poetry env use fails with NameError: name 'WindowsPath' is not defined

• I am on the latest Poetry version.
• I have searched the issues of this repo and believe that this is not a duplicate.
• If an exception occurs when executing a command, I executed it again in debug mode (-vvv option).

• OS version and name: Windows 10 Pro
• Poetry version: 1.0.10
• Link of a Gist with the contents of your pyproject.toml file: https://gist.github.com/moochannel/f26598d0d763cbadd7ca44e89bc917c0

Issue

When I run poetry env use "C:\Program Files\Python37\python.exe" in a directory without a virtual environment, it fails with NameError: name 'WindowsPath' is not defined.

(In empty directory C:\Users\xxxx\poetrytest)
> poetry init
> poetry env use "C:\Program Files\Python37\python.exe"

Creating virtualenv poetrytest in C:\Users\xxxx\poetrytest\.venv
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'WindowsPath' is not defined

[EnvCommandError]
Command ['python', '-'] errored with the following return code 1, and output:
'python' is not recognized as an internal or external command,
operable program or batch file.
input was : import sys

if hasattr(sys, "real_prefix"):
    print(sys.real_prefix)
elif hasattr(sys, "base_prefix"):
    print(sys.base_prefix)
else:
    print(sys.prefix)

exit status 1

CREATE_VENV_COMMAND.format(path)) in EnvManager.build_venv converts path to WindowsPath(path), but CREATE_VENV_COMMAND doesn’t contain pathlib.WindowsPath. So it results in an error.

My workaround here. I suppose the path should be converted from WindowsPath to str before it passed to CREATE_VENV_COMMAND.format(path)).

--- env.py.bak  2020-07-22 06:30:05.245529100 +0900
+++ env.py      2020-07-22 14:20:24.012698600 +0900
@@ -669,7 +669,7 @@
                     stdin=subprocess.PIPE,
                     shell=True,
                 )
-                p.communicate(encode(CREATE_VENV_COMMAND.format(path)))
+                p.communicate(encode(CREATE_VENV_COMMAND.format(str(path))))
             except CalledProcessError as e:
                 raise EnvCommandError(e)

After patching this, the command runs fine.

> poetry env use "C:\Program Files\Python37\python.exe"
Creating virtualenv poetrytest in C:\Users\xxxx\poetrytest\.venv
Using virtualenv: C:\Users\xxxx\poetrytest\.venv

[rcoulter13]

Followup: the newest version requires the syntax “poetry self update --preview” in order to work, but even at that it denies permission even if PowerShell runs with administrator access. Every time it gets really close to upgrading but it always runs into a file where access is denied. I’ll keep exploring but so far it looks like uninstalling the current version of poetry and then downloading the desired version might be the best workaround. If anyone knows of a better solution please let me know. Thanks!

[moochannel]

@abn Thank you for your quick reply. I tried the develop branch with pip install git+https://github.com/python-poetry/poetry.git@develop. The problem has been gone😉

Since poetry -V shows as 1.1.0a3 in the develop branch, I think this will be fixed in the next 1.1.0x release. Will this change apply to 1.0.x?