feat(cli): add chat resume footer on session quit (#20667)

Co-authored-by: Dev Randalpura <devrandalpura@google.com>

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

@@ -5,11 +5,23 @@
  */
 
 import { renderWithProviders } from '../../test-utils/render.js';
-import { describe, it, expect, vi } from 'vitest';
+import { describe, it, expect, vi, beforeEach } from 'vitest';
 import { SessionSummaryDisplay } from './SessionSummaryDisplay.js';
 import * as SessionContext from '../contexts/SessionContext.js';
 import type { SessionMetrics } from '../contexts/SessionContext.js';
-import { ToolCallDecision } from '@google/gemini-cli-core';
+import {
+  ToolCallDecision,
+  getShellConfiguration,
+} from '@google/gemini-cli-core';
+
+vi.mock('@google/gemini-cli-core', async (importOriginal) => {
+  const actual =
+    await importOriginal<typeof import('@google/gemini-cli-core')>();
+  return {
+    ...actual,
+    getShellConfiguration: vi.fn(),
+  };
+});
 
 vi.mock('../contexts/SessionContext.js', async (importOriginal) => {
   const actual = await importOriginal<typeof SessionContext>();
@@ -19,12 +31,16 @@ vi.mock('../contexts/SessionContext.js', async (importOriginal) => {
   };
 });
 
+const getShellConfigurationMock = vi.mocked(getShellConfiguration);
 const useSessionStatsMock = vi.mocked(SessionContext.useSessionStats);
 
-const renderWithMockedStats = async (metrics: SessionMetrics) => {
+const renderWithMockedStats = async (
+  metrics: SessionMetrics,
+  sessionId = 'test-session',
+) => {
   useSessionStatsMock.mockReturnValue({
     stats: {
-      sessionId: 'test-session',
+      sessionId,
       sessionStartTime: new Date(),
       metrics,
       lastPromptTokenCount: 0,
@@ -46,8 +62,38 @@ const renderWithMockedStats = async (metrics: SessionMetrics) => {
 };
 
