Chai Promise Test Pattern

            describe('when successful', () => {
                it('should return all items', () => {
                    return todo.findAll(request, response)
                        .then(() => {
                            var actual = response._getData();
                            expect(actual).to.deep.equal(testData);
                        }).catch((err) => {
                            throw err
                        });
                });

                it('should return a 200 ok', () => {

                    return todo.findAll(request, response)
                        .then(() => {
                            expect(response.statusCode).to.equal(200);
                        }).catch((err) => {
                            throw err;
                        });
                });
            });