0.Debugging vs. Testing§

Debugging: (Localizing and) fixing a (known) bug
Testing: Recognizing that you have a specific bug
Debugging is hard! Testing is harder. You probably don’t have a lot of experience with testing.
JUnit tests are meant to help you test, and to help you not spend countless hours debugging.
Regression Testing: Include tests that verify all of your fixed bugs remain fixed as you continue to evolve your program.

Testing and Web-CAT

Anytime you submit to Web-CAT and fail a grader test that you did not expect to fail, it represents YOUR failure to properly test.
I am not your testing service. Nor is Web-CAT. We don’t share our test cases.
Real problem: How to correct a mis-understanding.

Testing vs. Anti-Testing (1)

Testing means that you ran your program, and verified that certain behavior is correct.
Anti-testing (in the context of JUnit tests) is running a unit test that gives code coverage on lines that have not been positively verified to behave correctly.
Typical anti-test: Give the program a lot of commands (gets code coverage) and ignore the results (or copy a dump of the results back into the output check in order to “pass”).

Testing vs. Anti-Testing (2)

Why Anti-testing is disastrous:
- If you have real tests, then you can expect that your bugs are in the uncovered lines. So you know where to look.
- Throw in an anti-test, and now you can’t tell which lines are demonstrated correct and which are not.