feat: メニュー選択を数字入力からカーソル（上下キー）方式に変更

src/__tests__/prompt.test.ts

@@ -0,0 +1,319 @@
+/**
+ * Tests for prompt module (cursor-based interactive menu)
+ */
+
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import chalk from 'chalk';
+import type { SelectOptionItem, KeyInputResult } from '../prompt/index.js';
+import { renderMenu, countRenderedLines, handleKeyInput } from '../prompt/index.js';
+
+// Disable chalk colors for predictable test output
+chalk.level = 0;
+
+describe('prompt', () => {
+  describe('renderMenu', () => {
+    const basicOptions: SelectOptionItem<string>[] = [
+      { label: 'Option A', value: 'a' },
+      { label: 'Option B', value: 'b' },
+      { label: 'Option C', value: 'c' },
+    ];
+
+    it('should render all options with cursor on selected item', () => {
+      const lines = renderMenu(basicOptions, 0, false);
+
+      // 3 options = 3 lines
+      expect(lines).toHaveLength(3);
+      // First item selected - contains cursor marker
+      expect(lines[0]).toContain('❯');
+      expect(lines[0]).toContain('Option A');
+      // Other items should not have cursor
+      expect(lines[1]).not.toContain('❯');
+      expect(lines[2]).not.toContain('❯');
+    });
+
+    it('should move cursor to second item when selectedIndex is 1', () => {
+      const lines = renderMenu(basicOptions, 1, false);
+
+      expect(lines[0]).not.toContain('❯');
+      expect(lines[1]).toContain('❯');
+      expect(lines[1]).toContain('Option B');
+      expect(lines[2]).not.toContain('❯');
+    });
+
+    it('should move cursor to last item', () => {
+      const lines = renderMenu(basicOptions, 2, false);
+
+      expect(lines[0]).not.toContain('❯');
+      expect(lines[1]).not.toContain('❯');
+      expect(lines[2]).toContain('❯');
+      expect(lines[2]).toContain('Option C');
+    });
+
+    it('should include Cancel option when hasCancelOption is true', () => {
+      const lines = renderMenu(basicOptions, 0, true);
+
+      // 3 options + 1 cancel = 4 lines
+      expect(lines).toHaveLength(4);
+      expect(lines[3]).toContain('Cancel');
+    });
+
+    it('should highlight Cancel when it is selected', () => {
+      const lines = renderMenu(basicOptions, 3, true);
+
+      // Cancel is at index 3 (options.length)
+      expect(lines[3]).toContain('❯');
+      expect(lines[3]).toContain('Cancel');
+      // Other items should not have cursor
+      expect(lines[0]).not.toContain('❯');
+      expect(lines[1]).not.toContain('❯');
+      expect(lines[2]).not.toContain('❯');
+    });
+
+    it('should render description lines', () => {
+      const optionsWithDesc: SelectOptionItem<string>[] = [
+        { label: 'Option A', value: 'a', description: 'Description for A' },
+        { label: 'Option B', value: 'b' },
+      ];
+
+      const lines = renderMenu(optionsWithDesc, 0, false);
+
+      // Option A has label + description = 2 lines, Option B = 1 line
+      expect(lines).toHaveLength(3);
+      expect(lines[1]).toContain('Description for A');
+    });
+
+    it('should render detail lines', () => {
+      const optionsWithDetails: SelectOptionItem<string>[] = [
+        {
+          label: 'Option A',
+          value: 'a',
+          description: 'Desc A',
+          details: ['Detail 1', 'Detail 2'],
+        },
+        { label: 'Option B', value: 'b' },
+      ];
+
+      const lines = renderMenu(optionsWithDetails, 0, false);
+
+      // Option A: label + description + 2 details = 4 lines, Option B = 1 line
+      expect(lines).toHaveLength(5);
+      expect(lines[2]).toContain('Detail 1');
+      expect(lines[3]).toContain('Detail 2');
+    });
+
+    it('should handle empty options array', () => {
+      const lines = renderMenu([], 0, false);
+      expect(lines).toHaveLength(0);
+    });
+
+    it('should handle empty options with cancel', () => {
+      const lines = renderMenu([], 0, true);
+      expect(lines).toHaveLength(1);
+      expect(lines[0]).toContain('Cancel');
+    });
+  });
+
+  describe('countRenderedLines', () => {
+    it('should count basic options (1 line each)', () => {
+      const options: SelectOptionItem<string>[] = [
+        { label: 'A', value: 'a' },
+        { label: 'B', value: 'b' },
+        { label: 'C', value: 'c' },
+      ];
+
+      expect(countRenderedLines(options, false)).toBe(3);
+    });
+
+    it('should add 1 for cancel option', () => {
+      const options: SelectOptionItem<string>[] = [
+        { label: 'A', value: 'a' },
+        { label: 'B', value: 'b' },
+      ];
+
+      expect(countRenderedLines(options, true)).toBe(3);
+    });
+
+    it('should count description lines', () => {
+      const options: SelectOptionItem<string>[] = [
+        { label: 'A', value: 'a', description: 'Desc A' },
+        { label: 'B', value: 'b' },
+      ];
+
+      // A: label + desc = 2, B: label = 1, total = 3
+      expect(countRenderedLines(options, false)).toBe(3);
+    });
+
+    it('should count detail lines', () => {
+      const options: SelectOptionItem<string>[] = [
+        {
+          label: 'A',
+          value: 'a',
+          description: 'Desc',
+          details: ['D1', 'D2', 'D3'],
+        },
+      ];
+
+      // label + desc + 3 details = 5
+      expect(countRenderedLines(options, false)).toBe(5);
+    });
+
+    it('should count combined description and details with cancel', () => {
+      const options: SelectOptionItem<string>[] = [
+        {
+          label: 'A',
+          value: 'a',
+          description: 'Desc A',
