Fix race in AsyncPollerTest.testSuspendPolling#2848
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donald-pinckney wants to merge 1 commit intomasterfrom
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Fix race in AsyncPollerTest.testSuspendPolling#2848donald-pinckney wants to merge 1 commit intomasterfrom
donald-pinckney wants to merge 1 commit intomasterfrom
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The test relied on the poller's second iteration racing past its suspend-latch check before the test thread called suspendPolling(). If the test thread won the race, iter 2 blocked at the suspend latch and never reached reserveSlot — so reservedCount stayed at 1 and the later `expected:<2> but was:<1>` assertion failed. Bumping the assertEventually timeout didn't help; the race either wins or loses deterministically on a given run. Remove the race: override reserveSlot on the slot supplier to count invocations, and wait for reserveCalls == 2 before suspending. That's a direct signal that iter 2 has passed the suspend check and called reserveSlot (its future can't complete until iter 1's slot is released, but the call itself happens immediately). After this signal, iter 2 is pinned past the suspend check, so the subsequent suspendPolling() only affects iter 3+. Also drop the now-redundant first assertEventually: once pollLatch counts down (inside the mocked poll()), iter 1's slot has already been issued, so reservedCount == 1 is synchronously visible. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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What was changed
Remove the race: override reserveSlot on the slot supplier to count invocations, and wait for reserveCalls == 2 before suspending. That's a direct signal that iter 2 has passed the suspend check and called reserveSlot (its future can't complete until iter 1's slot is released, but the call itself happens immediately). After this signal, iter 2 is pinned past the suspend check, so the subsequent suspendPolling() only affects iter 3+.
Also drop the now-redundant first assertEventually: once pollLatch counts down (inside the mocked poll()), iter 1's slot has already been issued, so reservedCount == 1 is synchronously visible.
Why?
The test relied on the poller's second iteration racing past its suspend-latch check before the test thread called suspendPolling(). If the test thread won the race, iter 2 blocked at the suspend latch and never reached reserveSlot — so reservedCount stayed at 1 and the later
expected:<2> but was:<1>assertion failed. Bumping the assertEventually timeout didn't help; the race either wins or loses deterministically on a given run.AI Transparency
This PR was fully generated by Claude, and I have not yet reviewed it for accuracy with regards to fixing the flakiness. Don't yet review until I review it more.