fix(cli): list installed extensions when update target missing (#17082)

packages/cli/src/commands/extensions/update.test.ts

@@ -24,6 +24,7 @@ import { ExtensionUpdateState } from '../../ui/state/extensions.js';
 
 // Mock dependencies
 const emitConsoleLog = vi.hoisted(() => vi.fn());
+const emitFeedback = vi.hoisted(() => vi.fn());
 const debugLogger = vi.hoisted(() => ({
   log: vi.fn((message, ...args) => {
     emitConsoleLog('log', format(message, ...args));
@@ -40,6 +41,7 @@ vi.mock('@google/gemini-cli-core', async (importOriginal) => {
     ...actual,
     coreEvents: {
       emitConsoleLog,
+      emitFeedback,
     },
     debugLogger,
   };
@@ -84,6 +86,42 @@ describe('extensions update command', () => {
   });
 
   describe('handleUpdate', () => {
+    it('should list installed extensions when requested extension is not found', async () => {
+      const mockCwd = vi.spyOn(process, 'cwd').mockReturnValue('/test/dir');
+      const extensions = [
+        { name: 'ext1', version: '1.0.0' },
+        { name: 'ext2', version: '2.0.0' },
+      ];
+      mockExtensionManager.prototype.loadExtensions = vi
+        .fn()
+        .mockResolvedValue(extensions);
+
+      await handleUpdate({ name: 'missing-extension' });
+
+      expect(emitFeedback).toHaveBeenCalledWith(
+        'error',
+        'Extension "missing-extension" not found.\n\nInstalled extensions:\next1 (1.0.0)\next2 (2.0.0)\n\nRun "gemini extensions list" for details.',
+      );
+      expect(mockUpdateExtension).not.toHaveBeenCalled();
+      mockCwd.mockRestore();
+    });
+
+    it('should log a helpful message when no extensions are installed and requested extension is not found', async () => {
+      const mockCwd = vi.spyOn(process, 'cwd').mockReturnValue('/test/dir');
+      mockExtensionManager.prototype.loadExtensions = vi
+        .fn()
+        .mockResolvedValue([]);
+
+      await handleUpdate({ name: 'missing-extension' });
+
+      expect(emitFeedback).toHaveBeenCalledWith(
+        'error',
+        'Extension "missing-extension" not found.\n\nNo extensions installed.',
+      );
+      expect(mockUpdateExtension).not.toHaveBeenCalled();
+      mockCwd.mockRestore();
+    });
+
     it.each([
       {
         state: ExtensionUpdateState.UPDATE_AVAILABLE,

packages/cli/src/commands/extensions/update.ts

@@ -14,7 +14,7 @@ import {
 import { checkForExtensionUpdate } from '../../config/extensions/github.js';
 import { getErrorMessage } from '../../utils/errors.js';
 import { ExtensionUpdateState } from '../../ui/state/extensions.js';
-import { debugLogger } from '@google/gemini-cli-core';
+import { coreEvents, debugLogger } from '@google/gemini-cli-core';
 import { ExtensionManager } from '../../config/extension-manager.js';
 import { requestConsentNonInteractive } from '../../config/extensions/consent.js';
 import { loadSettings } from '../../config/settings.js';
@@ -46,7 +46,21 @@ export async function handleUpdate(args: UpdateArgs) {
         (extension) => extension.name === args.name,
       );
       if (!extension) {
-        debugLogger.log(`Extension "${args.name}" not found.`);
+        if (extensions.length === 0) {
+          coreEvents.emitFeedback(
+            'error',
+            `Extension "${args.name}" not found.\n\nNo extensions installed.`,
+          );
+          return;
+        }
+
+        const installedExtensions = extensions
+          .map((extension) => `${extension.name} (${extension.version})`)
+          .join('\n');
+        coreEvents.emitFeedback(
+          'error',
+          `Extension "${args.name}" not found.\n\nInstalled extensions:\n${installedExtensions}\n\nRun "gemini extensions list" for details.`,
+        );
         return;
       }
       if (!extension.installMetadata) {
@@ -63,7 +77,6 @@ export async function handleUpdate(args: UpdateArgs) {
         debugLogger.log(`Extension "${args.name}" is already up to date.`);
         return;
       }
-      // TODO(chrstnb): we should list extensions if the requested extension is not installed.
       const updatedExtensionInfo = (await updateExtension(
         extension,
         extensionManager,