public void WhenCreatingRelativeByteReference_ByteBeneathZero_ReturnCorrectFile() { // Setup test objects LogViewModel testLogViewModel = new LogViewModel(); List <Tuple <string, long> > testLogFileLocations = new List <Tuple <string, long> > { new Tuple <string, long>("log1", 100), new Tuple <string, long>("log2", 220), new Tuple <string, long>("log3", 440), new Tuple <string, long>("log4", 660), new Tuple <string, long>("log5", 880) }; testLogViewModel.CreateLogFiles(testLogFileLocations); long byteWithinFile = -455; string logFileName = "log3"; // Perform test long relativeByteReference = testLogViewModel.CreateRelativeByteReference(byteWithinFile, logFileName); // Check test result long expectedByteReference = 320; Assert.AreEqual(expectedByteReference, relativeByteReference); }