fix(cli): resolve environment loading and auth validation issues in ACP mode (#18025)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/cli/src/zed-integration/zedIntegration.test.ts

@@ -26,7 +26,11 @@ import {
   type Config,
   type MessageBus,
 } from '@google/gemini-cli-core';
-import { SettingScope, type LoadedSettings } from '../config/settings.js';
+import {
+  SettingScope,
+  type LoadedSettings,
+  loadSettings,
+} from '../config/settings.js';
 import { loadCliConfig, type CliArgs } from '../config/config.js';
 import * as fs from 'node:fs/promises';
 import * as path from 'node:path';
@@ -35,6 +39,14 @@ vi.mock('../config/config.js', () => ({
   loadCliConfig: vi.fn(),
 }));
 
+vi.mock('../config/settings.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('../config/settings.js')>();
+  return {
+    ...actual,
+    loadSettings: vi.fn(),
+  };
+});
+
 vi.mock('node:crypto', () => ({
   randomUUID: () => 'test-session-id',
 }));
@@ -95,6 +107,10 @@ describe('GeminiAgent', () => {
       initialize: vi.fn(),
       getFileSystemService: vi.fn(),
       setFileSystemService: vi.fn(),
+      getContentGeneratorConfig: vi.fn(),
+      getActiveModel: vi.fn().mockReturnValue('gemini-pro'),
+      getModel: vi.fn().mockReturnValue('gemini-pro'),
+      getPreviewFeatures: vi.fn().mockReturnValue({}),
       getGeminiClient: vi.fn().mockReturnValue({
         startChat: vi.fn().mockResolvedValue({}),
       }),
@@ -117,6 +133,13 @@ describe('GeminiAgent', () => {
     } as unknown as Mocked<acp.AgentSideConnection>;
 
     (loadCliConfig as unknown as Mock).mockResolvedValue(mockConfig);
+    (loadSettings as unknown as Mock).mockImplementation(() => ({
+      merged: {
+        security: { auth: { selectedType: AuthType.LOGIN_WITH_GOOGLE } },
+        mcpServers: {},
+      },
+      setValue: vi.fn(),
+    }));
 
     agent = new GeminiAgent(mockConfig, mockSettings, mockArgv, mockConnection);
   });
@@ -148,6 +171,9 @@ describe('GeminiAgent', () => {
   });
 
   it('should create a new session', async () => {
+    mockConfig.getContentGeneratorConfig = vi.fn().mockReturnValue({
+      apiKey: 'test-key',
+    });
     const response = await agent.newSession({
       cwd: '/tmp',
       mcpServers: [],
@@ -159,6 +185,28 @@ describe('GeminiAgent', () => {
     expect(mockConfig.getGeminiClient).toHaveBeenCalled();
   });
 
+  it('should fail session creation if Gemini API key is missing', async () => {
+    (loadSettings as unknown as Mock).mockImplementation(() => ({
+      merged: {
+        security: { auth: { selectedType: AuthType.USE_GEMINI } },
+        mcpServers: {},
+      },
+      setValue: vi.fn(),
+    }));
+    mockConfig.getContentGeneratorConfig = vi.fn().mockReturnValue({
+      apiKey: undefined,
+    });
+
+    await expect(
+      agent.newSession({
+        cwd: '/tmp',
+        mcpServers: [],
+      }),
+    ).rejects.toMatchObject({
+      message: 'Gemini API key is missing or not configured.',
+    });
+  });
+
   it('should create a new session with mcp servers', async () => {
     const mcpServers = [
       {
@@ -194,14 +242,14 @@ describe('GeminiAgent', () => {
     mockConfig.refreshAuth.mockRejectedValue(new Error('Auth failed'));
     const debugSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
 
-    // Should throw RequestError.authRequired()
+    // Should throw RequestError with custom message
     await expect(
       agent.newSession({
         cwd: '/tmp',
         mcpServers: [],
       }),
     ).rejects.toMatchObject({
-      message: 'Authentication required',
+      message: 'Auth failed',
     });
 
     debugSpy.mockRestore();