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Fix Await hang when log has no checkpoint - #1202
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PublicationAwaiter's poll loop previously skipped the rest of the iteration when reading the checkpoint returned os.ErrNotExist, so it never broadcast to waiters. Any Await call made before the log had published its first checkpoint would then block forever, never getting a chance to observe that its ctx had been cancelled or had expired. Treat a missing checkpoint as "nothing published yet" (size 0, no error) and fall through to the broadcast, so waiters are woken on every poll and can return once their ctx is done. Adds TestAwait_noCheckpointRespectsContext, which uses testing/synctest to deterministically reproduce the hang. Fixes transparency-dev#1192.
AlCutter
approved these changes
Sep 24, 2026
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PublicationAwaiter's poll loop previously skipped the rest of the iteration when reading the checkpoint returned os.ErrNotExist, so it never broadcast to waiters. Any Await call made before the log had published its first checkpoint would then block forever, never getting a chance to observe that its ctx had been cancelled or had expired.
Treat a missing checkpoint as "nothing published yet" (size 0, no error) and fall through to the broadcast, so waiters are woken on every poll and can return once their ctx is done.
Adds TestAwait_noCheckpointRespectsContext, which uses testing/synctest to deterministically reproduce the hang.
Fixes #1192.