diff --git a/tests/functional/r/redefined/redefined_builtin_allowed.py b/tests/functional/r/redefined/redefined_builtin_allowed.py
index ec7697dfce..7574b5cb5f 100644
--- a/tests/functional/r/redefined/redefined_builtin_allowed.py
+++ b/tests/functional/r/redefined/redefined_builtin_allowed.py
@@ -7,3 +7,8 @@ def function():
     print(dir, dict)
 
 list = "not in globals" # [redefined-builtin]
+
+def global_variable_redefine():
+    """Shadow `len` using the `global` keyword."""
+    global len
+    len = 1  # [redefined-builtin]
diff --git a/tests/functional/r/redefined/redefined_builtin_allowed.rc b/tests/functional/r/redefined/redefined_builtin_allowed.rc
index 845729dcee..0a255bfae3 100644
--- a/tests/functional/r/redefined/redefined_builtin_allowed.rc
+++ b/tests/functional/r/redefined/redefined_builtin_allowed.rc
@@ -1,4 +1,4 @@
 [messages control]
-disable = invalid-name
+disable = invalid-name, global-variable-undefined
 [variables]
-allowed-redefined-builtins = dir, list
+allowed-redefined-builtins = dir, list, len
diff --git a/tests/functional/r/redefined/redefined_builtin_allowed.txt b/tests/functional/r/redefined/redefined_builtin_allowed.txt
index a0a049e2fd..669cb94bfc 100644
--- a/tests/functional/r/redefined/redefined_builtin_allowed.txt
+++ b/tests/functional/r/redefined/redefined_builtin_allowed.txt
@@ -1,2 +1,3 @@
 redefined-builtin:6:4:6:8:function:Redefining built-in 'dict':UNDEFINED
 redefined-builtin:9:0:9:4::Redefining built-in 'list':UNDEFINED
+redefined-builtin:14:4:14:7:global_variable_redefine:Redefining built-in 'len':UNDEFINED