+          details: ['D1'],
+        },
+        { label: 'B', value: 'b', description: 'Desc B' },
+      ];
+
+      // A: 1 + 1 + 1 = 3, B: 1 + 1 = 2, cancel: 1, total = 6
+      expect(countRenderedLines(options, true)).toBe(6);
+    });
+
+    it('should return 0 for empty options without cancel', () => {
+      expect(countRenderedLines([], false)).toBe(0);
+    });
+
+    it('should return 1 for empty options with cancel', () => {
+      expect(countRenderedLines([], true)).toBe(1);
+    });
+  });
+
+  describe('handleKeyInput', () => {
+    // 3 options + cancel = 4 total items
+    const totalItems = 4;
+    const optionCount = 3;
+    const hasCancelOption = true;
+
+    describe('move up (arrow up / k)', () => {
+      it('should move up with arrow key', () => {
+        const result = handleKeyInput('\x1B[A', 1, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 0 });
+      });
+
+      it('should move up with vim k key', () => {
+        const result = handleKeyInput('k', 2, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 1 });
+      });
+
+      it('should wrap around from first item to last', () => {
+        const result = handleKeyInput('\x1B[A', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 3 });
+      });
+    });
+
+    describe('move down (arrow down / j)', () => {
+      it('should move down with arrow key', () => {
+        const result = handleKeyInput('\x1B[B', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 1 });
+      });
+
+      it('should move down with vim j key', () => {
+        const result = handleKeyInput('j', 1, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 2 });
+      });
+
+      it('should wrap around from last item to first', () => {
+        const result = handleKeyInput('\x1B[B', 3, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 0 });
+      });
+    });
+
+    describe('confirm (Enter)', () => {
+      it('should confirm with carriage return', () => {
+        const result = handleKeyInput('\r', 2, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'confirm', selectedIndex: 2 });
+      });
+
+      it('should confirm with newline', () => {
+        const result = handleKeyInput('\n', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'confirm', selectedIndex: 0 });
+      });
+
+      it('should confirm cancel position when Enter on cancel item', () => {
+        const result = handleKeyInput('\r', 3, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'confirm', selectedIndex: 3 });
+      });
+    });
+
+    describe('cancel (Escape)', () => {
+      it('should return optionCount as cancelIndex when hasCancelOption', () => {
+        const result = handleKeyInput('\x1B', 1, totalItems, true, optionCount);
+        expect(result).toEqual({ action: 'cancel', cancelIndex: 3 });
+      });
+
+      it('should return -1 as cancelIndex when no cancel option', () => {
+        const result = handleKeyInput('\x1B', 1, 3, false, optionCount);
+        expect(result).toEqual({ action: 'cancel', cancelIndex: -1 });
+      });
+    });
+
+    describe('exit (Ctrl+C)', () => {
+      it('should return exit action', () => {
+        const result = handleKeyInput('\x03', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'exit' });
+      });
+    });
+
+    describe('unrecognized keys', () => {
+      it('should return none for regular characters', () => {
+        const result = handleKeyInput('a', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'none' });
+      });
+
+      it('should return none for space', () => {
+        const result = handleKeyInput(' ', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'none' });
+      });
+
+      it('should return none for numbers', () => {
+        const result = handleKeyInput('1', 0, totalItems, hasCancelOption, optionCount);
+        expect(result).toEqual({ action: 'none' });
+      });
+    });
+
+    describe('without cancel option', () => {
+      const noCancelTotal = 3;
+
+      it('should wrap up correctly without cancel', () => {
+        const result = handleKeyInput('\x1B[A', 0, noCancelTotal, false, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 2 });
+      });
+
+      it('should wrap down correctly without cancel', () => {
+        const result = handleKeyInput('\x1B[B', 2, noCancelTotal, false, optionCount);
+        expect(result).toEqual({ action: 'move', newIndex: 0 });
+      });
+    });
+
+    describe('single option', () => {
+      it('should wrap around with 1 item + cancel (totalItems=2)', () => {
+        const result = handleKeyInput('\x1B[B', 1, 2, true, 1);
+        expect(result).toEqual({ action: 'move', newIndex: 0 });
+      });
+
+      it('should confirm single option', () => {
+        const result = handleKeyInput('\r', 0, 1, false, 1);
+        expect(result).toEqual({ action: 'confirm', selectedIndex: 0 });
+      });
+    });
+  });
+
+  describe('selectOption', () => {
+    it('should return null for empty options', async () => {
+      const { selectOption } = await import('../prompt/index.js');
+      const result = await selectOption('Test:', []);
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('selectOptionWithDefault', () => {
+    it('should return default for empty options', async () => {
+      const { selectOptionWithDefault } = await import('../prompt/index.js');
+      const result = await selectOptionWithDefault('Test:', [], 'fallback');
+      expect(result).toBe('fallback');
+    });
+  });
+});

