[Distutils] Setuptools/Distribute - using from a "non-installed" location

[Daniel Holth]

On Thu, Feb 28, 2013 at 3:26 PM, Paul Moore <p.f.moore at gmail.com> wrote:
> For some scripts I am writing, I want to be able to run a package's
> setup.py using subprocess.check_call(). However, the python
> installation I'm using may not have setuptools/distribute installed,
> and yet I want to correctly process setup.py files which rely on
> setuptools. Is there any way of setting things up so that the Python
> subprocess can use a local, non-installed, copy of setuptools or
> distribute for the setup.py run? I've tried setting PYTHONPATH, but
> that doesn't seem to work - probably because directories on PYTHONPATH
> do not have .pth files processed.
>
> To clarify, what I'm doing is:
>
> here = os.path.abspath(os.path.dirname(__file__))
> # setuptools is available in os.path.join(here, 'setuptools')
> # setuptools.pth and easy-install.pth are in here
>
> os.environ[PYTHONPATH] = here # this doesn't work
> setup_py = <the setup.py file>
> setup_dir = os.path.abspath(os.path.dirname(setup_py))
> subprocess.check_call([sys.executable, 'setup.py', 'install'] +
> special_install_options, cwd=setup_dir)
>
> The point of this is that I want to write a script to build wheels
> from sdists, but I don't want to require the user to install
> setuptools just for the build step.
>
> Does anyone have any suggestions?
> Paul

Look at site.py, specifically site.addsitedir(sitedir, known_paths=None)