[Daniel15]

What changed / motivation ?

Several functions that were deprecated in ESLint 9 were deleted in ESLint 10. This diff removes usage of these legacy functions. The only one that was used in stylex is getFilename(), which has been replaced by the filename property.

https://eslint.org/docs/latest/use/migrate-to-10.0.0#-removal-of-deprecated-context-members

The filename property has existed since ESLint 8, so this will not break any projects that are still on old ESLint evrsions.

Upgrading stylex itself to ESLint v10 is outside the scope of this diff. I tried doing that, but the config file needs to be rewritten as it's in the legacy eslintrc format.

• I have read the contributing guidelines
  Contribution Guidelines
• Performed a self-review of my code

Test plan

All tests for the ESLint plugin still pass:

10:26 danlo@danlo-fedora-MJ0FLNP7 ~/src/stylex/packages/@stylexjs/eslint-plugin  (eslint10)
% yarn test  
...
Test Suites: 9 passed, 9 total
Tests:       546 passed, 546 total
Snapshots:   0 total
Time:        7.338 s

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
stylex	Skipped		May 4, 2026 5:30pm

[Copilot]

Pull request overview

This PR updates the StyleX ESLint plugin toward ESLint 10 by replacing deprecated rule-context filename accessors and aligning the local Flow libdef with the newer context shape.

Changes:

• Replaced context.getFilename() usages with context.filename in two ESLint rules.
• Updated the bundled Flow RuleContext libdef to expose filename, physicalFilename, and cwd properties.
• Kept the scope limited to plugin-side compatibility changes rather than upgrading the monorepo itself to ESLint 10.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
packages/@stylexjs/eslint-plugin/src/stylex-valid-styles.js	Swaps filename lookup to the newer ESLint context property in the main style validation rule.
packages/@stylexjs/eslint-plugin/src/stylex-enforce-extension.js	Swaps filename lookup to the newer ESLint context property in the extension enforcement rule.
packages/@stylexjs/eslint-plugin/flow_modules/eslint/eslint-rule.js.flow	Updates the published Flow libdef for ESLint rule contexts to the newer property-based API.

[Daniel15]

getScope() was removed in ESLint 9, not 10: https://eslint.org/docs/latest/use/troubleshooting/v9-rule-api-changes.

ESLint 9 was released around two years ago. This would have already been an issue? I might need to double-check, but I'm sure that if the lint rule was broken on ESLint 9, we would have heard about it by now.

[Daniel15]

Updating the repo to use ESLint 10 is outside the scope of this diff, since it involves rewriting the config file and ensuring that all lint rules used in the repo are compatible. It can be done in a separate diff.

The fact that the tests pass with ESLint 8 shows that the change is backwards-compatible. Ideally the tests would run with multiple ESLint versions (maybe 8, 9, and 10) but I'm not sure how to do that.

[Daniel15]

Realistically I don't think this would be an issue. ESLint 8 and 9 have these properties too, and I'm not sure how many (if any) downstream users are using Flow along with the types shipped with eslint-plugin. There's a bunch of stuff missing from these types.

[mellyeliu]

Thanks for cleaning this up, it'll be great to get on ESLint 10 soon