fix: handle non-string dict keys holding lists in keylists/keypaths (#583)

Author: Sanjays2402

benedict/core/keylists.py

@@ -23,7 +23,10 @@ def _get_keylist_for_list(
     keylist = []
     for key, value in enumerate(ls):
         keys = list(parent_keys)
-        keys[-1] += f"[{key}]"
+        # Stringify the parent key before appending the index so non-string keys
+        # (e.g. int/None/bool) holding a list don't raise a TypeError. String keys
+        # are unaffected: f"{'a'}[0]" == "a[0]".
+        keys[-1] = f"{keys[-1]}[{key}]"
         keylist += [keys]
         keylist += _get_keylist_for_value(value, keys, indexes)
     return keylist

tests/core/test_keylists.py

@@ -60,6 +60,29 @@ def test_keylists_with_non_string_keys(self) -> None:
         for k in r:
             self.assertTrue(k in o)
 
+    def test_keylists_with_non_string_keys_and_lists_and_indexes_included(
+        self,
+    ) -> None:
+        # A non-string key (int/None/bool) holding a list used to raise
+        # 'TypeError: unsupported operand type(s) for +=: 'int' and 'str''
+        # while the same key holding a dict worked fine.
+        i = {
+            0: [1, 2],
+            None: [3, 4],
+        }
+        o = _keylists(i, indexes=True)
+        r = [
+            [0],
+            ["0[0]"],
+            ["0[1]"],
+            [None],
+            ["None[0]"],
+            ["None[1]"],
+        ]
+        self.assertEqual(len(o), len(r))
+        for k in r:
+            self.assertTrue(k in o)
+
     def test_keylists_with_lists_and_indexes_included(self) -> None:
         i = {
             "a": 1,