Fix #5504: Fix crash if the output of items() is assigned to a 1-tuple (#5505)

* Fix #5504: Fix crash if the output of items() is assigned to a 1-tuple

Author: jacobtylerwalls

ChangeLog

@@ -25,6 +25,11 @@ Release date: TBA
 
   Closes #4716
 
+* Fix crash in ``unnecessary-dict-index-lookup`` checker if the output of
+  ``items()`` is assigned to a 1-tuple.
+
+  Closes #5504
+
 * The ``PyLinter`` class will now be initialiazed with a ``TextReporter``
   as its reporter if none is provided.
 

doc/whatsnew/2.13.rst

@@ -26,6 +26,11 @@ Other Changes
 
   Closes #4716
 
+* Fix crash in ``unnecessary-dict-index-lookup`` checker if the output of
+  ``items()`` is assigned to a 1-tuple.
+
+  Closes #5504
+
 * Fix false negative for ``consider-iterating-dictionary`` during membership checks encapsulated in iterables
   or ``not in`` checks
 

pylint/checkers/refactoring/refactoring_checker.py

@@ -1882,6 +1882,8 @@ def _check_unnecessary_dict_index_lookup(
                     if isinstance(value, nodes.Name):
                         if (
                             not isinstance(node.target, nodes.Tuple)
+                            # Ignore 1-tuples: for k, in d.items()
+                            or len(node.target.elts) < 2
                             or value.name != node.target.elts[0].name
                             or iterating_object_name != subscript.value.as_string()
                         ):

tests/functional/u/unnecessary/unnecessary_dict_index_lookup.py

@@ -100,3 +100,10 @@ class Foo:
     for key_two, val_two in val.items():
         del outer_dict[key][key_two]  # [unnecessary-dict-index-lookup]
         break
+
+# Test partial unpacking of items
+# https://github.com/PyCQA/pylint/issues/5504
+
+d = {}
+for key, in d.items():
+    print(d[key])