2 files changed, 59 insertions, 14 deletions

diff --git a/packages/cli/src/config/settings.test.ts b/packages/cli/src/config/settings.test.ts
index b99e8b79..ae655fe1 100644
--- a/packages/cli/src/config/settings.test.ts
+++ b/packages/cli/src/config/settings.test.ts
@@ -46,7 +46,7 @@ import stripJsonComments from 'strip-json-comments'; // Will be mocked separatel
 import {
   loadSettings,
   USER_SETTINGS_PATH, // This IS the mocked path.
-  SYSTEM_SETTINGS_PATH,
+  getSystemSettingsPath,
   SETTINGS_DIRECTORY_NAME, // This is from the original module, but used by the mock.
   SettingScope,
 } from './settings.js';
@@ -104,7 +104,7 @@ describe('Settings Loading and Merging', () => {
 
     it('should load system settings if only system file exists', () => {
       (mockFsExistsSync as Mock).mockImplementation(
-        (p: fs.PathLike) => p === SYSTEM_SETTINGS_PATH,
+        (p: fs.PathLike) => p === getSystemSettingsPath(),
       );
       const systemSettingsContent = {
         theme: 'system-default',
@@ -112,7 +112,7 @@ describe('Settings Loading and Merging', () => {
       };
       (fs.readFileSync as Mock).mockImplementation(
         (p: fs.PathOrFileDescriptor) => {
-          if (p === SYSTEM_SETTINGS_PATH)
+          if (p === getSystemSettingsPath())
             return JSON.stringify(systemSettingsContent);
           return '{}';
         },
@@ -121,7 +121,7 @@ describe('Settings Loading and Merging', () => {
       const settings = loadSettings(MOCK_WORKSPACE_DIR);
 
       expect(fs.readFileSync).toHaveBeenCalledWith(
-        SYSTEM_SETTINGS_PATH,
+        getSystemSettingsPath(),
         'utf-8',
       );
       expect(settings.system.settings).toEqual(systemSettingsContent);
@@ -257,7 +257,7 @@ describe('Settings Loading and Merging', () => {
 
       (fs.readFileSync as Mock).mockImplementation(
         (p: fs.PathOrFileDescriptor) => {
-          if (p === SYSTEM_SETTINGS_PATH)
+          if (p === getSystemSettingsPath())
             return JSON.stringify(systemSettingsContent);
           if (p === USER_SETTINGS_PATH)
             return JSON.stringify(userSettingsContent);
@@ -743,7 +743,7 @@ describe('Settings Loading and Merging', () => {
 
       (fs.readFileSync as Mock).mockImplementation(
         (p: fs.PathOrFileDescriptor) => {
-          if (p === SYSTEM_SETTINGS_PATH) {
+          if (p === getSystemSettingsPath()) {
             process.env.SHARED_VAR = 'system_value_for_system_read'; // Set for system settings read
             return JSON.stringify(systemSettingsContent);
           }
@@ -913,6 +913,50 @@ describe('Settings Loading and Merging', () => {
       delete process.env.TEST_HOST;
       delete process.env.TEST_PORT;
     });
+
+    describe('when GEMINI_CLI_SYSTEM_SETTINGS_PATH is set', () => {
+      const MOCK_ENV_SYSTEM_SETTINGS_PATH = '/mock/env/system/settings.json';
+
+      beforeEach(() => {
+        process.env.GEMINI_CLI_SYSTEM_SETTINGS_PATH =
+          MOCK_ENV_SYSTEM_SETTINGS_PATH;
+      });
+
+      afterEach(() => {
+        delete process.env.GEMINI_CLI_SYSTEM_SETTINGS_PATH;
+      });
+
+      it('should load system settings from the path specified in the environment variable', () => {
+        (mockFsExistsSync as Mock).mockImplementation(
+          (p: fs.PathLike) => p === MOCK_ENV_SYSTEM_SETTINGS_PATH,
+        );
+        const systemSettingsContent = {
+          theme: 'env-var-theme',
+          sandbox: true,
+        };
+        (fs.readFileSync as Mock).mockImplementation(
+          (p: fs.PathOrFileDescriptor) => {
+            if (p === MOCK_ENV_SYSTEM_SETTINGS_PATH)
+              return JSON.stringify(systemSettingsContent);
+            return '{}';
+          },
+        );
+
+        const settings = loadSettings(MOCK_WORKSPACE_DIR);
+
+        expect(fs.readFileSync).toHaveBeenCalledWith(
+          MOCK_ENV_SYSTEM_SETTINGS_PATH,
+          'utf-8',
+        );
+        expect(settings.system.path).toBe(MOCK_ENV_SYSTEM_SETTINGS_PATH);
+        expect(settings.system.settings).toEqual(systemSettingsContent);
+        expect(settings.merged).toEqual({
+          ...systemSettingsContent,
+          customThemes: {},
+          mcpServers: {},
+        });
+      });
+    });
   });
 
   describe('LoadedSettings class', () => {
diff --git a/packages/cli/src/config/settings.ts b/packages/cli/src/config/settings.ts
index 3cbfe22d..bc2206a7 100644
--- a/packages/cli/src/config/settings.ts
+++ b/packages/cli/src/config/settings.ts
@@ -25,7 +25,10 @@ export const SETTINGS_DIRECTORY_NAME = '.gemini';
 export const USER_SETTINGS_DIR = path.join(homedir(), SETTINGS_DIRECTORY_NAME);
 export const USER_SETTINGS_PATH = path.join(USER_SETTINGS_DIR, 'settings.json');
 
-function getSystemSettingsPath(): string {
+export function getSystemSettingsPath(): string {
+  if (process.env.GEMINI_CLI_SYSTEM_SETTINGS_PATH) {
+    return process.env.GEMINI_CLI_SYSTEM_SETTINGS_PATH;
+  }
   if (platform() === 'darwin') {
     return '/Library/Application Support/GeminiCli/settings.json';
   } else if (platform() === 'win32') {
@@ -35,8 +38,6 @@ function getSystemSettingsPath(): string {
   }
 }
 
-export const SYSTEM_SETTINGS_PATH = getSystemSettingsPath();
-
 export enum SettingScope {
   User = 'User',
   Workspace = 'Workspace',
@@ -297,11 +298,11 @@ export function loadSettings(workspaceDir: string): LoadedSettings {
   let userSettings: Settings = {};
   let workspaceSettings: Settings = {};
   const settingsErrors: SettingsError[] = [];
-
+  const systemSettingsPath = getSystemSettingsPath();
   // Load system settings
   try {
-    if (fs.existsSync(SYSTEM_SETTINGS_PATH)) {
-      const systemContent = fs.readFileSync(SYSTEM_SETTINGS_PATH, 'utf-8');
+    if (fs.existsSync(systemSettingsPath)) {
+      const systemContent = fs.readFileSync(systemSettingsPath, 'utf-8');
       const parsedSystemSettings = JSON.parse(
         stripJsonComments(systemContent),
       ) as Settings;
@@ -310,7 +311,7 @@ export function loadSettings(workspaceDir: string): LoadedSettings {
   } catch (error: unknown) {
     settingsErrors.push({
       message: getErrorMessage(error),
-      path: SYSTEM_SETTINGS_PATH,
+      path: systemSettingsPath,
     });
   }
 
@@ -368,7 +369,7 @@ export function loadSettings(workspaceDir: string): LoadedSettings {
 
   return new LoadedSettings(
     {
-      path: SYSTEM_SETTINGS_PATH,
+      path: systemSettingsPath,
       settings: systemSettings,
     },
     {