remove testing of sting dtype without storage specified.

Author: simonjayhawkins

pandas/conftest.py

@@ -1120,7 +1120,6 @@ def string_dtype(request):
 
 @pytest.fixture(
     params=[
-        "string",
         "string[python]",
         pytest.param(
             "string[pyarrow]", marks=td.skip_if_no("pyarrow", min_version="1.0.0")
@@ -1131,7 +1130,6 @@ def nullable_string_dtype(request):
     """
     Parametrized fixture for string dtypes.
 
-    * 'string'
     * 'string[python]'
     * 'string[pyarrow]'
     """
@@ -1179,7 +1177,6 @@ def object_dtype(request):
 @pytest.fixture(
     params=[
         "object",
-        "string",
         "string[python]",
         pytest.param(
             "string[pyarrow]", marks=td.skip_if_no("pyarrow", min_version="1.0.0")
@@ -1190,7 +1187,6 @@ def any_string_dtype(request):
     """
     Parametrized fixture for string dtypes.
     * 'object'
-    * 'string'
     * 'string[python]'
     * 'string[pyarrow]'
     """

pandas/tests/extension/base/casting.py

@@ -48,7 +48,6 @@ def test_astype_str(self, data):
     @pytest.mark.parametrize(
         "nullable_string_dtype",
         [
-            "string",
             "string[python]",
             pytest.param(
                 "string[pyarrow]", marks=td.skip_if_no("pyarrow", min_version="1.0.0")

pandas/tests/frame/methods/test_astype.py

@@ -584,7 +584,6 @@ def test_astype_empty_dtype_dict(self):
     @pytest.mark.parametrize(
         "data, dtype",
         [
-            (["x", "y", "z"], "string"),
             (["x", "y", "z"], "string[python]"),
             pytest.param(
                 ["x", "y", "z"],

pandas/tests/series/methods/test_astype.py

@@ -249,7 +249,6 @@ def test_td64_series_astype_object(self):
     @pytest.mark.parametrize(
         "data, dtype",
         [
-            (["x", "y", "z"], "string"),
             (["x", "y", "z"], "string[python]"),
             pytest.param(
                 ["x", "y", "z"],
@@ -387,7 +386,6 @@ def test_astype_string_to_extension_dtype_roundtrip(
                 reason="TODO StringArray.astype() with missing values #GH40566"
             )
             request.node.add_marker(mark)
-
         # GH-40351
         s = Series(data, dtype=dtype)
         result = s.astype(nullable_string_dtype).astype(dtype)

pandas/tests/series/methods/test_update.py

@@ -86,7 +86,6 @@ def test_update_from_non_series(self, series, other, expected):
     @pytest.mark.parametrize(
         "data, other, expected, dtype",
         [
-            (["a", None], [None, "b"], ["a", "b"], "string"),
             (["a", None], [None, "b"], ["a", "b"], "string[python]"),
             pytest.param(
                 ["a", None],