this might be a dumb question, but what’s the “right” way to write a file into the same directory as your repo when running a script through a

pex_binary

? using

__file__

as a starting point doesn’t work since all the files are running in pants’ temp directory

Not at all dumb. Imo it's confusing, and I still get confused by it! This is relevant https://github.com/pantsbuild/pants/issues/12129 For Pants's own scripts, we simply use a relative path from the build root and it Just Works. Like

Path("dir/write_me.txt")

hmm, so something like this should work?

with open(Path("src/path/to/whatever.json"), "w") as f_:
    json.dump(data, f_)

what if i didn’t know beforehand where the output would be, or wanted to write something relative to the file where a function is being called?

Path(__file__).absolute()

unfortunately returns the file from the pantsdir and not the actual repo

yes that is right. Re dynamic, cc @bitter-ability-32190 who has been looking into this - do you know how?

the best I’ve come up with is this:

Path().joinpath("src", *__package__.split("."), "file.ext").absolute()

which works but feels weird and not at all like the right way to do things 😛 (and it also requires hardcoding in the

src/

directory)

You basically got it. We don't use source roots, so we don't worry about

src

. Admittedly not great

Hm not great indeed. I wonder how we fix this. Probably https://github.com/pantsbuild/pants/issues/12129

Actually I wonder if we could do this a different way. What if we didn't source-root-strip in the sandbox for

run

, but set the right PYTHONPATH? Ehh, probably wouldnt work right, still. Just another indirection

that is what we do -- we never "strip" w/ Python btw, I believe: https://github.com/pantsbuild/pants/blob/65a3e9967be0b3e245c41a8c87c1d51f59d3351a/src/python/pants/backend/python/goals/run_pex_binary.py#L109

Yeah, if you have a source root, I think theres no way to fall into the pit of success on this one 😕