1 files changed, 277 insertions, 0 deletions
diff --git a/packages/cli/src/ui/commands/chatCommand.test.ts b/packages/cli/src/ui/commands/chatCommand.test.ts
new file mode 100644
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+++ b/packages/cli/src/ui/commands/chatCommand.test.ts
@@ -0,0 +1,277 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import {
+  vi,
+  describe,
+  it,
+  expect,
+  beforeEach,
+  afterEach,
+  Mocked,
+} from 'vitest';
+
+import {
+  type CommandContext,
+  MessageActionReturn,
+  SlashCommand,
+} from './types.js';
+import { createMockCommandContext } from '../../test-utils/mockCommandContext.js';
+import { Content } from '@google/genai';
+import { GeminiClient } from '@google/gemini-cli-core';
+
+import * as fsPromises from 'fs/promises';
+import { chatCommand } from './chatCommand.js';
+import { Stats } from 'fs';
+import { HistoryItemWithoutId } from '../types.js';
+
+vi.mock('fs/promises', () => ({
+  stat: vi.fn(),
+  readdir: vi.fn().mockResolvedValue(['file1.txt', 'file2.txt'] as string[]),
+}));
+
+describe('chatCommand', () => {
+  const mockFs = fsPromises as Mocked<typeof fsPromises>;
+
+  let mockContext: CommandContext;
+  let mockGetChat: ReturnType<typeof vi.fn>;
+  let mockSaveCheckpoint: ReturnType<typeof vi.fn>;
+  let mockLoadCheckpoint: ReturnType<typeof vi.fn>;
+  let mockGetHistory: ReturnType<typeof vi.fn>;
+
+  const getSubCommand = (name: 'list' | 'save' | 'resume'): SlashCommand => {
+    const subCommand = chatCommand.subCommands?.find(
+      (cmd) => cmd.name === name,
+    );
+    if (!subCommand) {
+      throw new Error(`/memory ${name} command not found.`);
+    }
+    return subCommand;
+  };
+
+  beforeEach(() => {
+    mockGetHistory = vi.fn().mockReturnValue([]);
+    mockGetChat = vi.fn().mockResolvedValue({
+      getHistory: mockGetHistory,
+    });
+    mockSaveCheckpoint = vi.fn().mockResolvedValue(undefined);
+    mockLoadCheckpoint = vi.fn().mockResolvedValue([]);
+
+    mockContext = createMockCommandContext({
+      services: {
+        config: {
+          getProjectTempDir: () => '/tmp/gemini',
+          getGeminiClient: () =>
+            ({
+              getChat: mockGetChat,
+            }) as unknown as GeminiClient,
+        },
+        logger: {
+          saveCheckpoint: mockSaveCheckpoint,
+          loadCheckpoint: mockLoadCheckpoint,
+          initialize: vi.fn().mockResolvedValue(undefined),
+        },
+      },
+    });
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('should have the correct main command definition', () => {
+    expect(chatCommand.name).toBe('chat');
+    expect(chatCommand.description).toBe('Manage conversation history.');
+    expect(chatCommand.subCommands).toHaveLength(3);
+  });
+
+  describe('list subcommand', () => {
+    let listCommand: SlashCommand;
+
+    beforeEach(() => {
+      listCommand = getSubCommand('list');
+    });
+
+    it('should inform when no checkpoints are found', async () => {
+      mockFs.readdir.mockImplementation(
+        (async (_: string): Promise<string[]> =>
+          [] as string[]) as unknown as typeof fsPromises.readdir,
+      );
+      const result = await listCommand?.action?.(mockContext, '');
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'info',
+        content: 'No saved conversation checkpoints found.',
+      });
+    });
+
+    it('should list found checkpoints', async () => {
+      const fakeFiles = ['checkpoint-test1.json', 'checkpoint-test2.json'];
+      const date = new Date();
+
+      mockFs.readdir.mockImplementation(
+        (async (_: string): Promise<string[]> =>
+          fakeFiles as string[]) as unknown as typeof fsPromises.readdir,
+      );
+      mockFs.stat.mockImplementation((async (path: string): Promise<Stats> => {
+        if (path.endsWith('test1.json')) {
+          return { mtime: date } as Stats;
+        }
+        return { mtime: new Date(date.getTime() + 1000) } as Stats;
+      }) as unknown as typeof fsPromises.stat);
+
+      const result = (await listCommand?.action?.(
+        mockContext,
+        '',
+      )) as MessageActionReturn;
+
+      const content = result?.content ?? '';
+      expect(result?.type).toBe('message');
+      expect(content).toContain('List of saved conversations:');
+      const index1 = content.indexOf('- \u001b[36mtest1\u001b[0m');
+      const index2 = content.indexOf('- \u001b[36mtest2\u001b[0m');
+      expect(index1).toBeGreaterThanOrEqual(0);
+      expect(index2).toBeGreaterThan(index1);
