feat: add --show_memory_usage flag to display memory usage in status bar (#606)

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

@@ -7,16 +7,10 @@
 // packages/cli/src/config/config.test.ts
 
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
-// import * as fsPromises from 'fs/promises';
-// import * as fsSync from 'fs';
 import * as os from 'os';
-// import * as path from 'path'; // Unused, so removing
-// import { readPackageUp } from 'read-package-up';
-// import {
-//   loadHierarchicalGeminiMemory,
-// } from './config';
-// import { Settings } from './settings';
-// import * as ServerConfig from '@gemini-code/server';
+import { loadCliConfig } from './config.js';
+import { Settings } from './settings.js';
+import * as ServerConfig from '@gemini-code/server';
 
 const MOCK_HOME_DIR = '/mock/home/user';
 
@@ -28,7 +22,92 @@ vi.mock('os', async (importOriginal) => {
   };
 });
 
-// Further mocking of fs, read-package-up, etc. would go here if tests were active.
+vi.mock('read-package-up', () => ({
+  readPackageUp: vi.fn(() =>
+    Promise.resolve({ packageJson: { version: 'test-version' } }),
+  ),
+}));
+
+vi.mock('@gemini-code/server', async () => {
+  const actualServer = await vi.importActual<typeof ServerConfig>(
+    '@gemini-code/server',
+  );
+  return {
+    ...actualServer,
+    loadEnvironment: vi.fn(),
+    createServerConfig: vi.fn((params) => ({
+      // Mock the config object and its methods
+      getApiKey: () => params.apiKey,
+      getModel: () => params.model,
+      getSandbox: () => params.sandbox,
+      getTargetDir: () => params.targetDir,
+      getDebugMode: () => params.debugMode,
+      getQuestion: () => params.question,
+      getFullContext: () => params.fullContext,
+      getCoreTools: () => params.coreTools,
+      getToolDiscoveryCommand: () => params.toolDiscoveryCommand,
+      getToolCallCommand: () => params.toolCallCommand,
+      getMcpServerCommand: () => params.mcpServerCommand,
+      getMcpServers: () => params.mcpServers,
+      getUserAgent: () => params.userAgent,
+      getUserMemory: () => params.userMemory,
+      getGeminiMdFileCount: () => params.geminiMdFileCount,
+      getVertexAI: () => params.vertexai,
+      getShowMemoryUsage: () => params.showMemoryUsage, // Added for the test
+      // Add any other methods that are called on the config object
+      setUserMemory: vi.fn(),
+      setGeminiMdFileCount: vi.fn(),
+    })),
+    loadServerHierarchicalMemory: vi.fn(() =>
+      Promise.resolve({ memoryContent: '', fileCount: 0 }),
+    ),
+  };
+});
+
+describe('loadCliConfig', () => {
+  const originalArgv = process.argv;
+  const originalEnv = { ...process.env };
+
+  beforeEach(() => {
+    vi.resetAllMocks();
+    vi.mocked(os.homedir).mockReturnValue(MOCK_HOME_DIR);
+    process.env.GEMINI_API_KEY = 'test-api-key'; // Ensure API key is set for tests
+  });
+
+  afterEach(() => {
+    process.argv = originalArgv;
+    process.env = originalEnv;
+    vi.restoreAllMocks();
+  });
+
+  it('should set showMemoryUsage to true when --memory flag is present', async () => {
+    process.argv = ['node', 'script.js', '--show_memory_usage'];
+    const settings: Settings = {};
+    const config = await loadCliConfig(settings);
+    expect(config.getShowMemoryUsage()).toBe(true);
+  });
+
+  it('should set showMemoryUsage to false when --memory flag is not present', async () => {
+    process.argv = ['node', 'script.js'];
+    const settings: Settings = {};
+    const config = await loadCliConfig(settings);
+    expect(config.getShowMemoryUsage()).toBe(false);
+  });
+
+  it('should set showMemoryUsage to false by default from settings if CLI flag is not present', async () => {
+    process.argv = ['node', 'script.js'];
+    const settings: Settings = { showMemoryUsage: false };
+    const config = await loadCliConfig(settings);
+    expect(config.getShowMemoryUsage()).toBe(false);
+  });
+
+  it('should prioritize CLI flag over settings for showMemoryUsage (CLI true, settings false)', async () => {
+    process.argv = ['node', 'script.js', '--show_memory_usage'];
+    const settings: Settings = { showMemoryUsage: false };
+    const config = await loadCliConfig(settings);
+    expect(config.getShowMemoryUsage()).toBe(true);
+  });
+});
 
 describe('Hierarchical Memory Loading (config.ts) - Placeholder Suite', () => {
   beforeEach(() => {

packages/cli/src/config/config.ts

@@ -35,6 +35,7 @@ interface CliArgs {
   debug: boolean | undefined;
   prompt: string | undefined;
   all_files: boolean | undefined;
+  show_memory_usage: boolean | undefined;
 }
 
