Added test for ScrambleStrings and formatted folder structure for other folders

Sorts/test/SelectionSort.test.js

@@ -0,0 +1,22 @@
+import { selectionSort } from '../SelectionSort'
+
+describe('selectionSort', () => {
+  it('expects to return the array sorted in ascending order', () => {
+    const toSort = [5, 6, 7, 8, 1, 2, 12, 14]
+    const expected = [1, 2, 5, 6, 7, 8, 12, 14]
+
+    expect(selectionSort(toSort)).toEqual(expected)
+  })
+
+  it('expects to throw if it is not a valid array', () => {
+    expect(() => selectionSort('abc')).toThrow('Given input is not an array')
+    expect(() => selectionSort(123)).toThrow('Given input is not an array')
+    expect(() => selectionSort({})).toThrow('Given input is not an array')
+    expect(() => selectionSort(null)).toThrow('Given input is not an array')
+    expect(() => selectionSort()).toThrow('Given input is not an array')
+  })
+
+  it('expects to throw if one of the elements in the array is not a number', () => {
+    expect(() => selectionSort([1, 'x', 2])).toThrow('One of the items in your array is not a number')
+  })
+})