Improving the Customer Acceptance Test

However, while working through this, we found a bit of a difficulty. Each customer test is in a file. The files are looped over in the CustomerTest.cs class. Each test consists of executing some commands and then doing a *output command, which compares the current contents of the model with the expected value provided. The comparison was being done with a simple Assert, like this:

 private void CompareOutput(StringReader reader, String message) { 
 String expected = ExpectedOutput(reader); 
 String result = model.TestText; 
 AssertEquals(message, expected, model.TestText); 
 } 

NUnit isn t much help here. The test shows up as a failure in CustomerTest.cs and doesn t really show what happened clearly. You can sort of scroll through the output in NUnit s little window, but it s not very clear. So we improved the CustomerTest CompareOutput method:

 private void CompareOutput(StringReader reader, String message) { 
 String expected = ExpectedOutput(reader); 
 String result = model.TestText; 
  if (expected != result) {  
  Console.WriteLine(message);  
  Console.WriteLine("*Expected");  
  Console.WriteLine(expected);  
  Console.WriteLine("*Result");  
  Console.WriteLine(result);  
   } 
 AssertEquals(message, expected, model.TestText); 
 } 

Now, when a test fails, NUnit s StandardOut window looks like this, showing us just what happened: