bump-leg.py _ensure_root_clean, scaffold-project.py _shape_revision and family.py _shape_snapshot read git status --porcelain through git_out, which decodes strictly, so a file name that is not UTF-8 under core.quotePath=false ends them in a UnicodeDecodeError traceback, exit 1, where bump-leg owes bump-leg-root-dirty (exit 2) and the other two owe a WARNING that the standard's checkout is dirty #423

(lane openRepoShape-2, 2026-10-12T17:25Z)

Found by this lane's review of PR #352 (the fix for #289) at 107242d, its follow-up FU2, and widened here to the two other callers of the same read. The same on main with and without #352 (its head does not touch these lines), so no open PR causes it. Reproduced on origin/main 92e29d9 (git 2.43.0, Python 3.12.3), local remotes only, a stub gh. Not claimed.

What is wrong. Three tools ask git status --porcelain through repo_shape.git_out and read the answer as text. git_out decodes the output strictly, proc.stdout.decode("utf-8") (scripts/repo_shape.py:843), and raises Refusal only for a git exit code. With the default core.quotePath git prints a non-ASCII file name C-quoted (".github/workflows/caf\351.yml"), which decodes. With core.quotePath=false it prints the raw bytes, and a name that is not UTF-8 (a name made under a legacy code page, a checkout from a filesystem that stores such names) ends the run in a UnicodeDecodeError traceback, exit 1, before anything the tool exists to say:

• scripts/bump-leg.py _ensure_root_clean (:669, in the function that starts at :655) asks status --porcelain --untracked-files=no and prints each dirty line; the refusal it should give is bump-leg-root-dirty (exit 2), and it gives a traceback under --dry-run as well. It is the first read cmd_bump makes after the arguments (:1106), so nothing has moved yet;
• scaffold-project.py _shape_revision (:901) asks status --porcelain of the standard's own checkout (SHAPE_ROOT) to warn that it is dirty, and only the emptiness of the answer is used;
• scripts/family.py _shape_snapshot (:761) asks the same for family.py init.

For the last two the traceback comes before a remote is created (no remote exists afterwards), so a dirty standard's checkout with one such file blocks every scaffold and every family.py init run from it, where the code means to print a WARNING and go on.

# $U: a checkout of openRepoShape at 92e29d9. $C: an assembly root on a bump branch, cloned from a local scaffold; $NEW a new commit on its spec leg's remote. Local; no network.
printf 'on: [push]\n' > "$C/.github/workflows/$(printf 'caf\xe9.yml')"; git -C "$C" add -A .github/workflows && git -C "$C" commit -qm w
printf '# edited\n' >> "$C/.github/workflows/$(printf 'caf\xe9.yml')"
git -C "$C" config core.quotePath false
python3 "$U/scripts/bump-leg.py" --root "$C" --leg spec --to "$NEW" --local-remote-dir "$D/remotes" --dry-run
#   exit 1
#   Traceback ... bump-leg.py line 1106, in cmd_bump -> _ensure_root_clean -> repo_shape.py line 843, in git_out
#   UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe9 in position 24: invalid continuation byte
git -C "$C" config --unset core.quotePath                                                  # the control
python3 "$U/scripts/bump-leg.py" ... --dry-run                                             # exit 2, REFUSED bump-leg-root-dirty:  M ".github/workflows/caf\351.yml"

What it should do. Each read keeps what git wrote: ask with binary=True and decode in the caller, for display only. _ensure_root_clean decodes with errors="surrogateescape" or "replace" and then gives its refusal over the dirty names, exit 2; _shape_revision and _shape_snapshot need only whether the answer is empty, so bool(git_out(..., binary=True)) is enough. Do NOT change git_out: scripts/repo_shape.py is a pinned copy (COPIED_FROM_SHAPE), so a change there moves the sha256 that every scaffolded and adopted project's contracts/shape-pin.yaml records for it, and every project already cut sees it as upstream-changed (#292 makes the same point for adopt). The three callers are in files no project pins.

How to test. In tests/test_bump_leg.py's harness (a scaffolded root on a bump branch, core.quotePath=false, a tracked file named with b"\xe9" and an edit): bump-leg.py and --dry-run exit 2 with bump-leg-root-dirty, the name is printed, and the tree is unchanged; the same with the default quoting; a UTF-8 name as a control. For the other two: a dirty copy of the standard (git archive into a fresh repository, as the scaffold tests do) with an untracked non-UTF-8 name and GIT_CONFIG_COUNT/GIT_CONFIG_KEY_0=core.quotePath in the environment: the scaffold and family.py init --dry-run print the DIRTY warning and exit 0. A name that is not UTF-8 needs a POSIX filesystem; skip on Windows and macOS (macOS rejects the byte).

Not in this issue. adopt-project.py's own git_out reads (#292, PR #353), _default_branch's branch name and the other callers that ask for names (ls-files, ls-tree) which already pass -z and binary=True. bump-leg.py's unreadable workflow and pin files (#289, PR #352; the permission cases #383, PR #403).

Related: #289 and PR #352 (the review's FU2); #292 and PR #353 (the adopt analogue); #230 (the readers that were moved to UTF-8 explicitly).

Lane: openreposhape-2 (openRepoShape-2)