Pipenv: Running pipenv in `/` causes a stacktrace `AssertionError` on `assert self.name`

[asottile]

Issue description

A stacktrace is produced when running in /, this same stacktrace appears in #2306 but there was no resolution/fix there.

Expected result

No stacktrace, perhaps a useful error message, or perhaps when in / it could use a name of 'root' and "just work".

Actual result

$ docker run --rm -ti python:3.5-slim bash -c 'pip install pipenv && pipenv install pytest'
Collecting pipenv
  Downloading https://files.pythonhosted.org/packages/13/b4/3ffa55f77161cff9a5220f162670f7c5eb00df52e00939e203f601b0f579/pipenv-2018.11.26-py3-none-any.whl (5.2MB)
    100% |████████████████████████████████| 5.2MB 6.9MB/s 
Collecting virtualenv-clone>=0.2.5 (from pipenv)
  Downloading https://files.pythonhosted.org/packages/16/9d/6419a4f0fe4350db7fdc01e9d22e949779b6f2d2650e4884aa8aededc5ae/virtualenv_clone-0.4.0-py2.py3-none-any.whl
Collecting certifi (from pipenv)
  Downloading https://files.pythonhosted.org/packages/9f/e0/accfc1b56b57e9750eba272e24c4dddeac86852c2bebd1236674d7887e8a/certifi-2018.11.29-py2.py3-none-any.whl (154kB)
    100% |████████████████████████████████| 163kB 16.2MB/s 
Requirement already satisfied: pip>=9.0.1 in /usr/local/lib/python3.5/site-packages (from pipenv) (18.1)
Requirement already satisfied: setuptools>=36.2.1 in /usr/local/lib/python3.5/site-packages (from pipenv) (40.6.3)
Collecting virtualenv (from pipenv)
  Downloading https://files.pythonhosted.org/packages/6a/d1/e0d142ce7b8a5c76adbfad01d853bca84c7c0240e35577498e20bc2ade7d/virtualenv-16.2.0-py2.py3-none-any.whl (1.9MB)
    100% |████████████████████████████████| 1.9MB 13.6MB/s 
Installing collected packages: virtualenv-clone, certifi, virtualenv, pipenv
Successfully installed certifi-2018.11.29 pipenv-2018.11.26 virtualenv-16.2.0 virtualenv-clone-0.4.0
Creating a virtualenv for this project…
Pipfile: /Pipfile
Using /usr/local/bin/python (3.5.6) to create virtualenv…
⠸ Creating virtual environment...Already using interpreter /usr/local/bin/python
Using base prefix '/usr/local'
New python executable in /root/.local/share/virtualenvs/-x-v5uFv0/bin/python
Installing setuptools, pip, wheel...
done.

✔ Successfully created virtual environment! 
Virtualenv location: /root/.local/share/virtualenvs/-x-v5uFv0
Creating a Pipfile for this project…
Traceback (most recent call last):
  File "/usr/local/bin/pipenv", line 11, in <module>
    sys.exit(cli())
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/core.py", line 764, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/core.py", line 717, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/core.py", line 956, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/decorators.py", line 64, in new_func
    return ctx.invoke(f, obj, *args, **kwargs)
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python3.5/site-packages/pipenv/vendor/click/decorators.py", line 17, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/usr/local/lib/python3.5/site-packages/pipenv/cli/command.py", line 254, in install
    editable_packages=state.installstate.editables,
  File "/usr/local/lib/python3.5/site-packages/pipenv/core.py", line 1741, in do_install
    pypi_mirror=pypi_mirror,
  File "/usr/local/lib/python3.5/site-packages/pipenv/core.py", line 609, in ensure_project
    validate=validate, skip_requirements=skip_requirements, system=system
  File "/usr/local/lib/python3.5/site-packages/pipenv/core.py", line 320, in ensure_pipfile
    project.create_pipfile(python=python)
  File "/usr/local/lib/python3.5/site-packages/pipenv/project.py", line 697, in create_pipfile
    config_parser = ConfigOptionParser(name=self.name)
  File "/usr/local/lib/python3.5/site-packages/pipenv/patched/notpip/_internal/cli/parser.py", line 142, in __init__
    assert self.name
AssertionError

Steps to replicate

The actual result above contains a single command which replicates this issue

---

$ pipenv --support

Pipenv version: '2018.11.26'

Pipenv location: '/usr/local/lib/python3.5/site-packages/pipenv'

Python location: '/usr/local/bin/python'

Python installations found:

• 3.5.6: /usr/local/bin/python3.5m
• 3.5.6: /usr/local/bin/python3

PEP 508 Information:

{'implementation_name': 'cpython',
 'implementation_version': '3.5.6',
 'os_name': 'posix',
 'platform_machine': 'x86_64',
 'platform_python_implementation': 'CPython',
 'platform_release': '4.9.125-linuxkit',
 'platform_system': 'Linux',
 'platform_version': '#1 SMP Fri Sep 7 08:20:28 UTC 2018',
 'python_full_version': '3.5.6',
 'python_version': '3.5',
 'sys_platform': 'linux'}

System environment variables:

• PYTHON_VERSION
• TERM
• _
• PYTHONFINDER_IGNORE_UNSUPPORTED
• PYTHON_PIP_VERSION
• PIP_SHIMS_BASE_MODULE
• PYTHONDONTWRITEBYTECODE
• PWD
• PIP_PYTHON_PATH
• HOSTNAME
• HOME
• PIP_DISABLE_PIP_VERSION_CHECK
• SHLVL
• PATH
• GPG_KEY
• LANG

Pipenv–specific environment variables:

Debug–specific environment variables:

• PATH: /usr/local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
• LANG: C.UTF-8
• PWD: /

---

[hroncok]

This is where it comes from:

https://github.com/pypa/pipenv/blob/c4341a7d5dcd2bdb6f04de77fe715ce1ed78abe3/pipenv/project.py#L217-L221

[Marviel]

I ran into this when running in a docker container for #3504 -- had to specify a working directory via docker's -w flag to make it work (i.e. docker run -w '/root/' -it python:3 ..... Just recording the information for any strugglers in the same boat.