Windows embedable support

[karelv]

Issue

Installing virtualenv with pip install virtualenv should install the package.
I get error:

ModuleNotFoundError: No module named 'distlib'

Environment

Provide at least:

• OS: Win7 64bit

$ pip list
Package    Version
---------- -------
pip        20.0.2
setuptools 46.1.3
wheel      0.34.2

Python version: Python 3.8.2 (tags/v3.8.2:7b3ab59, Feb 25 2020, 23:03:10) [MSC v.1916 64 bit (AMD64)] on win32

Output of the virtual environment creation

Well output of installation process.

$ pip install virtualenv
Collecting virtualenv
  Using cached virtualenv-20.0.18-py2.py3-none-any.whl (4.6 MB)
Collecting appdirs<2,>=1.4.3
  Using cached appdirs-1.4.3-py2.py3-none-any.whl (12 kB)
Collecting distlib<1,>=0.3.0
  Using cached distlib-0.3.0.zip (571 kB)
    ERROR: Command errored out with exit status 1:
     command: 'c:\python382_64b\python.exe' -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'C:\\Users\\XXX\\AppData\\Local\\Temp\\pip-install-ms4c53bl\\distlib\\setup.py'"'"'; __file__='"'"'C:\\Users\\XXX\\AppData\\Local\\Temp\\pip-install-ms4c53bl\\distlib\\setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base 'C:\Users\XXX\AppData\Local\Temp\pip-install-ms4c53bl\distlib\pip-egg-info'
         cwd: C:\Users\XXX\AppData\Local\Temp\pip-install-ms4c53bl\distlib\
    Complete output (5 lines):
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "C:\Users\XXX\AppData\Local\Temp\pip-install-ms4c53bl\distlib\setup.py", line 14, in <module>
        import distlib
    ModuleNotFoundError: No module named 'distlib'
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.

[karelv]

Earlier version seems to work

$ pip install "virtualenv<20"
Collecting virtualenv<20
  Downloading virtualenv-16.7.10-py2.py3-none-any.whl (3.4 MB)
     |████████████████████████████████| 3.4 MB 50 kB/s
Installing collected packages: virtualenv
Successfully installed virtualenv-16.7.10

However it seems not to be able to create a virtualenv.

$ virtualenv.exe pyxxx
Using base prefix 'c:\\python382_32b'
Traceback (most recent call last):
  File "runpy.py", line 193, in _run_module_as_main
  File "runpy.py", line 86, in _run_code
  File "C:\python382_32b\Scripts\virtualenv.exe\__main__.py", line 7, in <module>
  File "c:\python382_32b\lib\site-packages\virtualenv.py", line 859, in main
    create_environment(
  File "c:\python382_32b\lib\site-packages\virtualenv.py", line 1161, in create_environment
    install_python(home_dir, lib_dir, inc_dir, bin_dir, site_packages=site_packages, clear=clear, symlink=symlink)
  File "c:\python382_32b\lib\site-packages\virtualenv.py", line 1467, in install_python
    writefile(site_filename_dst, SITE_PY)
  File "c:\python382_32b\lib\site-packages\virtualenv.py", line 431, in writefile
    with open(dest, "wb") as f:
FileNotFoundError: [Errno 2] No such file or directory: 'C:\\pyxxx\\python38.zip\\site.py'

[pfmoore]

I can't reproduce this. My versions of pip, setuptools and wheel are the same, this is in a fresh Python 3.8.0 venv. I am using Windows 10, but I'm not sure how that would make a difference here.

Your prompt is $, which is not usual for the standard Windows shells (cmd or powershell). Are you using an unusual environment such as cygwin? That's the only thing I can think of which could explain the difference with your results and mine.

[gaborbernat]

This feels like a pip issue; as it's related to installing the package. For now, we still need a reproduced of this. Can you provide more detailed information?

[pfmoore]

I just noticed:

FileNotFoundError: [Errno 2] No such file or directory: 'C:\\pyxxx\\python38.zip\\site.py'

It looks like you have the stdlib in a zip file. That's unusual - are you by any chance trying to use the embedded Python distribution? That's not intended for "general" use, and could be why you're getting issues here.

Please describe how you installed your Python environment, as it may be relevant.

[gaborbernat]

Closing for now as we've got no response to our request for more information. If you can acquire those please post the details and we'll reopen the issue.

[karelv]

It is indeed the embedded python version. My goal was to be try the new python version along my previous version, it appeared to me like the most obvious thing to do, however it seems not so obvious...
Thanks for having a look at this, so quickly! (I will have to find another way for trying new python version)

[gaborbernat]

How did you install an embedded Python?

[pfmoore]

@gaborbernat I was specifically talking about the windows embeddable package, which is available as a zipfile that can be unzipped anywhere.

The problem is that while it appears to work like "normal" Python, it's tuned specifically for embedding into your own application - so, for example, it doesn't include pip, and you need to do some config changes to get pip to work. It's not really a supported use of that distribution.

For virtualenv, I guess there is a question of whether you want to support setups where the standard library is zipped up and/or contains only .pyc files (both of which are true for the embedded distribution).

[gaborbernat]

Working only with pyc files is already supported. Them being zipped up is an interesting question; which boils down to the fact can we even support these without unzipping the entire library.