[pjfanning]

Motivation

Shard released its lease in postStop and discarded the returned Future, so a release that failed or returned false was never logged. The shard's next allocation then stalls until the lease times out, and the logs don't say why. This is the same problem as #3685, which #3699 fixes for ClusterSingletonManager.

Modification

• Shard.postStop now calls a releaseLease() helper. It logs an error from the future's callback when the release fails or returns false. The ActorLogging adapter is thread-safe, so it is fine to use after the actor stops.
• A release() that throws synchronously is captured with Try, so the rest of postStop still runs.
• Added TestLease.setNextReleaseResult. It is identical to the version in Release and report singleton leases on manager termination #3685 #3699, so whichever PR merges second only needs a trivial merge.

Result

When a shard stops and its lease is not released, an error naming the type and shard id is logged.

Tests

• sbt "cluster-sharding/testOnly org.apache.pekko.cluster.sharding.ShardWithLeaseSpec": 8 passed. The 3 new cases (release returns false, release future fails, release throws) fail without the Shard change.
• scalafmt run on the changed files.

References

Fixes #3705

[He-Pin]

LGTM. Shard mixes in plain ActorLogging, whose log caches a BusLogging adapter, and it is already initialised during field construction (new Entities(log, ...)), so capturing it in a local before the actor finishes is safe to use from the future callback. Future.fromTry(Try(l.release())).flatten correctly covers both the synchronous-throw and the failed-future cases, and import context.dispatcher is at class scope so it resolves. The tn/id locals are redundant (constructor vals are stable) but harmless. Wording matches the existing ClusterSingletonManager precedent plus Shard's "{}: " typeName convention. TestLease.release() keeps its old default and resets after one use, so other specs are unaffected. Expect a trivial TestLease conflict with #3699 for whichever merges second, as noted.