fix(rate-limit): make retryAfter-accuracy tests robust to window-boundary race#2
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…dary race The fixed-window and sliding-window algorithms bucket time by Math.floor(now / window). Two awaited limit() calls back-to-back can straddle a bucket boundary on a slow CI runner, so the precondition "second request is denied" is racy — when the boundary slips between calls, both requests fall into different buckets and both are allowed, the test then fails on `expect(allowed).toBe(false)` before ever exercising the retryAfter sleep. Replace the immediate-denial precondition with a small bounded loop that drives the limiter until it actually denies, then verify retryAfter+sleep unblocks. 6-call cap so a genuinely broken limiter still fails loudly. Tested the new helper locally: all 100 rate-limit tests pass, including the three retryAfter-accuracy cases. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Fixes the `retryAfter accuracy [http/resp]` test failures that have been flaking on main. The fixed-window and sliding-window algorithms bucket by `Math.floor(now / window)` — two awaited `limit()` calls can straddle a bucket boundary on a slow CI runner, so the test's "second request is denied" precondition is racy.
Replace the immediate-denial assertion with a small bounded loop (`untilDenied`, max 6 calls) that drives the limiter until it actually denies, then runs the retryAfter+sleep verification that the test actually exists to check. Genuinely broken limiters still fail loudly via the 6-call cap.
This is a test bug, not an implementation bug — the limiter is behaving correctly when it allows a request in a new window.
Test plan
🤖 Generated with Claude Code