Test migration to jest by hand

Apparently using regular expressions is way easier.

test/permutations/permutations.js

@@ -0,0 +1,11 @@
+const permutations = arr => {
+if (arr.length <= 2) return arr.length === 2 ? [arr, [arr[1], arr[0]]] : arr;
+return arr.reduce(
+(acc, item, i) =>
+acc.concat(
+permutations([...arr.slice(0, i), ...arr.slice(i + 1)]).map(val => [item, ...val])
+),
+[]
+);
+};
+module.exports = permutations;

test/permutations/permutations.test.js

@@ -0,0 +1,10 @@
+const expect = require('expect');
+const permutations = require('./permutations.js');
+
+
+  test('permutations is a Function', () => {
+  expect(permutations).toBeInstanceOf(Function);
+});
+  t.deepEqual(permutations([1, 33, 5]), [ [ 1, 33, 5 ], [ 1, 5, 33 ], [ 33, 1, 5 ], [ 33, 5, 1 ], [ 5, 1, 33 ], [ 5, 33, 1 ] ], 'Generates all permutations of an array');
+  
+