>I've written entire sites on my own that happily run today.
This is probably the key issue. You're either working by yourself or you are on small enough team projects that it's easy to recognize when you are breaking things with a change.
Tests are about rapidly detecting regressions in a programmatic way. It should not require manually testing every time you want to make a small change to the code base and if you depend on reviewers seeing that a change will break something, you are in for a world of hurt on any large project.
Every large project I've been on that has skipped tests has ended up turning into a shitshow where master is broken for days at a time and you can't even tell the cause without hours of manual testing with bisection.
> if you depend on reviewers seeing that a change will break something, you are in for a world of hurt on any large project.
I don’t agree with this at all. Here’s a counter example: Linux.
I think the real problem here is that people don’t take review seriously and/or just don’t care about the project. We build these complicated, expensive systems that do all the thinking for us, not because it’s better, but because we simply don’t care.
Having tests is better than letting sloppy developers run amok. In my experience though tests aren’t really needed on projects with a maintainer that actually gives a damn.
Bad example because a massive chunk of linux is independent systems that have no overlap at all. The netlink code has jack-shit to do with a graphics driver from intel, etc.
Within subsystems regressions sneak in all of the time that don't directly cause compile-time failures.
This is probably the key issue. You're either working by yourself or you are on small enough team projects that it's easy to recognize when you are breaking things with a change.
Tests are about rapidly detecting regressions in a programmatic way. It should not require manually testing every time you want to make a small change to the code base and if you depend on reviewers seeing that a change will break something, you are in for a world of hurt on any large project.
Every large project I've been on that has skipped tests has ended up turning into a shitshow where master is broken for days at a time and you can't even tell the cause without hours of manual testing with bisection.