Merge pull request #151 from MinKuanIsHere/313552009

[LAB2] 313552009

Author: AxelHowe

lab2/main_test.js

@@ -1,6 +1,156 @@
-const test = require('node:test');
-const assert = require('assert');
-const { Application, MailSystem } = require('./main');
+import fs from 'fs';
+import path from 'path';
+import os from 'os';
+import test from 'node:test';
+import assert from 'assert';
+import { Application, MailSystem } from './main.js';
 
-// TODO: write your tests here
-// Remember to use Stub, Mock, and Spy when necessary
+// 輔助函式：在暫存目錄中建立 name_list.txt，並切換工作目錄
+async function withTempNameList(fn) {
+  const originalCwd = process.cwd();
+  const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'lab2-'));
+  fs.writeFileSync(path.join(tmpDir, 'name_list.txt'), 'Alice\nBob\nCharlie');
+  process.chdir(tmpDir);
+  try {
+    await fn();
+  } finally {
+    process.chdir(originalCwd);
+    fs.rmSync(tmpDir, { recursive: true, force: true });
+  }
+}
+
+// 建立 Stub 輔助函式
+const createStub = (obj, method, implementation) => {
+  const original = obj[method];
+  obj[method] = implementation;
+  return { restore: () => { obj[method] = original; } };
+};
+
+// 測試 MailSystem.write()（不需要檔案）
+test('MailSystem.write should generate correct mail content', () => {
+  const mailSystem = new MailSystem();
+  const result = mailSystem.write('Alice');
+  assert.strictEqual(result, 'Congrats, Alice!');
+});
+
+// 測試 MailSystem.send()：透過 stub 控制隨機行為
+test('MailSystem.send should return success or failure', () => {
+  const mailSystem = new MailSystem();
+  const randomStub = createStub(Math, 'random', () => 0.9);
+  assert.strictEqual(mailSystem.send('Alice', 'Congrats, Alice!'), true);
+  randomStub.restore();
+  const randomStub2 = createStub(Math, 'random', () => 0.4);
+  assert.strictEqual(mailSystem.send('Alice', 'Congrats, Alice!'), false);
+  randomStub2.restore();
+});
+
+// 以下測試皆需要 name_list.txt，所以採用 withTempNameList 包裹
+
+test('Application.getNames should read and parse names from file', async () => {
+  await withTempNameList(async () => {
+    const app = new Application();
+    // 等待 constructor 的非同步初始化完成
+    await new Promise(resolve => setTimeout(resolve, 10));
+    const [people, selected] = await app.getNames();
+    assert.deepStrictEqual(people, ['Alice', 'Bob', 'Charlie']);
+    assert.deepStrictEqual(selected, []);
+  });
+});
+
+test('Application constructor should initialize people and selected', async () => {
+  await withTempNameList(async () => {
+    const app = new Application();
+    await new Promise(resolve => setTimeout(resolve, 10));
+    assert.deepStrictEqual(app.people, ['Alice', 'Bob', 'Charlie']);
+    assert.deepStrictEqual(app.selected, []);
+  });
+});
+
+test('Application.getRandomPerson should return a person from people list', async () => {
+  await withTempNameList(async () => {
+    const app = new Application();
+    await new Promise(resolve => setTimeout(resolve, 10));
+    // stub Math.random 固定回傳 0.5 (floor(0.5 * 3) = 1) → 'Bob'
+    const randomStub = createStub(Math, 'random', () => 0.5);
+    assert.strictEqual(app.getRandomPerson(), 'Bob');
+    randomStub.restore();
+  });
+});
+
+test('Application.selectNextPerson should select a unique person in order', async () => {
+  await withTempNameList(async () => {
+    const app = new Application();
+    await new Promise(resolve => setTimeout(resolve, 10));
+    // stub getRandomPerson 依序回傳：'Alice', 'Bob', 'Charlie'
+    let sequence = ['Alice', 'Bob', 'Charlie'];
+    let index = 0;
+    const stub = createStub(app, 'getRandomPerson', () => sequence[index++]);
+    
+    const selected1 = app.selectNextPerson();
+    assert.strictEqual(selected1, 'Alice');
+    assert.strictEqual(app.selected.length, 1);
+    
+    const selected2 = app.selectNextPerson();
+    assert.strictEqual(selected2, 'Bob');
+    assert.strictEqual(app.selected.length, 2);
+    
+    const selected3 = app.selectNextPerson();
+    assert.strictEqual(selected3, 'Charlie');
+    assert.strictEqual(app.selected.length, 3);
+    
+    const selected4 = app.selectNextPerson();
+    assert.strictEqual(selected4, null);
+    
+    stub.restore();
+  });
+});
+
+test('Application.selectNextPerson should retry if duplicate selected', async () => {
+  await withTempNameList(async () => {
+    const app = new Application();
+    await new Promise(resolve => setTimeout(resolve, 10));
+    // stub 模擬第一次回傳 'Alice'（已被選取），接著回傳 'Bob'
+    let callCount = 0;
+    const stub = createStub(app, 'getRandomPerson', () => {
+      if (callCount === 0) {
+        callCount++;
+        return 'Alice';
+      }
+      return 'Bob';
+    });
+    // 預先將 'Alice' 加入已選名單
+    app.selected = ['Alice'];
+    const result = app.selectNextPerson();
+    assert.strictEqual(result, 'Bob');
+    stub.restore();
+  });
+});
+
+test('Application.notifySelected should send mail to selected people', async () => {
+  await withTempNameList(async () => {
+    const app = new Application();
+    await new Promise(resolve => setTimeout(resolve, 10));
+    app.selected = ['Alice', 'Bob'];
+    let writeCalls = [];
+    let sendCalls = [];
+    const writeStub = createStub(app.mailSystem, 'write', (name) => {
+      writeCalls.push(name);
+      return `Congrats, ${name}!`;
+    });
+    const sendStub = createStub(app.mailSystem, 'send', (name, content) => {
+      sendCalls.push({ name, content });
+      return true;
+    });
+    
+    app.notifySelected();
+    
+    assert.deepStrictEqual(writeCalls, ['Alice', 'Bob']);
+    assert.deepStrictEqual(sendCalls, [
+      { name: 'Alice', content: 'Congrats, Alice!' },
+      { name: 'Bob', content: 'Congrats, Bob!' }
+    ]);
+    
+    writeStub.restore();
+    sendStub.restore();
+  });
+});