diff --git a/sklearn/compose/tests/test_column_transformer.py b/sklearn/compose/tests/test_column_transformer.py
index d26f6895427bb..ca1c185c91e06 100644
--- a/sklearn/compose/tests/test_column_transformer.py
+++ b/sklearn/compose/tests/test_column_transformer.py
@@ -1040,7 +1040,7 @@ def test_column_transformer_no_estimators_set_params():
 
 
 def test_column_transformer_callable_specifier():
-    # assert that function gets the full array / dataframe
+    # assert that function gets the full array
     X_array = np.array([[0, 1, 2], [2, 4, 6]]).T
     X_res_first = np.array([[0, 1, 2]]).T
 
@@ -1055,7 +1055,13 @@ def func(X):
     assert callable(ct.transformers[0][2])
     assert ct.transformers_[0][2] == [0]
 
+
+def test_column_transformer_callable_specifier_dataframe():
+    # assert that function gets the full dataframe
     pd = pytest.importorskip('pandas')
+    X_array = np.array([[0, 1, 2], [2, 4, 6]]).T
+    X_res_first = np.array([[0, 1, 2]]).T
+
     X_df = pd.DataFrame(X_array, columns=['first', 'second'])
 
     def func(X):