unit test lab2

lab2/main_test.js

@@ -1,6 +1,143 @@
 const test = require('node:test');
 const assert = require('assert');
+const fs = require('fs');
+const util = require('util');
+
+const readFile = util.promisify(fs.readFile);
+
 const { Application, MailSystem } = require('./main');
 
-// TODO: write your tests here
-// Remember to use Stub, Mock, and Spy when necessary
+function fileExists(filePath) {
+    try {
+        fs.accessSync(filePath, fs.constants.F_OK);
+        return true;
+    } catch (err) {
+        return false;
+    }
+}
+
+function createFile(fileName, disable) {
+    if (disable) return;
+    fs.writeFileSync(fileName, "Alice\nBob\nCharlie");
+}
+
+function deleteFile(fileName, disable) {
+    if (disable) return;
+    fs.unlinkSync(fileName);
+
+}
+
+const createApplication = async () => {
+    const existed = fileExists("name_list.txt");
+    createFile("name_list.txt", existed);
+
+    const app = new Application();
+
+    const data = await readFile('name_list.txt', 'utf8');
+    const people = data.split('\n');
+    const selected = [];
+    deleteFile("name_list.txt", existed);
+
+    app.people = people;
+    app.selected = selected;
+
+    return app;
+};
+
+test('Application - getRandomPerson', async (t) => {
+
+    await createApplication().then(app => {
+        assert.strictEqual(app.people.length, 3);
+
+        const randomPerson = app.getRandomPerson();
+        assert.ok(app.people.includes(randomPerson));
+    });
+
+});
+
+test('Application - getRandomPerson', async (t) => {
+
+    await createApplication().then(app => {
+        assert.strictEqual(app.people.length, 3);
+
+        const randomPerson = app.getRandomPerson();
+        assert.ok(app.people.includes(randomPerson));
+    });
+
+});
+
+test('Application - selectNextPerson',async (t) => {
+
+    await createApplication().then(app => {
+
+        assert.strictEqual(app.people.length, 3);
+
+        randomPerson = app.selectNextPerson();
+        assert.ok(app.people.includes(randomPerson));
+        assert.ok(app.selected.includes(randomPerson));
+        assert.strictEqual(app.selected.length, 1);
+
+        randomPerson = app.selectNextPerson();
+        assert.ok(app.people.includes(randomPerson));
+        assert.ok(app.selected.includes(randomPerson));
+        assert.strictEqual(app.selected.length, 2);
+
+        t.mock.method(app, 'getRandomPerson', () => randomPerson, { times: 1 });
+
+        randomPerson = app.selectNextPerson();
+        assert.ok(app.people.includes(randomPerson));
+        assert.ok(app.selected.includes(randomPerson));
+        assert.strictEqual(app.selected.length, 3);
+
+        nullPerson = app.selectNextPerson();
+        assert.strictEqual(nullPerson, null);
+        assert.strictEqual(app.selected.length, 3);
+
+    });
+
+
+});
+
+test('Application - notifySelected', async (t) => {
+    await createApplication().then(app => {
+
+        assert.strictEqual(app.people.length, 3);
+        t.mock.method(app, 'getRandomPerson', () => app.people[0]);
+
+        app.selectNextPerson();
+        t.mock.method(app.mailSystem, 'write', (name) => 'Congrats, ' + name + '!');
+        t.mock.method(app.mailSystem, 'send', (name, context) => {
+            assert.strictEqual(context, 'Congrats, ' + name + '!');
+            return true
+        });
+
+        app.notifySelected();
+    });
+
+
+});
+
+test('MailSystem - write', () => {
+    const mailSystem = new MailSystem();
+    const context = mailSystem.write('Alice');
+
+    assert.strictEqual(context, 'Congrats, Alice!');
+});
+
+test('MailSystem - send', (t) => {
+    const mailSystem = new MailSystem();
+
+    t.mock.method(Math, 'random', () => 1.0);
+
+    const result_true = mailSystem.send('Alice', 'Congratulations!');
+
+    assert.strictEqual(result_true, true);
+
+    t.mock.method(Math, 'random', () => 0.0);
+
+    const result_false = mailSystem.send('Alice', 'Congratulations!');
+
+    assert.strictEqual(result_false, false);
+
+});
+