perf(linter): cache file extension

[camchenry]

Getting file extensions shows up as slow in multiple rules. Computing it once and then storing it should be much faster.

[camchenry]

• perf(linter): cache file extension #14794 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #14794 will not alter performance

_{Comparing 10-19-perf_linter_cache_file_extension (8a1a226) with main (d39bed0)¹}

Summary

✅ 4 untouched
⏩ 33 skipped²

Footnotes

1. No successful run was found on main (46b9d57) during the generation of this report, so d39bed0 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 33 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

This PR optimizes linter performance by caching file extensions to avoid repeated computation. Instead of calling file_path().extension() multiple times across different rules, the file extension is now computed once during context initialization and stored for reuse.

• Adds file_extension() method to ContextHost and LintContext that returns cached extension
• Updates all Vue, React, Jest, ESLint, and Unicorn rules to use the new cached method
• Removes redundant imports and simplifies extension checking logic in several files

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
crates/oxc_linter/src/context/host.rs	Adds file extension caching field and getter method to ContextHost
crates/oxc_linter/src/context/mod.rs	Adds file_extension() method to LintContext that delegates to ContextHost
crates/oxc_linter/src/rules/vue/*.rs	Updates Vue rules to use cached file extension method
crates/oxc_linter/src/rules/react/*.rs	Updates React rules to use cached file extension method
crates/oxc_linter/src/rules/jest/no_large_snapshots.rs	Simplifies snapshot file detection using cached extension
crates/oxc_linter/src/rules/eslint/*.rs	Updates ESLint rules to use cached file extension method
crates/oxc_linter/src/rules/unicorn/no_empty_file.rs	Optimizes extension comparison using cached method

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[Boshen]

Interesting to see this is hot 🤯

[camc314]

Merge activity

• Oct 20, 8:09 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Oct 20, 8:09 AM UTC: camc314 added this pull request to the Graphite merge queue.
• Oct 20, 8:22 AM UTC: Merged by the Graphite merge queue.