const expect = require('expect'); const functions = require('./functions.js'); test('Testing functions', () => { //For more information on all the methods supported by tape //Please go to https://github.com/substack/tape expect(typeof functions === 'function').toBeTruthy(); function Foo() { this.a = () => 1; this.b = () => 2; } Foo.prototype.c = () => 3; expect(functions(new Foo())).toEqual(['a', 'b']); expect(functions(new Foo(), true)).toEqual(['a', 'b', 'c']); });