phase-merge's state-only path merges a head whose CI is still Running #593

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opened 2026-09-21 14:50:30 +00:00 by claude · 1 comment

claude commented

2026-09-21 14:50:30 +00:00

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Found during IW-491.

When only review-state.json has changed since ci_gated_sha, phase-merge takes one CI reading and does not wait (core/commands/PhaseMerge.scala:187-196). A Running reading is accepted, so the merge can land a head whose own run has not finished. Commit 9d577408 made this trade on purpose: the changed head differs from the gated head only in the card.

The trade is weaker than it looks. The run on the new head can still fail (a flaky job, a CI change on main), and nothing records that the merged head was never judged.

PROPOSED FIX. Decide explicitly. Either wait for a terminal verdict on the state-only path too, or keep the trade and write on the merged card that the merged head was not judged.

Found during IW-491. When only `review-state.json` has changed since `ci_gated_sha`, `phase-merge` takes one CI reading and does not wait (`core/commands/PhaseMerge.scala:187-196`). A `Running` reading is accepted, so the merge can land a head whose own run has not finished. Commit `9d577408` made this trade on purpose: the changed head differs from the gated head only in the card. The trade is weaker than it looks. The run on the new head can still fail (a flaky job, a CI change on main), and nothing records that the merged head was never judged. PROPOSED FIX. Decide explicitly. Either wait for a terminal verdict on the state-only path too, or keep the trade and write on the merged card that the merged head was not judged.

claude referenced this issue

2026-09-21 14:52:17 +00:00

IW-491: phase-pr pushes a commit after reading CI, so its green can describe a stale head #596

claude referenced this issue

2026-09-21 19:32:19 +00:00

The phase gate reads and writes cards that do not belong to the head under test #601

claude commented

2026-09-21 19:32:25 +00:00

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Closed as a duplicate of #601, which takes this defect and three others as one investigation on one branch. This one is phase 4 there.

The four share a cause: the card and the CI reading do not agree on which head they speak about. Fixing them apart would read the same code four times.

Closed as a duplicate of #601, which takes this defect and three others as one investigation on one branch. This one is phase 4 there. The four share a cause: the card and the CI reading do not agree on which head they speak about. Fixing them apart would read the same code four times.

claude closed this issue

2026-09-21 19:32:25 +00:00