 async function parseArguments(): Promise<CliArgs> {
@@ -67,6 +68,11 @@ async function parseArguments(): Promise<CliArgs> {
       description: 'Include ALL files in context?',
       default: false,
     })
+    .option('show_memory_usage', {
+      type: 'boolean',
+      description: 'Show memory usage in status bar',
+      default: false,
+    })
     .help()
     .alias('h', 'help')
     .strict().argv;
@@ -152,6 +158,7 @@ export async function loadCliConfig(settings: Settings): Promise<Config> {
     userMemory: memoryContent,
     geminiMdFileCount: fileCount,
     vertexai: useVertexAI,
+    showMemoryUsage: argv.show_memory_usage || false,
   };
 
   return createServerConfig(configParams);

packages/cli/src/config/settings.ts

@@ -27,6 +27,7 @@ export interface Settings {
   toolCallCommand?: string;
   mcpServerCommand?: string;
   mcpServers?: Record<string, MCPServerConfig>;
+  showMemoryUsage?: boolean;
   // Add other settings here.
 }
 

packages/cli/src/ui/App.tsx

@@ -442,6 +442,9 @@ export const App = ({
             corgiMode={corgiMode}
             errorCount={errorCount}
             showErrorDetails={showErrorDetails}
+            showMemoryUsage={
+              config.getDebugMode() || config.getShowMemoryUsage()
+            }
           />
         </Box>
       </Box>

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

@@ -9,6 +9,8 @@ import { Box, Text } from 'ink';
 import { Colors } from '../colors.js';
 import { shortenPath, tildeifyPath } from '@gemini-code/server';
 import { ConsoleSummaryDisplay } from './ConsoleSummaryDisplay.js';
+import process from 'node:process';
+import { MemoryUsageDisplay } from './MemoryUsageDisplay.js';
 
 interface FooterProps {
   model: string;
@@ -20,6 +22,7 @@ interface FooterProps {
   corgiMode: boolean;
   errorCount: number;
   showErrorDetails: boolean;
+  showMemoryUsage?: boolean;
 }
 
 export const Footer: React.FC<FooterProps> = ({
@@ -31,6 +34,7 @@ export const Footer: React.FC<FooterProps> = ({
   corgiMode,
   errorCount,
   showErrorDetails,
+  showMemoryUsage,
 }) => (
   <Box marginTop={1} justifyContent="space-between" width="100%">
     <Box>
@@ -86,6 +90,7 @@ export const Footer: React.FC<FooterProps> = ({
           <ConsoleSummaryDisplay errorCount={errorCount} />
         </Box>
       )}
+      {showMemoryUsage && <MemoryUsageDisplay />}
     </Box>
   </Box>
 );

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

@@ -0,0 +1,40 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import React, { useEffect, useState } from 'react';
+import { Box, Text } from 'ink';
+import { Colors } from '../colors.js';
+import process from 'node:process';
+import { formatMemoryUsage } from '../utils/formatters.js';
+
+export const MemoryUsageDisplay: React.FC = () => {
+  const [memoryUsage, setMemoryUsage] = useState<string>('');
+  const [memoryUsageColor, setMemoryUsageColor] = useState<string>(
+    Colors.SubtleComment,
+  );
+
+  useEffect(() => {
+    const updateMemory = () => {
+      const usage = process.memoryUsage().rss;
+      setMemoryUsage(formatMemoryUsage(usage));
+      setMemoryUsageColor(
+        usage >= 2 * 1024 * 1024 * 1024
+          ? Colors.AccentRed
+          : Colors.SubtleComment,
+      );
+    };
+    const intervalId = setInterval(updateMemory, 2000);
+    updateMemory(); // Initial update
+    return () => clearInterval(intervalId);
+  }, []);
+
+  return (
+    <Box>
+      <Text color={Colors.SubtleComment}>| </Text>
+      <Text color={memoryUsageColor}>{memoryUsage}</Text>
+    </Box>
+  );
+};

packages/cli/src/ui/hooks/slashCommandProcessor.test.ts

@@ -9,9 +9,37 @@ const { mockProcessExit } = vi.hoisted(() => ({
 }));
 
 vi.mock('node:process', () => ({
+  default: {
+    exit: mockProcessExit,
+    cwd: vi.fn(() => '/mock/cwd'),
+    get env() {
+      return process.env;
+    }, // Use a getter to ensure current process.env is used
+    platform: 'test-platform',
+    version: 'test-node-version',
+    memoryUsage: vi.fn(() => ({
+      rss: 12345678,
+      heapTotal: 23456789,
+      heapUsed: 10234567,
+      external: 1234567,
+      arrayBuffers: 123456,
+    })),
+  },
+  // Provide top-level exports as well for compatibility
   exit: mockProcessExit,
   cwd: vi.fn(() => '/mock/cwd'),
-  env: { ...process.env },
+  get env() {
+    return process.env;
+  }, // Use a getter here too
+  platform: 'test-platform',
+  version: 'test-node-version',
+  memoryUsage: vi.fn(() => ({
+    rss: 12345678,
+    heapTotal: 23456789,
+    heapUsed: 10234567,
+    external: 1234567,
+    arrayBuffers: 123456,
+  })),
 }));
 
