The test swaps the file between the check and the open through a `between` hook. A reference fix
passed it and the gate (769 tests) in the working tree, caught two mutations, and was removed.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Each task's tests were run against a reference at its end state; the end states were replayed
from master in order with the gate at each step (650 to 762 tests); each skeleton compiles
against its tests and fails them. The reference is kept off this machine. Lessons T27 (every
wait in a test has a limit) and T28 (mutate the reference before hand-over) come from this work.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
kyleandClaude Opus 5.5