[nickcox]

High coverage isn't enough but, in my experience, it's a great place to start.

I've written an depressingly high quantity of code in my career that blows up literally the first time it runs. I'd much rather that happen in a unit test than in production.

Any test that exercises a given branch is better than nothing.

[lmm]

Coverage can tell you what you didn't test, but it can't tell you what you did test.

> Any test that exercises a given branch is better than nothing.

I disagree with this. If you have a test that doesn't actually test anything, you can't tell that you're not really testing that branch. No test is better than a bad test because it's easier to fix.