fix: add regression-test-presence gate + missing tests for #2429/#2279 (#2563)

lint-fix-has-regression-test.cjs: new gate that fails if a fix(#NNNN)
or feat(#NNNN) commit has zero behavioral test files (*.test.cjs,
excluding auto-generated fixtures/baselines) in its diff. Wired into
lint:ci so it runs before PR creation.

Missing regression tests added:
- #2429: codex local scope does not set $HOME/.agents skills home;
  global scope does (tests/runtime-artifact-layout.test.cjs)
- #2279: map-codebase instructions say to overwrite existing dates,
  not just replace [YYYY-MM-DD] placeholders (tests/commands.test.cjs)

package.json

@@ -103,7 +103,7 @@
     "lint": "eslint . --cache --cache-location node_modules/.cache/eslint/",
     "lint:fix": "eslint . --fix",
     "lint:table-schema-drift": "node scripts/lint-table-schema-drift.cjs",
-    "lint:ci": "npm run lint && npm run lint:skill-deps && npm run lint:generated-sync && node scripts/lint-test-file-count.cjs && node scripts/lint-command-contract.cjs && node scripts/lint-pr-check-project-dir.cjs && npm run lint:legacy-name && node scripts/lint-regression-test-names.cjs && node scripts/lint-allow-test-rule-refs.cjs && node scripts/lint-resolution-provenance.cjs && node scripts/lint-portable-timeout.cjs && node scripts/validate-registry.cjs && node scripts/lint-table-schema-drift.cjs",
+    "lint:ci": "npm run lint && npm run lint:skill-deps && npm run lint:generated-sync && node scripts/lint-test-file-count.cjs && node scripts/lint-command-contract.cjs && node scripts/lint-pr-check-project-dir.cjs && npm run lint:legacy-name && node scripts/lint-regression-test-names.cjs && node scripts/lint-allow-test-rule-refs.cjs && node scripts/lint-resolution-provenance.cjs && node scripts/lint-portable-timeout.cjs && node scripts/validate-registry.cjs && node scripts/lint-table-schema-drift.cjs && node scripts/lint-fix-has-regression-test.cjs",
     "lint:allow-test-rule-refs": "node scripts/lint-allow-test-rule-refs.cjs",
     "lint:regression-names": "node scripts/lint-regression-test-names.cjs",
     "lint:descriptions": "node scripts/lint-descriptions.cjs",

scripts/lint-fix-has-regression-test.cjs

@@ -0,0 +1,131 @@
+#!/usr/bin/env node
+'use strict';
+
+/**
+ * lint-fix-has-regression-test.cjs — gate: every fix(#NNNN) commit must
+ * include at least one behavioral test file (tests/*.test.cjs) that is NOT
+ * an auto-generated fixture/baseline.
+ *
+ * ## Why
+ *
+ * CONTRIBUTING.md:47: "Fix it. Write a test that would have caught the bug."
+ * CLAUDE.md: "Regression Protocol: Write the regression test first."
+ *
+ * Three merged PRs shipped without regression tests because the golden-fixture
+ * regeneration (20+ files under tests/) camouflaged the absence of real
+ * *.test.cjs changes. This gate makes the rule machine-enforced.
+ *
+ * ## What this enforces
+ *
+ * For every commit in `git log origin/next..HEAD` whose subject matches
+ * /^fix\(#\d+\)/ or /^feat\(#\d+\)/, the cumulative diff must include at
+ * least one file under tests/ matching /\.test\.cjs$/ that is NOT:
+ *   - under tests/fixtures/
+ *   - under tests/install-tree/
+ *   - a *-baseline.json file
+ *
+ * If the filtered list is empty, the gate fails with a message naming the
+ * fix commits and directing the author to add a regression test.
+ *
+ * ## Overrides
+ *
+ * Set GSD_SKIP_REGRESSION_TEST_GATE=1 for legitimate exceptions (e.g. a
+ * pure-config or pure-refactor PR where no behavioral test is possible).
+ * This env var is auditable in CI logs.
+ */
+
+const { execSync } = require('child_process');
+const { ExitError, runMain } = require('./lib/cli-exit.cjs');
+
+const FIX_OR_FEAT_RE = /^(?:fix|feat)\(#(\d+)\)/;
+
+const EXCLUDE_PATTERNS = [
+  /tests[\\/]fixtures[\\/]/,
+  /tests[\\/]install-tree[\\/]/,
+  /-baseline\.json$/,
+];
+
+function isRealTestFile(filePath) {
+  if (!filePath.includes('tests/')) return false;
+  if (!/\.test\.cjs$/.test(filePath)) return false;
+  return !EXCLUDE_PATTERNS.some((re) => re.test(filePath));
+}
+
+function getFixCommits(baseRef) {
+  const log = execSync(
+    `git log ${baseRef}..HEAD --format='%H%x09%s' --no-merges`,
+    { encoding: 'utf8', timeout: 10000 },
+  );
+  return log
+    .trim()
+    .split('\n')
+    .filter(Boolean)
+    .map((line) => {
+      const [sha, subject] = line.split('\t');
+      const match = subject.match(FIX_OR_FEAT_RE);
+      return match ? { sha: sha.slice(0, 12), subject, issue: match[1] } : null;
+    })
+    .filter(Boolean);
+}
+
+function getChangedTestFiles(baseRef) {
+  const diff = execSync(
+    `git diff ${baseRef}...HEAD --name-only --no-merges`,
+    { encoding: 'utf8', timeout: 10000 },
+  );
+  return diff
+    .trim()
+    .split('\n')
+    .filter(Boolean)
+    .filter(isRealTestFile);
+}
+
+function main() {
+  if (process.env.GSD_SKIP_REGRESSION_TEST_GATE === '1') {
+    console.log('lint-fix-has-regression-test: SKIPPED (GSD_SKIP_REGRESSION_TEST_GATE=1)');
+    return;
+  }
+
+  const baseRef = process.env.GSD_REGRESSION_GATE_BASE || 'origin/next';
+
+  let fixCommits;
+  try {
+    fixCommits = getFixCommits(baseRef);
+  } catch {
+    console.log(`lint-fix-has-regression-test: no fix/feat commits found vs ${baseRef}, skipping`);
+    return;
+  }
+
+  if (fixCommits.length === 0) {
+    console.log('lint-fix-has-regression-test: no fix/feat commits, passing');
+    return;
+  }
+
+  let testFiles;
+  try {
+    testFiles = getChangedTestFiles(baseRef);
+  } catch {
+    testFiles = [];
+  }
+
+  if (testFiles.length === 0) {
+    const commitList = fixCommits
+      .map((c) => `  ${c.sha} ${c.subject}`)
+      .join('\n');
+    throw new ExitError(1,
+      `lint-fix-has-regression-test: ${fixCommits.length} fix/feat commit(s) but ZERO behavioral test files (*.test.cjs) in the diff.\n` +
+      `Auto-generated fixtures (tests/fixtures/, *-baseline.json) do NOT count.\n\n` +
+      `Fix commits:\n${commitList}\n\n` +
+      `CONTRIBUTING.md:47: "Write a test that would have caught the bug."\n` +
+      `Add a regression test to an existing tests/*.test.cjs file, or set ` +
+      `GSD_SKIP_REGRESSION_TEST_GATE=1 if no behavioral test is possible (auditable in CI).`
+    );
+  }
+
+  console.log(
+    `lint-fix-has-regression-test: PASS — ${fixCommits.length} fix/feat commit(s), ` +
+    `${testFiles.length} behavioral test file(s): ${testFiles.join(', ')}`
+  );
+}
+
+runMain(main);

