If you're saying tests are an alternative to using a debugger, then I disagree. Tests are very useful, but they fulfill a different need to debuggers. In fact

If you're saying tests are an alternative to using a debugger, then I disagree. Tests are very useful, but they fulfill a different need to debuggers. In fact the two work well together: stepping through a failing test case with a debugger can be a very effective way to find the root cause of a problem.