Fix get_wrapper_attr / set_wrapper_attr. (#1293)

Co-authored-by: Mark Towers <mark.m.towers@gmail.com>

gymnasium/core.py

@@ -432,18 +432,23 @@ class Wrapper(
             name: The variable name
             value: The new variable value
         """
-        sub_env = self.env
-        attr_set = False
+        sub_env = self
 
-        while attr_set is False and isinstance(sub_env, Wrapper):
+        # loop through all the wrappers, checking if it has the variable name then setting it
+        #   otherwise stripping the wrapper to check the next.
+        #   end when the core env is reached
+        while isinstance(sub_env, Wrapper):
             if hasattr(sub_env, name):
                 setattr(sub_env, name, value)
-                attr_set = True
-            else:
-                sub_env = sub_env.env
+                return
 
-        if attr_set is False:
+            sub_env = sub_env.env
+
+        # check if the base environment has the wrapper, otherwise, we set it on the top (this) wrapper
+        if hasattr(sub_env, name):
             setattr(sub_env, name, value)
+        else:
+            setattr(self, name, value)
 
     def __str__(self):
         """Returns the wrapper name and the :attr:`env` representation string."""

tests/test_core.py

@@ -215,6 +215,16 @@ def test_get_set_wrapper_attr():
         env.unwrapped._disable_render_order_enforcing
     assert env.get_wrapper_attr("_disable_render_order_enforcing") is True
 
+    # Test with top-most wrapper
+    env.MY_ATTRIBUTE_1 = True
+    assert env.get_wrapper_attr("MY_ATTRIBUTE_1") is True
+    env.set_wrapper_attr("MY_ATTRIBUTE_1", False)
+    assert env.get_wrapper_attr("MY_ATTRIBUTE_1") is False
+
+    # Test with non-existing attribute
+    env.set_wrapper_attr("MY_ATTRIBUTE_2", True)
+    assert getattr(env, "MY_ATTRIBUTE_2") is True
+
 
 class TestRandomSeeding:
     @staticmethod