src/prompt/index.ts

@@ -1,68 +1,250 @@
 /**
  * Interactive prompts for CLI
  *
- * Provides simple input prompts for user interaction.
+ * Provides cursor-based selection menus using arrow keys.
+ * Users navigate with ↑/↓ keys and confirm with Enter.
  */
 
 import * as readline from 'node:readline';
 import chalk from 'chalk';
 
+/** Option type for selectOption */
+export interface SelectOptionItem<T extends string> {
+  label: string;
+  value: T;
+  description?: string;
+  details?: string[];
+}
+
 /**
- * Prompt user to select from a list of options
+ * Render the menu options to the terminal.
+ * Writes directly to stdout using ANSI escape codes.
+ * Exported for testing.
+ */
+export function renderMenu<T extends string>(
+  options: SelectOptionItem<T>[],
+  selectedIndex: number,
+  hasCancelOption: boolean
+): string[] {
+  const lines: string[] = [];
+
+  for (let i = 0; i < options.length; i++) {
+    const opt = options[i]!;
+    const isSelected = i === selectedIndex;
+    const cursor = isSelected ? chalk.cyan('❯') : ' ';
+    const label = isSelected ? chalk.cyan.bold(opt.label) : opt.label;
+    lines.push(`  ${cursor} ${label}`);
+
+    if (opt.description) {
+      lines.push(chalk.gray(`     ${opt.description}`));
+    }
+    if (opt.details && opt.details.length > 0) {
+      for (const detail of opt.details) {
+        lines.push(chalk.dim(`       • ${detail}`));
+      }
+    }
+  }
+
+  if (hasCancelOption) {
+    const isCancelSelected = selectedIndex === options.length;
+    const cursor = isCancelSelected ? chalk.cyan('❯') : ' ';
+    const label = isCancelSelected ? chalk.cyan.bold('Cancel') : chalk.gray('Cancel');
+    lines.push(`  ${cursor} ${label}`);
+  }
+
+  return lines;
+}
+
+/**
+ * Count total rendered lines for a set of options.
+ * Exported for testing.
+ */
+export function countRenderedLines<T extends string>(
+  options: SelectOptionItem<T>[],
+  hasCancelOption: boolean
+): number {
+  let count = 0;
+  for (const opt of options) {
+    count++; // main label line
+    if (opt.description) count++;
+    if (opt.details) count += opt.details.length;
+  }
+  if (hasCancelOption) count++;
+  return count;
+}
+
+/** Result of handling a key input */
+export type KeyInputResult =
+  | { action: 'move'; newIndex: number }
+  | { action: 'confirm'; selectedIndex: number }
+  | { action: 'cancel'; cancelIndex: number }
+  | { action: 'exit' }
+  | { action: 'none' };
+
+/**
+ * Pure function for key input state transitions.
+ * Maps a key string to an action and new state.
+ * Exported for testing.
+ */
+export function handleKeyInput(
+  key: string,
+  currentIndex: number,
+  totalItems: number,
+  hasCancelOption: boolean,
+  optionCount: number
+): KeyInputResult {
+  // Up arrow or vim 'k'
+  if (key === '\x1B[A' || key === 'k') {
+    return { action: 'move', newIndex: (currentIndex - 1 + totalItems) % totalItems };
+  }
+  // Down arrow or vim 'j'
+  if (key === '\x1B[B' || key === 'j') {
+    return { action: 'move', newIndex: (currentIndex + 1) % totalItems };
+  }
+  // Enter
+  if (key === '\r' || key === '\n') {
+    return { action: 'confirm', selectedIndex: currentIndex };
+  }
+  // Ctrl+C - exit process
+  if (key === '\x03') {
+    return { action: 'exit' };
+  }
+  // Escape - cancel
+  if (key === '\x1B') {
+    return { action: 'cancel', cancelIndex: hasCancelOption ? optionCount : -1 };
+  }
