Few days ago I learned a very simple, yet powerful trick which saved me some time. To make long story short, it happened on a test environment shared between few projects.

I deployed a new version of one application there, and after some time received emails with errors. Uh-oh, apparently I have broken something! Hmm… but what really happened? The stacktrace hasn’t really enlightened me in any way… Hmm…. But you know what? The entity that was printed out in the exception message looked like this:
User{email='john.kowalski.somerandomstuff@whatever.com}

And it happened that John Kowalski was my colleague working on a different team (but using the same test environment). To solve the mystery of “why-oh-why-it-does-not-work-all-tests-are-green-for-gods-sake” all I had to do was to have a short chat with him. It appeared that he was running some IT-tests which were using some incomplete data (at least from my point of view), well, it doesn’t really matter. The thing is, that thanks to him signing his work, I was able to solve my problem pretty fast.

So don’t be shy about your IT/E2E test. Sign them, and maybe someone will be thankful for this.

And BTW if you would like to learn more about writing high-quality tests then check my Bad Tests, Good Tests book.