feat(B-0170.4): seed convention-drift fixture + regression test

tools/substrate-claim-checker/fixtures.test.ts

@@ -12,6 +12,7 @@
 
 import { describe, expect, test } from "bun:test";
 import { join } from "node:path";
+import { checkFile as checkConvention } from "./check-convention.ts";
 import { checkFile as checkCounts } from "./check-counts.ts";
 import { checkFile as checkCrossSurface } from "./check-cross-surface.ts";
 import { checkFile as checkExistence } from "./check-existence.ts";
@@ -107,3 +108,28 @@ describe("eval-set fixtures / path-form drift", () => {
     ]);
   });
 });
+
+describe("eval-set fixtures / convention drift", () => {
+  test("convention-drift-no-reciprocal-marker.md — Supersedes-ADR claim with target lacking reciprocal '**Superseded by**' marker is detected", () => {
+    const result = checkConvention(join(fixtures, "convention-drift-no-reciprocal-marker.md"));
+    expect(result.ok).toBe(true);
+    // PR #3611 discipline applied to convention drift: pin exact
+    // finding count + claim line + target so a regression in either
+    // claim extraction or reciprocal-marker scanning cannot pass
+    // silently. The fixture pair is self-contained — the predecessor
+    // ADR support file lives as a sibling under fixtures/ so the
+    // 3-root resolution (fileDir / parentDir / repoRoot) finds it via
+    // fileDir without depending on any real repo ADR pair.
+    expect(result.findings.length).toBe(1);
+    const finding = result.findings[0]!;
+    // Body claim is on the line carrying `Supersedes ADR \`...\`` in
+    // the fixture; pinning the line catches regressions where the
+    // checker's logical-line scanner drifts off the physical line.
+    expect(finding.line).toBe(36);
+    expect(finding.target).toBe(
+      "tools/substrate-claim-checker/fixtures/_convention-drift-target-adr.md",
+    );
+    expect(finding.reason).toContain("not reciprocated");
+    expect(finding.reason).toContain("Superseded by");
+  });
+});

tools/substrate-claim-checker/fixtures/README.md

@@ -25,6 +25,7 @@ axis.
 | existence drift | `existence-drift-missing-doc.md` | PR #1252 — verify-then-claim memo body table instance #8 (`future-domain memo references docs/courier-ferry-protocol.md` / doesn't exist) | backtick-quoted synthetic path resolves at no candidate root |
 | path-form drift | `path-form-drift-bare-vs-qualified.md` | verify-then-claim memo **instance #15 / PR #1256** (adjacent ADR citations mixing fully-qualified with bare filename — path-form sub-class #6 of the 7-class list) — synthetic exemplar; instance #15's literal substance is captured in a follow-on fixture (B-0170.4.1) | same on-disk file referenced as both `check-counts.ts` and `tools/substrate-claim-checker/check-counts.ts` |
 | cross-surface count drift | `cross-surface-drift-9-vs-15.md` | verify-then-claim memo **instance #19** — YAML frontmatter `description:` (and MEMORY.md index in the historical case) claimed "9 drift instances" while the body table already held 15 rows; check-cross-surface "any-table" semantics fire when zero body tables match the claim | frontmatter description claims "9 drift instances" vs 15-row body table — one finding |
+| convention drift | `convention-drift-no-reciprocal-marker.md` (+ `_convention-drift-target-adr.md` support file) | PR #2512 (`feat(B-0170): add ADR supersession convention checker`) — synthetic exemplar covering the convention sub-class of the 7-class verify-then-claim taxonomy; the fixture pair makes the broken half of the bidirectional ADR convention reproducible without depending on any real ADR pair | "Supersedes ADR \`_convention-drift-target-adr.md\`" claim with target lacking the reciprocal "**Superseded by**" marker — one finding |
 
 Add a new row when a new fixture lands.
 

tools/substrate-claim-checker/fixtures/_convention-drift-target-adr.md

@@ -0,0 +1,24 @@
+<!--
+Eval-set fixture support file for substrate-claim-checker (B-0170.4).
+
+This is the "predecessor ADR" half of the convention-drift fixture pair.
+It is intentionally missing the top-of-file "**Superseded by**" marker
+that `check-convention.ts` looks for when validating reciprocal ADR
+supersession claims. The companion fixture
+`convention-drift-no-reciprocal-marker.md` claims to supersede this
+file; the absence of the reciprocal marker here is the convention
+drift the checker is expected to surface.
+
+The filename leads with `_` to signal "fixture support file, not a
+top-level fixture itself" — same shape convention as a leading-dot
+file but visible in `ls` output for review-thread legibility.
+-->
+
+# Predecessor ADR (fixture support file)
+
+**Status:** Accepted.
+
+## Decision
+
+Synthetic ADR body — content is not meaningful; only the absence of a
+"Superseded by" marker matters for the convention-drift fixture pair.

tools/substrate-claim-checker/fixtures/convention-drift-no-reciprocal-marker.md

@@ -0,0 +1,44 @@
+<!--
+Eval-set fixture for substrate-claim-checker (B-0170.4).
+
+Reproduces the convention-drift pattern check-convention.ts surfaces —
+a current ADR carries a "Supersedes ADR ..." claim but the predecessor
+ADR file lacks the reciprocal top-of-file "Superseded by" marker. The
+pair makes the broken half of the bidirectional ADR convention
+empirically reproducible without depending on any real ADR pair in
+the repo.
+
+This is the fifth eval-set fixture (after count-drift-9-vs-15.md,
+existence-drift-missing-doc.md, path-form-drift-bare-vs-qualified.md,
+and cross-surface-drift-9-vs-15.md), extending B-0170.4 regression
+coverage to the convention sub-class of the 7-class verify-then-claim
+taxonomy.
+
+Anchor PR: #2512 (`feat(B-0170): add ADR supersession convention
+checker`) — the PR that shipped the check-convention.ts checker.
+This fixture is a synthetic exemplar (no single historical drift
+instance anchors the sub-class), same shape as path-form-drift's
+synthetic exemplar.
+
+The predecessor ADR lives as a sibling support file
+`_convention-drift-target-adr.md` so check-convention.ts's 3-root
+resolution (fileDir / parentDir / repoRoot) finds it via the
+fileDir candidate without dragging in any real repo ADR.
+
+NOTE: per PR #3611 review-thread discipline, this HTML comment
+intentionally avoids restating the literal "Supersedes ADR ..."
+claim from the body so a regression in body-claim detection
+cannot be masked by a comment-side match.
+-->
+
+# Current ADR (eval-set fixture)
+
+**Status:** Accepted. Supersedes ADR `_convention-drift-target-adr.md`.
+
+## Decision
+
+Synthetic ADR body — the body's substance is not material to the
+fixture; only the supersession claim above matters. The predecessor
+ADR pointed at by that claim is intentionally missing the reciprocal
+"Superseded by" marker, which is the convention drift the checker
+must surface.