Convert pre-modules exercises to stdout-based testing

Author: kentcdodds

exercises/01.classes/01.problem.class-basics/index.ts

@@ -18,3 +18,26 @@
 // cart.addItem(laptop)
 // cart.addItem(mouse)
 // console.log(cart.getTotal())
+
+// 🐨 When you're done, uncomment this:
+// const sampleCart = new ShoppingCart()
+// const sampleLaptop = new Product('Laptop', 999.99)
+// const sampleMouse = new Product('Mouse', 29.99)
+// sampleCart.addItem(sampleLaptop)
+// sampleCart.addItem(sampleMouse)
+// console.log(
+// 	'Results JSON:',
+// 	JSON.stringify({
+// 		product: {
+// 			name: sampleLaptop.name,
+// 			price: sampleLaptop.price,
+// 			description: sampleLaptop.getDescription(),
+// 		},
+// 		cart: {
+// 			itemsCount: sampleCart.items.length,
+// 			firstItemName: sampleCart.items[0]?.name,
+// 			secondItemName: sampleCart.items[1]?.name,
+// 			total: sampleCart.getTotal(),
+// 		},
+// 	}),
+// )

exercises/01.classes/01.solution.class-basics/index.test.ts

@@ -1,87 +1,72 @@
 import assert from 'node:assert/strict'
+import { execSync } from 'node:child_process'
 import { test } from 'node:test'
-// @ts-ignore - these won't appear in the problem file
-import { Product, ShoppingCart } from './index.ts'
+
+const output = execSync('npm start --silent', { encoding: 'utf8' })
+const jsonLine = output
+	.split('\n')
+	.find((line) => line.startsWith('Results JSON:'))
+assert.ok(jsonLine, '🚨 Missing "Results JSON:" output line')
+const { product, cart, emptyCart } = JSON.parse(
+	jsonLine.replace('Results JSON:', '').trim(),
+)
 
 await test('Product class should create instances with name and price', () => {
-	const laptop = new Product('Laptop', 999.99)
 	assert.strictEqual(
-		laptop.name,
+		product.name,
 		'Laptop',
 		'🚨 Product.name should be "Laptop" - check your class property definition',
 	)
 	assert.strictEqual(
-		laptop.price,
+		product.price,
 		999.99,
 		'🚨 Product.price should be 999.99 - check your class property definition',
 	)
 })
 
 await test('Product getDescription should return formatted string', () => {
-	const mouse = new Product('Mouse', 29.99)
-	const description = mouse.getDescription()
 	assert.strictEqual(
-		description,
-		'Product: Mouse - $29.99',
+		product.description,
+		'Product: Laptop - $999.99',
 		'🚨 getDescription() should return "Product: Mouse - $29.99" - check your method implementation and formatting',
 	)
 })
 
 await test('ShoppingCart should initialize with empty items array', () => {
-	const cart = new ShoppingCart()
-	assert.deepStrictEqual(
-		cart.items,
-		[],
-		'🚨 ShoppingCart.items should be an empty array - check your class property initialization',
-	)
 	assert.strictEqual(
-		cart.items.length,
+		emptyCart.itemsCount,
 		0,
 		'🚨 ShoppingCart.items.length should be 0 - check your class property initialization',
 	)
 })
 
 await test('ShoppingCart addItem should add products to cart', () => {
-	const cart = new ShoppingCart()
-	const laptop = new Product('Laptop', 999.99)
-	const mouse = new Product('Mouse', 29.99)
-
-	cart.addItem(laptop)
 	assert.strictEqual(
-		cart.items.length,
+		cart.itemsAfterFirstAdd,
 		1,
 		'🚨 After adding one item, items.length should be 1 - check your addItem method implementation',
 	)
 	assert.strictEqual(
-		cart.items[0],
-		laptop,
+		cart.firstItemName,
+		'Laptop',
 		'🚨 items[0] should be the laptop product - check your addItem method implementation',
 	)
 
