refactor: migrate checks.ts utility to core and deduplicate (#18139)

packages/cli/src/ui/commands/rewindCommand.tsx

@@ -14,14 +14,14 @@ import { type HistoryItem } from '../types.js';
 import { convertSessionToHistoryFormats } from '../hooks/useSessionBrowser.js';
 import { revertFileChanges } from '../utils/rewindFileOps.js';
 import { RewindOutcome } from '../components/RewindConfirmation.js';
-import { checkExhaustive } from '../../utils/checks.js';
-
 import type { Content } from '@google/genai';
-import type {
-  ChatRecordingService,
-  GeminiClient,
+import {
+  checkExhaustive,
+  coreEvents,
+  debugLogger,
+  type ChatRecordingService,
+  type GeminiClient,
 } from '@google/gemini-cli-core';
-import { coreEvents, debugLogger } from '@google/gemini-cli-core';
 
 /**
  * Helper function to handle the core logic of rewinding a conversation.

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

@@ -21,7 +21,7 @@ import type { SelectionListItem } from '../hooks/useSelectionList.js';
 import { TabHeader, type Tab } from './shared/TabHeader.js';
 import { useKeypress, type Key } from '../hooks/useKeypress.js';
 import { keyMatchers, Command } from '../keyMatchers.js';
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 import { TextInput } from './shared/TextInput.js';
 import { useTextBuffer } from './shared/text-buffer.js';
 import { getCachedStringWidth } from '../utils/textUtils.js';

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

@@ -7,7 +7,7 @@
 import type React from 'react';
 import { Box, Text } from 'ink';
 import { theme } from '../semantic-colors.js';
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 
 export type ChecklistStatus =
   | 'pending'

packages/cli/src/ui/components/shared/vim-buffer-actions.ts

@@ -19,7 +19,7 @@ import {
   findWordEndInLine,
 } from './text-buffer.js';
 import { cpLen, toCodePoints } from '../../utils/textUtils.js';
-import { assumeExhaustive } from '../../../utils/checks.js';
+import { assumeExhaustive } from '@google/gemini-cli-core';
 
 // Check if we're at the end of a base word (on the last base character)
 // Returns true if current position has a base character followed only by combining marks until non-word

packages/cli/src/ui/hooks/toolMapping.ts

@@ -18,7 +18,7 @@ import {
   type IndividualToolCallDisplay,
 } from '../types.js';
 
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 
 export function mapCoreStatusToDisplayStatus(
   coreStatus: CoreStatus,

packages/cli/src/ui/hooks/useExtensionUpdates.ts

@@ -19,7 +19,7 @@ import {
   updateExtension,
 } from '../../config/extensions/update.js';
 import { type ExtensionUpdateInfo } from '../../config/extension.js';
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 import type { ExtensionManager } from '../../config/extension-manager.js';
 
 type ConfirmationRequestWrapper = {

packages/cli/src/ui/state/extensions.ts

@@ -5,7 +5,7 @@
  */
 
 import type { ExtensionUpdateInfo } from '../../config/extension.js';
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 
 export enum ExtensionUpdateState {
   CHECKING_FOR_UPDATES = 'checking for updates',

packages/cli/src/utils/checks.test.ts

@@ -1,32 +0,0 @@
-/**
- * @license
- * Copyright 2025 Google LLC
- * SPDX-License-Identifier: Apache-2.0
- */
-
-import { describe, it, expect } from 'vitest';
-import { checkExhaustive, assumeExhaustive } from './checks.js';
-
-describe('checks', () => {
-  describe('checkExhaustive', () => {
-    it('should throw an error with default message', () => {
-      expect(() => {
-        checkExhaustive('unexpected' as never);
-      }).toThrow('unexpected value unexpected!');
-    });
-
-    it('should throw an error with custom message', () => {
-      expect(() => {
-        checkExhaustive('unexpected' as never, 'custom message');
-      }).toThrow('custom message');
-    });
-  });
-
-  describe('assumeExhaustive', () => {
-    it('should do nothing', () => {
-      expect(() => {
-        assumeExhaustive('unexpected' as never);
-      }).not.toThrow();
-    });
-  });
-});

packages/cli/src/utils/checks.ts

@@ -1,28 +0,0 @@
-/**
- * @license
- * Copyright 2025 Google LLC
- * SPDX-License-Identifier: Apache-2.0
- */
-
-/* Fail to compile on unexpected values. */
-export function assumeExhaustive(_value: never): void {}
-
-/**
- * Throws an exception on unexpected values.
- *
- * A common use case is switch statements:
- * switch(enumValue) {
- *   case Enum.A:
- *   case Enum.B:
- *     break;
- *   default:
- *     checkExhaustive(enumValue);
- * }
- */
-export function checkExhaustive(
-  value: never,
-  msg = `unexpected value ${value}!`,
-): never {
-  assumeExhaustive(value);
-  throw new Error(msg);
-}

packages/cli/src/utils/sessionUtils.ts

@@ -4,20 +4,18 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import type {
-  Config,
-  ConversationRecord,
-  MessageRecord,
-} from '@google/gemini-cli-core';
 import {
+  checkExhaustive,
   partListUnionToString,
   SESSION_FILE_PREFIX,
+  type Config,
+  type ConversationRecord,
+  type MessageRecord,
 } from '@google/gemini-cli-core';
 import * as fs from 'node:fs/promises';
 import path from 'node:path';
 import { stripUnsafeCharacters } from '../ui/utils/textUtils.js';
 import type { Part } from '@google/genai';
-import { checkExhaustive } from './checks.js';
 import {
   MessageType,
   ToolCallStatus,