fix(linter/explicit-function-return-type): false negative with HOF detection

[camc314]

fixes #20482

[camc314]

• fix(linter/explicit-function-return-type): false negative with HOF detection #20495 👈 (View in Graphite)
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks
⏩ 52 skipped benchmarks¹

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_{Comparing c/03-18-fix_linter_explicit-function-return-type_false_negative_with_hof_detection (995ac4a) with main (3bbd0cd)}

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

Fixes a false negative in the typescript/explicit-function-return-type rule where return statements inside try/catch were incorrectly treated as “higher-order function” returns, causing missing-return-type diagnostics to be skipped.

Changes:

• Reworked higher-order function detection to scan actual return statements across nested control-flow (including try/catch) and verify their returned expressions are functions.
• Added a new failing test case and updated the snapshot to cover the try/catch scenario from #20482.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
crates/oxc_linter/src/rules/typescript/explicit_function_return_type.rs	Updates HOF detection by walking return statements via an AST visitor; adds a regression test case.
crates/oxc_linter/src/snapshots/typescript_explicit_function_return_type.snap	Updates expected diagnostic snapshot for the new regression case.

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[camc314]

Merge activity

• Mar 18, 10:49 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 18, 10:49 AM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 18, 10:54 AM UTC: Merged by the Graphite merge queue.