 vi.mock('node:fs/promises', () => ({
@@ -227,7 +255,7 @@ describe('useSlashCommandProcessor', () => {
       seatbeltProfileVar?: string,
     ) => {
       const cliVersion = 'test-version';
-      const osVersion = `${process.platform} ${process.version}`;
+      const osVersion = 'test-platform test-node-version';
       let sandboxEnvStr = 'no sandbox';
       if (sandboxEnvVar && sandboxEnvVar !== 'sandbox-exec') {
         sandboxEnvStr = sandboxEnvVar.replace(/^gemini-(?:code-)?/, '');
@@ -235,6 +263,8 @@ describe('useSlashCommandProcessor', () => {
         sandboxEnvStr = `sandbox-exec (${seatbeltProfileVar || 'unknown'})`;
       }
       const modelVersion = 'test-model';
+      // Use the mocked memoryUsage value
+      const memoryUsage = '11.8 MB';
 
       const diagnosticInfo = `
 ## Describe the bug
@@ -249,6 +279,7 @@ Add any other context about the problem here.
 *   **Operating System:** ${osVersion}
 *   **Sandbox Environment:** ${sandboxEnvStr}
 *   **Model Version:** ${modelVersion}
+*   **Memory Usage:** ${memoryUsage}
 `;
       let url =
         'https://github.com/google-gemini/gemini-cli/issues/new?template=bug_report.md';

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

@@ -7,11 +7,13 @@
 import { useCallback, useMemo } from 'react';
 import { type PartListUnion } from '@google/genai';
 import open from 'open';
+import process from 'node:process';
 import { UseHistoryManagerReturn } from './useHistoryManager.js';
 import { Config } from '@gemini-code/server';
 import { Message, MessageType, HistoryItemWithoutId } from '../types.js';
 import { createShowMemoryAction } from './useShowMemoryCommand.js';
 import { GIT_COMMIT_INFO } from '../../generated/git-commit.js';
+import { formatMemoryUsage } from '../utils/formatters.js';
 
 export interface SlashCommandActionReturn {
   shouldScheduleTool?: boolean;
@@ -206,6 +208,7 @@ export const useSlashCommandProcessor = (
             sandboxEnv = `sandbox-exec (${process.env.SEATBELT_PROFILE || 'unknown'})`;
           }
           const modelVersion = config?.getModel() || 'Unknown';
+          const memoryUsage = formatMemoryUsage(process.memoryUsage().rss);
 
           const diagnosticInfo = `
 ## Describe the bug
@@ -220,6 +223,7 @@ Add any other context about the problem here.
 *   **Operating System:** ${osVersion}
 *   **Sandbox Environment:** ${sandboxEnv}
 *   **Model Version:** ${modelVersion}
+*   **Memory Usage:** ${memoryUsage}
 `;
 
           let bugReportUrl =

packages/cli/src/ui/utils/formatters.ts

@@ -0,0 +1,16 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+export const formatMemoryUsage = (bytes: number): string => {
+  const gb = bytes / (1024 * 1024 * 1024);
+  if (bytes < 1024 * 1024) {
+    return `${(bytes / 1024).toFixed(1)} KB`;
+  }
+  if (bytes < 1024 * 1024 * 1024) {
+    return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
+  }
+  return `${gb.toFixed(2)} GB`;
+};

packages/server/src/config/config.ts

@@ -54,6 +54,7 @@ export interface ConfigParameters {
   geminiMdFileCount?: number;
   alwaysSkipModificationConfirmation?: boolean;
   vertexai?: boolean;
+  showMemoryUsage?: boolean;
 }
 
 export class Config {
@@ -75,6 +76,7 @@ export class Config {
   private geminiMdFileCount: number;
   private alwaysSkipModificationConfirmation: boolean;
   private readonly vertexai: boolean | undefined;
+  private readonly showMemoryUsage: boolean;
 
   constructor(params: ConfigParameters) {
     this.apiKey = params.apiKey;
@@ -95,6 +97,7 @@ export class Config {
     this.alwaysSkipModificationConfirmation =
       params.alwaysSkipModificationConfirmation ?? false;
     this.vertexai = params.vertexai;
+    this.showMemoryUsage = params.showMemoryUsage ?? false;
 
     this.toolRegistry = createToolRegistry(this);
   }
@@ -181,6 +184,10 @@ export class Config {
   getVertexAI(): boolean | undefined {
     return this.vertexai;
   }
+
+  getShowMemoryUsage(): boolean {
+    return this.showMemoryUsage;
+  }
 }
 
 function findEnvFile(startDir: string): string | null {