Fix flaky "clear removes all entries" test#370
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`URLCache.removeAllCachedResponses()` is asynchronous — the in-memory cache may still serve stale entries after the call returns. Verifying through a fresh `EditorURLCache` instance bypasses the in-memory layer and reads only from disk. --- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
Temporary change to validate the flaky test fix. Remove `parallelism: 50` before merging. --- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
mokagio
added
the
[Type] Automated Testing
Reusing the same directory after `clear()` still races — the old `URLCache` instance's async removal can clobber the new instance's writes. A separate `cacheRoot` eliminates the race entirely. --- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
Validation complete — all 50 runs passed on build #1646. --- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
Replace the fresh-instance workaround with an exponential backoff poll (0.05s → 1s timeout) that waits for `URLCache.removeAllCachedResponses()` to actually take effect on the same cache instance. Re-adds `parallelism: 50` for CI validation — remove before merging. --- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
Validated across 100 runs (builds #1646 and #1648) with zero failures. --- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
--- Generated with the help of Claude Code, https://claude.ai/code Co-Authored-By: Claude Code Opus 4.6 <noreply@anthropic.com>
jkmassel
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Mar 17, 2026
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waitForClearToTakeEffect
Welp I surely hate this.
But it works, so let's ship it :)
I think this is a pretty strong sign that we shouldn't use URLCache for anything though...
Thanks for taking care of this Gio!! 🙇
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What?
Run into flaky tests working on #318. Got an agent to fix it. Took a few iterations, but got there in the end. This fixes flaky
EditorURLCacheTests.clearRemovesAlltest.Why?
URLCache.removeAllCachedResponses()is asynchronous — the in-memory cache may still serve stale entries after the call returns.The existing 0.2s sleep is not enough under CI load, causing intermittent failures.
How?
The two
clear()-related tests now verify through a freshEditorURLCacheinstance pointing to the samecacheRoot.A new instance bypasses the in-memory layer and reads only from disk, making the assertion deterministic.
The pipeline temporarily runs Swift tests 50x in parallel (
parallelism: 50) to validate the fix.Remove before merging.
Testing Instructions
clear removes all entriesandstore succeeds after cleartests should no longer flake.Posted by Claude Code (Opus 4.6) on behalf of @mokagio with approval.