With MacOS and PyPy installation fails: AttributeError: 'LooseVersion' object has no attribute 'version'

[bhy]

On MacOS 10.14, PyPy3.6-7.1.1 installation fails:

$ pip3 install pandas
Collecting pandas
  Using cached https://files.pythonhosted.org/packages/b2/4c/b6f966ac91c5670ba4ef0b0b5613b5379e3c7abdfad4e7b89a87d73bae13/pandas-0.24.2.tar.gz
    ERROR: Complete output from command python setup.py egg_info:
    ERROR: Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/private/var/folders/50/8j9r2pm93n15lw18936l7zkc0000gn/T/pip-install-96rmqzke/pandas/setup.py", line 438, in <module>
        if python_target < '10.9' and current_system >= '10.9':
      File "/Users/haoyu/.pyenv/versions/pypy3.6-7.1.1/lib-python/3/distutils/version.py", line 52, in __lt__
        c = self._cmp(other)
      File "/Users/haoyu/.pyenv/versions/pypy3.6-7.1.1/lib-python/3/distutils/version.py", line 335, in _cmp
        if self.version == other.version:
    AttributeError: 'LooseVersion' object has no attribute 'version'

A workaround is to install with:
MACOSX_DEPLOYMENT_TARGET=10.14.4 pip3 install pandas

The cause for this is that in pandas setup.py, get_config_var('MACOSX_DEPLOYMENT_TARGET') will return None on PyPy, while a version number like 10.9 is expected. (See https://github.com/pandas-dev/pandas/blob/master/setup.py#L453).

[simonjayhawkins]

@bhy Thanks for the report.

PyPy is not included in our CI or distributed binaries for PyPy. (not tested / officially supported).

May be worth raising this on the PyPy issue tracker. Closing this as we don't make any guarantees about PyPy.

[TomAugspurger]

@simonjayhawkins we still accept patches for PyPy compatibility. This may be on us, but that's not clear yet.

@bhy is that never defined for pypy? If so, do you know why?

cc @robbuckley just as an FYI.

[simonjayhawkins]

This may be on us, but that's not clear yet.

@TomAugspurger : ok. i'll reopen for now.

[robbuckley]

a quick fix could be to change the indicated line from

if is_platform_mac():
    if 'MACOSX_DEPLOYMENT_TARGET' not in os.environ:
        current_system = LooseVersion(platform.mac_ver()[0])
        python_target = LooseVersion(
            get_config_var('MACOSX_DEPLOYMENT_TARGET'))
        if python_target < '10.9' and current_system >= '10.9':
            os.environ['MACOSX_DEPLOYMENT_TARGET'] = '10.9'

to

if is_platform_mac():
    if 'MACOSX_DEPLOYMENT_TARGET' not in os.environ:
        current_system = LooseVersion(platform.mac_ver()[0])
        python_target = LooseVersion(
            get_config_vars().get('MACOSX_DEPLOYMENT_TARGET', current_system))
        if python_target < '10.9' and current_system >= '10.9':
            os.environ['MACOSX_DEPLOYMENT_TARGET'] = '10.9'

Also changing this line:

pandas/setup.py

Line 14 in 7629a18

from distutils.sysconfig import get_config_var

to:

from distutils.sysconfig import get_config_vars

Note the additonal 's'. This shouldnt break CPython (caveat: no tests done yet!). I have no easy way to test this on PyPy, but Im happy to submit a patch and test on CPython if that helps.

[TomAugspurger]

yeah, that seems like an option @robbuckley. But let's wait to hear more from @bhy to better understand what's going wrong with PyPy here before we change anything.

[bhy]

@TomAugspurger I never saw it defined across the versions of PyPy I tried with (6.0 and 7.1). I'm not familiar with PyPy development, but their document mentions (http://doc.pypy.org/en/latest/cpython_differences.html):

The get_config_vars method of sysconfig and distutils.sysconfig are not complete. On POSIX platforms, CPython fishes configuration variables from the Makefile used to build the interpreter. PyPy should bake the values in during compilation, but does not do that yet.

[TomAugspurger]

Thanks. Given that I think that @robbuckley's proposal is reasonable. @bhy can you test it out locally, and perhaps submit a PR?