+    });
+  });
+  describe('save subcommand', () => {
+    let saveCommand: SlashCommand;
+    const tag = 'my-tag';
+    beforeEach(() => {
+      saveCommand = getSubCommand('save');
+    });
+
+    it('should return an error if tag is missing', async () => {
+      const result = await saveCommand?.action?.(mockContext, '  ');
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'error',
+        content: 'Missing tag. Usage: /chat save <tag>',
+      });
+    });
+
+    it('should inform if conversation history is empty', async () => {
+      mockGetHistory.mockReturnValue([]);
+      const result = await saveCommand?.action?.(mockContext, tag);
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'info',
+        content: 'No conversation found to save.',
+      });
+    });
+
+    it('should save the conversation', async () => {
+      const history: HistoryItemWithoutId[] = [
+        {
+          type: 'user',
+          text: 'hello',
+        },
+      ];
+      mockGetHistory.mockReturnValue(history);
+      const result = await saveCommand?.action?.(mockContext, tag);
+
+      expect(mockSaveCheckpoint).toHaveBeenCalledWith(history, tag);
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'info',
+        content: `Conversation checkpoint saved with tag: ${tag}.`,
+      });
+    });
+  });
+
+  describe('resume subcommand', () => {
+    const goodTag = 'good-tag';
+    const badTag = 'bad-tag';
+
+    let resumeCommand: SlashCommand;
+    beforeEach(() => {
+      resumeCommand = getSubCommand('resume');
+    });
+
+    it('should return an error if tag is missing', async () => {
+      const result = await resumeCommand?.action?.(mockContext, '');
+
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'error',
+        content: 'Missing tag. Usage: /chat resume <tag>',
+      });
+    });
+
+    it('should inform if checkpoint is not found', async () => {
+      mockLoadCheckpoint.mockResolvedValue([]);
+
+      const result = await resumeCommand?.action?.(mockContext, badTag);
+
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'info',
+        content: `No saved checkpoint found with tag: ${badTag}.`,
+      });
+    });
+
+    it('should resume a conversation', async () => {
+      const conversation: Content[] = [
+        { role: 'user', parts: [{ text: 'hello gemini' }] },
+        { role: 'model', parts: [{ text: 'hello world' }] },
+      ];
+      mockLoadCheckpoint.mockResolvedValue(conversation);
+
+      const result = await resumeCommand?.action?.(mockContext, goodTag);
+
+      expect(result).toEqual({
+        type: 'load_history',
+        history: [
+          { type: 'user', text: 'hello gemini' },
+          { type: 'gemini', text: 'hello world' },
+        ] as HistoryItemWithoutId[],
+        clientHistory: conversation,
+      });
+    });
+
+    describe('completion', () => {
+      it('should provide completion suggestions', async () => {
+        const fakeFiles = ['checkpoint-alpha.json', 'checkpoint-beta.json'];
+        mockFs.readdir.mockImplementation(
+          (async (_: string): Promise<string[]> =>
+            fakeFiles as string[]) as unknown as typeof fsPromises.readdir,
+        );
+
+        mockFs.stat.mockImplementation(
+          (async (_: string): Promise<Stats> =>
+            ({
+              mtime: new Date(),
+            }) as Stats) as unknown as typeof fsPromises.stat,
+        );
+
+        const result = await resumeCommand?.completion?.(mockContext, 'a');
+
+        expect(result).toEqual(['alpha']);
+      });
+
+      it('should suggest filenames sorted by modified time (newest first)', async () => {
+        const fakeFiles = ['checkpoint-test1.json', 'checkpoint-test2.json'];
+        const date = new Date();
+        mockFs.readdir.mockImplementation(
+          (async (_: string): Promise<string[]> =>
+            fakeFiles as string[]) as unknown as typeof fsPromises.readdir,
+        );
+        mockFs.stat.mockImplementation((async (
+          path: string,
+        ): Promise<Stats> => {
+          if (path.endsWith('test1.json')) {
+            return { mtime: date } as Stats;
+          }
+          return { mtime: new Date(date.getTime() + 1000) } as Stats;
+        }) as unknown as typeof fsPromises.stat);
+
+        const result = await resumeCommand?.completion?.(mockContext, '');
+        // Sort items by last modified time (newest first)
+        expect(result).toEqual(['test2', 'test1']);
+      });
+    });
+  });
+});