fix: Unable to access nested list property

flask_restplus/fields.py

@@ -42,6 +42,10 @@ def is_indexable_but_not_string(obj):
     return not hasattr(obj, "strip") and hasattr(obj, "__iter__")
 
 
+def is_integer_indexable(obj):
+    return isinstance(obj, list) or isinstance(obj, tuple)
+
+
 def get_value(key, obj, default=None):
     '''Helper for pulling a keyed value off various types of objects'''
     if isinstance(key, int):
@@ -66,6 +70,11 @@ def _get_value_for_key(key, obj, default):
             return obj[key]
         except (IndexError, TypeError, KeyError):
             pass
+    if is_integer_indexable(obj):
+        try:
+            return obj[int(key)]
+        except (IndexError, TypeError, ValueError):
+            pass
     return getattr(obj, key, default)
 
 

tests/test_fields.py

@@ -1379,3 +1379,21 @@ def __getitem__(self, n):
 
         obj = Test('hi')
         assert fields.get_value('value', obj) == 'hi'
+
+    def test_get_value_int_indexable_list(self):
+        assert fields.get_value('bar.0', {'bar': [42]}) == 42
+
+    def test_get_value_int_indexable_list_with_str(self):
+        assert fields.get_value('bar.abc', {'bar': [42]}) == None
+
+    def test_get_value_int_indexable_nested_list(self):
+        assert fields.get_value('bar.0.val', {'bar': [{'val': 42}]}) == 42
+
+    def test_get_value_int_indexable_tuple_with_str(self):
+        assert fields.get_value('bar.abc', {'bar': (42, 43)}) == None
+
+    def test_get_value_int_indexable_tuple(self):
+        assert fields.get_value('bar.0', {'bar': (42, 43)}) == 42
+
+    def test_get_value_int_indexable_nested_tuple(self):
+        assert fields.get_value('bar.0.val', {'bar': [{'val': 42}]}) == 42