cashAmount.js

class CashAmount {
	constructor(double) {
		this.amount = double;
	}

	totalAsPennies() {
		return Math.floor(this.amount*100);
	}

	addDoubleAmount(double) {
		this.amount = Math.floor(this.amount + double);
	}

	quantityOfEachDenomination() {
		const denominations = ['hundreds', 'fifties', 'twenties', 'tens', 'fives', 'ones', 'quarters', 'dimes', 'nickels', 'pennies'];
		const quantities = [100, 50, 20, 10, 5, 1, .25, .1, .5, .01];
		let wallet = {};
		let remaining = this.amount;
		for (let i = 0; i<10; i++) {
			wallet[denominations[i]] = 0;
			while (remaining - quantities[i] > 0) {
				remaining -= quantities[i];
				wallet[denominations[i]] += 1;
			}
		}
		return wallet;
	}

	toDouble() {
		return this.amount;
	}

	toDoubleString() {
		return this.amount.toString();
	}
}

cashTestSuite.js

class TestSuite {

	testTotalInPennies() {
		const cash = new CashAmount(10.50);
		if (cash.totalInPennies() !== 1050) {
			console.log('Fail in totalInPennies');
			return false;
		}
	}

	testAddDoubleAmount() {
		const cash = new CashAmount(10.50);
		cash.addDoubleAmount(29.33);
		if (cash.totalAsPennies() !== 3983) {
			console.log('Fail in add double');
			return false;
		}
	}

	testQuanitityOfEachDenomination() {
		const cash = new CashAmount(967.93);
		const obj =
		{
		  'hundreds': 9,
		  'fifties': 1,
		  'twenties': 0,
		  'tens': 1,
		  'fives': 1,
		  'ones': 2,
		  'quarters': 3,
		  'dimes': 1,
		  'nickels': 1,
		  'pennies': 3
		};
		const wallet = cash.quantityOfEachDenomination();
		for (let denom in wallet) {
			if (wallet[denom] !== obj[denom]) {
				console.log('fail in denominaiton, denom = ', denom);
				return false;
			}
		}
	}

	testToDouble() {
		const cash = new CashAmount(10.50);
		cash.addDoubleAmount(29.33);
		if (cash.toDouble() !== 39.83) {
			console.log('fail in to double');
			return false;
		}
	}

	testToDoubleString() {
		const cash = new CashAmount(10.50);
		cash.addDoubleAmount(29.33);
		if (cash.toDoubleString() !== '39.83') {
			console.log('fail ni to string');
			return false;
		}
	}

	test() {
		this.testTotalInPennies();
		this.testAddDoubleAmount();
		this.testQuanitityOfEachDenomination();
		this.testToDouble();
		this.testToDoubleString();
	}

		


}