test(oxlint/lsp): add lint tests on js side

[Sysix]

No description provided.

[Sysix]

• test(oxlint/lsp): add oxlint.config.ts test #18865
• test(oxlint/lsp): add workspace tests on js side #18774
• test(oxlint/lsp): add lint tests on js side #18730 👈 (View in Graphite)
• test(oxlint/lsp): add init tests on js side #18729
• main

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[Copilot]

Pull request overview

This PR adds comprehensive LSP linting tests on the JavaScript/TypeScript side for the oxlint LSP server. It enhances the diagnostic formatting to include severity levels and adds test cases covering various configuration scenarios.

Changes:

• Enhanced diagnostic formatting in test utils to display severity levels (Error, Warning, Information, Hint)
• Added comprehensive test suite for LSP linting functionality with snapshot testing
• Created test fixtures covering default behavior, configuration options, and custom config paths

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
apps/oxlint/test/lsp/utils.ts	Added DiagnosticSeverity import and enhanced applyDiagnostics function to map and display severity levels in diagnostic output
apps/oxlint/test/lsp/lint/lint.test.ts	New test file with comprehensive test cases for LSP linting using snapshot testing, covering basic linting, config options, and initialization options
apps/oxlint/test/lsp/lint/fixtures/default/test.tsx	Test fixture file for TypeScript React linting with debugger statement
apps/oxlint/test/lsp/lint/fixtures/default/test.ts	Test fixture file for TypeScript linting with debugger statement
apps/oxlint/test/lsp/lint/fixtures/custom-config-path/test.ts	Test fixture file for custom config path testing
apps/oxlint/test/lsp/lint/fixtures/custom-config-path/lint.json	Custom config file setting no-debugger rule to error
apps/oxlint/test/lsp/lint/fixtures/config-severity/test.ts	Test fixture for severity configuration testing
apps/oxlint/test/lsp/lint/fixtures/config-severity/.oxlintrc.json	Config file setting no-debugger to error severity
apps/oxlint/test/lsp/lint/fixtures/config-disabled/test.ts	Test fixture for disabled rule testing
apps/oxlint/test/lsp/lint/fixtures/config-disabled/.oxlintrc.json	Config file disabling no-debugger rule
apps/oxlint/test/lsp/lint/fixtures/config-default/test.ts	Test fixture for default configuration
apps/oxlint/test/lsp/lint/fixtures/config-default/.oxlintrc.json	Empty default config file
apps/oxlint/test/lsp/lint/snapshots/lint.test.ts.snap	Snapshot file containing expected test outputs for all test cases

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[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing 01-30-test_oxlint_add_lint_tests_on_js_side (f76df1b) with 01-30-test_oxlint_lsp_add_init_tests_on_js_side (5544c15)¹}

Summary

✅ 46 untouched benchmarks
⏩ 3 skipped benchmarks²

Footnotes

1. No successful run was found on 01-30-test_oxlint_lsp_add_init_tests_on_js_side (7fb0711) during the generation of this report, so ccdfb09 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 3 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. ↩

[Sysix]

@camc314 @overlookmotel

  [LSP STDERR] 2026-02-03T20:32:12.992453Z DEBUG oxc_language_server::backend: oxc initialized.
  2026-02-03T20:32:12.992897Z DEBUG oxlint::lsp::server_linter: lint /home/runner/work/oxc/oxc/apps/oxlint/test/lsp/lint/fixtures/config-js-plugin/test.js
  
  [LSP STDERR] 2026-02-03T20:32:13.025749Z ERROR tower_lsp_server::transport: failed to decode message: failed to encode response: Resource temporarily unavailable (os error 11)

https://github.com/oxc-project/oxc/actions/runs/21646573385/job/62400049984?pr=18730

I can not explain why this error happens in CI (local without a problem) only with the JS Plugin configuration. This must be in the lint part of LSP-Server. The error message does not really explain much for me, :/ This is probably the return part of the diagnostic request, but I have no knowledge about the OS error :(

[graphite-app]

Merge activity

• Feb 5, 8:47 PM UTC: Sysix added this pull request to the Graphite merge queue.
• Feb 5, 8:55 PM UTC: Merged by the Graphite merge queue.