Hi Pants, I have a question about

./pants tailor

. We want to use it to check whether we have all the BUILD files and targets we need, and found 2 problems: 1. it always generates a

BUILD

file at the repo root, which we actually don't want; and 2. it generates a bunch of

pex_binary

targets which we don't need either. What are the rules that make

tailor

generate those

pex_binary

targets?

Before answering those, have you deployed ignores yet?: https://github.com/pantsbuild/pants/blob/891adbbad5be7b5dc21b2be97206e0a4cbf2ead0/pants.toml#L90-L108

You can also tell Pants to not generate for

pex_binary

with

[python].tailor_pex_binary_targets = false

(the subsystem is called

[python-setup]

in earlier Pants versions)

Docs for both here: + https://www.pantsbuild.org/docs/reference-tailor + https://www.pantsbuild.org/docs/reference-python

As to why pants tailor generates pex_binary targets for files, it is because it detects an entry point (

if __name__ == "__main__":

) in them. this is done here: https://github.com/pantsbuild/pants/blob/891adbbad5be7b5dc21b2be97206e0a4cbf2ead0/src/python/pants/backend/python/goals/tailor.py#L150

Gotcha, thanks a lot. So I think the answers are: 1. a BUILD file is generated at root because it detects a

.py

file there 2. pex binaries are generated because

main

are detected. And the solution to not have any unwanted updates is to configure the

tailor

section in the toml file, for each of the targets.