title: How to use git bisect: Using unit tests for determining the errorneous commit?
body: <p>I'm new to git and just discovered "git bisect". How is it generally used when you can check for the error using a newly written unit test (that wasn't there beforehand)?</p>
  
  <p>Say we have a repository containing unit tests, but - as so often - they weren't complete. In some version we discover that a feature isn't working, but we know it was in some version before. Unfortunately that feature wasn't checked by a unit test. What I'd like to do now is:</p>
  
  <ol>
  <li>Write the test case (that fails at first of course)</li>
  <li>Look for the commit introducing the error using git bisect using this test case</li>
  <li>Correcting the error and committing the fix (and the test case)</li>
  </ol>
  
  <p>This use case has one problem. As git bisect checks out old versions, the just inserted test case won't be there, so I can't use it to check for the error. I can try to not commit the test, but to keep the it as local change. But imagining that the tests file was changed in some version inbetween, I'm likely to run into merge conflicts.</p>
  
  <p>So what to do? How is git bisect generally used?</p>