Introduce GEMINI_CLI_HOME for strict test isolation (#15907)

packages/core/src/code_assist/oauth-credential-storage.ts

@@ -9,9 +9,8 @@ import { HybridTokenStorage } from '../mcp/token-storage/hybrid-token-storage.js
 import { OAUTH_FILE } from '../config/storage.js';
 import type { OAuthCredentials } from '../mcp/token-storage/types.js';
 import * as path from 'node:path';
-import * as os from 'node:os';
 import { promises as fs } from 'node:fs';
-import { GEMINI_DIR } from '../utils/paths.js';
+import { GEMINI_DIR, homedir } from '../utils/paths.js';
 import { coreEvents } from '../utils/events.js';
 
 const KEYCHAIN_SERVICE_NAME = 'gemini-cli-oauth';
@@ -91,7 +90,7 @@ export class OAuthCredentialStorage {
       await this.storage.deleteCredentials(MAIN_ACCOUNT_KEY);
 
       // Also try to remove the old file if it exists
-      const oldFilePath = path.join(os.homedir(), GEMINI_DIR, OAUTH_FILE);
+      const oldFilePath = path.join(homedir(), GEMINI_DIR, OAUTH_FILE);
       await fs.rm(oldFilePath, { force: true }).catch(() => {});
     } catch (error: unknown) {
       coreEvents.emitFeedback(
@@ -107,7 +106,7 @@ export class OAuthCredentialStorage {
    * Migrate credentials from old file-based storage to keychain
    */
   private static async migrateFromFileStorage(): Promise<Credentials | null> {
-    const oldFilePath = path.join(os.homedir(), GEMINI_DIR, OAUTH_FILE);
+    const oldFilePath = path.join(homedir(), GEMINI_DIR, OAUTH_FILE);
 
     let credsJson: string;
     try {

packages/core/src/code_assist/oauth2.test.ts

@@ -26,16 +26,24 @@ import { AuthType } from '../core/contentGenerator.js';
 import type { Config } from '../config/config.js';
 import readline from 'node:readline';
 import { FORCE_ENCRYPTED_FILE_ENV_VAR } from '../mcp/token-storage/index.js';
-import { GEMINI_DIR } from '../utils/paths.js';
+import { GEMINI_DIR, homedir as pathsHomedir } from '../utils/paths.js';
 import { debugLogger } from '../utils/debugLogger.js';
 import { writeToStdout } from '../utils/stdio.js';
 import { FatalCancellationError } from '../utils/errors.js';
 import process from 'node:process';
 
-vi.mock('os', async (importOriginal) => {
-  const os = await importOriginal<typeof import('os')>();
+vi.mock('node:os', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('node:os')>();
   return {
-    ...os,
+    ...actual,
+    homedir: vi.fn(),
+  };
+});
+
+vi.mock('../utils/paths.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('../utils/paths.js')>();
+  return {
+    ...actual,
     homedir: vi.fn(),
   };
 });
@@ -89,6 +97,7 @@ describe('oauth2', () => {
         path.join(os.tmpdir(), 'gemini-cli-test-home-'),
       );
       vi.mocked(os.homedir).mockReturnValue(tempHomeDir);
+      vi.mocked(pathsHomedir).mockReturnValue(tempHomeDir);
     });
     afterEach(() => {
       fs.rmSync(tempHomeDir, { recursive: true, force: true });
@@ -1129,15 +1138,10 @@ describe('oauth2', () => {
           () => mockHttpServer as unknown as http.Server,
         );
 
-        // Mock process.on to immediately trigger SIGINT
+        // Mock process.on to capture SIGINT handler
         const processOnSpy = vi
           .spyOn(process, 'on')
-          .mockImplementation((event, listener: () => void) => {
-            if (event === 'SIGINT') {
-              listener();
-            }
-            return process;
-          });
+          .mockImplementation(() => process);
 
         const processRemoveListenerSpy = vi.spyOn(process, 'removeListener');
 
@@ -1146,6 +1150,24 @@ describe('oauth2', () => {
           mockConfig,
         );
 
