Discovered blocking this PR's own Windows CI (unrelated to this PR's
actual diff, fixed inline per this repo's no-defer policy): PR #4552's
"full test (windows-latest, 24, shard 2/3)" job failed
tests/check-env.test.cjs's npm-version subtest with "npm binary not
found on PATH" under chunk 5/9's heavy load (51 concurrent files,
5+ minutes). Root-caused via the CI log: the check's spawnSync call
used a 10s timeout, and every failure mode -- ENOENT, a signal-killed
timeout, a non-zero exit, a thrown spawn error -- collapsed into that
one message (only `res.status === 0 && res.stdout` was checked), so a
genuine npm.cmd cold-start timeout under contention was indistinguishable
from npm actually being absent.
Extracted the reason-selection into describeNpmVersionCheckFailure, a
pure function in the new scripts/lib/npm-version-check-diagnosis.cjs
(kept out of check-env.cjs itself, which runs its CLI unconditionally
on require with no `require.main === module` guard, so the pure logic
can be unit-tested without triggering a real environment check).
Reports ENOENT, signal-kill, non-zero-exit, and thrown-error cases
distinctly. Does NOT raise the 10s timeout itself -- a slow subprocess
under contention is a cost to reduce, not a tolerance to widen.
Also fixed a stale tsconfig.build.tsbuildinfo incremental-build cache
discovered while verifying this change: npm run build:lib was silently
omitting gsd-core/bin/lib/markdown-table.cjs (a real, needed compiled
module -- src/state-document.cts requires it), which only surfaced via
npm run lint:generated-sync's gen-health-docs check failing with
Cannot find module. Deleting the cache and rebuilding fresh restored
it; docs/INVENTORY-MANIFEST.json needed no net change once the build
was genuinely complete.
Manually verified describeNpmVersionCheckFailure's five branches
directly (ENOENT, signal-kill, non-zero exit, thrown error, defensive
default) before wiring the test file, since this repo blocks local
node --test. Re-ran node scripts/check-env.cjs directly to confirm the
real success path is unaffected.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>