tests/commands.test.cjs

@@ -3585,3 +3585,33 @@ describe('query commit --files scoping (#2269)', () => {
     assert.match(content.slice(idx, idx + 200), /ROADMAP\.md/);
   });
 });
+
+describe('#2279: map-codebase date stamp instructions overwrite existing dates', () => {
+  const REPO_ROOT = path.join(__dirname, '..');
+
+  test('codebase-mapper agent says to SET date stamps, overwriting existing values', () => {
+    const content = fs.readFileSync(
+      path.join(REPO_ROOT, 'agents', 'gsd-codebase-mapper.md'), 'utf-8'
+    );
+    assert.match(content, /overwriting whatever date is already there/i,
+      'must instruct the agent to SET date stamps unconditionally, not just replace [YYYY-MM-DD] placeholders');
+  });
+
+  test('map-codebase workflow spawn prompts say to SET date stamps, not replace placeholders', () => {
+    const content = fs.readFileSync(
+      path.join(REPO_ROOT, 'gsd-core', 'workflows', 'map-codebase.md'), 'utf-8'
+    );
+    const stampLines = content.match(/Set all date stamps[^\r\n]*/g) || [];
+    assert.ok(stampLines.length >= 4,
+      `must have ≥4 "Set all date stamps" instructions (4 spawn prompts + 1 sequential); got ${stampLines.length}`);
+  });
+
+  test('map-codebase sequential path says to SET date stamps overwriting existing dates', () => {
+    const content = fs.readFileSync(
+      path.join(REPO_ROOT, 'gsd-core', 'workflows', 'map-codebase.md'), 'utf-8'
+    );
+    const idx = content.indexOf('overwriting any existing date');
+    assert.notEqual(idx, -1,
+      'workflow must instruct agents to overwrite existing dates, not just replace [YYYY-MM-DD] placeholders');
+  });
+});

tests/runtime-artifact-layout.test.cjs

@@ -101,6 +101,24 @@ describe('resolveRuntimeArtifactLayout — codex', () => {
     assert.strictEqual(layout.kinds[0].prefix, 'gsd-');
     assert.strictEqual(typeof layout.kinds[0].stage, 'function');
   });
+
+  test('#2429: codex local scope does not set $HOME/.agents skills home override', () => {
+    const layout = resolveRuntimeArtifactLayout('codex', FAKE_DIR, 'local');
+    const skills = layout.kinds.find(k => k.kind === 'skills');
+    assert.ok(skills, 'codex local must have a skills kind');
+    assert.strictEqual(skills.home, undefined,
+      'codex local skills must NOT have a home override (would redirect to $HOME/.agents instead of project-local)');
+  });
+
+  test('#2429: codex global scope DOES set $HOME/.agents skills home override', () => {
+    const layout = resolveRuntimeArtifactLayout('codex', FAKE_DIR, 'global');
+    const skills = layout.kinds.find(k => k.kind === 'skills');
+    assert.ok(skills, 'codex global must have a skills kind');
+    assert.ok(typeof skills.home === 'string' && skills.home.length > 0,
+      'codex global skills MUST have a home override ($HOME/.agents)');
+    assert.ok(skills.home.includes('.agents'),
+      'codex global skills home should point to .agents directory');
+  });
 });
 
 describe('resolveRuntimeArtifactLayout — copilot', () => {