+        // Wait for the SIGINT handler to be registered
+        let sigIntHandler: (() => void) | undefined;
+        await vi.waitFor(() => {
+          const sigintCall = processOnSpy.mock.calls.find(
+            (call) => call[0] === 'SIGINT',
+          );
+          sigIntHandler = sigintCall?.[1] as (() => void) | undefined;
+          if (!sigIntHandler)
+            throw new Error('SIGINT handler not registered yet');
+        });
+
+        expect(sigIntHandler).toBeDefined();
+
+        // Trigger SIGINT
+        if (sigIntHandler) {
+          sigIntHandler();
+        }
+
         await expect(clientPromise).rejects.toThrow(FatalCancellationError);
         expect(processRemoveListenerSpy).toHaveBeenCalledWith(
           'SIGINT',
@@ -1180,17 +1202,10 @@ describe('oauth2', () => {
           () => mockHttpServer as unknown as http.Server,
         );
 
-        // Spy on process.stdin.on and immediately trigger Ctrl+C
+        // Spy on process.stdin.on to capture data handler
         const stdinOnSpy = vi
           .spyOn(process.stdin, 'on')
-          .mockImplementation(
-            (event: string, listener: (data: Buffer) => void) => {
-              if (event === 'data') {
-                listener(Buffer.from([0x03]));
-              }
-              return process.stdin;
-            },
-          );
+          .mockImplementation(() => process.stdin);
 
         const stdinRemoveListenerSpy = vi.spyOn(
           process.stdin,
@@ -1202,6 +1217,23 @@ describe('oauth2', () => {
           mockConfig,
         );
 
+        // Wait for the stdin handler to be registered
+        let dataHandler: ((data: Buffer) => void) | undefined;
+        await vi.waitFor(() => {
+          const dataCall = stdinOnSpy.mock.calls.find(
+            (call: [string, ...unknown[]]) => call[0] === 'data',
+          );
+          dataHandler = dataCall?.[1] as ((data: Buffer) => void) | undefined;
+          if (!dataHandler) throw new Error('stdin handler not registered yet');
+        });
+
+        expect(dataHandler).toBeDefined();
+
+        // Trigger Ctrl+C
+        if (dataHandler) {
+          dataHandler(Buffer.from([0x03]));
+        }
+
         await expect(clientPromise).rejects.toThrow(FatalCancellationError);
         expect(stdinRemoveListenerSpy).toHaveBeenCalledWith(
           'data',
@@ -1302,7 +1334,8 @@ describe('oauth2', () => {
       tempHomeDir = fs.mkdtempSync(
         path.join(os.tmpdir(), 'gemini-cli-test-home-'),
       );
-      (os.homedir as Mock).mockReturnValue(tempHomeDir);
+      vi.mocked(os.homedir).mockReturnValue(tempHomeDir);
+      vi.mocked(pathsHomedir).mockReturnValue(tempHomeDir);
     });
 
     afterEach(() => {

packages/core/src/code_assist/oauth2.ts

@@ -336,7 +336,7 @@ async function initOauthClient(
 
       // Note that SIGINT might not get raised on Ctrl+C in raw mode
       // so we also need to look for Ctrl+C directly in stdin.
-      stdinHandler = (data) => {
+      stdinHandler = (data: Buffer) => {
         if (data.includes(0x03)) {
           reject(
             new FatalCancellationError('Authentication cancelled by user.'),

packages/core/src/config/storage.ts

@@ -8,7 +8,7 @@ import * as path from 'node:path';
 import * as os from 'node:os';
 import * as crypto from 'node:crypto';
 import * as fs from 'node:fs';
-import { GEMINI_DIR } from '../utils/paths.js';
+import { GEMINI_DIR, homedir } from '../utils/paths.js';
 
 export const GOOGLE_ACCOUNTS_FILENAME = 'google_accounts.json';
 export const OAUTH_FILE = 'oauth_creds.json';
@@ -23,7 +23,7 @@ export class Storage {
   }
 
   static getGlobalGeminiDir(): string {
-    const homeDir = os.homedir();
+    const homeDir = homedir();
     if (!homeDir) {
       return path.join(os.tmpdir(), GEMINI_DIR);
     }

