Add check target and provide pre-commit hook for 'make check'

[mattkretz]

I tend to forget running check-source.sh before pushing. This might help.

[tkoeppe]

What does this change do?

[mattkretz]

If no pre-commit script exists, it installs one that runs make check in the source directory before every commit. That way one can't commit unless check-source passes.
Obviously, that's opt-in via calling this script first.

[tkoeppe]

You mean even locally? That seems a bit draconian, doesn't it? What if I just want to commit some random noise locally?

[mattkretz]

I at least don't want to commit noise that would obviously fail CI.
But yes, it might not be a feature for everybody. I could change the setup script to ask whether it should install the hook?

[tkoeppe]

I, on the other hand, as a major user of this repository, would like to commit whatever I like under whatever conditions I like...

Could you just install this script locally in your own checkout?

[tkoeppe]

How is it an opt-in given...

If no pre-commit script exists, it installs one that runs make check in the source directory before every commit.

That sounded like we'd always install the hook? Do you mean "auto opt-in"?

[mattkretz]

You have to run the tools/gitconfig.sh script manually to install the hook. If you then dislike the hook you do rm .git/hooks/pre-commit. But like I said, I can also make the script ask explicitly, because it should be recommended to run the script.

[mattkretz]

I just pushed an improved script that asks for confirmation.

[mattkretz]

Also, even with the hook installed, git commit --no-verify allows to commit failing noise :)

[tkoeppe]

OK, I see, I didn't realize that this is just an optional tool. Seems fine.

[jensmaurer]

tools/gitconfig.sh is a totally optional "whoever wants to use it" thing, and installing the hook seems totally in line with the exiting other contents.