fix(adr): a record freezes at the merge that lands it

Makefile

@@ -372,6 +372,7 @@ test-adr:
 	@bash tests/adr-archive-test.sh
 	@bash tests/adr-golden-test.sh
 	@bash tests/adr-macro-test.sh
+	@docs/scripts/adr lint --check >/dev/null || { docs/scripts/adr lint; exit 1; }
 	@echo "adr tool tests passed."
 
 test-unit:

hooks/ways/documentation/adr/adr-tool

@@ -1397,10 +1397,13 @@ def _frozen_snapshot(adr) -> Optional[tuple]:
     # A record freezes where it lands: history is read from the default
     # branch when there is one, so a decision still in review on a feature
     # branch can be revised. Without a remote default, HEAD's history counts.
+    # --first-parent keeps to the branch's own line, so a pull request merged
+    # with a merge commit lands at the merge, not at the first commit on its
+    # branch; -m lists the merge's files against that parent on older git.
     ref = (_git(['rev-parse', '--abbrev-ref', 'origin/HEAD'], root) or '').strip() or 'HEAD'
     # --reverse drops pre-rename history under --follow, so read newest first
     # and reverse here. -z keeps names with spaces or non-ASCII intact.
-    log = _git(['log', ref, '--follow', '-z', '--format=commit:%H', '--name-only', '--', str(rel)], root)
+    log = _git(['log', ref, '--first-parent', '-m', '--follow', '-z', '--format=commit:%H', '--name-only', '--', str(rel)], root)
     if not log:
         return None
     entries, commit = [], None

hooks/ways/documentation/adr/src/rules_v1_integrity.py

@@ -147,10 +147,13 @@ def _frozen_snapshot(adr) -> Optional[tuple]:
     # A record freezes where it lands: history is read from the default
     # branch when there is one, so a decision still in review on a feature
     # branch can be revised. Without a remote default, HEAD's history counts.
+    # --first-parent keeps to the branch's own line, so a pull request merged
+    # with a merge commit lands at the merge, not at the first commit on its
+    # branch; -m lists the merge's files against that parent on older git.
     ref = (_git(['rev-parse', '--abbrev-ref', 'origin/HEAD'], root) or '').strip() or 'HEAD'
     # --reverse drops pre-rename history under --follow, so read newest first
     # and reverse here. -z keeps names with spaces or non-ASCII intact.
-    log = _git(['log', ref, '--follow', '-z', '--format=commit:%H', '--name-only', '--', str(rel)], root)
+    log = _git(['log', ref, '--first-parent', '-m', '--follow', '-z', '--format=commit:%H', '--name-only', '--', str(rel)], root)
     if not log:
         return None
     entries, commit = [], None

tests/adr-golden-test.sh

@@ -307,6 +307,20 @@ fresh v1
 edit docs/architecture/system/ADR-110-old-v0-record.md "s.replace('status: Accepted\n', 'contract: adr/v1\nkind: decision\nverb: add\ncapability: ingest\nstatus: accepted\nagent: {name: Claude, model: fixture-model}\nbasis:\n  - evidence: migrated from v0\n').replace('# ADR-110: An unmigrated v0 record\n', '# ADR-110: An unmigrated v0 record\n\n## Summary\n\n- **Probes:** *Confident:* a. *Not confident:* b.\n- **Inversion:** c.\n')"
 capture v1-frozen-migrated lint docs/architecture/system/ADR-110-old-v0-record.md
 
+# A record accepted on a review branch and revised there freezes where it
+# merges, not at the branch's first accepted commit; editing it after the
+# merge still fails.
+fresh v1
+(cd "$WORK/repo" && git switch -q -c review)
+edit docs/architecture/system/ADR-113-operator-proposed.md "s.replace('status: proposed\n', 'status: accepted\nconsidered: [{operator: developer, said: \"yes\", via: PR 13}]\n')"
+commit_all accept
+edit docs/architecture/system/ADR-113-operator-proposed.md "s.replace('basis:\n', 'basis:\n  - evidence: a review fix\n', 1)"
+commit_all "review fix"
+(cd "$WORK/repo" && git switch -q - && git merge -q --no-ff -m "merge review" review)
+capture v1-frozen-merged-branch lint docs/architecture/system/ADR-113-operator-proposed.md
+edit docs/architecture/system/ADR-113-operator-proposed.md "s.replace('  - evidence: a review fix\n', '')"
+capture v1-frozen-merged-branch-edited lint docs/architecture/system/ADR-113-operator-proposed.md
+
 # A non-UTF-8 blob in a record's history does not stop lint.
 fresh v1
 printf 'binary \377\376 junk\n' > "$WORK/repo/docs/architecture/system/ADR-102-ingest-spec.md"

tests/fixtures/adr/golden/v1-frozen-merged-branch-edited.out

@@ -0,0 +1,20 @@
+
+Scanned: 1 ADRs
+
+Status distribution:
+  accepted: 1
+
+Contract: adr/v1 (1 v0 records remain)
+
+────────────────────────────────────────────────────────────
+Issues found in 1 files:
+────────────────────────────────────────────────────────────
+
+docs/architecture/system/ADR-113-operator-proposed.md
+  ❌ 'basis' changed after the decision left proposed; only concern, considered, enacted, status, superseded_by may change
+
+════════════════════════════════════════════════════════════
+Summary: 1 errors, 0 warnings
+════════════════════════════════════════════════════════════
+
+[exit 0]

tests/fixtures/adr/golden/v1-frozen-merged-branch.out

@@ -0,0 +1,13 @@
+
+Scanned: 1 ADRs
+
+Status distribution:
+  accepted: 1
+
+Contract: adr/v1 (1 v0 records remain)
+
+════════════════════════════════════════════════════════════
+Summary: 0 errors, 0 warnings
+════════════════════════════════════════════════════════════
+
+[exit 0]