fix(linter): merge env from extended config files

[Sysix]

closes #20087
✅ POC: need to check if everything is fine, specially with globals

[Sysix]

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• fix(linter): merge env from extended config files #20088 👈 (View in Graphite)
• refactor(linter): resolve globals from env on build #20100
• fix(linter): check globals entry for no-undef, only check es2026 globals for no-extend-native and no-constant-binary-expression #20089
• main

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[Copilot]

Pull request overview

This PR fixes Oxlint config resolution so that env values are inherited from extended (extends) configuration files, addressing missing globals when env was defined only in a base config.

Changes:

• Update Oxlintrc::merge to merge env from extended configs, with the current config taking precedence.
• Add an OxlintEnv::merge helper to support merging env maps.
• Add a CLI fixture + snapshot test to validate env inheritance and override behavior.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
crates/oxc_linter/src/config/oxlintrc.rs	Merge env from extended configs instead of ignoring it.
crates/oxc_linter/src/config/env.rs	Add OxlintEnv::merge to combine environment maps.
apps/oxlint/src/lint.rs	Add a regression test that runs the new extends_env fixture.
apps/oxlint/src/snapshots/fixtures__cli__extends_env_@oxlint.snap	Snapshot asserting only the override case reports console as undefined.
apps/oxlint/fixtures/cli/extends_env/**	New fixture configs/files covering inheritance + override of env.

[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks
⏩ 52 skipped benchmarks¹

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_{Comparing 03-06-fix_linter_merge_env_from_extended_config_files (1451935) with 03-07-refactor_linter_resolve_globals_from_env_on_build (7f99530)}

Footnotes

1. 52 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.