title: Is useless to do unit test after writing code?
body: <p>I finished an app and after that I'm trying to write unit test to cover all methods.</p>
  
  <p>The thing is that Im seeing that I'm testing my code with the knowledge of how it works.</p>
  
  <p>For me is a bit stupid because I know how the code works and I'm testing what is my code actually doing.</p>
  
  <p>My question is:</p>
  
  <p>Is this useless? Im testing what it does, not what it is supposing to do. My code works but I can improve it. Then:</p>
  
  <p>Should I complete all my tests and then try to refactor my code changing my test to "How the code should work" and making the changes to the app to pass the test?</p>
  
  <p>Thank you.</p>