 describe('<SessionSummaryDisplay />', () => {
+  const emptyMetrics: SessionMetrics = {
+    models: {},
+    tools: {
+      totalCalls: 0,
+      totalSuccess: 0,
+      totalFail: 0,
+      totalDurationMs: 0,
+      totalDecisions: {
+        accept: 0,
+        reject: 0,
+        modify: 0,
+        [ToolCallDecision.AUTO_ACCEPT]: 0,
+      },
+      byName: {},
+    },
+    files: {
+      totalLinesAdded: 0,
+      totalLinesRemoved: 0,
+    },
+  };
+
+  beforeEach(() => {
+    getShellConfigurationMock.mockReturnValue({
+      executable: 'bash',
+      argsPrefix: ['-c'],
+      shell: 'bash',
+    });
+  });
+
   it('renders the summary display with a title', async () => {
     const metrics: SessionMetrics = {
+      ...emptyMetrics,
       models: {
         'gemini-2.5-pro': {
           api: { totalRequests: 10, totalErrors: 1, totalLatencyMs: 50234 },
@@ -63,19 +109,6 @@ describe('<SessionSummaryDisplay />', () => {
           roles: {},
         },
       },
-      tools: {
-        totalCalls: 0,
-        totalSuccess: 0,
-        totalFail: 0,
-        totalDurationMs: 0,
-        totalDecisions: {
-          accept: 0,
-          reject: 0,
-          modify: 0,
-          [ToolCallDecision.AUTO_ACCEPT]: 0,
-        },
-        byName: {},
-      },
       files: {
         totalLinesAdded: 42,
         totalLinesRemoved: 15,
@@ -89,4 +122,70 @@ describe('<SessionSummaryDisplay />', () => {
     expect(output).toMatchSnapshot();
     unmount();
   });
+
+  describe('Session ID escaping', () => {
+    it('renders a standard UUID-formatted session ID in the footer (bash)', async () => {
+      const uuidSessionId = '1234-abcd-5678-efgh';
+      const { lastFrame, unmount } = await renderWithMockedStats(
+        emptyMetrics,
+        uuidSessionId,
+      );
+      const output = lastFrame();
+
+      // Standard UUID characters should not be escaped/quoted by default for bash.
+      expect(output).toContain('gemini --resume 1234-abcd-5678-efgh');
+      unmount();
+    });
+
+    it('sanitizes a malicious session ID in the footer (bash)', async () => {
+      const maliciousSessionId = "'; rm -rf / #";
+      const { lastFrame, unmount } = await renderWithMockedStats(
+        emptyMetrics,
+        maliciousSessionId,
+      );
+      const output = lastFrame();
+
+      // escapeShellArg (using shell-quote for bash) will wrap special characters in double quotes.
+      expect(output).toContain('gemini --resume "\'; rm -rf / #"');
+      unmount();
+    });
+
+    it('renders a standard UUID-formatted session ID in the footer (powershell)', async () => {
+      getShellConfigurationMock.mockReturnValue({
+        executable: 'powershell.exe',
+        argsPrefix: ['-NoProfile', '-Command'],
+        shell: 'powershell',
+      });
+
+      const uuidSessionId = '1234-abcd-5678-efgh';
+      const { lastFrame, unmount } = await renderWithMockedStats(
+        emptyMetrics,
+        uuidSessionId,
+      );
+      const output = lastFrame();
+
+      // PowerShell wraps strings in single quotes
+      expect(output).toContain("gemini --resume '1234-abcd-5678-efgh'");
+      unmount();
+    });
+
+    it('sanitizes a malicious session ID in the footer (powershell)', async () => {
+      getShellConfigurationMock.mockReturnValue({
+        executable: 'powershell.exe',
+        argsPrefix: ['-NoProfile', '-Command'],
+        shell: 'powershell',
+      });
+
+      const maliciousSessionId = "'; rm -rf / #";
+      const { lastFrame, unmount } = await renderWithMockedStats(
+        emptyMetrics,
+        maliciousSessionId,
+      );
+      const output = lastFrame();
+
+      // PowerShell wraps in single quotes and escapes internal single quotes by doubling them
+      expect(output).toContain("gemini --resume '''; rm -rf / #'");
+      unmount();
+    });
+  });
 });

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

@@ -6,6 +6,8 @@
 
 import type React from 'react';
 import { StatsDisplay } from './StatsDisplay.js';
+import { useSessionStats } from '../contexts/SessionContext.js';
+import { escapeShellArg, getShellConfiguration } from '@google/gemini-cli-core';
 
 interface SessionSummaryDisplayProps {
   duration: string;
@@ -13,10 +15,16 @@ interface SessionSummaryDisplayProps {
 
 export const SessionSummaryDisplay: React.FC<SessionSummaryDisplayProps> = ({
   duration,
-}) => (
-  <StatsDisplay
-    title="Agent powering down. Goodbye!"
-    duration={duration}
-    footer="Tip: Resume a previous session using gemini --resume or /resume"
-  />
-);
+}) => {
+  const { stats } = useSessionStats();
+  const { shell } = getShellConfiguration();
+  const footer = `To resume this session: gemini --resume ${escapeShellArg(stats.sessionId, shell)}`;
+
+  return (
+    <StatsDisplay
+      title="Agent powering down. Goodbye!"
+      duration={duration}
+      footer={footer}
+    />
+  );
+};

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

@@ -24,7 +24,7 @@ exports[`<SessionSummaryDisplay /> > renders the summary display with a title 1`
 │                                                                                                  │
 │  Savings Highlight: 500 (50.0%) of input tokens were served from the cache, reducing costs.      │
 │                                                                                                  │
-│  Tip: Resume a previous session using gemini --resume or /resume                                 │
+│  To resume this session: gemini --resume test-session                                            │
 ╰──────────────────────────────────────────────────────────────────────────────────────────────────╯
 "
 `;