python3-32 -m virtualenv .venv creates a 64-bit virtual environment

[mayeut]

• [x] OS and pip list output Running on macOS 10.14.6, official python.org installer of python 3.7.5 (macOS 64-bit/32-bit installer) python3.7-32 - m pip list

  Package            Version    Location                       
  ------------------ ---------- -------------------------------
  atomicwrites       1.3.0      
  attrs              19.1.0     
  auditwheel         2.1.2.dev8 /Users/Matt/Dev/pypa/auditwheel
  cibuildwheel       0.11.1     
  Click              7.0        
  cycler             0.10.0     
  delocate           0.7.4      
  filelock           3.0.12     
  importlib-metadata 0.23       
  incremental        17.5.0     
  Jinja2             2.10.3     
  kiwisolver         1.0.1      
  MarkupSafe         1.1.1      
  matplotlib         3.0.3      
  more-itertools     7.0.0      
  nose               1.3.7      
  numpy              1.16.2     
  packaging          19.2       
  pip                19.2.3     
  pluggy             0.13.0     
  py                 1.8.0      
  pyelftools         0.25       
  pyparsing          2.4.0      
  pytest             4.4.1      
  python-dateutil    2.8.0      
  setuptools         41.6.0     
  six                1.12.0     
  spam               0.1.0      
  toml               0.10.0     
  towncrier          19.2.0     
  tox                3.14.0     
  typing             3.6.6      
  virtualenv         16.7.7     
  wheel              0.31.1     
  zipp               0.6.0

• [x] Minimal reproducible example or detailed descriptions

  Matt$ python3.7-32 -m virtualenv ../cibuildwheel-venv-32
  Using base prefix '/Library/Frameworks/Python.framework/Versions/3.7'
  New python executable in /Users/Matt/Dev/cibuildwheel-venv-32/bin/python3.7-32
  Also creating executable in /Users/Matt/Dev/cibuildwheel-venv-32/bin/python
  Installing setuptools, pip, wheel...
  done.
  Matt$ source ../cibuildwheel-venv-32/bin/activate
  (cibuildwheel-venv-32) Matt$ python -V
  Python 3.7.5
  (cibuildwheel-venv-32) Matt$ python -c 'import sys; print(sys.maxsize)'
  9223372036854775807
  (cibuildwheel-venv-32) Matt$ deactivate 

The venv module works on 3.7 but does not exist on python 2.7 and so, is not an option at the moment

Matt$ python3.7-32 -m venv ../cibuildwheel-venv-32
Matt$ source ../cibuildwheel-venv-32/bin/activate
(cibuildwheel-venv-32) Matt$ python -V
Python 3.7.5
(cibuildwheel-venv-32) Matt$ python -c 'import sys; print(sys.maxsize)'
2147483647

One difference I can see between the 2 modules is that venv creates symlinks while virtualenv creates a copy. The copy seems to be from the dual-architecture python instead of the single i386 python.

[mayeut]

Replacing https://github.com/pypa/virtualenv/blob/43ccf4a14bb74b0119b49d025d200d927151e229/virtualenv.py#L1623

By :

        if '-32' in os.path.basename(py_executable):
            try:
                call_subprocess(["lipo", original_python, "-thin", "i386", "-output", py_executable])
            except Exception:
                logger.fatal("Could not call lipo -- you must " "have Apple's development tools installed")
                raise
        else:
            shutil.copy(original_python, py_executable)

after macOS framework detection seems to do the trick.

[mayeut]

The trick does not seem to work for python2.

[gaborbernat]

I don't think this is an issue anymore, and if so please check if with the rewrite branch it still is.

[mayeut]

Still an issue on master branch, not on rewrite branch.

[gaborbernat]

Then will be fixed once the rewrite lands.