public void Correctly_Constructs_Write_File_Stream() { deleteTestFile(); IFileStreamFactory fileStreamFactory = new FileStreamFactory(); using (Stream stream = fileStreamFactory.ConstructWriteFileStream("test.txt")) { FileStream fileStream = (FileStream)stream; fileStream.Write(new byte[] { 7, 9, 11 }, 0, 3); } using (Stream stream = fileStreamFactory.ConstructReadFileStream("test.txt")) { byte[] fileContents = new byte[3]; Assert.That(stream.Read(fileContents, 0, 3), Is.EqualTo(3)); Assert.That(fileContents, Is.EqualTo(new byte[] { 7, 9, 11 })); } }