How to change build directory in setuptools

Question

I have a repo that I'm trying to modify to be deployable as a python package. Unfortunately, the root of the repository has a file named BUILD that cannot be changed due to existing CI integrations. As a result, when I attempt to pip install or python setup.py bdist_wheel or any other permutation of using setuptools it fails because it cannot create a build/ directory.

How can I change that build directory to be _build/ or something non-conflicting?

I've tried several things like python setup.py build -b _build which works for the build step in isolation, but I can't find an equivalent command line argument or setup.py option that will let me change it for all of the subcommands of bdist_wheel. There seem to be a lot of moving pieces that expect to be able to create a build directory at some point or reference it, and I haven't been able to track them all down.

Answer 1

Override build_base in build command; it's used in all other distutils/setuptools commands:

import distutils.command.build

# Override build command
class BuildCommand(distutils.command.build.build):
    def initialize_options(self):
        distutils.command.build.build.initialize_options(self)
        self.build_base = 'my-special-build-dir'

setup(
    …
    cmdclass={"build": BuildCommand},
    …
)