public void TestMicrowaveOven_ArchiveMessageMethod()
        {
            Mock <IWriter>     writer = new Mock <IWriter>();
            Mock <IRepository> repo   = new Mock <IRepository>();

            IClient microwave = new MicrowaveOven(writer.Object, repo.Object);

            microwave.ArchiveMessageInServer(Msg);

            repo.Verify(x => x.ArchiveMessage(It.Is <string>(s => s == Msg)), Times.Once, "The given message was not stored in the repository");
        }