This commit integrates the scheduler crate's TestScheduler into GPUI's
TestDispatcher for deterministic testing. The TestDispatcher now uses
TestScheduler for:
- Clock/timing (via scheduler.clock())
- Random number generation (via scheduler.rng())
- Block-on tick configuration
GPUI's TestDispatcher maintains its own task queues (foreground, background,
delayed) because it needs to handle RunnableVariant with multiple variants
(Meta, Compat, Scheduler) that TestScheduler cannot process directly.
Key changes:
- TestDispatcher::new() now takes a seed (u64) instead of StdRng
- Clock and RNG are delegated to TestScheduler
- Added RunnableVariant::Scheduler for scheduler-based runnables
- Updated all platform dispatchers to handle the new variant
KNOWN ISSUE: Tests hang after completion. After running the collab
'workspace' tests, the test process hangs indefinitely after these pass:
- test_contact_requests
- test_server_restarts
- test_random_channel_buffers
- test_random_project_collaboration
The hang likely relates to teardown/cleanup when TestDispatcher shares
state with TestScheduler. Need to investigate:
1. Whether blocked_sessions in TestScheduler is properly cleaned up
2. Whether there are threads being parked that never get unparked
3. Whether the test macro teardown sequence interacts badly with scheduler
9272b90672