Updated the test system

test/merge.test.js

@@ -0,0 +1,22 @@
+const expect = require('expect');
+const {merge} = require('./_30s.js');
+
+test('merge is a Function', () => {
+  expect(merge).toBeInstanceOf(Function);
+});
+const object = {
+  a: [{ x: 2 }, { y: 4 }],
+  b: 1
+};
+const other = {
+  a: { z: 3 },
+  b: [2, 3],
+  c: 'foo'
+};
+test('Merges two objects', () => {
+  expect(merge(object, other)).toEqual({
+    a: [{ x: 2 }, { y: 4 }, { z: 3 }],
+    b: [1, 2, 3],
+    c: 'foo'
+  });
+});