Fix crash in unnecessary-list-index-lookup checker (pylint-dev#6049)

timmartin · Mar 30, 2022 · a40cae9 · a40cae9
1 parent 789a381
commit a40cae9
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diff --git a/pylint/checkers/refactoring/refactoring_checker.py b/pylint/checkers/refactoring/refactoring_checker.py
@@ -1994,6 +1994,11 @@ def _check_unnecessary_list_index_lookup(
             # enumerate() result is being assigned without destructuring
             return
 
+        if not isinstance(node.target.elts[1], nodes.AssignName):
+            # The value is not being assigned to a single variable, e.g. being
+            # destructured, so we can't necessarily use it.
+            return
+
         iterating_object_name = node.iter.args[0].name
         value_variable = node.target.elts[1]
 

diff --git a/tests/functional/u/unnecessary/unnecessary_list_index_lookup.py b/tests/functional/u/unnecessary/unnecessary_list_index_lookup.py
@@ -44,3 +44,8 @@ def process_list_again(data):
 result = [val for idx, val in enumerate(my_list) if idx > 0 and my_list[idx - 1] == 'a']
 result = [val for idx, val in enumerate(my_list) if other_list[idx] == 'a']
 result = [my_list[idx] for idx, val in enumerate(my_list)] # [unnecessary-list-index-lookup]
+
+# Issue #6409
+pairs = [(0, 0)]
+for i, (a, b) in enumerate(pairs):
+    print(pairs[i][0])