Updated the test system

test/without.test.js

@@ -0,0 +1,43 @@
+const expect = require('expect');
+const {without} = require('./_30s.js');
+
+test('without is a Function', () => {
+  expect(without).toBeInstanceOf(Function);
+});
+test('without([2, 1, 2, 3], 1, 2) returns [3]', () => {
+  expect(without([2, 1, 2, 3], 1, 2)).toEqual([3]);
+});
+test('without([]) returns []', () => {
+  expect(without([])).toEqual([]);
+});
+test("without([3, 1, true, '3', true], '3', true) returns [3, 1]", () => {
+  expect(without([3, 1, true, '3', true], '3', true)).toEqual([3, 1]);
+});
+test("without('string'.split(''), 's', 't', 'g') returns ['r', 'i', 'n']", () => {
+  expect(without('string'.split(''), 's', 't', 'g')).toEqual(['r', 'i', 'n']);
+});
+test('without() throws an error', () => {
+  expect(() => {
+    without();
+  }).toThrow();
+});
+test('without(null) throws an error', () => {
+  expect(() => {
+    without(null);
+  }).toThrow();
+});
+test('without(undefined) throws an error', () => {
+  expect(() => {
+    without(undefined);
+  }).toThrow();
+});
+test('without(123) throws an error', () => {
+  expect(() => {
+    without(123);
+  }).toThrow();
+});
+test('without({}) throws an error', () => {
+  expect(() => {
+    without({});
+  }).toThrow();
+});