ImportError with --looponfail and "python -m pytest" if project is not installed

For some reason I am getting an ImportError for the project itself when using --looponfail with python -m pytest, and the project not being installed via pip install -e ..

The workaround is to either pip install -e . the project, or use -o django_find_project=1, which will massage sys.path based on the manage.py it finds.

This does not happen when omitting --looponfail, so there appears to be something different in this regard in how sys.path is handled.

% python -m pytest -o rsyncdirs=project --tx ssh=gw0.XXX.eu-west-1.compute.internal.xdistnode//chdir=/srv/project/src --dist=load '-o rsyncdirs=project' --looponfail --cov=project --cov-report=term-missing:skip-covered --cov-report=xml --run-slow-tests --ff
Traceback (most recent call last):                                                                                                                                                            
  File "…/pyenv/3.6.6/lib/python3.6/runpy.py", line 193, in _run_module_as_main                                                                                          
    "__main__", mod_spec)                                                                                                                                                                     
  File "…/pyenv/3.6.6/lib/python3.6/runpy.py", line 85, in _run_code                                                                                                     
    exec(code, run_globals)                                                                                                                                                                   
  File "…/project/.venv/lib/python3.6/site-packages/pytest.py", line 68, in <module>                                                                              
    raise SystemExit(pytest.main())                                                                                                                                                           
  File "…/project/.venv/lib/python3.6/site-packages/_pytest/config/__init__.py", line 65, in main                                                                 
    return config.hook.pytest_cmdline_main(config=config)                                                                                                                                     
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/hooks.py", line 258, in __call__                                                                       
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)                                                                                                                   
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec                                                                     
    return self._inner_hookexec(hook, methods, kwargs)                                                                                                                                        
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>                                                                      
    firstresult=hook.spec_opts.get('firstresult'),                                                                                                                                            
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/callers.py", line 201, in _multicall                                                                   
    return outcome.get_result()                                                                                                                                                               
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/callers.py", line 76, in get_result                                                                    
    raise ex[1].with_traceback(ex[2])                                                                                                                                                         
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/callers.py", line 180, in _multicall                                                                   
    res = hook_impl.function(*args)                                                                                                                                                           
  File "…/Vcs/pytest-xdist/xdist/looponfail.py", line 36, in pytest_cmdline_main                                                                                                   
    looponfail_main(config)                                                                                                                                                                   
  File "…/Vcs/pytest-xdist/xdist/looponfail.py", line 45, in looponfail_main
    try:
  File "…/Vcs/pytest-xdist/xdist/looponfail.py", line 119, in loop_once
    result = self.runsession()
  File "…/Vcs/pytest-xdist/xdist/looponfail.py", line 108, in runsession
    return self.channel.receive()
  File "…/project/.venv/lib/python3.6/site-packages/execnet/gateway_base.py", line 737, in receive
    raise self._getremoteerror() or EOFError()
execnet.gateway_base.RemoteError: Traceback (most recent call last):
  File "…/Vcs/pytest-django/pytest_django/plugin.py", line 114, in _handle_import_error
    yield
  File "…/Vcs/pytest-django/pytest_django/plugin.py", line 259, in pytest_load_initial_conftests
    dj_settings.DATABASES
  File "…/project/.venv/lib/python3.6/site-packages/django/conf/__init__.py", line 56, in __getattr__
    self._setup(name)
  File "…/project/.venv/lib/python3.6/site-packages/django/conf/__init__.py", line 43, in _setup
    self._wrapped = Settings(settings_module)
  File "…/project/.venv/lib/python3.6/site-packages/django/conf/__init__.py", line 106, in __init__
    mod = importlib.import_module(self.SETTINGS_MODULE)
  File "…/pyenv/3.6.6/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 941, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 953, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'project'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "…/project/.venv/lib/python3.6/site-packages/execnet/gateway_base.py", line 1076, in executetask
    function(channel, **kwargs)
  File "<remote exec>", line 20, in init_worker_session
  File "…/project/.venv/lib/python3.6/site-packages/_pytest/config/__init__.py", line 646, in fromdictargs
    config.parse(args, addopts=False)
  File "…/project/.venv/lib/python3.6/site-packages/_pytest/config/__init__.py", line 782, in parse
    self._preparse(args, addopts=addopts)
  File "…/project/.venv/lib/python3.6/site-packages/_pytest/config/__init__.py", line 744, in _preparse
    early_config=self, args=args, parser=self._parser
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/hooks.py", line 258, in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/callers.py", line 201, in _multicall
    return outcome.get_result()
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/callers.py", line 76, in get_result
    raise ex[1].with_traceback(ex[2])
  File "…/project/.venv/lib/python3.6/site-packages/pluggy/callers.py", line 180, in _multicall
    res = hook_impl.function(*args)
  File "…/Vcs/pytest-django/pytest_django/plugin.py", line 259, in pytest_load_initial_conftests
    dj_settings.DATABASES
  File "…/pyenv/3.6.6/lib/python3.6/contextlib.py", line 99, in __exit__
    self.gen.throw(type, value, traceback)
  File "…/Vcs/pytest-django/pytest_django/plugin.py", line 118, in _handle_import_error
    raise ImportError(msg)
ImportError: No module named 'project'

pytest-django did not search for Django projects since it is disabled in the configuration ("django_find_project = false")

Version v1.22.5-1-g96af694

Start with xdist/looponfail.py, especially looponfail_main, loop_once, and runsession, and compare worker startup with normal python -m pytest behavior. Read the referenced pytest_django/plugin.py path and reproduce the reported command without installing the project. Done means loop-on-fail handles the project import consistently without breaking the documented django_find_project workaround.