Make C0412: Imports from package are not grouped, compatible with isort

[Pierre-Sassoulas]

Description

C0412 and isort are incompatible when there is a mix of from x import y and import x. For example this is what isort want :

import astroid
import isort
from astroid import are_exclusive, decorators
from astroid.modutils import get_module_part, is_standard_module

But Pylint output a C0412 for the previous code and would want something like this :

import isort
import astroid
from astroid import are_exclusive, decorators
from astroid.modutils import get_module_part, is_standard_module

Possible solutions

• We could modify C0412 and take grouped import into account by import type (import x styled import grouped together, and from x import y styled import grouped together, instead of all import from a package grouped together).
• Or we could still take this problem into account but by displaying another message than C0412 (Possibly : "Mixed type of importation, choose a style between import x and and from x import y").

[PCManticore]

@Pierre-Sassoulas I'd be inclined to have the first solution. Also with what versions are you reproducing this bug? I can't with latest pylint and isort.

[Pierre-Sassoulas]

Isort was version 4.3.13 and pylint latest unreleased from last week (2.4.0 ?). I was able to reproduce with pylint 2.3.0 and isort 4.3.15 :

$ cat isort_compatible.py 

import astroid
import isort
from astroid import are_exclusive, decorators
from astroid.modutils import get_module_part, is_standard_module

$ cat pylint_compatible.py 

import isort
import astroid
from astroid import are_exclusive, decorators
from astroid.modutils import get_module_part, is_standard_module

$ isort isort_compatible.py --check-only 

# Nothing happen so it's sorted according to isort

$ ✘ isort pylint_compatible.py --check-only 

ERROR: /home/pierre/workspace/pylint/pylint_compatible.py Imports are incorrectly sorted.

 $ ✘ pylint isort_compatible.py

************* Module isort_compatible
isort_compatible.py:1:0: W0611: Unused import astroid (unused-import)
isort_compatible.py:2:0: W0611: Unused import isort (unused-import)
isort_compatible.py:3:0: W0611: Unused are_exclusive imported from astroid (unused-import)
isort_compatible.py:3:0: W0611: Unused decorators imported from astroid (unused-import)
isort_compatible.py:4:0: W0611: Unused get_module_part imported from astroid.modutils (unused-import)
isort_compatible.py:4:0: W0611: Unused is_standard_module imported from astroid.modutils (unused-import)
isort_compatible.py:3:0: C0412: Imports from package astroid are not grouped (ungrouped-imports)

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Your code has been rated at -7.50/10

$  ✘ pylint pylint_compatible.py 

************* Module pylint_compatible
pylint_compatible.py:1:0: W0611: Unused import isort (unused-import)
pylint_compatible.py:2:0: W0611: Unused import astroid (unused-import)
pylint_compatible.py:3:0: W0611: Unused are_exclusive imported from astroid (unused-import)
pylint_compatible.py:3:0: W0611: Unused decorators imported from astroid (unused-import)
pylint_compatible.py:4:0: W0611: Unused get_module_part imported from astroid.modutils (unused-import)
pylint_compatible.py:4:0: W0611: Unused is_standard_module imported from astroid.modutils (unused-import)

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Your code has been rated at -5.00/10

[PCManticore]

Thanks @Pierre-Sassoulas I can reproduce it as well with the latest isort. As mentioned, I'm in favour of first option.

[Pierre-Sassoulas]

This seems easier than refactoring the message store. Well a LOT easier.