+  return { action: 'none' };
+}
+
+/**
+ * Print the menu header (message + hint).
+ */
+function printHeader(message: string): void {
+  console.log();
+  console.log(chalk.cyan(message));
+  console.log(chalk.gray('  (↑↓ to move, Enter to select)'));
+  console.log();
+}
+
+/**
+ * Set up raw mode on stdin and return cleanup function.
+ */
+function setupRawMode(): { cleanup: (listener: (data: Buffer) => void) => void; wasRaw: boolean } {
+  const wasRaw = process.stdin.isRaw;
+  process.stdin.setRawMode(true);
+  process.stdin.resume();
+
+  return {
+    wasRaw,
+    cleanup(listener: (data: Buffer) => void): void {
+      process.stdin.removeListener('data', listener);
+      process.stdin.setRawMode(wasRaw ?? false);
+      process.stdin.pause();
+    },
+  };
+}
+
+/**
+ * Redraw the menu by moving cursor up and re-rendering.
+ */
+function redrawMenu<T extends string>(
+  options: SelectOptionItem<T>[],
+  selectedIndex: number,
+  hasCancelOption: boolean,
+  totalLines: number
+): void {
+  process.stdout.write(`\x1B[${totalLines}A`);
+  process.stdout.write('\x1B[J');
+  const newLines = renderMenu(options, selectedIndex, hasCancelOption);
+  process.stdout.write(newLines.join('\n') + '\n');
+}
+
+/**
+ * Interactive cursor-based menu selection.
+ * Uses raw mode to capture arrow key input for navigation.
+ */
+function interactiveSelect<T extends string>(
+  message: string,
+  options: SelectOptionItem<T>[],
+  initialIndex: number,
+  hasCancelOption: boolean
+): Promise<number> {
+  return new Promise((resolve) => {
+    const totalItems = hasCancelOption ? options.length + 1 : options.length;
+    let selectedIndex = initialIndex;
+
+    printHeader(message);
+
+    const totalLines = countRenderedLines(options, hasCancelOption);
+    const lines = renderMenu(options, selectedIndex, hasCancelOption);
+    process.stdout.write(lines.join('\n') + '\n');
+
+    if (!process.stdin.isTTY) {
+      resolve(initialIndex);
+      return;
+    }
+
+    const rawMode = setupRawMode();
+
+    const onKeypress = (data: Buffer): void => {
+      const result = handleKeyInput(
+        data.toString(),
+        selectedIndex,
+        totalItems,
+        hasCancelOption,
+        options.length
+      );
+
+      switch (result.action) {
+        case 'move':
+          selectedIndex = result.newIndex;
+          redrawMenu(options, selectedIndex, hasCancelOption, totalLines);
+          break;
+        case 'confirm':
+          rawMode.cleanup(onKeypress);
+          resolve(result.selectedIndex);
+          break;
+        case 'cancel':
+          rawMode.cleanup(onKeypress);
+          resolve(result.cancelIndex);
+          break;
+        case 'exit':
+          rawMode.cleanup(onKeypress);
+          process.exit(130);
+          break;
+        case 'none':
+          break;
+      }
+    };
+
+    process.stdin.on('data', onKeypress);
+  });
+}
+
+/**
+ * Prompt user to select from a list of options using cursor navigation.
  * @returns Selected option or null if cancelled
  */
 export async function selectOption<T extends string>(
   message: string,
-  options: { label: string; value: T; description?: string; details?: string[] }[]
+  options: SelectOptionItem<T>[]
 ): Promise<T | null> {
-  const rl = readline.createInterface({
+  if (options.length === 0) return null;
-    input: process.stdin,
-    output: process.stdout,
-  });
 
