The guard judged substantive contract updates by diffing HEAD against
the index. In CI nothing is staged, the index equals HEAD, so every
contract file piped in via --files-from-stdin looked unchanged and the
guard blocked compliant pushes. Concretely, run 28944317805 blocked
7645965af even though its deployment-installability.md addition sits
inside the Current State section.
The guard now accepts --diff-base <ref> (requires --files-from-stdin),
resolves it to its merge base with HEAD so the comparison anchor
matches the three-dot changed-file list, and compares base vs HEAD
contract texts in that mode. Pre-commit keeps the index comparison.
The canonical-governance workflow passes the push or PR range base.
contract_patch_has_substantive_change walked git diff --unified=1000
output and tracked the last ## header seen in the patch, so an edit
more than 1000 lines below its section header (e.g. deep inside
unified-resources.md's Current State) lost its section and was wrongly
reported as not substantive, forcing a contract-neutral bypass on
74131e56e.
Replace the patch walk with full-file attribution: diff the HEAD blob
against the staged blob and map every changed line to its section via
a per-line section map built from the complete file. Covers new
contract files (empty HEAD blob) and keeps metadata-only edits
non-substantive. Adds regression tests for edits >1000 lines below
their section header in both directions.
Introduce PULSE_ALLOW_CONTRACT_NEUTRAL_COMMIT as a narrow escape
hatch for the canonical-shape block in staged_commit_shape_guard
and canonical_completion_guard. A non-empty reason logs to stderr
for audit and suppresses only the canonical-shape requirements;
lane-progress, promotion-proof, sensitivity, gitleaks,
governance-stage, control-plane, status, registry, and contract
audits still run. Previously a behavioral bug fix on a canonical
runtime path demanded full contract + verification ceremony even
when no public-contract delta existed, forcing --no-verify.
rcourtman