refactor(audit-ai-docs): DI execSync for warm-path probeR4 tests + testTimeout 120s ceiling

packages/core/audit-self/audit-ai-docs.test.ts

@@ -55,6 +55,25 @@ function writeFile(dir: string, relPath: string, content: string): string {
   return full;
 }
 
+/**
+ * Fast execSync stub for warm-path probeR4 tests (DN-1 Path C, 2026-05-25).
+ *
+ * Mirrors the subprocess outcomes probeR4 cares about without spawning npx:
+ *   - `npx --version` → returns '8.0.0\n' (npx is available)
+ *   - `npx --no-install tsx scripts/audit-r4.ts` → throws ENOENT (tsx not installed)
+ *
+ * These assertions exercise CONDITIONAL LOGIC (early-return branches), not
+ * real-subprocess contract. The :344 contract test deliberately omits this
+ * stub — semantic preservation is the design intent of Option C.
+ */
+const fastExecSyncStub = ((cmd: string): Buffer => {
+  if (cmd.startsWith('npx --version')) return Buffer.from('8.0.0\n');
+  // `npx --no-install tsx ...` → simulate tsx absent (real behaviour on warm-path test envs)
+  const err: NodeJS.ErrnoException = new Error('ENOENT: tsx not found');
+  err.code = 'ENOENT';
+  throw err;
+}) as unknown as typeof import('node:child_process').execSync;
+
 // ─── extractProseText() — remark code-fence-aware extraction ─────────────────
 
 describe('extractProseText()', () => {
@@ -1502,10 +1521,13 @@ describe('probeR4() — execSync call content (L160-171)', () => {
     // Only tsconfig present (no ts-morph) → condition !hasTsconfig && !hasTsMorph is false
     // LogicalOperator mutant !hasTsconfig || !hasTsMorph would be TRUE → early-return
     // So the mutant would produce 'warn' instead of 'fail'/'warn' from execSync
+    //
+    // Uses fastExecSyncStub (DN-1 Path C) — this test asserts on conditional logic,
+    // not on real-subprocess contract. The :344 sibling keeps real execSync.
     mkdirSync(join(dir, 'src/domain'), { recursive: true });
     writeFile(dir, 'src/domain/a.ts', 'export const x = 1;\n');
     writeFile(dir, 'tsconfig.json', '{"compilerOptions":{}}\n');
-    const result = probeR4(dir);
+    const result = probeR4(dir, { execSync: fastExecSyncStub });
     // hasTsconfig=true → condition !hasTsconfig && !hasTsMorph = false → does NOT early-return
     // → execSync runs → result is fail or warn (from execSync failure)
     expect(['warn', 'fail']).toContain(result.result);
@@ -1522,12 +1544,14 @@ describe('probeR4() — execSync call content (L160-171)', () => {
     // With || mutant: !hasTsconfig || !hasTsMorph → if only hasTsMorph is true (hasTsconfig=false)
     // → condition is true → early-return warn (wrong!)
     // Real code: !hasTsconfig && !hasTsMorph → false when either is present
+    //
+    // Uses fastExecSyncStub (DN-1 Path C) — see sibling test above for rationale.
     mkdirSync(join(dir, 'src/domain'), { recursive: true });
     writeFile(dir, 'src/domain/a.ts', 'export const x = 1;\n');
     // Make ts-morph "present" via the existence check
     mkdirSync(join(dir, 'node_modules/ts-morph'), { recursive: true });
     writeFile(dir, 'node_modules/ts-morph/package.json', '{"name":"ts-morph"}\n');
-    const result = probeR4(dir);
+    const result = probeR4(dir, { execSync: fastExecSyncStub });
     // hasTsMorph=true → !hasTsconfig && !hasTsMorph = false → does NOT early-return
     // The result should be 'fail' or 'warn' (execSync fails, not the early-return warn)
     expect(['warn', 'fail']).toContain(result.result);

packages/core/audit-self/audit-ai-docs.ts

@@ -151,14 +151,23 @@ export function extractDeclaredSkills(agentsMarkdown: string): string[] {
  * R4 probe: every domain export in src/domain has a matching .unit.ts file.
  * Delegates to `scripts/audit-r4.ts` in the consumer project via npx tsx.
  * Falls back to WARN(skipped) when env lacks Node/tsx/tsconfig.
+ *
+ * `opts.execSync` is the dependency-injection seam for warm-path tests
+ * (DN-1 Path C, 2026-05-25); omit it in prod and contract tests — defaults
+ * to the real `execSync` from node:child_process, preserving byte-for-byte
+ * subprocess behaviour.
  */
-export function probeR4(cwd: string): { result: 'pass' | 'fail' | 'warn'; message: string } {
+export function probeR4(
+  cwd: string,
+  opts?: { execSync?: typeof execSync },
+): { result: 'pass' | 'fail' | 'warn'; message: string } {
+  const exec = opts?.execSync ?? execSync;
   const RULE = 'R4: Every public export in src/domain has matching .unit.ts (ts-morph)';
   if (!existsSync(join(cwd, 'src/domain'))) {
     return { result: 'pass', message: `${RULE} (skipped: no src/domain)` };
   }
   try {
-    execSync('npx --version', { stdio: 'ignore' });
+    exec('npx --version', { stdio: 'ignore' });
   } catch {
     return { result: 'warn', message: `${RULE} (skipped: npx not found)` };
   }
@@ -168,7 +177,7 @@ export function probeR4(cwd: string): { result: 'pass' | 'fail' | 'warn'; messag
     return { result: 'warn', message: `${RULE} (skipped: no tsconfig.json and ts-morph not installed)` };
   }
   try {
-    execSync('npx --no-install tsx scripts/audit-r4.ts', { cwd, stdio: 'pipe' });
+    exec('npx --no-install tsx scripts/audit-r4.ts', { cwd, stdio: 'pipe' });
     return { result: 'pass', message: RULE };
   } catch {
     return { result: 'fail', message: RULE };

vitest.config.ts

@@ -16,6 +16,9 @@
 // worktrees scope. testTimeout covers cold npm cache + slow connection in
 // audit-ai-docs.test.ts:344 (local measurement ~24s; 60s = safe margin).
 // Longer-term fix: see .claude/orchestrator-prompts/slow-test-triage/.
+//
+// Ceiling: testTimeout MUST NOT exceed 120_000 without a paired slow-test-triage R-phase.
+// Further bumps require fixing the slow path, not raising the lid (DN-3 Option A, 2026-05-25).
 
 export default {
   test: {