Fix flaky code patch acceptance test caused by Monaco diff race#4225
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Fix flaky code patch acceptance test caused by Monaco diff race#4225
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During test teardown, Monaco's WorkerBasedDocumentDiffProvider.computeDiff can receive a null result from the editor worker when models are disposed mid-computation. This caused an unhandled "no diff result available" error that surfaced as a flaky QUnit global failure in CI. Extend the existing Monaco patch to return an empty diff result instead of throwing — matching the pattern Monaco already uses for disposed models. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Pull request overview
This PR addresses a flaky Monaco-driven acceptance test by hardening Monaco’s worker-based diff computation against a null diff result during teardown/model disposal, avoiding an exception that bubbles up as a QUnit global failure.
Changes:
- Extend the existing
monaco-editor@0.52.2patch to return an empty diff result when the worker returnsnullinstead of throwing. - Update
pnpm-lock.yamlpatched dependency hash entries to reflect the modified Monaco patch.
Reviewed changes
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| File | Description |
|---|---|
patches/monaco-editor@0.52.2.patch |
Changes Monaco’s WorkerBasedDocumentDiffProvider.computeDiff behavior on null results to return an empty diff instead of throwing. |
pnpm-lock.yaml |
Updates the patch_hash/patched dependency hash for monaco-editor@0.52.2 to match the new patch content. |
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- pnpm-lock.yaml: Language not supported
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Address review feedback: instead of unconditionally returning an empty diff when the worker returns null, only suppress the error when the models are confirmed disposed (the teardown race). Genuine worker failures with live models still throw. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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* Fix flaky "Accept All" code patch test caused by Monaco diff editor race During test teardown, Monaco's WorkerBasedDocumentDiffProvider.computeDiff can receive a null result from the editor worker when models are disposed mid-computation. This caused an unhandled "no diff result available" error that surfaced as a flaky QUnit global failure in CI. Extend the existing Monaco patch to return an empty diff result instead of throwing — matching the pattern Monaco already uses for disposed models. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com> * Narrow Monaco patch to only suppress error when models are disposed Address review feedback: instead of unconditionally returning an empty diff when the worker returns null, only suppress the error when the models are confirmed disposed (the teardown race). Genuine worker failures with live models still throw. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
WorkerBasedDocumentDiffProvider.computeDiffcan receive anullresult from the editor worker when models are disposed mid-computation. This threwError: no diff result availablewhich surfaced as a flaky QUnit "global failure" in CI on the "Accept All" code patch acceptance test.patches/monaco-editor@0.52.2.patch) to return an empty diff result instead of throwing — matching the pattern Monaco already uses for the disposed-models case a few lines above in the same method.Test plan
failure patching code when using "Accept All" button) — passesCode patches testsacceptance suite (17 tests) — all pass (15 pass, 2 skipped, 0 failures)🤖 Generated with Claude Code