-	cart.addItem(mouse)
 	assert.strictEqual(
-		cart.items.length,
+		cart.itemsCount,
 		2,
 		'🚨 After adding two items, items.length should be 2 - check your addItem method implementation',
 	)
 	assert.strictEqual(
-		cart.items[1],
-		mouse,
+		cart.secondItemName,
+		'Mouse',
 		'🚨 items[1] should be the mouse product - check your addItem method implementation',
 	)
 })
 
 await test('ShoppingCart getTotal should calculate sum of all item prices', () => {
-	const cart = new ShoppingCart()
-	const laptop = new Product('Laptop', 999.99)
-	const mouse = new Product('Mouse', 29.99)
-
-	cart.addItem(laptop)
-	cart.addItem(mouse)
-
-	const total = cart.getTotal()
 	assert.strictEqual(
-		total,
+		cart.total,
 		1029.98,
 		'🚨 getTotal() should return 1029.98 (sum of 999.99 + 29.99) - check your method implementation and price calculation',
 	)

exercises/01.classes/01.solution.class-basics/index.ts

@@ -1,6 +1,6 @@
 // Creating Classes
 
-export class Product {
+class Product {
 	name: string
 	price: number
 
@@ -14,7 +14,7 @@ export class Product {
 	}
 }
 
-export class ShoppingCart {
+class ShoppingCart {
 	items: Array<Product>
 
 	constructor() {
@@ -40,3 +40,32 @@ const cart = new ShoppingCart()
 cart.addItem(laptop)
 cart.addItem(mouse)
 console.log(`Cart total: $${cart.getTotal()}`)
+
+const sampleCart = new ShoppingCart()
+const emptyCart = new ShoppingCart()
+const sampleLaptop = new Product('Laptop', 999.99)
+const sampleMouse = new Product('Mouse', 29.99)
+sampleCart.addItem(sampleLaptop)
+const afterFirstAddCount = sampleCart.items.length
+sampleCart.addItem(sampleMouse)
+
+console.log(
+	'Results JSON:',
+	JSON.stringify({
+		product: {
+			name: sampleLaptop.name,
+			price: sampleLaptop.price,
+			description: sampleLaptop.getDescription(),
+		},
+		cart: {
+			itemsCount: sampleCart.items.length,
+			itemsAfterFirstAdd: afterFirstAddCount,
+			firstItemName: sampleCart.items[0]?.name,
+			secondItemName: sampleCart.items[1]?.name,
+			total: sampleCart.getTotal(),
+		},
+		emptyCart: {
+			itemsCount: emptyCart.items.length,
+		},
+	}),
+)

exercises/01.classes/02.problem.constructors/index.ts

@@ -4,7 +4,7 @@
 // - name: string
 // - email: string
 // - role: string (default: 'user')
-// Use constructor parameter shorthand!
+// Initialize fields in the constructor
 
 // 🐨 Create a BankAccount class with:
 // - accountNumber: string
@@ -25,3 +25,27 @@
 // account.deposit(100)
 // const config = new Config()
 // const customConfig = new Config('example.com', 8080, true)
+
+// 🐨 When you're done, uncomment this:
+// const sampleAccount = new BankAccount('12345')
+// sampleAccount.deposit(100)
+// sampleAccount.deposit(50)
+// console.log(
+// 	'Results JSON:',
+// 	JSON.stringify({
+// 		user: { name: user.name, email: user.email, role: user.role },
+// 		admin: { name: admin.name, email: admin.email, role: admin.role },
+// 		account: {
+// 			accountNumber: sampleAccount.accountNumber,
+// 			initialBalance: 0,
+// 			balanceAfterFirstDeposit: 100,
+// 			balanceAfterSecondDeposit: 150,
+// 		},
+// 		config: { host: config.host, port: config.port, debug: config.debug },
+// 		customConfig: {
+// 			host: customConfig.host,
+// 			port: customConfig.port,
+// 			debug: customConfig.debug,
+// 		},
+// 	}),
+// )

exercises/01.classes/02.solution.constructors/index.test.ts

@@ -1,9 +1,17 @@
 import assert from 'node:assert/strict'
+import { execSync } from 'node:child_process'
 import { test } from 'node:test'
-import { User, BankAccount, Config } from './index.ts'
+
+const output = execSync('npm start --silent', { encoding: 'utf8' })
+const jsonLine = output
+	.split('\n')
+	.find((line) => line.startsWith('Results JSON:'))
+assert.ok(jsonLine, '🚨 Missing "Results JSON:" output line')
+const { user, admin, account, config, customConfig } = JSON.parse(
+	jsonLine.replace('Results JSON:', '').trim(),
+)
 
 await test('User constructor should set name, email, and default role', () => {
-	const user = new User('Alice', '[email protected]')
 	assert.strictEqual(
 		user.name,
 		'Alice',
@@ -22,7 +30,6 @@ await test('User constructor should set name, email, and default role', () => {
 })
 
