fix(files): handle reveal launcher failures (#2490)

packages/web/server/lib/fs/routes.js

@@ -382,6 +382,7 @@ export const registerFsRoutes = (app, dependencies) => {
     path,
     fsPromises,
     spawn,
+    platform = process.platform,
     crypto,
     normalizeDirectoryPath,
     resolveProjectDirectory,
@@ -393,6 +394,27 @@ export const registerFsRoutes = (app, dependencies) => {
     realpath: fsPromises.realpath.bind(fsPromises),
   });
 
+  const spawnDetached = (command, args) => new Promise((resolve, reject) => {
+    let child;
+    try {
+      child = spawn(command, args, { windowsHide: true, stdio: 'ignore', detached: true });
+    } catch (error) {
+      reject(new Error('Failed to launch file browser', { cause: error }));
+      return;
+    }
+    const onError = (error) => {
+      child.removeListener('spawn', onSpawn);
+      reject(new Error('Failed to launch file browser', { cause: error }));
+    };
+    const onSpawn = () => {
+      child.removeListener('error', onError);
+      child.unref();
+      resolve();
+    };
+    child.once('error', onError);
+    child.once('spawn', onSpawn);
+  });
+
   const execJobs = new Map();
   const commandTimeoutMs = createCommandTimeoutMs();
   const gitReadCacheTtlMs = createGitReadCacheTtlMs();
@@ -1134,13 +1156,12 @@ export const registerFsRoutes = (app, dependencies) => {
       const resolved = path.resolve(targetPath.trim());
       await fsPromises.access(resolved);
 
-      const platform = process.platform;
       if (platform === 'darwin') {
         const stat = await fsPromises.stat(resolved);
         if (stat.isDirectory()) {
-          spawn('open', [resolved], { windowsHide: true, stdio: 'ignore', detached: true }).unref();
+          await spawnDetached('open', [resolved]);
         } else {
-          spawn('open', ['-R', resolved], { windowsHide: true, stdio: 'ignore', detached: true }).unref();
+          await spawnDetached('open', ['-R', resolved]);
         }
       } else if (platform === 'win32') {
         const stat = await fsPromises.stat(resolved);
@@ -1164,7 +1185,7 @@ export const registerFsRoutes = (app, dependencies) => {
       } else {
         const stat = await fsPromises.stat(resolved);
         const dir = stat.isDirectory() ? resolved : path.dirname(resolved);
-        spawn('xdg-open', [dir], { windowsHide: true, stdio: 'ignore', detached: true }).unref();
+        await spawnDetached('xdg-open', [dir]);
       }
 
       return res.json({ success: true, path: resolved });

packages/web/server/lib/fs/routes.test.js

@@ -200,6 +200,27 @@ const registerMkdir = (fsPromises) => {
   return getRoute('POST', '/api/fs/mkdir');
 };
 
+const registerReveal = ({ fsPromises, spawn, platform = 'linux' }) => {
+  const { app, getRoute } = createRouteRegistry();
+  registerFsRoutes(app, {
+    os: { homedir: () => '/home/user' },
+    path: path.posix,
+    fsPromises: {
+      realpath: async (targetPath) => targetPath,
+      ...fsPromises,
+    },
+    spawn,
+    platform,
+    crypto: { randomUUID: () => 'job-0' },
+    normalizeDirectoryPath: (p) => p,
+    resolveProjectDirectory: async () => ({ directory: '/repo' }),
+    buildAugmentedPath: () => '/usr/bin',
+    resolveGitBinaryForSpawn: () => 'git',
+    openchamberUserConfigRoot: '/home/user/.config',
+  });
+  return getRoute('POST', '/api/fs/reveal');
+};
+
 const callExec = async (handler, body) => {
   const res = createMockResponse();
   await handler({ body }, res);
@@ -230,6 +251,12 @@ const callMkdir = async (handler, body) => {
   return res;
 };
 
+const callReveal = async (handler, body) => {
+  const res = createMockResponse();
+  await handler({ body }, res);
+  return res;
+};
+
 describe('fs write', () => {
   it('does not rewrite a file when content is unchanged', async () => {
     const fsPromises = {
@@ -431,6 +458,77 @@ describe('fs read', () => {
   });
 });
 
+describe('fs reveal', () => {
+  it.each([
+    ['linux', 'xdg-open', ['/repo']],
+    ['darwin', 'open', ['-R', '/repo/file.txt']],
+  ])('returns a controlled error when the %s launcher is unavailable', async (platform, command, args) => {
+    const error = vi.spyOn(console, 'error').mockImplementation(() => {});
+    const child = new EventEmitter();
+    child.unref = vi.fn();
+    const spawn = vi.fn(() => {
+      queueMicrotask(() => child.emit('error', Object.assign(new Error('not found'), { code: 'ENOENT' })));
+      return child;
+    });
+    const handler = registerReveal({
+      fsPromises: {
+        access: vi.fn(async () => undefined),
+        stat: vi.fn(async () => ({ isDirectory: () => false })),
+      },
+      spawn,
+      platform,
+    });
+
+    const res = await callReveal(handler, { path: '/repo/file.txt' });
+
+    expect(res.statusCode).toBe(500);
+    expect(res.body).toEqual({ error: 'Failed to launch file browser' });
+    expect(spawn).toHaveBeenCalledWith(command, args, { windowsHide: true, stdio: 'ignore', detached: true });
+    expect(child.unref).not.toHaveBeenCalled();
+    error.mockRestore();
+  });
+
+  it('unrefs a detached launcher only after it spawns successfully', async () => {
+    const child = new EventEmitter();
+    child.unref = vi.fn();
+    const spawn = vi.fn(() => {
+      queueMicrotask(() => child.emit('spawn'));
+      return child;
+    });
+    const handler = registerReveal({
+      fsPromises: {
+        access: vi.fn(async () => undefined),
+        stat: vi.fn(async () => ({ isDirectory: () => false })),
+      },
+      spawn,
+    });
+
+    const res = await callReveal(handler, { path: '/repo/file.txt' });
+
+    expect(res.body).toEqual({ success: true, path: '/repo/file.txt' });
+    expect(child.unref).toHaveBeenCalledOnce();
+  });
+
+  it('returns a controlled error when the launcher throws synchronously', async () => {
+    const error = vi.spyOn(console, 'error').mockImplementation(() => {});
+    const spawnError = Object.assign(new Error('not found'), { code: 'ENOENT' });
+    const handler = registerReveal({
+      fsPromises: {
+        access: vi.fn(async () => undefined),
+        stat: vi.fn(async () => ({ isDirectory: () => false })),
+      },
+      spawn: vi.fn(() => { throw spawnError; }),
+    });
+
+    const res = await callReveal(handler, { path: '/repo/file.txt' });
+
+    expect(res.statusCode).toBe(500);
+    expect(res.body).toEqual({ error: 'Failed to launch file browser' });
+    expect(error).toHaveBeenCalledWith('Failed to reveal path:', expect.objectContaining({ cause: spawnError }));
+    error.mockRestore();
+  });
+});
+
 describe('fs exec git-read cache', () => {
   beforeEach(() => {
     delete process.env.OPENCHAMBER_GIT_READ_CACHE_TTL_MS;