testing mailsystem and app with mock

lab2/main_test.js

@@ -1,6 +1,134 @@
 const test = require('node:test');
 const assert = require('assert');
+const fs = require('fs');
+const util = require('util');
+const writeFile = util.promisify(fs.writeFile);
 const { Application, MailSystem } = require('./main');
 
 // TODO: write your tests here
-// Remember to use Stub, Mock, and Spy when necessary
+// Remember to use Stub, Mock, and Spy when necessary
+
+test("Test MailSystem's write", () => {
+    const ms = new MailSystem();
+    const context = ms.write("Jerry");
+    assert.strictEqual(context, "Congrats, Jerry!");
+});
+
+test("Test MailSystem's send", () => {
+    const ms = new MailSystem();
+    Math.random = () => 0.4;
+    let context = ms.send("Jerry", "Test Message");
+    assert.strictEqual(context, false);
+
+    Math.random = () => 0.6;
+    context = ms.send("Jerry", "Test Message");
+    assert.strictEqual(context, true);
+});
+
+test("Test Application's getNames", async() => {
+    const app = new Application();
+
+    const fn_ = "name_list.txt";
+    const data_ = "JJ\nEE\nRR\nYY";
+    await writeFile(fn_, data_, "utf-8");
+
+    let ctx = new Array([],[]);
+    ctx = await app.getNames();
+    assert.deepStrictEqual(ctx[0], ["JJ", "EE", "RR", "YY"]);
+    assert.deepStrictEqual(ctx[1], []);
+    fs.unlinkSync(fn_);
+});
+
+test("Test Application's getRandomPerson", async() => {
+    const app = new Application();
+
+    const fn_ = "name_list.txt";
+    const data_ = "JJ\nEE\nRR\nYY";
+    await writeFile(fn_, data_, "utf-8");
+
+    let ctx = new Array([],[]);
+    ctx = await app.getNames();
+    assert.deepStrictEqual(ctx[0], ["JJ", "EE", "RR", "YY"]);
+    assert.deepStrictEqual(ctx[1], []);
+
+    Math.random = () => 0.3;
+    let rdmPeople = app.getRandomPerson();
+    assert.strictEqual(rdmPeople, "EE");
+
+    Math.random = () => 0.99;
+    rdmPeople = app.getRandomPerson();
+    assert.strictEqual(rdmPeople, "YY");
+    fs.unlinkSync(fn_);
+});
+
+test("Test Application's selectNextPerson", async() => {
+    const app = new Application();
+
+    const fn_ = "name_list.txt";
+    const data_ = "JJ\nEE";
+    await writeFile(fn_, data_, "utf-8");
+
+    let ctx = new Array([],[]);
+    ctx = await app.getNames();
+    assert.deepStrictEqual(ctx[0], ["JJ", "EE"]);
+    assert.deepStrictEqual(ctx[1], []);
+
+    app.getRandomPerson = () => "JJ";
+    let person = app.selectNextPerson();
+    assert.strictEqual(person, "JJ");
+    assert.deepStrictEqual(app.selected, ["JJ"]);
+
+    app.getRandomPerson = () => "EE";
+    person = app.selectNextPerson();
+    assert.strictEqual(person, "EE");
+    assert.deepStrictEqual(app.selected, ["JJ", "EE"]);
+
+    person = app.selectNextPerson();
+    assert.strictEqual(person, null);
+    assert.deepStrictEqual(app.selected, ["JJ", "EE"]);
+
+    fs.unlinkSync(fn_);
+});
+
+test("Test Application's notifySelected", async() => {
+    const app = new Application();
+
+    const fn_ = "name_list.txt";
+    const data_ = "JJ\nEE";
+    await writeFile(fn_, data_, "utf-8");
+
+    let ctx = new Array([],[]);
+    ctx = await app.getNames();
+    assert.deepStrictEqual(ctx[0], ["JJ", "EE"]);
+    assert.deepStrictEqual(ctx[1], []);
+
+    app.getRandomPerson = () => "JJ";
+    let person = app.selectNextPerson();
+    assert.strictEqual(person, "JJ");
+    assert.deepStrictEqual(app.selected, ["JJ"]);
+
+    app.getRandomPerson = () => "EE";
+    person = app.selectNextPerson();
+    assert.strictEqual(person, "EE");
+    assert.deepStrictEqual(app.selected, ["JJ", "EE"]);
+
+    test.mock.method(app.mailSystem, 'write', (name) => "Congrats, "+name+"!");
+    test.mock.method(app.mailSystem, 'send', () => true);
+
+    app.notifySelected();
+
+    assert.strictEqual(app.mailSystem.write.mock.calls.length, 2);
+    assert.strictEqual(app.mailSystem.send.mock.calls.length, 2);
+
+    let call = app.mailSystem.write.mock.calls[0];
+    assert.deepStrictEqual(call.arguments, ["JJ"]);
+    assert.deepStrictEqual(call.result, "Congrats, JJ!");
+    assert.deepStrictEqual(call.error, undefined);
+
+    call = app.mailSystem.write.mock.calls[1];
+    assert.deepStrictEqual(call.arguments, ["EE"]);
+    assert.deepStrictEqual(call.result, "Congrats, EE!");
+    assert.deepStrictEqual(call.error, undefined);
+
+    fs.unlinkSync(fn_);
+});