-  console.log();
+  const selectedIndex = await interactiveSelect(message, options, 0, true);
-  console.log(chalk.cyan(message));
-  console.log();
 
-  options.forEach((opt, idx) => {
+  // Cancel selected (last item or escape)
-    console.log(chalk.yellow(`  ${idx + 1}. `) + opt.label);
+  if (selectedIndex === options.length || selectedIndex === -1) {
-    // Display description if provided
+    return null;
-    if (opt.description) {
-      console.log(chalk.gray(`     ${opt.description}`));
-    }
-    // Display additional details if provided
-    if (opt.details && opt.details.length > 0) {
-      opt.details.forEach((detail) => {
-        console.log(chalk.dim(`       • ${detail}`));
-      });
-    }
-  });
-  console.log(chalk.gray(`  0. Cancel`));
-  console.log();
-
-  return new Promise((resolve) => {
-    rl.question(chalk.green('Select [0-' + options.length + ']: '), (answer) => {
-      rl.close();
-
-      const num = parseInt(answer.trim(), 10);
-
-      if (isNaN(num) || num === 0) {
-        resolve(null);
-        return;
   }
 
-      if (num >= 1 && num <= options.length) {
+  const selected = options[selectedIndex];
-        const selected = options[num - 1];
   if (selected) {
-          resolve(selected.value);
+    console.log(chalk.green(`  ✓ ${selected.label}`));
-          return;
+    return selected.value;
-        }
   }
 
-      console.log(chalk.red('Invalid selection'));
+  return null;
-      resolve(null);
-    });
-  });
 }
 
 /**
@@ -91,8 +273,8 @@ export async function promptInput(message: string): Promise<string | null> {
 }
 
 /**
- * Prompt user to select from a list of options with a default value
+ * Prompt user to select from a list of options with a default value.
- * User can press Enter to select default, or enter a number to select specific option
+ * Uses cursor navigation. Enter immediately selects the default.
  * @returns Selected option value
  */
 export async function selectOptionWithDefault<T extends string>(
@@ -100,53 +282,33 @@ export async function selectOptionWithDefault<T extends string>(
   options: { label: string; value: T }[],
   defaultValue: T
 ): Promise<T> {
-  const rl = readline.createInterface({
+  if (options.length === 0) return defaultValue;
-    input: process.stdin,
-    output: process.stdout,
-  });
-
-  console.log();
-  console.log(chalk.cyan(message));
-  console.log();
 
+  // Find default index
   const defaultIndex = options.findIndex((opt) => opt.value === defaultValue);
+  const initialIndex = defaultIndex >= 0 ? defaultIndex : 0;
 
-  options.forEach((opt, idx) => {
+  // Mark default in label
-    const isDefault = opt.value === defaultValue;
+  const decoratedOptions: SelectOptionItem<T>[] = options.map((opt) => ({
-    const marker = isDefault ? chalk.green(' (default)') : '';
+    ...opt,
-    console.log(chalk.yellow(`  ${idx + 1}. `) + opt.label + marker);
+    label: opt.value === defaultValue ? `${opt.label} ${chalk.green('(default)')}` : opt.label,
-  });
+  }));
-  console.log();
 
-  const hint = defaultIndex >= 0 ? ` [Enter=${defaultIndex + 1}]` : '';
+  const selectedIndex = await interactiveSelect(message, decoratedOptions, initialIndex, false);
 
-  return new Promise((resolve) => {
+  // Escape pressed - use default
-    rl.question(chalk.green(`Select [1-${options.length}]${hint}: `), (answer) => {
+  if (selectedIndex === -1) {
-      rl.close();
+    console.log(chalk.gray(`  Using default: ${defaultValue}`));
-
+    return defaultValue;
-      const trimmed = answer.trim();
-
-      // Empty input = use default
-      if (!trimmed) {
-        resolve(defaultValue);
-        return;
   }
 
-      const num = parseInt(trimmed, 10);
+  const selected = options[selectedIndex];
-
-      if (num >= 1 && num <= options.length) {
-        const selected = options[num - 1];
   if (selected) {
-          resolve(selected.value);
+    console.log(chalk.green(`  ✓ ${selected.label}`));
-          return;
+    return selected.value;
-        }
   }
 
-      // Invalid input, use default
+  return defaultValue;
-      console.log(chalk.gray(`Invalid selection, using default: ${defaultValue}`));
-      resolve(defaultValue);
-    });
-  });
 }
 
 /**