packages/core/src/core/prompts.ts

@@ -6,7 +6,6 @@
 
 import path from 'node:path';
 import fs from 'node:fs';
-import os from 'node:os';
 import {
   EDIT_TOOL_NAME,
   GLOB_TOOL_NAME,
@@ -23,7 +22,7 @@ import process from 'node:process';
 import { isGitRepository } from '../utils/gitUtils.js';
 import { CodebaseInvestigatorAgent } from '../agents/codebase-investigator.js';
 import type { Config } from '../config/config.js';
-import { GEMINI_DIR } from '../utils/paths.js';
+import { GEMINI_DIR, homedir } from '../utils/paths.js';
 import { debugLogger } from '../utils/debugLogger.js';
 import { WriteTodosTool } from '../tools/write-todos.js';
 import { resolveModel, isPreviewModel } from '../config/models.js';
@@ -53,7 +52,7 @@ export function resolvePathFromEnv(envVar?: string): {
   // Safely expand the tilde (~) character to the user's home directory.
   if (customPath.startsWith('~/') || customPath === '~') {
     try {
-      const home = os.homedir(); // This is the call that can throw an error.
+      const home = homedir(); // This is the call that can throw an error.
       if (customPath === '~') {
         customPath = home;
       } else {

packages/core/src/ide/ide-installer.test.ts

@@ -14,8 +14,15 @@ vi.mock('node:child_process', async (importOriginal) => {
     spawnSync: vi.fn(() => ({ status: 0 })),
   };
 });
-vi.mock('fs');
-vi.mock('os');
+vi.mock('node:fs');
+vi.mock('node:os');
+vi.mock('../utils/paths.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('../utils/paths.js')>();
+  return {
+    ...actual,
+    homedir: vi.fn(),
+  };
+});
 
 import { describe, it, expect, beforeEach, afterEach } from 'vitest';
 import { getIdeInstaller } from './ide-installer.js';
@@ -24,12 +31,14 @@ import * as fs from 'node:fs';
 import * as os from 'node:os';
 import * as path from 'node:path';
 import { IDE_DEFINITIONS, type IdeInfo } from './detect-ide.js';
+import { homedir as pathsHomedir } from '../utils/paths.js';
 
 describe('ide-installer', () => {
   const HOME_DIR = '/home/user';
 
   beforeEach(() => {
     vi.spyOn(os, 'homedir').mockReturnValue(HOME_DIR);
+    vi.mocked(pathsHomedir).mockReturnValue(HOME_DIR);
   });
 
   afterEach(() => {

packages/core/src/ide/ide-installer.ts

@@ -8,9 +8,9 @@ import * as child_process from 'node:child_process';
 import * as process from 'node:process';
 import * as path from 'node:path';
 import * as fs from 'node:fs';
-import * as os from 'node:os';
 import { IDE_DEFINITIONS, type IdeInfo } from './detect-ide.js';
 import { GEMINI_CLI_COMPANION_EXTENSION_NAME } from './constants.js';
+import { homedir } from '../utils/paths.js';
 
 export interface IdeInstaller {
   install(): Promise<InstallResult>;
@@ -49,7 +49,7 @@ async function findCommand(
 
   // 2. Check common installation locations.
   const locations: string[] = [];
-  const homeDir = os.homedir();
+  const homeDir = homedir();
 
   if (command === 'code' || command === 'code.cmd') {
     if (platform === 'darwin') {

packages/core/src/index.ts

@@ -50,6 +50,7 @@ export * from './code_assist/telemetry.js';
 export * from './core/apiKeyCredentialStorage.js';
 
 // Export utilities
+export { homedir, tmpdir } from './utils/paths.js';
 export * from './utils/paths.js';
 export * from './utils/schemaValidator.js';
 export * from './utils/errors.js';

packages/core/src/mcp/token-storage/file-token-storage.ts

@@ -10,7 +10,7 @@ import * as os from 'node:os';
 import * as crypto from 'node:crypto';
 import { BaseTokenStorage } from './base-token-storage.js';
 import type { OAuthCredentials } from './types.js';
-import { GEMINI_DIR } from '../../utils/paths.js';
+import { GEMINI_DIR, homedir } from '../../utils/paths.js';
 
 export class FileTokenStorage extends BaseTokenStorage {
   private readonly tokenFilePath: string;
@@ -18,7 +18,7 @@ export class FileTokenStorage extends BaseTokenStorage {
 
