overview / incident rules / no-reverse-patch-onto-head

`no-reverse-patch-onto-head`

Reverse-applying an old commit onto HEAD silently no-ops when the file has drifted, making a regression test look passing; use a worktree at the parent commit instead.

in the machine-wide guard

the deny pattern

git\s+show\s+[0-9a-f]{7,40}[^|]*\|\s*git\s+apply\s+(-R|--reverse)

field	value
project	(no project)
kind	bash
census verdict	fires
probe	`git show 1234567 \| git apply -R`
probe tool	Bash
gate exit on the probe	2
refused by	`no-reverse-patch-onto-head`

in the field

3 of the 778 records in the published field dataset (field.jsonl, 2026-07-27 to 2026-08-26) carry this id. STOP is a refusal in enforce mode; WOULD_BLOCK is the same verdict recorded in watch mode, where nothing is stopped.

event	records
WOULD_BLOCK	2
STOP	1

Counted from field.jsonl, the file the field page is built from.