“What/who tests the tests?” This question arises at some point while learning Test-Driven Development (TDD). If every piece of production code ends up tested in the TDD process by construction, does the same apply to the code of the produced tests themselves?
It’s time to go meta.
Before we talk about how a test case could end, let’s recall its canonical structure. It is needed because we will refer to events that can happen in test’s …
Do you write your tests after corresponding production code has been written? Do you run your new test, see it pass, consider the job done and then move on onto the next task?
Here is a thought experiment for you. I hope it will illustrate a problem with this approach …
There is one thing that has bothered me about the asymmetry of relation between the production code and the test code. People often say: “Your tests test the production code, and production code ensures the tests are not broken”.
But it did not feel right. Especially after learning the principle …