1.2.0

Author: xxczaki

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "cashify",
-	"version": "1.1.3",
+	"version": "1.2.0",
 	"description": "Lightweight currency conversion library, successor of money.js",
 	"main": "dist/index.js",
 	"module": "dist/index.esm.js",
@@ -51,7 +51,7 @@
 		"@akepinski/tsconfig": "0.0.2",
 		"@typescript-eslint/eslint-plugin": "^1.13.0",
 		"@typescript-eslint/parser": "^1.13.0",
-		"ava": "^2.2.0",
+		"ava": "^2.3.0",
 		"browser-env": "^3.2.6",
 		"coveralls": "^3.0.6",
 		"cpy-cli": "^2.0.0",

readme.md

@@ -4,7 +4,7 @@
 
 [![Build Status](https://travis-ci.org/xxczaki/cashify.svg?branch=master)](https://travis-ci.org/xxczaki/cashify) [![Coverage Status](https://coveralls.io/repos/github/xxczaki/cashify/badge.svg?branch=master)](https://coveralls.io/github/xxczaki/cashify?branch=master) [![XO code style](https://img.shields.io/badge/code_style-XO-5ed9c7.svg)](https://github.com/xojs/xo) [![install size](https://packagephobia.now.sh/badge?p=cashify)](https://packagephobia.now.sh/result?p=cashify)
 
-This package was created, because the popular [money.js]() library is:
+This package was created, because the popular [money.js](http://openexchangerates.github.io/money.js/) library is:
 * not maintained (last commit was ~5 years ago)
 * has over 20 issues open
 * does not support TypeScript

src/index.ts

@@ -7,25 +7,31 @@ interface Options {
 	rates: object;
 }
 
+// Small helper for TypeScript
+function hasKey<T>(obj: T, key: string | number | symbol): key is keyof T {
+	return key in obj;
+}
+
 const getRate = ({base, rates, from, to}: Options): number => {
 	// If `from` equals `base`, return the basic exchange rate for the `to` currency
-	if (from === base) {
-		// @ts-ignore
+	if (from === base && hasKey(rates, to)) {
 		return rates[to];
 	}
 
 	// If `to` equals `base`, return the basic inverse rate of the `from` currency
-	if (to === base) {
-		// @ts-ignore
+	if (to === base && hasKey(rates, from)) {
 		return 1 / rates[from];
 	}
 
 	/**
 		Otherwise, return the `to` rate multipled by the inverse of the `from` rate to get the
 		relative exchange rate between the two currencies
-		*/
-	// @ts-ignore
-	return rates[to] * (1 / rates[from]);
+	*/
+	if (hasKey(rates, from) && hasKey(rates, to)) {
+		return rates[to] * (1 / rates[from]);
+	}
+
+	throw new Error('`rates` object does not contain either `from` or `to` currency!');
 };
 
 class Cashify {
@@ -44,7 +50,7 @@ class Cashify {
 	}
 
 	/**
-	* @param {number} amount Amount of money you want to convert (in decimal, e.g., $1 = 1.00)
+	* @param {number} amount Amount of money you want to convert
 	* @param {object} options Conversion options
 	* @param {string} options.from Currency from which you want to convert
 	* @param {string} options.to Currency to which you want to convert
@@ -63,7 +69,7 @@ class Cashify {
 }
 
 /**
-* @param {number} amount Amount of money you want to convert (in decimal, e.g., $1 = 1.00)
+* @param {number} amount Amount of money you want to convert
 * @param {object} options Conversion options
 * @param {string} options.from Currency from which you want to convert
 * @param {string} options.to Currency to which you want to convert

test.ts

@@ -0,0 +1,51 @@
+import test from 'ava';
+import {Cashify} from '../dist';
+
+const rates = {
+	GBP: 0.92,
+	EUR: 1.00,
+	USD: 1.12
+};
+
+const cashify = new Cashify({base: 'EUR', rates});
+
+test('basic conversion', t => {
+	t.is(cashify.convert(12, {from: 'USD', to: 'GBP'}), 9.857142857142856);
+});
+
+test('`from` equals `base`', t => {
+	t.is(cashify.convert(10, {from: 'EUR', to: 'GBP'}), 9.2);
+});
+
+test('`to` equals `base`', t => {
+	t.is(cashify.convert(10, {from: 'GBP', to: 'EUR'}), 10.869565217391303);
+});
+
+test('`from` equals `to`', t => {
+	t.is(cashify.convert(10, {from: 'USD', to: 'USD'}), 10);
+});
+
+test('`from` equals `to`, but `base` is different', t => {
+	const cashify = new Cashify({base: 'USD', rates});
+
+	t.is(cashify.convert(10, {from: 'EUR', to: 'EUR'}), 10);
+});
+
+test('`rates` without `base` currency', t => {
+	const rates = {
+		GBP: 0.92,
+		USD: 1.12
+	};
+
+	const cashify = new Cashify({base: 'EUR', rates});
+
+	t.is(cashify.convert(10, {from: 'EUR', to: 'GBP'}), 9.2);
+});
+
+test('`rates` object does not contain either `from` or `to` currency', t => {
+	const error = t.throws(() => {
+		cashify.convert(10, {from: 'CHF', to: 'EUR'});
+	}, Error);
+
+	t.is(error.message, '`rates` object does not contain either `from` or `to` currency!');
+});

test/constructor.ts

@@ -0,0 +1,45 @@
+import test from 'ava';
+import {convert} from '../dist';
+
+const rates = {
+	GBP: 0.92,
+	EUR: 1.00,
+	USD: 1.12
+};
+
+test('basic conversion', t => {
+	t.is(convert(12, {from: 'USD', to: 'GBP', base: 'EUR', rates}), 9.857142857142856);
+});
+
+test('`from` equals `base`', t => {
+	t.is(convert(10, {from: 'EUR', to: 'GBP', base: 'EUR', rates}), 9.2);
+});
+
+test('`to` equals `base`', t => {
+	t.is(convert(10, {from: 'GBP', to: 'EUR', base: 'EUR', rates}), 10.869565217391303);
+});
+
+test('`from` equals `to`', t => {
+	t.is(convert(10, {from: 'USD', to: 'USD', base: 'EUR', rates}), 10);
+});
+
+test('`from` equals `to`, but `base` is different', t => {
+	t.is(convert(10, {from: 'EUR', to: 'EUR', base: 'USD', rates}), 10);
+});
+
+test('`rates` without `base` currency', t => {
+	const rates = {
+		GBP: 0.92,
+		USD: 1.12
+	};
+
+	t.is(convert(10, {from: 'EUR', to: 'GBP', base: 'EUR', rates}), 9.2);
+});
+
+test('`rates` object does not contain either `from` or `to` currency', t => {
+	const error = t.throws(() => {
+		convert(10, {from: 'CHF', to: 'EUR', base: 'EUR', rates});
+	}, Error);
+
+	t.is(error.message, '`rates` object does not contain either `from` or `to` currency!');
+});