DEPR/REGR: Fix pandas.util.testing deprecation

pandas/tests/api/test_api.py

@@ -1,3 +1,4 @@
+import sys
 from typing import List
 
 import pandas as pd
@@ -288,14 +289,20 @@ def test_testing(self):
         self.check(testing, self.funcs)
 
     def test_util_testing_deprecated(self):
-        s = pd.Series([], dtype="object")
-        with tm.assert_produces_warning(FutureWarning) as m:
-            import pandas.util.testing as tm2
+        # avoid cache state affecting the test
+        sys.modules.pop("pandas.util.testing", None)
 
-            tm2.assert_series_equal(s, s)
+        with tm.assert_produces_warning(FutureWarning) as m:
+            import pandas.util.testing  # noqa: F401
 
-        assert "pandas.testing.assert_series_equal" in str(m[0].message)
+        assert "pandas.util.testing is deprecated" in str(m[0].message)
+        assert "pandas.testing instead" in str(m[0].message)
 
+    def test_util_testing_deprecated_direct(self):
+        # avoid cache state affecting the test
+        sys.modules.pop("pandas.util.testing", None)
         with tm.assert_produces_warning(FutureWarning) as m:
-            tm2.DataFrame
-        assert "removed" in str(m[0].message)
+            from pandas.util.testing import assert_series_equal  # noqa: F401
+
+        assert "pandas.util.testing is deprecated" in str(m[0].message)
+        assert "pandas.testing instead" in str(m[0].message)

pandas/util/__init__.py

@@ -1,4 +1,3 @@
 from pandas.util._decorators import Appender, Substitution, cache_readonly  # noqa
 
 from pandas.core.util.hashing import hash_array, hash_pandas_object  # noqa
-from pandas.util.testing import testing  # noqa: F401

pandas/util/testing.py

@@ -0,0 +1,12 @@
+import warnings
+
+from pandas._testing import *  # noqa
+
+warnings.warn(
+    (
+        "pandas.util.testing is deprecated. Use the functions in the "
+        "public API at pandas.testing instead."
+    ),
+    FutureWarning,
+    stacklevel=2,
+)