issue with `DiagnosticData` type in ESLint#18396

fix(linter): compatibility issue with `DiagnosticData` type in ESLint#18396
overlookmotel merged 1 commit intooxc-project:mainfrom
lumirlumir:fix/compat-issue-with-diagnosticdata-type-in-eslint

lumirlumir commented Jan 22, 2026 •

edited

Loading

Uh oh!

Copilot AI left a comment

Uh oh!

overlookmotel commented Jan 22, 2026 •

edited

Loading

Uh oh!

lumirlumir commented Jan 22, 2026 •

edited

Loading

Uh oh!

overlookmotel commented Jan 22, 2026

Uh oh!

overlookmotel left a comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Uh oh!

Conversation

lumirlumir commented Jan 22, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

overlookmotel commented Jan 22, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

lumirlumir commented Jan 22, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

overlookmotel commented Jan 22, 2026

Uh oh!

overlookmotel left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

lumirlumir commented Jan 22, 2026 •

edited

Loading

overlookmotel commented Jan 22, 2026 •

edited

Loading

lumirlumir commented Jan 22, 2026 •

edited

Loading