   constructor(serviceName: string) {
     super(serviceName);
-    const configDir = path.join(os.homedir(), GEMINI_DIR);
+    const configDir = path.join(homedir(), GEMINI_DIR);
     this.tokenFilePath = path.join(configDir, 'mcp-oauth-tokens-v2.json');
     this.encryptionKey = this.deriveEncryptionKey();
   }

packages/core/src/services/gitService.test.ts

@@ -18,7 +18,11 @@ import { Storage } from '../config/storage.js';
 import * as path from 'node:path';
 import * as fs from 'node:fs/promises';
 import * as os from 'node:os';
-import { getProjectHash, GEMINI_DIR } from '../utils/paths.js';
+import {
+  getProjectHash,
+  GEMINI_DIR,
+  homedir as pathsHomedir,
+} from '../utils/paths.js';
 import { spawnAsync } from '../utils/shell-utils.js';
 
 vi.mock('../utils/shell-utils.js', () => ({
@@ -52,7 +56,7 @@ vi.mock('../utils/gitUtils.js', () => ({
 }));
 
 const hoistedMockHomedir = vi.hoisted(() => vi.fn());
-vi.mock('os', async (importOriginal) => {
+vi.mock('node:os', async (importOriginal) => {
   const actual = await importOriginal<typeof os>();
   return {
     ...actual,
@@ -60,6 +64,14 @@ vi.mock('os', async (importOriginal) => {
   };
 });
 
+vi.mock('../utils/paths.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('../utils/paths.js')>();
+  return {
+    ...actual,
+    homedir: vi.fn(),
+  };
+});
+
 const hoistedMockDebugLogger = vi.hoisted(() => ({
   debug: vi.fn(),
   warn: vi.fn(),
@@ -93,6 +105,7 @@ describe('GitService', () => {
     });
 
     hoistedMockHomedir.mockReturnValue(homedir);
+    (pathsHomedir as Mock).mockReturnValue(homedir);
 
     hoistedMockEnv.mockImplementation(() => ({
       checkIsRepo: hoistedMockCheckIsRepo,

packages/core/src/utils/installationManager.test.ts

@@ -11,7 +11,7 @@ import * as fs from 'node:fs';
 import * as os from 'node:os';
 import path from 'node:path';
 import { randomUUID } from 'node:crypto';
-import { GEMINI_DIR } from './paths.js';
+import { GEMINI_DIR, homedir as pathsHomedir } from './paths.js';
 import { debugLogger } from './debugLogger.js';
 
 vi.mock('node:fs', async (importOriginal) => {
@@ -23,22 +23,30 @@ vi.mock('node:fs', async (importOriginal) => {
   } as typeof actual;
 });
 
-vi.mock('os', async (importOriginal) => {
-  const os = await importOriginal<typeof import('os')>();
+vi.mock('node:os', async (importOriginal) => {
+  const os = await importOriginal<typeof import('node:os')>();
   return {
     ...os,
     homedir: vi.fn(),
   };
 });
 
-vi.mock('crypto', async (importOriginal) => {
-  const crypto = await importOriginal<typeof import('crypto')>();
+vi.mock('node:crypto', async (importOriginal) => {
+  const crypto = await importOriginal<typeof import('node:crypto')>();
   return {
     ...crypto,
     randomUUID: vi.fn(),
   };
 });
 
+vi.mock('./paths.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('./paths.js')>();
+  return {
+    ...actual,
+    homedir: vi.fn(),
+  };
+});
+
 describe('InstallationManager', () => {
   let tempHomeDir: string;
   let installationManager: InstallationManager;
@@ -49,6 +57,7 @@ describe('InstallationManager', () => {
     tempHomeDir = fs.mkdtempSync(
       path.join(os.tmpdir(), 'gemini-cli-test-home-'),
     );
+    (pathsHomedir as Mock).mockReturnValue(tempHomeDir);
     (os.homedir as Mock).mockReturnValue(tempHomeDir);
     installationManager = new InstallationManager();
   });

packages/core/src/utils/memoryDiscovery.test.ts

@@ -35,6 +35,16 @@ vi.mock('os', async (importOriginal) => {
   };
 });
 
