Updated the test system

test/truthCheckCollection.test.js

@@ -0,0 +1,14 @@
+const expect = require('expect');
+const {truthCheckCollection} = require('./_30s.js');
+
+test('truthCheckCollection is a Function', () => {
+  expect(truthCheckCollection).toBeInstanceOf(Function);
+});
+test('second argument is truthy on all elements of a collection', () => {
+  expect(
+    truthCheckCollection(
+      [{ user: 'Tinky-Winky', sex: 'male' }, { user: 'Dipsy', sex: 'male' }],
+      'sex'
+    )
+  ).toBeTruthy();
+});