fix(cli): prevent spam loop when preferredEditor is invalid (#25324)

Co-authored-by: Tommaso Sciortino <sciortino@gmail.com>

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

@@ -175,4 +175,45 @@ describe('EditorSettingsDialog', () => {
     }
     expect(frame).toContain('(Also modified');
   });
+
+  it('emits error feedback only once when preferredEditor is invalid', async () => {
+    const mockEmitFeedback = vi.fn();
+    vi.spyOn(
+      await import('@google/gemini-cli-core').then((m) => m.coreEvents),
+      'emitFeedback',
+    ).mockImplementation(mockEmitFeedback);
+
+    const invalidSettings = {
+      forScope: (_scope: string) => ({
+        settings: {
+          general: {
+            preferredEditor: 'invalideditor',
+          },
+        },
+      }),
+      merged: {
+        general: {
+          preferredEditor: 'invalideditor',
+        },
+      },
+    } as unknown as LoadedSettings;
+
+    const { unmount } = await renderWithProvider(
+      <EditorSettingsDialog
+        onSelect={vi.fn()}
+        settings={invalidSettings}
+        onExit={vi.fn()}
+      />,
+    );
+
+    await waitFor(() => {
+      expect(mockEmitFeedback).toHaveBeenCalledWith(
+        'error',
+        'Editor is not supported: invalideditor',
+      );
+    });
+
+    expect(mockEmitFeedback).toHaveBeenCalledTimes(1);
+    unmount();
+  });
 });

packages/cli/src/ui/components/EditorSettingsDialog.tsx

@@ -5,7 +5,7 @@
  */
 
 import type React from 'react';
-import { useState } from 'react';
+import { useState, useEffect } from 'react';
 import { Box, Text } from 'ink';
 import { theme } from '../semantic-colors.js';
 import {
@@ -22,6 +22,7 @@ import {
   type EditorType,
   isEditorAvailable,
   EDITOR_DISPLAY_NAMES,
+  coreEvents,
 } from '@google/gemini-cli-core';
 import { useKeypress } from '../hooks/useKeypress.js';
 
@@ -70,10 +71,20 @@ export function EditorSettingsDialog({
         (item: EditorDisplay) => item.type === currentPreference,
       )
     : 0;
-  if (editorIndex === -1) {
+  const isUnsupportedEditor = editorIndex === -1;
+  if (isUnsupportedEditor) {
     editorIndex = 0;
   }
 
+  useEffect(() => {
+    if (isUnsupportedEditor && currentPreference) {
+      coreEvents.emitFeedback(
+        'error',
+        `Editor is not supported: ${currentPreference}`,
+      );
+    }
+  }, [isUnsupportedEditor, currentPreference]);
+
   const scopeItems: Array<{
     label: string;
     value: LoadableSettingScope;

packages/cli/src/ui/components/__snapshots__/InputPrompt.test.tsx.snap

@@ -60,12 +60,6 @@ exports[`InputPrompt > Highlighting and Cursor Display > single-line scenarios >
 ────────────────────────────────────────────────────────────────────────────────────────────────────"
 `;
 
-exports[`InputPrompt > Highlighting and Cursor Display > single-line scenarios > should display cursor correctly 'at the end of the line' 2`] = `
-"────────────────────────────────────────────────────────────────────────────────────────────────────
- > hello
-────────────────────────────────────────────────────────────────────────────────────────────────────"
-`;
-
 exports[`InputPrompt > Highlighting and Cursor Display > single-line scenarios > should display cursor correctly 'for multi-byte unicode characters' 1`] = `
 "────────────────────────────────────────────────────────────────────────────────────────────────────
  > hello 👍 world