import git fails when current working directory doesn't exist

[bluenote10]

Steps to reproduce:

$ mkdir /tmp/dir_to_be_deleted
$ cd /tmp/dir_to_be_deleted
$ rmdir /tmp/dir_to_be_deleted
$ python -c "import git"

Crashes with

Traceback (most recent call last):
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/__init__.py", line 87, in <module>
    refresh()
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/__init__.py", line 76, in refresh
    if not Git.refresh(path=path):
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/cmd.py", line 243, in refresh
    cls().version()
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/cmd.py", line 585, in <lambda>
    return lambda *args, **kwargs: self._call_process(name, *args, **kwargs)
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/cmd.py", line 1124, in _call_process
    return self.execute(call, **exec_kwargs)
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/cmd.py", line 782, in execute
    cwd = self._working_dir or os.getcwd()
FileNotFoundError: [Errno 2] No such file or directory

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/me/.virtualenvs/default/lib/python3.8/site-packages/git/__init__.py", line 89, in <module>
    raise ImportError('Failed to initialize: {0}'.format(exc)) from exc
ImportError: Failed to initialize: [Errno 2] No such file or directory

In general os.getcwd() needs to guarded against FileNotFoundError because of the possibility that there is no valid working directory.

GitPython version: 3.1.18

This is certainly not a big issue, but it can be very confusing, and there is (probabaly) not theoretical reason why GitPython cannot work in this case.

[Byron]

Thanks for the report. I understand that it's probably a bit strange that it needs the CWD to just be imported.
AFAIK it tries to get the git version string while initializing some global state. Maybe that could be done lazily instead to avoid this issue.

[bluenote10]

Yes lazily would probably be the most elegant solution, because it is in the Python-best-practices-spirit of not executing anything that can throw at import time.

If you want a quick-and-dirty solution though, it should also be sufficient to replace

GitPython/git/cmd.py

Line 784 in ea1a03a

cwd = self._working_dir or os.getcwd()

with

try:
    cwd = self._working_dir or os.getcwd()
except FileNotFoundError:
    cwd = None

This should work, because cwd is only used in subprocess.Popen and passing cwd=None would be fine. If running other git commands than version that actually require a cwd, git would error anyway because of the "broken" working directory.

[Byron]

Thanks a lot for the suggestion. Since it was added as is I assume this particular issue will be resolved. Maybe there are other stumbling blocks though, and if so please feel free to post here so the issue can be reopened.