Add support for buildifier style in BUILD files, or support running an auto-format binary after `pants tailor` about pants HOT 7 OPEN

I don't know if this works as any of the tailor stuff I run is pretty basic, but would something like this work for you?

I'm not entirely sure if fmt necessarily runs after tailor, but even if not, creating the new build files should tell fmt that the filesystem has changed and kick it off anyways.

backend_packages = [
    "pants.backend.build_files.fmt.buildifier",
    ...

pants tailor fmt ::

As a fallback, if that didn't work, then maybe something like pants tailor :: && pants fmt ::

https://www.pantsbuild.org/2.20/reference/subsystems/buildifier

from pants.

Yes, those work, and are a way to avoid manually running buildifier, but in exchange you manually run pants tailor. It seems reasonable that anything generated by pants should then be formatted by pants. In other words, it should be that this is something we shouldn't have to think about.

from pants.

I'll concede, I'm a bit confused as to your workflow now.

support running an auto-format binary after pants tailor

by default, pants tailor creates BUILD files that do not conform to this binary, so now users have to run pants tailor and then manually go and run buildifier.

How are you running pants tailor if not manually? And what's the incremental effort to running pants tailor fmt?

from pants.

Yes, we're running it manually. I'd prefer to just run one command, otherwise we need to mention to everyone the "proper" way to create new build files, which is not just to run pants tailor but to do other things as well. This feature request would simplify that.

from pants.

So, in pants it's pretty typical to chain goals as a single command:
pants fix fmt lint check ::

That's a very common paradigm, so pants tailor fmt :: would be a single command running 2 goals against all targets.

If you wanted to "simplify" it, you could create an alias to do that for you (https://www.pantsbuild.org/2.20/reference/subsystems/cli#alias).

[cli.alias]
ftailor = "tailor fmt"

from pants.

Thanks, I agree that's better than I had originally come up with.

I still think, though, that automatically formatting (if Pants knows how) anything Pants generates would be a completely reasonable thing to implement, and would help simplify this. Ideally, Pants should get things right without workarounds, even simple ones.

from pants.

I agree with your point that this could be better: pants is writing new data to file that it (a) knows how to reformat, and (b) knows should be reformatted. Would be a nice quality-of-life improvement to do the reformatting automatically!

It looks like this is the rule that does the editing, including reading the existing contents:

I'm not exactly sure how we'd apply the appropriate build file formatting rules likely something involving rules from https://github.com/pantsbuild/pants/blob/0d35991d0814fa4f45ce504933d143525898e653/src/python/pants/core/goals/update_build_files.py

from pants.