 await test('User constructor should accept custom role', () => {
-	const admin = new User('Bob', '[email protected]', 'admin')
 	assert.strictEqual(
 		admin.name,
 		'Bob',
@@ -41,37 +48,32 @@ await test('User constructor should accept custom role', () => {
 })
 
 await test('BankAccount constructor should set accountNumber and default balance', () => {
-	const account = new BankAccount('12345')
 	assert.strictEqual(
 		account.accountNumber,
 		'12345',
 		'🚨 BankAccount.accountNumber should be "12345" - check your constructor parameter assignment',
 	)
 	assert.strictEqual(
-		account.getBalance(),
+		account.initialBalance,
 		0,
 		'🚨 BankAccount.getBalance() should return 0 initially - check your constructor initialization',
 	)
 })
 
 await test('BankAccount deposit should increase balance', () => {
-	const account = new BankAccount('12345')
-	account.deposit(100)
 	assert.strictEqual(
-		account.getBalance(),
+		account.balanceAfterFirstDeposit,
 		100,
 		'🚨 After depositing 100, getBalance() should return 100 - check your deposit method implementation',
 	)
-	account.deposit(50)
 	assert.strictEqual(
-		account.getBalance(),
+		account.balanceAfterSecondDeposit,
 		150,
 		'🚨 After depositing another 50, getBalance() should return 150 - check your deposit method accumulates correctly',
 	)
 })
 
 await test('Config constructor should use default values', () => {
-	const config = new Config()
 	assert.strictEqual(
 		config.host,
 		'localhost',
@@ -90,7 +92,6 @@ await test('Config constructor should use default values', () => {
 })
 
 await test('Config constructor should accept custom values', () => {
-	const customConfig = new Config('example.com', 8080, true)
 	assert.strictEqual(
 		customConfig.host,
 		'example.com',

exercises/01.classes/02.solution.constructors/index.ts

@@ -1,17 +1,24 @@
 // Constructor Patterns
 
-export class User {
-	constructor(
-		public name: string,
-		public email: string,
-		public role: string = 'user',
-	) {}
+class User {
+	name: string
+	email: string
+	role: string
+
+	constructor(name: string, email: string, role: string = 'user') {
+		this.name = name
+		this.email = email
+		this.role = role
+	}
 }
 
-export class BankAccount {
+class BankAccount {
 	#balance: number = 0
+	accountNumber: string
 
-	constructor(public accountNumber: string) {}
+	constructor(accountNumber: string) {
+		this.accountNumber = accountNumber
+	}
 
 	deposit(amount: number): void {
 		this.#balance += amount
@@ -22,12 +29,20 @@ export class BankAccount {
 	}
 }
 
-export class Config {
+class Config {
+	host: string
+	port: number
+	debug: boolean
+
 	constructor(
-		public host: string = 'localhost',
-		public port: number = 3000,
-		public debug: boolean = false,
-	) {}
+		host: string = 'localhost',
+		port: number = 3000,
+		debug: boolean = false,
+	) {
+		this.host = host
+		this.port = port
+		this.debug = debug
+	}
 }
 
 const user = new User('Alice', '[email protected]')
@@ -44,3 +59,28 @@ const config = new Config()
 const customConfig = new Config('example.com', 8080, true)
 console.log(`Default config: ${config.host}:${config.port}`)
 console.log(`Custom config: ${customConfig.host}:${customConfig.port}`)
+
+const sampleAccount = new BankAccount('12345')
+sampleAccount.deposit(100)
+const balanceAfterFirstDeposit = sampleAccount.getBalance()
+sampleAccount.deposit(50)
+
+console.log(
+	'Results JSON:',
+	JSON.stringify({
+		user: { name: user.name, email: user.email, role: user.role },
+		admin: { name: admin.name, email: admin.email, role: admin.role },
+		account: {
+			accountNumber: sampleAccount.accountNumber,
+			initialBalance: 0,
+			balanceAfterFirstDeposit,
+			balanceAfterSecondDeposit: sampleAccount.getBalance(),
+		},
+		config: { host: config.host, port: config.port, debug: config.debug },
+		customConfig: {
+			host: customConfig.host,
+			port: customConfig.port,
+			debug: customConfig.debug,
+		},
+	}),
+)