fix: lake: race condition in monitor queue#13559
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This PR re-enables all of the Lake tests by default. The previous flakiness appears to have been fixed by leanprover#13559, as multiple runs of leanprover#8580 demonstrate. The `LAKE_CI` CMake setting and the `lake-ci` label is kept to potentially enable expensive Lake tests in the future (e.g., the online tests that are not currently run in CI).
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This PR fixes a race condition in the Lake build monitor's draining of the job queue.
Previously, the monitor drained the registered-jobs queue before checking task states. A finished job in that scan may have registered new jobs in its body just before terminating. Those jobs landed in the queue after the drain, so when no other unfinished jobs remained the monitor exited without ever observing them. If one of the missed jobs errors, this could produce an "uncaught top-level build failure" message alongside "Build completed successfully".
To fix this, the monitor loop is restructured so the queue is drained after task states are scanned, with an additional drain before the loop terminates.
drainQueueandscanJobsare split out frompoll, andMonitor.mainperforms an initial drain to capture any jobs registered before the monitor starts iterating. Finishing jobs cannot register further work once their state transitions, so a single post-scan drain is sufficient to close the window.🤖 Prepared with Claude Code