Fix #5586: False positive for used-before-assignment with homonyms in filtered comprehensions and except blocks (#5666)

Co-authored-by: Pierre Sassoulas <[email protected]>

Author: jacobtylerwalls

ChangeLog

@@ -96,6 +96,12 @@ Release date: TBA
 
   Closes #5360, #3877
 
+* Fixed a false positive (affecting unreleased development) for
+  ``used-before-assignment`` involving homonyms between filtered comprehensions
+  and assignments in except blocks.
+
+  Closes #5586
+
 * Fixed crash with slots assignments and annotated assignments.
 
   Closes #5479

doc/whatsnew/2.13.rst

@@ -139,6 +139,12 @@ Other Changes
 
   Closes #5360, #3877
 
+* Fixed a false positive (affecting unreleased development) for
+  ``used-before-assignment`` involving homonyms between filtered comprehensions
+  and assignments in except blocks.
+
+  Closes #5586
+
 * Fixed crash on list comprehensions that used ``type`` as inner variable name.
 
   Closes #5461

pylint/checkers/variables.py

@@ -1316,6 +1316,13 @@ def _check_consumer(
             if utils.is_func_decorator(current_consumer.node) or not (
                 current_consumer.scope_type == "comprehension"
                 and self._has_homonym_in_upper_function_scope(node, consumer_level)
+                # But don't catch homonyms against the filter of a comprehension,
+                # (like "if x" in "[x for x in expr() if x]")
+                # https://github.com/PyCQA/pylint/issues/5586
+                and not (
+                    isinstance(node.parent.parent, nodes.Comprehension)
+                    and node.parent in node.parent.parent.ifs
+                )
             ):
                 self._check_late_binding_closure(node)
                 self._loopvar_name(node)

tests/functional/u/use/used_before_assignment_filtered_comprehension.py

@@ -0,0 +1,9 @@
+"""Homonym between filtered comprehension and assignment in except block."""
+
+def func():
+    """https://github.com/PyCQA/pylint/issues/5586"""
+    try:
+        print(value for value in range(1 / 0) if isinstance(value, int))
+    except ZeroDivisionError:
+        value = 1
+        print(value)