fix(core): keep the no-follow helper mockable by fs spy suites

openSyncNoFollow bound node:fs through a namespace import, which vitest resolves to its own copy of the externalized CJS module. Suites that spy the fs object — sessionService.rename.test.ts stubs openSync/readSync for fabricated session paths — never intercept that copy, so the open threw on the mocked paths and the catch-all reported "no title" (10 of 19 tests red, the CI Test failure). Take the fs binding through the default import the way the callers' suites spy it, teach the doMock factories to carry the stub on the default binding too, and stub lstatSync/fstatSync in the rename suite so the Windows lstat -> open -> fstat fallback accepts the fabricated paths as well. Co-authored-by: Qwen-Coder <qwen-coder @alibabacloud.com>
wenshao · Aug 31, 2026 · Aug 25, 2026 · Aug 25, 2026 · Aug 25, 2026 · Aug 25, 2026
commit bdecd4c8534ea1ce7d9d8c37c4fd8c88aa306c20
@@ -83,6 +83,32 @@ describe('SessionService - rename and custom title', () => {
     vi.spyOn(fs, 'openSync').mockReturnValue(42);
     readSyncSpy = vi.spyOn(fs, 'readSync').mockReturnValue(0);
     vi.spyOn(fs, 'closeSync').mockImplementation(() => undefined);
+    // Platforms without O_NOFOLLOW (Windows) open session files through an
+    // lstat -> open -> fstat identity check (openSyncNoFollow). Spy both
+    // stats so that fallback accepts the fabricated paths above: a regular
+    // (non-symlink) file whose identity trivially matches itself. On
+    // platforms with the flag the spies stay inert.
+    vi.spyOn(fs, 'lstatSync').mockImplementation(
+      () =>
+        ({
+          dev: 1,
+          ino: 1,
+          isSymbolicLink: () => false,
+          isFile: () => true,
+        }) as unknown as fs.Stats,
+    );
+    vi.spyOn(fs, 'fstatSync').mockImplementation(
+      () =>
+        ({
+          dev: 1,
+          ino: 1,
+          // size 0 keeps readLatestTailIfGrown's grown-tail pass inert,
+          // matching the pre-rerouting behavior where it never ran.
+          size: 0,
+          isSymbolicLink: () => false,
+          isFile: () => true,
+        }) as unknown as fs.Stats,
+    );
 
     vi.mocked(jsonl.read).mockResolvedValue([]);
     vi.mocked(jsonl.readLines).mockResolvedValue([]);

@@ -108,10 +108,14 @@ describe('openNoFollow without O_NOFOLLOW (Windows flag set)', () => {
     vi.resetModules();
     vi.doMock('node:fs', async (importOriginal) => {
       const actual = await importOriginal<typeof import('node:fs')>();
-      return {
+      // The helper uses a DEFAULT import of node:fs, so the `default`
+      // property must carry the stubbed constants too (`...actual` alone
+      // would keep the real default binding with the real O_NOFOLLOW).
+      const modified = {
         ...actual,
         constants: { ...actual.constants, O_NOFOLLOW: undefined },
       };
+      return { ...modified, default: modified };
     });
     const mockedFs = await import('node:fs');
     const { openNoFollow: openFallback, openSyncNoFollow: openSyncFallback } =
@@ -172,7 +176,7 @@ describe('openNoFollow without O_NOFOLLOW (Windows flag set)', () => {
       vi.resetModules();
       vi.doMock('node:fs', async (importOriginal) => {
         const actual = await importOriginal<typeof import('node:fs')>();
-        return {
+        const modified = {
           ...actual,
           constants: { ...actual.constants, O_NOFOLLOW: undefined },
           fstatSync: ((fd: number) => {
@@ -184,6 +188,7 @@ describe('openNoFollow without O_NOFOLLOW (Windows flag set)', () => {
             );
           }) as typeof actual.fstatSync,
         };
+        return { ...modified, default: modified };
       });
 
       try {
@@ -210,7 +215,7 @@ describe('openNoFollow without O_NOFOLLOW (Windows flag set)', () => {
     vi.resetModules();
     vi.doMock('node:fs', async (importOriginal) => {
       const actual = await importOriginal<typeof import('node:fs')>();
-      return {
+      const modified = {
         ...actual,
         constants: { ...actual.constants, O_NOFOLLOW: undefined },
         lstatSync: ((p: string) => {
@@ -222,6 +227,7 @@ describe('openNoFollow without O_NOFOLLOW (Windows flag set)', () => {
           );
         }) as typeof actual.lstatSync,
       };
+      return { ...modified, default: modified };
     });
 
     try {

@@ -32,9 +32,15 @@
  * Every refusal is reported as an error with `code: 'ELOOP'` — the same
  * code POSIX `O_NOFOLLOW` produces — so existing `ELOOP` handling in
  * callers applies to the fallback path unchanged.
+ *
+ * `node:fs` is bound through the DEFAULT import (not a namespace import)
+ * so suites that spy the fs object — the way `sessionService.rename.test.ts`
+ * spies `openSync`/`readSync` for its fabricated session paths — intercept
+ * this helper's calls too: vitest hands namespace imports their own copy of
+ * an externalized CJS module, which escapes those spies (#8227).
  */
 
-import * as fs from 'node:fs';
+import fs from 'node:fs';
 import type { FileHandle } from 'node:fs/promises';
 
 import { hasVerifiableInode } from './file-identity.js';