test: lab2

lab2/main_test.js

@@ -1,6 +1,122 @@
 const test = require('node:test');
 const assert = require('assert');
-const { Application, MailSystem } = require('./main');
 
-// TODO: write your tests here
-// Remember to use Stub, Mock, and Spy when necessary
+// https://gist.github.com/sscovil/6502c72de3e24232f66b5bf86de04680
+/**
+ * Utility that waits for @predicate function to return truthy, testing at @interval until @timeout is reached.
+ *
+ * Example: await until(() => spy.called);
+ *
+ * @param {Function} predicate
+ * @param {Number} interval
+ * @param {Number} timeout
+ *
+ * @return {Promise}
+ */
+async function until(predicate, interval = 500, timeout = 30 * 1000) {
+    const start = Date.now();
+
+    let done = false;
+
+    do {
+        if (predicate()) {
+            done = true;
+        } else if (Date.now() > (start + timeout)) {
+            throw new Error(`Timed out waiting for predicate to return true after ${timeout}ms.`);
+        }
+
+        await new Promise((resolve) => setTimeout(resolve, interval));
+    } while (done !== true);
+}
+
+function mockFs(t) {
+    const fs = require('fs')
+    let mockName = ''
+    // HACK: make it usable for util.promisify
+    t.mock.method(fs, 'readFile', (_0, _1, cb) => {
+        cb(undefined, mockName);
+    });
+
+    return (name) => { mockName = name };
+}
+
+test('until', async t => {
+    let ok = false;
+    setTimeout(() => ok = true, 666);
+
+    assert.rejects(until(() => ok, 5, 20), { name: 'Error' })
+});
+
+test('Application', async t => {
+    const setMockName = mockFs(t);
+    const { Application } = require('./main');
+
+    await t.test('parse names', async () => {
+        const app = new Application();
+        setMockName('name0\nname1');
+
+        const [people, selected] = await app.getNames();
+        assert.deepStrictEqual(['name0', 'name1'], people)
+        assert.deepStrictEqual([], selected)
+    });
+
+    await t.test('parse names with cr / space', async () => {
+        const app = new Application();
+        setMockName('name0\r\nname 1');
+
+        const [people, selected] = await app.getNames();
+        assert.deepStrictEqual(['name0\r', 'name 1'], people)
+        assert.deepStrictEqual([], selected)
+    });
+
+    await t.test('selected person should populated in `selected` array', async () => {
+        setMockName(['name0', 'name1', 'name2'].join('\n'));
+        const app = new Application();
+        let nextPersonIndex = 0;
+        t.mock.method(app, 'getRandomPerson', function () {
+            return this.people[nextPersonIndex];
+        });
+        await until(() => app.people.length != 0, 100, 1000);
+
+        assert.strictEqual('name0', app.selectNextPerson());
+        nextPersonIndex++;
+        assert.strictEqual('name1', app.selectNextPerson());
+        nextPersonIndex++;
+        assert.strictEqual('name2', app.selectNextPerson());
+
+        assert.strictEqual(null, app.selectNextPerson());
+        assert.deepStrictEqual(['name0', 'name1', 'name2'], app.selected);
+    });
+
+    await t.test('selectNextPerson will dedup', async () => {
+        const people = ['name0', 'name1', 'name2'];
+        setMockName(people.join('\n'));
+        const app = new Application();
+        let nextPersonIndex = 0;
+        t.mock.method(app, 'getRandomPerson', function () {
+            const ret = this.people[nextPersonIndex];
+            nextPersonIndex = (nextPersonIndex + 1) % people.length;
+            return ret;
+        });
+        await until(() => app.people.length != 0, 100, 1000);
+
+        assert.strictEqual('name0', app.selectNextPerson());
+        nextPersonIndex = 0;
+        assert.strictEqual('name1', app.selectNextPerson());
+    });
+
+    await t.test('notifySelected', async () => {
+        setMockName(['name0', 'name1', 'name2'].join('\n'));
+        let randomResult = 0;
+        t.mock.method(Math, 'random', () => randomResult);
+        const app = new Application();
+
+        await until(() => app.people.length != 0, 100, 1000);
+
+        app.selectNextPerson();
+        app.notifySelected();
+
+        randomResult = 1;
+        app.notifySelected();
+    });
+});