Poetry fails to install idna-ssl dependency with Wine: "ValueError: illegal environment variable name"

The context is similar to issue #147 (Wine on Linux), but I get a different error, when having no virtualenv enabled (the cause of #147), and when installing a particular package, idna-ssl:

Creating virtualenv whatever-py3.6 in C:\users\desbma\Local Settings\Application Data\pypoetry\Cache\virtualenvs
Using virtualenv: C:\users\desbma\Local Settings\Application Data\pypoetry\Cache\virtualenvs\whatever-py3.6
Updating dependencies
Resolving dependencies... (0.8s)


Package operations: 2 installs, 0 updates, 0 removals

Writing lock file

  - Installing idna (2.6)
  - Installing idna-ssl (1.0.1)
                                                                                
[VenvCommandError]                                               
Command ['pip', 'install', '--no-deps', '-r', 'C:\\users\\desbma\\Temp\\idna  
-ssl-1.0.1mbmbbw6xreqs.txt'] errored with the following output:               
Collecting idna-ssl==1.0.1 (from -r C:\users\desbma\Temp\idna-ssl-1.0.1mbmbb  
w6xreqs.txt (line 1))                                                         
  Downloading https://files.pythonhosted.org/packages/c4/3b/facf5a5009e577e7  
764e68a2af5ee25c63f41c78277260c2c42b8cfabf2e/idna-ssl-1.0.1.tar.gz            
    Error illegal environment variable name while executing command python s  
etup.py egg_info                                                              
Exception:                                                                    
Traceback (most recent call last):                                            
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\basecommand.py", line 215, in ma  
in                                                                            
    status = self.run(options, args)                                          
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\commands\install.py", line 324,   
in run                                                                        
    requirement_set.prepare_files(finder)                                     
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\req\req_set.py", line 380, in pr  
epare_files                                                                   
    ignore_dependencies=self.ignore_dependencies))                            
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\req\req_set.py", line 634, in _p  
repare_file                                                                   
    abstract_dist.prep_for_dist()                                             
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\req\req_set.py", line 129, in pr  
ep_for_dist                                                                   
    self.req_to_install.run_egg_info()                                        
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\req\req_install.py", line 439, i  
n run_egg_info                                                                
    command_desc='python setup.py egg_info')                                  
  File "c:\users\desbma\local settings\application data\pypoetry\Cache\virtu  
alenvs\whatever-py3.6\lib\site-packages\pip\utils\__init__.py", line 667, in  
 call_subprocess                                                              
    cwd=cwd, env=env)                                                         
  File "c:\Python36\lib\subprocess.py", line 709, in __init__                 
    restore_signals, start_new_session)                                       
  File "c:\Python36\lib\subprocess.py", line 997, in _execute_child           
    startupinfo)                                                              
ValueError: illegal environment variable name                                 
You are using pip version 9.0.1, however version 10.0.1 is available.         
You should consider upgrading via the 'python -m pip install --upgrade pip'   
command.                                                                      
                                                                                
Exception trace:
 c:\Python36\lib\site-packages\poetry\_vendor\cleo\application.py in run() at line 94
   status_code = self.do_run(input_, output_)
 c:\Python36\lib\site-packages\poetry\console\application.py in do_run() at line 86
   return super(Application, self).do_run(i, o)
 c:\Python36\lib\site-packages\poetry\_vendor\cleo\application.py in do_run() at line 197
   status_code = command.run(input_, output_)
 c:\Python36\lib\site-packages\poetry\console\commands\command.py in run() at line 77
   return super(BaseCommand, self).run(i, o)
 c:\Python36\lib\site-packages\poetry\_vendor\cleo\commands\base_command.py in run() at line 146
   status_code = self.execute(input_, output_)
 c:\Python36\lib\site-packages\poetry\_vendor\cleo\commands\command.py in execute() at line 107
   return self.handle()
 c:\Python36\lib\site-packages\poetry\console\commands\install.py in handle() at line 52
   return installer.run()
 c:\Python36\lib\site-packages\poetry\installation\installer.py in run() at line 75
   self._do_install(local_repo)
 c:\Python36\lib\site-packages\poetry\installation\installer.py in _do_install() at line 257
   self._execute(op)
 c:\Python36\lib\site-packages\poetry\installation\installer.py in _execute() at line 265
   getattr(self, '_execute_{}'.format(method))(operation)
 c:\Python36\lib\site-packages\poetry\installation\installer.py in _execute_install() at line 291
   self._installer.install(operation.package)
 c:\Python36\lib\site-packages\poetry\installation\pip_installer.py in install() at line 38
   self.run(*args)
 c:\Python36\lib\site-packages\poetry\installation\pip_installer.py in run() at line 63
   return self._venv.run('pip', *args, **kwargs)
 c:\Python36\lib\site-packages\poetry\utils\venv.py in run() at line 279
   raise VenvCommandError(e)

install [--no-dev] [--dry-run] [-E|--extras EXTRAS] [--develop DEVELOP]

Standalone script to reproduce: https://pastebin.com/raw/UNu9JL8g

The same dependency gets installed normally using Poetry on Linux, or pip on Wine.

[stuaxo]

Maybe this is just my setup, but I seem to have an env var whose name is an empty string

>>> import os
>>> os.environ['']
'Z:=Z:\\home\\stu\\Downloads'

I added the line env.pop('') to ~/.wine/drive_c/Python27/Lib/site-packages/pip/_internal/utils/misc.py

after:

    env = os.environ.copy()
    if extra_environ:
        env.update(extra_environ)

And pip seems to get quite a bit further for my own library, it might help here too.

[stuaxo]

Apologies for the noise, came across this through googling, should have read your env vars.