Pip not picking up a custom install cmdclass

I ran into this problem just now. It looks like there are many different commands that pip install my-package can translate into.

1. setup.py install
2. setup.py egg_info
3. setup.py develop

So you need to handle each of these different cases.

from setuptools.command.install import install
from setuptools.command.develop import develop
from setuptools.command.egg_info import egg_info

'''
BEGIN CUSTOM INSTALL COMMANDS
These classes are used to hook into setup.py's install process. Depending on the context:
$ pip install my-package

Can yield `setup.py install`, `setup.py egg_info`, or `setup.py develop`
'''


def custom_command():
    import sys
    if sys.platform in ['darwin', 'linux']:
        os.system('./custom_command.sh')


class CustomInstallCommand(install):
    def run(self):
        install.run(self)
        custom_command()


class CustomDevelopCommand(develop):
    def run(self):
        develop.run(self)
        custom_command()


class CustomEggInfoCommand(egg_info):
    def run(self):
        egg_info.run(self)
        custom_command()

'''
END CUSTOM INSTALL COMMANDS 
'''

setup(
    ...
    cmdclass={
        'install': CustomInstallCommand,
        'develop': CustomDevelopCommand,
        'egg_info': CustomEggInfoCommand,
    },
    ...
)