Assert parent is not None

[nickdrozd]

Type of Changes

	Type
✓	🐛 Bug fix

Description

Fixes one Mypy error.

[codecov]

Codecov Report

Merging #2110 (3d599e9) into main (a8a8593) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2110   +/-   ##
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  Coverage   92.75%   92.75%           
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  Files          94       94           
  Lines       11004    11005    +1     
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+ Hits        10207    10208    +1     
  Misses        797      797           

Flag	Coverage Δ
linux	92.52% <100.00%> (+<0.01%)	⬆️
pypy	88.05% <100.00%> (+<0.01%)	⬆️
windows	92.31% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
astroid/nodes/node_classes.py	94.90% <100.00%> (+<0.01%)	⬆️

[DanielNoord]

I think we should think about making this some sort of generic attribute of NodeNG. There are lots of nodes where we know that parent is not None. Not having to put asserts everywhere would be much better, but I haven't had the time to look into how to do this properly.

[nickdrozd]

When is it possible for there to be no parent? Just for modules?

[nickdrozd]

As far as assertions go, I think it's worth adding them if it helps getting Mypy running without errors.

[DanielNoord]

When is it possible for there to be no parent? Just for modules?

I think so, but also for nodes that are constructed out of thin air. We do that quite often.

As far as assertions go, I think it's worth adding them if it helps getting Mypy running without errors.

I don't think so. Asserts change behaviour and can make pylint crash. We should only add them if we know they are true and can't find any other way to express what they are testing.

[jacobtylerwalls]

I think so, but also for nodes that are constructed out of thin air. We do that quite often.

The brains do this all over the place, see #1490 (comment).