Enh arrow json extension (#61103)

* WIP: Support PyArrow JSON type in ArrowDtype.type

* ENH: Added support for PyArrow JSON type in ArrowDtype.type

* ENH: Support PyArrow JSON type in ArrowDtype.type

Added support for PyArrow's JSON extension type in ArrowDtype.type by mapping JsonType to str. Fixes #60958.

* ENH: Support for PyArrow JSON type in ArrowDtype.type

Improved extension type handling by using BaseExtensionType for consistent storage type resolution across all PyArrow extension types, including JSON.

Fixes #60958

Author: asharmalik19

doc/source/whatsnew/v3.0.0.rst

@@ -61,6 +61,7 @@ Other enhancements
 - :meth:`Series.cummin` and :meth:`Series.cummax` now supports :class:`CategoricalDtype` (:issue:`52335`)
 - :meth:`Series.plot` now correctly handle the ``ylabel`` parameter for pie charts, allowing for explicit control over the y-axis label (:issue:`58239`)
 - :meth:`DataFrame.plot.scatter` argument ``c`` now accepts a column of strings, where rows with the same string are colored identically (:issue:`16827` and :issue:`16485`)
+- :class:`ArrowDtype` now supports ``pyarrow.JsonType`` (:issue:`60958`)
 - :class:`DataFrameGroupBy` and :class:`SeriesGroupBy` methods ``sum``, ``mean``, ``median``, ``prod``, ``min``, ``max``, ``std``, ``var`` and ``sem`` now accept ``skipna`` parameter (:issue:`15675`)
 - :class:`Rolling` and :class:`Expanding` now support ``nunique`` (:issue:`26958`)
 - :class:`Rolling` and :class:`Expanding` now support aggregations ``first`` and ``last`` (:issue:`33155`)

pandas/core/dtypes/dtypes.py

@@ -2265,7 +2265,7 @@ def type(self):
         elif pa.types.is_null(pa_type):
             # TODO: None? pd.NA? pa.null?
             return type(pa_type)
-        elif isinstance(pa_type, pa.ExtensionType):
+        elif isinstance(pa_type, pa.BaseExtensionType):
             return type(self)(pa_type.storage_type).type
         raise NotImplementedError(pa_type)
 

pandas/tests/extension/test_arrow.py

@@ -42,6 +42,7 @@
     pa_version_under11p0,
     pa_version_under13p0,
     pa_version_under14p0,
+    pa_version_under19p0,
     pa_version_under20p0,
 )
 
@@ -3553,3 +3554,13 @@ def test_categorical_from_arrow_dictionary():
         dtype="int64",
     )
     tm.assert_series_equal(result, expected)
+
+
+@pytest.mark.skipif(
+    pa_version_under19p0, reason="pa.json_ was introduced in pyarrow v19.0"
+)
+def test_arrow_json_type():
+    # GH 60958
+    dtype = ArrowDtype(pa.json_(pa.string()))
+    result = dtype.type
+    assert result == str