public async Task Customers_are_correctly_formatted_in_outputfile() { var subject = new TestSubject(DefaultSize); await subject.WriteCustomers(new[] { new Customer(1, "Vladimir Makayev", 10.5, 99.4), new Customer(2, "John Doe", 10, 9) }); Assert.Equal(LineUtility.CombineWithLineBreak("1 Vladimir Makayev", "2 John Doe"), subject.GetContents()); }