Poetry trips up with a `json.py` or `select.py` or other stdlib names in cwd

• 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: Ubuntu 18.04 LTS
• Poetry version: 0.12.10

Issue

poetry throws exception if theres a module in cwd conflicting with a stdlib one

to reproduce:

mkdir test && cd test
poetry init -n -q
touch json.py  # or {sys,os,platform,select}.py
poetry add requests  # or any poetry command

On Poetry 0.12.5 it raises:

[EnvCommandError]                                                           
Command /home/me/.cache/pypoetry/virtualenvs/test-py3.6/bin/python -c "im  
port json; import os; import platform; import sys; implementation = getattr(sys, 'imple  
mentation', None); iver = '{0.major}.{0.minor}.{0.micro}'.format(implementation.version  
) if implementation else '0'; implementation_name = implementation.name if implementati  
on else ''; env = {'implementation_name': implementation_name,'implementation_version':  
 iver,'os_name': os.name,'platform_machine': platform.machine(),'platform_release': pla  
tform.release(),'platform_system': platform.system(),'platform_version': platform.versi  
on(),'python_full_version': platform.python_version(),'platform_python_implementation':  
 platform.python_implementation(),'python_version': platform.python_version()[:3],'sys_  
platform': sys.platform,'version_info': sys.version_info[:3],};print(json.dumps(env))"                        
errored with the following output:                                                       
Traceback (most recent call last):                                                       
  File "<string>", line 1, in <module>                                                   
AttributeError: module 'json' has no attribute 'dumps'

On 0.12.10:

[JSONDecodeError]             
Expecting value: line 1 column 1 (char 0)

I can see the error comes from executing python -c, copying the command directly on bash, it does raises an exception but adding the -I : isolate Python from the user's environment (implies -E and -s) flag produces the right output.

Although naming top level modules with stdlib names is not best-practice, some names may not be immediately obvious (I was using select.py), and the error output on current poetry version is not helpful (even with -vvv, took me a while to pin down the error)

[naringas]

I bumped into a similar error with poetry 0.12.11 on mac os with homebrewed python 3.7

I managed to bypass it by erasing the entire the entire ~/Library/Caches/pypoetry folder and everything in it

[finswimmer]

I agree with @jtrakk. If python will find a module in the current working directory it will prefer it. So there is nothing poetry can do about it here.