23fdfcf pinned shellcheck because a version split between CI and developer
machines kept the workflow red for a day. The same trap was still open for
every other `language: system` tool, so close it for all of them.
The risk is not identical across the four, and the code says which is which:
shellcheck, zsh run in CI. Drift shows up as a CI failure the developer
cannot reproduce -- the b83ce5d case exactly.
prettier, shfmt never run in CI (pre-push and local git hook). They
REWRITE files, so two developers on different versions
reformat the repo back and forth.
check_shellcheck_version becomes a table-driven check_pinned_tool_versions
over PINNED_TOOL_VERSIONS, and _tool_version normalises the four different
formats these tools report (shellcheck's `version:` line, shfmt's leading v,
zsh's second field). zsh is compared on major.minor only: apt cannot select a
patch release on the runner image, so 5.9.2 vs 5.9 is not a real divergence
and must not become a permanent warning.
CI gains a step installing prettier at an exact npm version and shfmt from a
checksum-verified release binary, each asserting what PATH actually resolves
to afterwards. Those two are unexercised by the current job by design -- the
pin records the expected version in one place and protects any future
workflow that does run them.
Verified: YAML parses with all pins ahead of the hook step; the shfmt install
ran verbatim with `sha256sum --check --strict` reporting OK and the version
gate passing; prettier@3.9.5 resolves from the registry; the drift warning
fires per-tool against stubbed prettier 3.0.0 and shfmt v3.0.0 (confirming v
normalisation and that it reports every drifted tool, not just the first) and
stays silent against the real toolchain; common.sh is shellcheck clean after
rewording a comment that began "# shellcheck, zsh --" and was being parsed
as a malformed directive; 1193 Python tests at 100% coverage.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018ReVsw7qovYkkGbqcU9tn7