ci: add whitespace check

[Alizter]

This adds a whitespace check to the CI that fails if there is trailing white space or a file does not end with a newline.

[jdchristensen]

I thought it was pretty funny that in an earlier version, whitespace.yml didn't end in a newline... 😄

[Alizter]

@jdchristensen OK sorry for the noise. I think I'm done with this sprint. The first commit adds the CI checks. The second fixes the end newlines and the third fixes the trailing white spaces. Just to be sure I will push each commit separately again.

[Alizter]

Here is the first commit, it should fail the check as there are trailing whitespaces in the library. And it does.

[Alizter]

Here is the second commit, it should fail because only the trailing white spaces have been fixed but there are still problems with the end newlines.

[Alizter]

Here is the third commit. The end newlines have now been fixed and all the checks pass.

[Alizter]

Once we merge this, I'll prepare a PR that ignores these commits from git blame so that there aren't spurious blames everywhere and our history is clean. I can't do that now as the hash might change.

[Alizter]

I got something sort-of working, but I can't get github actions to print the commit, file and location of the whitespace. I am out of energy for today, so I will take another look later.

[Alizter]

The commit hook suggestion here works fine by the way. I just noticed I still had that commit hook lying around, its just it wasn't marked as executable and that's why it didn't work.

[jdchristensen]

The commit hook suggestion here works fine by the way. I just noticed I still had that commit hook lying around, its just it wasn't marked as executable and that's why it didn't work.

Can you summarize the current situation? I'm not sure what you mean by "works fine", and I'm not sure if you are talking about something that runs locally when someone creates a commit or about something that runs in the CI.

[Alizter]

Yes, we should be able to write a script that git runs in the pre commit hook that checks if there is white space and removes it. That way changes to files that are committed automatically get their whitespace pruned.

Previously I had a script, but I didn't mark it as executable which is why I erroneously thought the precommit hooks were broken.