WPS335 rejects list-of-lists comprehensions

What’s wrong

I’m trying to produce a list of lists but getting a false-positive warning:

WPS335 Found incorrect `for` loop iter type
 ([x] for x in (1, 2, 3))
 ^

Here is a code

[ l for l in
  ([x] for x in (1, 2, 3))
]

How it should be

It should be possible to produce the list of lists.

Flake8 version and plugins

{
  "dependencies": [],
  "platform": {
    "python_implementation": "CPython",
    "python_version": "3.8.8",
    "system": "Linux"
  },
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pip information

pip 20.2.3 from /home/astynax/Projects/hexlet/hexlet-exercise-kit/exercises/course-python-declarative-programming/python_declarative_programming_list_comprehensions_exercise/.venv/lib/python3.8/site-packages/pip (python 3.8) astor==0.8.1 attrs==21.2.0 bandit==1.7.0 darglint==1.8.0 docutils==0.17.1 eradicate==2.0.0 flake8==3.9.2 flake8-bandit==2.1.2 flake8-broken-line==0.3.0 flake8-bugbear==20.11.1 flake8-commas==2.0.0 flake8-comprehensions==3.5.0 flake8-debugger==4.0.0 flake8-docstrings==1.6.0 flake8-eradicate==1.0.0 flake8-isort==4.0.0 flake8-polyfill==1.0.2 flake8-quotes==3.2.0 flake8-rst-docstrings==0.0.14 flake8-string-format==0.3.0 gitdb==4.0.7 GitPython==3.1.14 isort==5.8.0 mccabe==0.6.1 pbr==5.6.0 pep8-naming==0.11.1 pycodestyle==2.7.0 pydocstyle==6.0.0 pyflakes==2.3.1 Pygments==2.9.0 PyYAML==5.4.1 restructuredtext-lint==1.3.2 six==1.16.0 smmap==4.0.0 snowballstemmer==2.1.0 stevedore==3.3.0 testfixtures==6.17.1 typing-extensions==3.10.0.0 wemake-python-styleguide==0.15.2

OS information

Ubuntu Linux 16.04

[astynax]

O, rly? This is just a minimal example! And why it’s invalid? One may want to iterate from the subcomprehension! Here is a real example if you want:

def non_empty_truths(list_of_lists):
    return [
        truths for truths in
        ([elem for elem in one_list if elem]  # noqa: WPS335
         for one_list in list_of_lists
         )
        if truths
    ]

And here should be the lists! Not tuples, not genexps, the lists!

[surya-kodeti]

Hi there, I’m a newbie searching for an easy-to-solve issue this seems to be a good start for me. If this is still open, please guide me on this