<title>Web Sprint 3 Challenge</title>
<style>
* {
font-family: 'Times New Roman', Times, serif
}
.widget {
padding: 0 0 0.5rem 0.65rem;
margin-bottom: 0.5rem;
border: 1px solid black;
border-radius: 0.5rem;
}
.widget p {
font-style: italic;
}
❗ See the last script tag for instructions on completing your Challenge
This widget uses the EBook class
<textarea placeholder="Write your book"></textarea>
Turn Page
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js"></script>
<script id="challenge">
// In CHALLENGES 1-4 you will write JavaScript classes
// ❗ Do not rename the classes provided
// ❗ Do not alter the position of the script tags
// ❗ Debug properly using the Console
// 👉 CHALLENGE 1 - Integers
class Integers {
constructor(...args) {
this.ints = [...args];
}
getAll() {
return this.ints;
}
getEvens() {
return this.ints.filter(num => num % 2 === 0);
}
getNegatives() {
return this.ints.filter(num => num < 0);
}
getAllSquared() {
return this.ints.map(num => num * num);
}
pop() {
return this.ints.pop();
}
push(num) {
this.ints.push(num);
return this.ints;
}
getEveryNth(n) {
return this.ints.filter((_, index) => index % n === 0);
}
getAllReversed() {
return this.ints.slice().reverse();
}
}
// 👉 CHALLENGE 2 - NerfGun
class NerfGun {
constructor(totalProjectiles) {
this.maxCapacity = totalProjectiles;
this.currentCapacity = totalProjectiles;
this.safetyOn = true;
}
shoot() {
if (this.currentCapacity > 0 && !this.safetyOn) {
this.currentCapacity--;
return "Bang!";
} else {
return "Click!";
}
}
reload(number) {
if (typeof number !== "number" || number <= 0) {
return "Error reloading!";
} else {
this.currentCapacity = Math.min(this.maxCapacity, this.currentCapacity + number);
return `${this.currentCapacity} projectiles left!`;
}
}
toggleSafety() {
this.safetyOn = !this.safetyOn;
return this.safetyOn ? "Safety enabled!" : "Safety disabled!";
}
}
// 👉 CHALLENGE 3 - EBook
class EBook {
constructor(text, pageSize) {
this.text = text;
this.pageSize = pageSize;
this.currentPage = 0;
}
next() {
const nextPage = this.text.slice(this.currentPage, this.currentPage + this.pageSize);
this.currentPage += this.pageSize;
return nextPage.length > 0 ? nextPage : null;
}
}
// 👉 CHALLENGE 4 - AntFarm
class AntFarm {
constructor(...ants) {
this.ants = ants.map(name => ({ name, health: 100 }));
}
work() {
if (this.ants.length === 0) {
return "No ants here. Did you work them to death?";
}
this.ants.forEach(ant => {
ant.health -= 20;
if (ant.health <= 0) {
this.ants.splice(this.ants.indexOf(ant), 1);
}
});
return `${this.ants.length} ants starting work!`;
}
feed(name) {
const ant = this.ants.find(ant => ant.name === name);
if (ant) {
ant.health += 15;
return "Yum!";
} else {
return `${name} not found!`;
}
}
}
// 🧪 TESTS, do not make any changes below this line ===================
// 🧪 TESTS, do not make any changes below this line ===================
// 🧪 TESTS, do not make any changes below this line ===================
globalThis.challengeVersion = 1
globalThis.Integers = Integers
globalThis.NerfGun = NerfGun
globalThis.EBook = EBook
globalThis.AntFarm = AntFarm
try {
testClass('CHALLENGE 1 - class Integers', [
function () {
let actual, description = 'getAll returns all the ints'
let expected = [1, 2, 3, 4]
try {
const ints = new Integers(1, 2, 3, 4)
actual = ints.getAll()
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'getEvens returns the even ints'
let expected = [0, 2, 4]
try {
const ints = new Integers(0, 2, 3, 5, 4)
actual = ints.getEvens()
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'getNegatives returns the negative ints'
let expected = [-3, -5]
try {
const ints = new Integers(-3, 5, -5, 0)
actual = ints.getNegatives()
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'getAllSquared returns the ints squared'
let expected = [4, 1, 0, 36, 25]
try {
const ints = new Integers(2, 1, 0, 6, 5)
actual = ints.getAllSquared()
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'pop removes the last int and returns it'
let expected = [3, [1, 2]]
try {
const ints = new Integers(1, 2, 3)
actual = []
actual.push(ints.pop())
actual.push(ints.ints)
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'push adds an integer into ints and returns the updated ints'
let expected = [[1, 2, 3, 4], [1, 2, 3, 4]]
try {
const ints = new Integers(1, 2, 3)
actual = []
actual.push(ints.push(4))
actual.push(ints.ints)
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'getEveryNth returns ints at every nth index'
let expected = [[1, 3, 5], [1, 4]]
try {
const ints = new Integers(1, 2, 3, 4, 5, 6)
actual = []
actual.push(ints.getEveryNth(2))
actual.push(ints.getEveryNth(3))
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'getAllReversed returns the ints in reverse order'
let expected = [[6, 5, 4, 3, 2, 1], [0, 1, 9, 3, 6, 9]]
try {
const ints = new Integers(1, 2, 3, 4, 5, 6)
const ints2 = new Integers(9, 6, 3, 9, 1, 0)
actual = []
actual.push(ints.getAllReversed())
actual.push(ints2.getAllReversed())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
])
testClass('CHALLENGE 2 - class NerfGun', [
function () {
let actual, description = 'A new NerfGun has its safety on'
let expected = "Click!"
try {
const nerf = new NerfGun(6)
actual = nerf.shoot()
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'A NerfGun can disable safety, shoot, re-enable safety'
let expected = ["Safety disabled!", "Bang!", "Safety enabled!", "Click!"]
