Poetry shows `astroid` has two dependencies while pip says there's four

• 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 18.04.4 LTS x86_64

• Python version: 3.6.11 (pyenv)

• Poetry version: 1.1.0.b2

• Link of a Gist with the contents of your pyproject.toml file: Same as in this issue

Issue

Tried running pylint, it failed because it’s dependency astroid could not find its dependency wrapt installed. Found that poetry show astroid doesn’t list wrapt as its dependency, while pip show does.

Step by step (these all got run sequentially):

Install a fresh venv (I destroyed it to check whether I can replicate this in a fresh one).

➜  mypackage IN-3484-functional-tests ✗ poetry install                                                                                 
Creating virtualenv service-mypackage-4v1lnku2-py3.6 in /home/snejus/.cache/pypoetry/virtualenvs
Installing dependencies from lock file

Package operations: 54 installs, 0 updates, 0 removals
  ...

  - Installing pydantic (1.6.1)
  - Installing pylint (2.5.3)
  - Installing pytest-cov (2.10.0)
  - Installing pytest-randomly (3.4.1)
  - Installing python-dateutil (2.8.1)
  - Installing safety (1.9.0)

Installing the current project: service-mypackage (4.4.0)                                                                       /1m-3.2s

try running pylint

➜  mypackage IN-3484-functional-tests ✗ poetry run pylint src/service/mypackage
Traceback (most recent call last):
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/bin/pylint", line 8, in <module>
    sys.exit(run_pylint())
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/pylint/__init__.py", line 19,
    from pylint.lint import Run as PylintRun
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/pylint/lint/__init__.py", line
    from pylint.lint.check_parallel import check_parallel
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/pylint/lint/check_parallel.py"
    from pylint import reporters
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/pylint/reporters/__init__.py",
    from pylint import utils
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/pylint/utils/__init__.py", lin
    from pylint.utils.ast_walker import ASTWalker
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/pylint/utils/ast_walker.py", l
    from astroid import nodes
  File "/home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages/astroid/__init__.py", line 44,
    import wrapt
ModuleNotFoundError: No module named 'wrapt'                                                                                           /0.9s

poetry show

➜  mypackage IN-3484-functional-tests ✗ poetry show pylint
name         : pylint
version      : 2.5.3
description  : python code static checker

dependencies
 - astroid >=2.4.0,<=2.5
 - isort >=4.2.5,<5
 - mccabe >=0.6,<0.7
 - toml >=0.7.1
 - colorama *

➜  mypackage IN-3484-functional-tests ✗ poetry show astroid
name         : astroid
version      : 2.4.2
description  : An abstract syntax tree for Python with inference support.

dependencies
 - lazy-object-proxy >=1.4.0,<1.5.0
 - typed-ast >=1.4.0,<1.5

pip show

➜  mypackage IN-3484-functional-tests ✗ poetry run pip show astroid
Name: astroid
Version: 2.4.2
Summary: An abstract syntax tree for Python with inference support.
Home-page: https://github.com/PyCQA/astroid
Author: Python Code Quality Authority
Author-email: [e-mail]
License: LGPL
Location: /home/snejus/.cache/pypoetry/virtualenvs/service-mypackage-4v1lnku2-py3.6/lib/python3.6/site-packages
Requires: wrapt, lazy-object-proxy, typed-ast, six
Required-by: pylint

Looks like poetry skipped wrapt and six.

and poetry version just for completeness

➜  mypackage IN-3484-functional-tests ✗ poetry self --version
Poetry version 1.1.0b2                                                                                                                 /0.9s

[abn]

This was resolved with 1.1.0b3.

[abn]

The root cause of this issue is the parsing of package requirements for astroid.

https://github.com/PyCQA/astroid/blob/25384d4bebf0187b6704c818c7df64945793362c/astroid/__pkginfo__.py#L29-L31

My comment above was with poetry development installation using a development branch with poetry-core@master, hence why it works.

The parsing issue was resolved with python-poetry/poetry-core#55 and python-poetry/poetry-core#56.