feat(isEven): Add isEven function (#103)

* feat(isEven): Add isEven function

Add isEven function which checks if a given number is even or not

* feat(isEven): Add isEven function

Add isEven function which checks if a given number is even or not

Closed #101

Author: GeoDoo

src/index.js

@@ -1,3 +1,4 @@
+import isEven from './is-even'
 import revstring from './revstring'
 import initArray from './init-array'
 import reduce from './reduce-to-tally'
@@ -35,6 +36,7 @@ import round from './round'
 import checkPalindrome from './checkPalindrome'
 
 export {
+  isEven,
   revstring,
   initArray,
   reduce,

src/is-even.js

@@ -0,0 +1,14 @@
+export default isEven
+
+/**
+ * Original Source:
+ * https://stackoverflow.com/questions/16929958/how-to-determine-if-a-number-is-odd-or-even-in-java-script
+ *
+ * This method will check if a number is even or not.
+ *
+ * @param {Number} n - number to check
+ * @return {Boolean} - True if n is even, false if not
+ */
+function isEven(n) {
+  return n === parseFloat(n) && !(n % 2)
+}

test/is-even.test.js

@@ -0,0 +1,16 @@
+import test from 'ava'
+import {isEven} from '../src'
+
+test('checks if number is even and returns true', t => {
+  const n = 26
+  const expected = true
+  const actual = isEven(n)
+  t.deepEqual(actual, expected)
+})
+
+test('checks if number is even and returns false', t => {
+  const n = 27
+  const expected = false
+  const actual = isEven(n)
+  t.deepEqual(actual, expected)
+})