Ragnor Comerford 2b2e723125 tests: pin branch_merge swap-restore race (red) ... Per AGENTS.md rule 8, this commit lands the failing regression test ahead of the fix. Cursor Bugbot HIGH on commit 22d76db rediscovered the residual flagged in the round 1 honest-review note: `branch_merge_impl` at `crates/omnigraph/src/exec/merge.rs:1085-1100` still uses the swap_coordinator_for_branch + operate + restore_coordinator pattern across three separate `coordinator.write().await` acquisitions. The same shape that branch_create_from_impl shed in commit 4ffbf6e. The test spawns two concurrent /branches/merge calls A (feature-a → target-a) and B (feature-b → target-b) aligned at a tokio::sync::Barrier so both reach swap_coordinator_for_branch close in time. M=4 iterations boost race-catching odds. Currently fails on 22d76db with target-a=5, target-b=4: B's merge landed on the wrong coord — target-b never got Frank because A's swap pushed self.coordinator to target-a, B's swap captured target-a as B's "previous", and B's restore set self.coordinator back to target-a (not the original main). Subsequent operations using self.coordinator point at the wrong branch. Fix lands in the next commit: serialize concurrent branch merges via `merge_exclusive: Arc<tokio::sync::Mutex<()>>` held across the entire swap-operate-restore window. Closes the bug class "non-atomic three-step coordinator manipulation" for branch_merge by serializing merges relative to each other; per-(table, branch) queue inside the merge body still lets merges and other writers run concurrently. A deeper "operate on local coord" refactor (the round-1 fix shape for branch_create_from) requires unwinding `branch_merge_on_current_target` and its uses of `self.snapshot()` / `self.ensure_commit_graph_initialized()`; deferred to a follow-up. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>		2026-05-08 19:12:03 +02:00
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openapi.rs	MR-771: demote Run to direct-publish via expected_table_versions CAS	2026-04-30 08:52:50 +02:00
server.rs	tests: pin branch_merge swap-restore race (red)	2026-05-08 19:12:03 +02:00