TST: Implement external error raised helper function. (pandas-dev#31130)

@gfyoung wrote this function here
pandas-dev#30999 (comment)
so we can ignore error messages without breaking fututre CI tests of
bare pytest raises calls

Co-authored-by: gfyoung <gfyoung17+GitHub@gmail.com>

xref pandas-devgh-30999

pandas/_testing.py

@@ -8,7 +8,7 @@
 from shutil import rmtree
 import string
 import tempfile
-from typing import Any, List, Optional, Union, cast
+from typing import Any, Callable, List, Optional, Type, Union, cast
 import warnings
 import zipfile
 
@@ -2757,3 +2757,24 @@ def convert_rows_list_to_csv_str(rows_list: List[str]):
     sep = os.linesep
     expected = sep.join(rows_list) + sep
     return expected
+
+
+def external_error_raised(
+    expected_exception: Type[Exception],
+) -> Callable[[Type[Exception], None], None]:
+    """
+    Helper function to mark pytest.raises that have an external error message.
+
+    Parameters
+    ----------
+    expected_exception : Exception
+        Expected error to raise.
+
+    Returns
+    -------
+    Callable
+        Regular `pytest.raises` function with `match` equal to `None`.
+    """
+    import pytest
+
+    return pytest.raises(expected_exception, match=None)

pandas/tests/util/test_util.py

@@ -76,3 +76,8 @@ def test_rng_context():
         with tm.RNGContext(1):
             assert np.random.randn() == expected1
         assert np.random.randn() == expected0
+
+
+def test_external_error_raised():
+    with tm.external_error_raised(TypeError):
+        raise TypeError("Should not check this error message, so it will pass")