+vi.mock('../utils/paths.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('../utils/paths.js')>();
+  return {
+    ...actual,
+    homedir: vi.fn(),
+  };
+});
+
+import { homedir as pathsHomedir } from './paths.js';
+
 describe('memoryDiscovery', () => {
   const DEFAULT_FOLDER_TRUST = true;
   let testRootDir: string;
@@ -67,6 +77,7 @@ describe('memoryDiscovery', () => {
     cwd = await createEmptyDir(path.join(projectRoot, 'src'));
     homedir = await createEmptyDir(path.join(testRootDir, 'userhome'));
     vi.mocked(os.homedir).mockReturnValue(homedir);
+    vi.mocked(pathsHomedir).mockReturnValue(homedir);
   });
 
   afterEach(async () => {

packages/core/src/utils/memoryDiscovery.ts

@@ -7,14 +7,13 @@
 import * as fs from 'node:fs/promises';
 import * as fsSync from 'node:fs';
 import * as path from 'node:path';
-import { homedir } from 'node:os';
 import { bfsFileSearch } from './bfsFileSearch.js';
 import { getAllGeminiMdFilenames } from '../tools/memoryTool.js';
 import type { FileDiscoveryService } from '../services/fileDiscoveryService.js';
 import { processImports } from './memoryImportProcessor.js';
 import type { FileFilteringOptions } from '../config/constants.js';
 import { DEFAULT_MEMORY_FILE_FILTERING_OPTIONS } from '../config/constants.js';
-import { GEMINI_DIR } from './paths.js';
+import { GEMINI_DIR, homedir } from './paths.js';
 import type { ExtensionLoader } from './extensionLoader.js';
 import { debugLogger } from './debugLogger.js';
 import type { Config } from '../config/config.js';

packages/core/src/utils/paths.ts

@@ -6,6 +6,7 @@
 
 import path from 'node:path';
 import os from 'node:os';
+import process from 'node:process';
 import * as crypto from 'node:crypto';
 
 export const GEMINI_DIR = '.gemini';
@@ -18,13 +19,33 @@ export const GOOGLE_ACCOUNTS_FILENAME = 'google_accounts.json';
  */
 export const SHELL_SPECIAL_CHARS = /[ \t()[\]{};|*?$`'"#&<>!~]/;
 
+/**
+ * Returns the home directory.
+ * If GEMINI_CLI_HOME environment variable is set, it returns its value.
+ * Otherwise, it returns the user's home directory.
+ */
+export function homedir(): string {
+  const envHome = process.env['GEMINI_CLI_HOME'];
+  if (envHome) {
+    return envHome;
+  }
+  return os.homedir();
+}
+
+/**
+ * Returns the operating system's default directory for temporary files.
+ */
+export function tmpdir(): string {
+  return os.tmpdir();
+}
+
 /**
  * Replaces the home directory with a tilde.
  * @param path - The path to tildeify.
  * @returns The tildeified path.
  */
 export function tildeifyPath(path: string): string {
-  const homeDir = os.homedir();
+  const homeDir = homedir();
   if (path.startsWith(homeDir)) {
     return path.replace(homeDir, '~');
   }

packages/core/src/utils/userAccountManager.test.ts

@@ -10,13 +10,13 @@ import { UserAccountManager } from './userAccountManager.js';
 import * as fs from 'node:fs';
 import * as os from 'node:os';
 import path from 'node:path';
-import { GEMINI_DIR } from './paths.js';
+import { GEMINI_DIR, homedir as pathsHomedir } from './paths.js';
 import { debugLogger } from './debugLogger.js';
 
-vi.mock('os', async (importOriginal) => {
-  const os = await importOriginal<typeof import('os')>();
+vi.mock('./paths.js', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('./paths.js')>();
   return {
-    ...os,
+    ...actual,
     homedir: vi.fn(),
   };
 });
@@ -30,7 +30,7 @@ describe('UserAccountManager', () => {
     tempHomeDir = fs.mkdtempSync(
       path.join(os.tmpdir(), 'gemini-cli-test-home-'),
     );
-    (os.homedir as Mock).mockReturnValue(tempHomeDir);
+    (pathsHomedir as Mock).mockReturnValue(tempHomeDir);
     accountsFile = () =>
       path.join(tempHomeDir, GEMINI_DIR, 'google_accounts.json');
     userAccountManager = new UserAccountManager();