fix: don't advance eventlog LastSeq() until the write is confirmed - #47
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AmirF194 wants to merge 1 commit into
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fix: don't advance eventlog LastSeq() until the write is confirmed#47AmirF194 wants to merge 1 commit into
AmirF194 wants to merge 1 commit into
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Log.Append incremented l.last before attempting the write, so a failed write left LastSeq() pointing past a gap that Since() answers as empty instead of unanswerable. Session.Attach trusts since<=LastSeq() as proof the log can serve a resume, so the documented snapshot fallback never fired and a reconnecting viewer was left silently stuck. Fixes tokencanopy#46
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Log.Appendincrementedl.lastbefore attempting the write, so a failed write (or flush) leftLastSeq()pointing at a seq that never made it intol.entries.Session.Attachtrustssince <= LastSeq()as proof the log can answer a resume, so when the failed Append was the most recent one,Since(since)came back empty across that gap instead of erroring, and the documented snapshot fallback never ran.Moved the
l.lastassignment to right after the write and flush succeed, next to where the entry gets appended tol.entries, so the counter and the replay buffer always move together.Added
TestFailedAppendDoesNotAdvanceLastSeq: append one entry, close the underlying file to force the next write to fail, then assertLastSeq()andSince(0)still only see the one entry that actually landed. The new test fails without the change, atLastSeq() after failed Append = 2, want 1. Raninternal/eventlogandinternal/sessionwith-race, andmake verify(module-path, protocol/control guards, full suite, build, vet) clean.Fixes #46