Better approach in 'unnecessary-list-index-lookup' to avoid crashes

[Pierre-Sassoulas]

Type of Changes

	Type
✓	🐛 Bug fix

Description

Got real tired of the crashes in enumerate when inferring the value of start following #7821, #7963, #8069, #8207, #9074, #9078, #9272, so inference most of the time it is.

Fixed crash in 'unnecessary-list-index-lookup' when starting an enumeration using
minus the length of an iterable inside a dict comprehension when the len call was only
made in this dict comprehension, and not elsewhere. Also changed the approach,
to use inference in all cases but the simple ones, so we don't have to fix crashes
one by one for arbitrarily complex expressions in enumerate.

Closes #10510

[Pierre-Sassoulas]

We also avoid this call when we have a const or minus a const so my intuition is that it's going to be faster in the common use case, even if we infer more on the strange use case, but I'm not in the mood for a benchmark to prove it.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.85%. Comparing base (a49e11a) to head (ca4f7b1).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10511      +/-   ##
==========================================
- Coverage   95.85%   95.85%   -0.01%     
==========================================
  Files         177      177              
  Lines       19285    19284       -1     
==========================================
- Hits        18486    18484       -2     
- Misses        799      800       +1     

Files with missing lines	Coverage Δ
pylint/checkers/refactoring/refactoring_checker.py	98.06% <100.00%> (-0.11%)	⬇️

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[github-actions]

🤖 According to the primer, this change has no effect on the checked open source code. 🤖🎉

This comment was generated for commit ca4f7b1

[Pierre-Sassoulas]

Suggested change

	inferred = utils.safe_infer(node)
	if isinstance(node, (nodes.Name, nodes.Call, nodes.Attribute)) or (
	isinstance(node, nodes.UnaryOp)
	and isinstance(node.operand, (nodes.Attribute, nodes.Name))
	):
	inferred = utils.safe_infer(node)

Alternatively...

[pylint-backport-bot]

The backport to maintenance/3.3.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-maintenance/3.3.x maintenance/3.3.x
# Navigate to the new working tree
cd .worktrees/backport-maintenance/3.3.x
# Create a new branch
git switch --create backport-10511-to-maintenance/3.3.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 a52dd5851604d72249b29b022f52b742a5730d61
# Push it to GitHub
git push --set-upstream origin backport-10511-to-maintenance/3.3.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-maintenance/3.3.x

Then, create a pull request where the base branch is maintenance/3.3.x and the compare/head branch is backport-10511-to-maintenance/3.3.x.