abandon() drained the target's stranded reply once and then reused that same
Reply for every open task it walked past. Two open tickets on one target
therefore both came back REPLIED with the same text — one of them a reply the
worker never gave for that delegation.
One worker answer can settle at most one delegation. It now goes to the oldest
open task (lowest createdNanos) and every other open task keeps the ordinary
WORKER_FAILED path. If the chosen task turns out to be already resolved by
another path, the drained reply is published back to the inbox instead of being
dropped.
reply()'s matching side gets the same rule: more than one candidate means the
reply goes to the inbox rather than to a guess.
Reachability, checked rather than assumed:
- matching.size() >= 2 alone is reachable and was a real bug before this change.
- More than one candidate in reply() is not reachable today — hasAsyncQuestion
matches any task with a stamped turnId, and answer()'s
clearAsyncQuestion(turnId, false) leaves that stamp until the resumed turn
resolves. Kept as defensive code, documented, no test seam added.
- matching.size() >= 2 together with a live strand is not reachable either:
send() and answer() are the only two lock holders and both open a Rendezvous
waiter inside the lock, so "lock held" and "waiter open" are one fact, and an
acceptance always clears the strand first.
I checked the last point by building it in a scratch worktree: it can be forced
by closing an accepted send's waiter directly through Rendezvous, and it does go
red against the pre-fix loop — but that breaks the lock-and-waiter invariant
from outside the class, so no such test is added. A note in abandon()'s javadoc
says so, to save the next reader the same round trip.
Worker's REPORT-cb137.md left out of main.
mvn clean install: Tests run: 1071, Failures: 0, Errors: 0, Skipped: 0
Dai Ha
966c58a3b8