fix(cli): hide read-only settings scopes

packages/cli/src/config/settings.test.ts

@@ -3003,6 +3003,44 @@ describe('Settings Loading and Merging', () => {
       expect(snap1).toBe(snap2);
     });
 
+    it('getSnapshot() should preserve readOnly metadata for each scope', () => {
+      const readonlySettings = new LoadedSettings(
+        {
+          path: getSystemSettingsPath(),
+          settings: {},
+          originalSettings: {},
+          readOnly: true,
+        },
+        {
+          path: getSystemDefaultsPath(),
+          settings: {},
+          originalSettings: {},
+          readOnly: true,
+        },
+        {
+          path: USER_SETTINGS_PATH,
+          settings: {},
+          originalSettings: {},
+          readOnly: false,
+        },
+        {
+          path: MOCK_WORKSPACE_SETTINGS_PATH,
+          settings: {},
+          originalSettings: {},
+          readOnly: true,
+        },
+        true,
+        [],
+      );
+
+      const snapshot = readonlySettings.getSnapshot();
+
+      expect(snapshot.system.readOnly).toBe(true);
+      expect(snapshot.systemDefaults.readOnly).toBe(true);
+      expect(snapshot.user.readOnly).toBe(false);
+      expect(snapshot.workspace.readOnly).toBe(true);
+    });
+
     it('setValue() should create a new snapshot reference and emit event', () => {
       const oldSnapshot = loadedSettings.getSnapshot();
       const oldUserRef = oldSnapshot.user.settings;

packages/cli/src/config/settings.ts

@@ -397,8 +397,7 @@ export class LoadedSettings {
 
   private computeSnapshot(): LoadedSettingsSnapshot {
     const cloneSettingsFile = (file: SettingsFile): SettingsFile => ({
-      path: file.path,
-      rawJson: file.rawJson,
+      ...file,
       settings: structuredClone(file.settings),
       originalSettings: structuredClone(file.originalSettings),
     });

packages/cli/src/test-utils/settings.ts

@@ -16,6 +16,7 @@ export interface MockSettingsFile {
   settings: any;
   originalSettings: any;
   path: string;
+  readOnly?: boolean;
 }
 
 interface CreateMockSettingsOptions {

packages/cli/src/ui/components/SettingsDialog.test.tsx

@@ -25,7 +25,10 @@ import { waitFor } from '../../test-utils/async.js';
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
 import { SettingsDialog } from './SettingsDialog.js';
 import { SettingScope } from '../../config/settings.js';
-import { createMockSettings } from '../../test-utils/settings.js';
+import {
+  createMockSettings,
+  type MockSettingsFile,
+} from '../../test-utils/settings.js';
 import { makeFakeConfig } from '@google/gemini-cli-core';
 import { act } from 'react';
 import { TEST_ONLY } from '../../utils/settingsUtils.js';
@@ -250,6 +253,17 @@ const renderDialog = async (
     },
   );
 
+const createSettingsFile = (
+  path: string,
+  settings: Record<string, unknown> = {},
+  readOnly?: boolean,
+): MockSettingsFile => ({
+  settings,
+  originalSettings: settings,
+  path,
+  readOnly,
+});
+
 describe('SettingsDialog', () => {
   beforeEach(() => {
     vi.clearAllMocks();
@@ -588,6 +602,131 @@ describe('SettingsDialog', () => {
 
       unmount();
     });
+
+    it('should not offer read-only system settings as an editable target', async () => {
+      const settings = createMockSettings({
+        system: createSettingsFile('', {}, true),
+      });
+      const onSelect = vi.fn();
+
+      const { lastFrame, unmount } = await renderDialog(settings, onSelect);
+
+      await waitFor(() => {
+        expect(lastFrame()).toContain('Apply To');
+      });
+
+      const output = lastFrame();
+      expect(output).toContain('User Settings');
+      expect(output).toContain('Workspace Settings');
+      expect(output).not.toContain('System Settings');
+
+      unmount();
+    });
+
+    it('should not offer a read-only home-directory workspace as an editable target', async () => {
+      const settings = createMockSettings({
+        user: createSettingsFile('/mock/home/.gemini/settings.json'),
+        system: createSettingsFile('/mock/system/settings.json', {}, true),
+        systemDefaults: createSettingsFile(
+          '/mock/system-defaults/settings.json',
+          {},
+          true,
+        ),
+        workspace: createSettingsFile('', {}, true),
+      });
+      const setValueSpy = vi.spyOn(settings, 'setValue');
+      const onSelect = vi.fn();
+
+      const { lastFrame, stdin, unmount, waitUntilReady } = await renderDialog(
+        settings,
+        onSelect,
+      );
+
+      await waitFor(() => {
+        expect(lastFrame()).toContain('Vim Mode');
+      });
+
+      const output = lastFrame();
+      expect(output).not.toContain('Workspace Settings');
+      expect(output).not.toContain('System Settings');
+
+      await act(async () => {
+        stdin.write(TerminalKeys.ENTER as string);
+      });
+      await waitUntilReady();
+
+      expect(setValueSpy).toHaveBeenCalledWith(
+        SettingScope.User,
+        'general.vimMode',
+        true,
+      );
+
+      unmount();
+    });
+
+    it('should fall back to the first writable scope when the selected scope is read-only', async () => {
+      const settings = createMockSettings({
+        user: createSettingsFile('', {}, true),
+        system: createSettingsFile('', {}, true),
+        workspace: createSettingsFile('/mock/workspace/.gemini/settings.json'),
+      });
+      const setValueSpy = vi.spyOn(settings, 'setValue');
+      const onSelect = vi.fn();
+
+      const { lastFrame, stdin, unmount, waitUntilReady } = await renderDialog(
+        settings,
+        onSelect,
+      );
+
+      await waitFor(() => {
+        expect(lastFrame()).toContain('Vim Mode');
+      });
+
+      await act(async () => {
+        stdin.write(TerminalKeys.ENTER as string);
+      });
+      await waitUntilReady();
+
+      expect(setValueSpy).toHaveBeenCalledWith(
+        SettingScope.Workspace,
+        'general.vimMode',
+        true,
+      );
+
+      unmount();
+    });
+
+    it('should not save when all editable scopes are read-only', async () => {
+      const settings = createMockSettings({
+        user: createSettingsFile('', {}, true),
+        system: createSettingsFile('', {}, true),
+        workspace: createSettingsFile(
+          '/mock/workspace/.gemini/settings.json',
+          {},
+          true,
+        ),
+      });
+      const setValueSpy = vi.spyOn(settings, 'setValue');
+      const onSelect = vi.fn();
+
+      const { lastFrame, stdin, unmount, waitUntilReady } = await renderDialog(
+        settings,
+        onSelect,
+      );
+
+      await waitFor(() => {
+        expect(lastFrame()).toContain('Vim Mode');
+      });
+
+      await act(async () => {
+        stdin.write(TerminalKeys.ENTER as string);
+      });
+      await waitUntilReady();
+
+      expect(setValueSpy).not.toHaveBeenCalled();
+
+      unmount();
+    });
   });
 
   describe('Restart Prompt', () => {