try {
const nerf = new NerfGun(6)
actual = []
actual.push(nerf.toggleSafety())
actual.push(nerf.shoot())
actual.push(nerf.toggleSafety())
actual.push(nerf.shoot())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'A NerfGun can not shoot after running out of projectiles'
let expected = ["Bang!", "Bang!", "Bang!", "Click!"]
try {
const nerf = new NerfGun(3)
nerf.toggleSafety()
actual = []
actual.push(nerf.shoot()); actual.push(nerf.shoot()); actual.push(nerf.shoot()); actual.push(nerf.shoot())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'A NerfGun can be reloaded to less than capacity'
let expected = ["2 projectiles left!", "Bang!", "Bang!", "Click!"]
try {
const nerf = new NerfGun(3)
nerf.toggleSafety()
nerf.shoot()
nerf.shoot()
nerf.shoot()
actual = []
actual.push(nerf.reload(2))
actual.push(nerf.shoot()); actual.push(nerf.shoot()); actual.push(nerf.shoot())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Reloading to more than capacity only fills NerfGun to capacity'
let expected = ["3 projectiles left!", "Bang!", "Bang!", "Bang!", "Click!"]
try {
const nerf = new NerfGun(3)
nerf.toggleSafety()
nerf.shoot()
actual = []
actual.push(nerf.reload(100))
actual.push(nerf.shoot()); actual.push(nerf.shoot())
actual.push(nerf.shoot()); actual.push(nerf.shoot())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Reloading NerfGun incorrectly yields an error message'
let expected = ["Error reloading!", "Error reloading!", "Error reloading!"]
try {
const nerf = new NerfGun(6)
actual = []
actual.push(nerf.reload(0))
actual.push(nerf.reload(-1))
actual.push(nerf.reload('5'))
} catch (err) { actual = err.message }
return [description, expected, actual]
},
])
testClass('CHALLENGE 3 - class EBook', [
function () {
let actual, description = 'Ebook can turn pages'
let expected = ['abc', 'def', 'g']
try {
const book = new EBook('abcdefg', 3)
actual = []
actual.push(book.next()); actual.push(book.next()); actual.push(book.next())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Turning page yields null when there is no more text'
let expected = ['abcd', 'efgh', 'ij', null, null]
try {
const book = new EBook('abcdefghij', 4)
actual = []
actual.push(book.next()); actual.push(book.next()); actual.push(book.next())
actual.push(book.next()); actual.push(book.next())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
])
testClass('CHALLENGE 4 - class AntFarm', [
function () {
let actual, description = 'AntFarm initializes the ants correctly'
let expected = [
{ name: 'Jess', health: 100 }, { name: 'Blake', health: 100 }, { name: 'Jess', health: 100 }
]
try {
const farm = new AntFarm('Jess', 'Blake', 'Jess')
actual = farm.ants
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Working substracts 20 health points'
let expected = [
{ name: 'Jess', health: 80 }, { name: 'Blake', health: 80 }, { name: 'Jess', health: 80 }
]
try {
const farm = new AntFarm('Jess', 'Blake', 'Jess')
farm.work()
actual = farm.ants
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Overworking kills the ants'
let expected = []
try {
const farm = new AntFarm('Jess', 'Blake', 'Jess')
farm.work(); farm.work(); farm.work(); farm.work(); farm.work()
actual = farm.ants
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Working returns the correct string'
let expected = ["3 ants starting work!", "1 ants starting work!", "No ants here. Did you work them to death?"]
try {
const farm = new AntFarm('Jess', 'Blake', 'Jess')
farm.ants[0].health++
actual = []
farm.work(); farm.work(); farm.work(); farm.work()
actual.push(farm.work()); actual.push(farm.work()); actual.push(farm.work())
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Feeding increases 15 health points of lucky ant(s)'
let expected = [{ name: "Jess", "health": 115 }, { name: "Blake", health: 100 }, { name: "Jess", health: 115 }]
try {
const farm = new AntFarm('Jess', 'Blake', 'Jess')
farm.feed('Jess')
actual = farm.ants
} catch (err) { actual = err.message }
return [description, expected, actual]
},
function () {
let actual, description = 'Feeding returns the correct string'
let expected = ["Yum!", "bad name not found!", "another bad name not found!"]
try {
const farm = new AntFarm('Jess', 'Blake', 'Jess')
actual = []
actual.push(farm.feed('Blake'))
actual.push(farm.feed('bad name'))
actual.push(farm.feed('another bad name'))
} catch (err) { actual = err.message }
return [description, expected, actual]
},
])
function testClass(testTitle, tests) {
console.log(testTitle)
tests.forEach((test, idx) => {
const [, expected, actual] = test()
const [desJSON, expJSON, actJSON] = test().map(JSON.stringify)
if (_.isEqual(expected, actual)) {
console.log(`\t✅ Test ${idx + 1} ${desJSON} PASSED`)
} else {
console.log(`\t❌ Test ${idx + 1} ${desJSON} FAILED:
Expected ${expJSON}
Actual ${actJSON}`)
}
})
}
let getTextArea = () => document.querySelector('.widget textarea')
let getNumberInput = () => document.querySelector('.widget input[type=number]')
const getText = () => getTextArea().value
const getChars = () => Number(getNumberInput().value)
turnPage.disabled = true
let book
let updateBook = () => {
turnPage.disabled = (getText() && getChars() && getChars() > 0) ? false : true
book = new EBook(getText(), getChars())
}
getTextArea().oninput = updateBook
getNumberInput().oninput = updateBook
turnPage.onclick = () => {
bookPage.textContent = book.next() || 'The End'
}
} catch (err) { console.error(err.stack) }
</script>