test: add tsconfig walk-up, compact fallback, and Windows atomic write tests (Round 56)

tests/hooks/hooks.test.js

@@ -2811,6 +2811,51 @@ async function runTests() {
     }
   })) passed++; else failed++;
 
+  // ── Round 56: typecheck tsconfig walk-up, suggest-compact fallback path ──
+  console.log('\nRound 56: post-edit-typecheck.js (tsconfig in parent directory):');
+
+  if (await asyncTest('walks up directory tree to find tsconfig.json in grandparent', async () => {
+    const testDir = createTestDir();
+    // Place tsconfig at the TOP level, file is nested 2 levels deep
+    fs.writeFileSync(path.join(testDir, 'tsconfig.json'), JSON.stringify({
+      compilerOptions: { strict: false, noEmit: true }
+    }));
+    const deepDir = path.join(testDir, 'src', 'components');
+    fs.mkdirSync(deepDir, { recursive: true });
+    const testFile = path.join(deepDir, 'widget.ts');
+    fs.writeFileSync(testFile, 'export const value: number = 42;\n');
+
+    const stdinJson = JSON.stringify({ tool_input: { file_path: testFile } });
+    const result = await runScript(path.join(scriptsDir, 'post-edit-typecheck.js'), stdinJson);
+
+    assert.strictEqual(result.code, 0, 'Should exit 0 after walking up to find tsconfig');
+    // Core assertion: stdin must pass through regardless of whether tsc ran
+    const parsed = JSON.parse(result.stdout);
+    assert.strictEqual(parsed.tool_input.file_path, testFile,
+      'Should pass through original stdin data with file_path intact');
+    cleanupTestDir(testDir);
+  })) passed++; else failed++;
+
+  console.log('\nRound 56: suggest-compact.js (counter file as directory — fallback path):');
+
+  if (await asyncTest('exits 0 when counter file path is occupied by a directory', async () => {
+    const sessionId = `dirblock-${Date.now()}`;
+    const counterFile = path.join(os.tmpdir(), `claude-tool-count-${sessionId}`);
+    // Create a DIRECTORY at the counter file path — openSync('a+') will fail with EISDIR
+    fs.mkdirSync(counterFile);
+
+    try {
+      const result = await runScript(path.join(scriptsDir, 'suggest-compact.js'), '', {
+        CLAUDE_SESSION_ID: sessionId
+      });
+      assert.strictEqual(result.code, 0,
+        'Should exit 0 even when counter file path is a directory (graceful fallback)');
+    } finally {
+      // Cleanup: remove the blocking directory
+      try { fs.rmdirSync(counterFile); } catch { /* best-effort */ }
+    }
+  })) passed++; else failed++;
+
   // Summary
   console.log('\n=== Test Results ===');
   console.log(`Passed: ${passed}`);

tests/lib/session-aliases.test.js

@@ -856,6 +856,46 @@ function runTests() {
     assert.strictEqual(data.metadata.totalCount, 5, 'Metadata count should match actual aliases');
   })) passed++; else failed++;
 
+  // ── Round 56: Windows platform unlink-before-rename code path ──
+  console.log('\nRound 56: Windows platform atomic write path:');
+
+  if (test('Windows platform mock: unlinks existing file before rename', () => {
+    resetAliases();
+    // First create an alias so the file exists
+    const r1 = aliases.setAlias('win-initial', '2026-01-01-abc123-session.tmp');
+    assert.strictEqual(r1.success, true, 'Initial alias should succeed');
+    const aliasesPath = aliases.getAliasesPath();
+    assert.ok(fs.existsSync(aliasesPath), 'Aliases file should exist before win32 test');
+
+    // Mock process.platform to 'win32' to trigger the unlink-before-rename path
+    const origPlatform = Object.getOwnPropertyDescriptor(process, 'platform');
+    Object.defineProperty(process, 'platform', { value: 'win32', configurable: true });
+
+    try {
+      // This save triggers the Windows code path: unlink existing → rename temp
+      const r2 = aliases.setAlias('win-updated', '2026-02-01-def456-session.tmp');
+      assert.strictEqual(r2.success, true, 'setAlias should succeed under win32 mock');
+
+      // Verify data integrity after the Windows path
+      assert.ok(fs.existsSync(aliasesPath), 'Aliases file should exist after win32 save');
+      const data = aliases.loadAliases();
+      assert.ok(data.aliases['win-initial'], 'Original alias should still exist');
+      assert.ok(data.aliases['win-updated'], 'New alias should exist');
+      assert.strictEqual(data.aliases['win-updated'].sessionPath,
+        '2026-02-01-def456-session.tmp', 'Session path should match');
+
+      // No .tmp or .bak files left behind
+      assert.ok(!fs.existsSync(aliasesPath + '.tmp'), 'No temp file should remain');
+      assert.ok(!fs.existsSync(aliasesPath + '.bak'), 'No backup file should remain');
+    } finally {
+      // Restore original platform descriptor
+      if (origPlatform) {
+        Object.defineProperty(process, 'platform', origPlatform);
+      }
+      resetAliases();
+    }
+  })) passed++; else failed++;
+
   // Summary
   console.log(`\nResults: Passed: ${passed}, Failed: ${failed}`);
   process.exit(failed > 0 ? 1 : 0);