feat: add swapElements function (#153)

* feat(*): add swapElements function

this is a completely new feature, swapElements swaps two elements at a given array at specified

indexes

*

* style(*): ESlint corrections

Corrections in code as removing semicolons, changing line breaks from CRLF to LF, adding whitespaces

Author: turisap

src/index.js

@@ -53,6 +53,7 @@ import find from './find'
 import median from './array-median'
 import timeDifference from './timeDifference'
 import isPrime from './is-prime'
+import swapElements from './swapElements'
 
 export {
   isOdd,
@@ -110,4 +111,5 @@ export {
   median,
   timeDifference,
   isPrime,
+  swapElements,
 }

src/swapElements.js

@@ -0,0 +1,20 @@
+/**
+ * Created by HP on 3/1/2018.
+ */
+export default swapElements
+
+
+/**
+ * Original source https://stackoverflow.com/questions/872310/javascript-swap-array-elements
+ *
+ * This function swaps elements at indexes 'a' and 'b' in array 'target'
+ *
+ * @param {Number} x - the first index in the array 'target'
+ * @param {Number} y - the second index in the array 'target'
+ * @param {Array} list - targeted array
+ */
+function swapElements(x, y, list) {
+  const b = list[y]
+  list[y] = list[x]
+  list[x] = b
+}

test/swapElements.test.js

@@ -0,0 +1,11 @@
+/**
+ * Created by HP on 3/1/2018.
+ */
+import test from 'ava';
+import {swapElements} from '../src';
+
+test('should swap two elements at given indexes in the targeted array', t => {
+    const target = [1,2,3];
+    swapElements(1,2,target);
+    t.deepEqual(target, [1,3,2]);
+});