REF: rename PandasArray->NumpyExtensionArray (#54101)

* REF: rename PandasArray->NumpyExtensionArray

* document PandasDtype->NumpyEADtype

Author: jbrockmendel

ci/code_checks.sh

@@ -105,7 +105,7 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
         pandas.api.indexers.VariableOffsetWindowIndexer \
         pandas.api.extensions.ExtensionDtype \
         pandas.api.extensions.ExtensionArray \
-        pandas.arrays.PandasArray \
+        pandas.arrays.NumpyExtensionArray \
         pandas.api.extensions.ExtensionArray._accumulate \
         pandas.api.extensions.ExtensionArray._concat_same_type \
         pandas.api.extensions.ExtensionArray._formatter \

doc/source/development/contributing_codebase.rst

@@ -475,7 +475,7 @@ be located.
 
 8) Is your test for one of the pandas-provided ExtensionArrays (``Categorical``,
    ``DatetimeArray``, ``TimedeltaArray``, ``PeriodArray``, ``IntervalArray``,
-   ``PandasArray``, ``FloatArray``, ``BoolArray``, ``StringArray``)?
+   ``NumpyExtensionArray``, ``FloatArray``, ``BoolArray``, ``StringArray``)?
    This test likely belongs in one of:
 
    - tests.arrays

doc/source/reference/extensions.rst

@@ -24,7 +24,7 @@ objects.
    :template: autosummary/class_without_autosummary.rst
 
    api.extensions.ExtensionArray
-   arrays.PandasArray
+   arrays.NumpyExtensionArray
 
 .. We need this autosummary so that methods and attributes are generated.
 .. Separate block, since they aren't classes.

doc/source/whatsnew/v2.1.0.rst

@@ -286,6 +286,7 @@ See :ref:`install.dependencies` and :ref:`install.optional_dependencies` for mor
 
 Other API changes
 ^^^^^^^^^^^^^^^^^
+- :class:`arrays.PandasArray` has been renamed ``NumpyExtensionArray`` and the attached dtype name changed from ``PandasDtype`` to ``NumpyEADtype``; importing ``PandasArray`` still works until the next major version (:issue:`53694`)
 -
 
 .. ---------------------------------------------------------------------------

pandas/_testing/__init__.py

@@ -102,7 +102,7 @@
 from pandas.core.arrays import (
     BaseMaskedArray,
     ExtensionArray,
-    PandasArray,
+    NumpyExtensionArray,
 )
 from pandas.core.arrays._mixins import NDArrayBackedExtensionArray
 from pandas.core.construction import extract_array
@@ -307,7 +307,7 @@ def box_expected(expected, box_cls, transpose: bool = True):
     if box_cls is pd.array:
         if isinstance(expected, RangeIndex):
             # pd.array would return an IntegerArray
-            expected = PandasArray(np.asarray(expected._values))
+            expected = NumpyExtensionArray(np.asarray(expected._values))
         else:
             expected = pd.array(expected, copy=False)
     elif box_cls is Index:

pandas/_testing/asserters.py

@@ -25,7 +25,7 @@
     CategoricalDtype,
     DatetimeTZDtype,
     ExtensionDtype,
-    PandasDtype,
+    NumpyEADtype,
 )
 from pandas.core.dtypes.missing import array_equivalent
 
@@ -577,12 +577,12 @@ def raise_assert_detail(
 
     if isinstance(left, np.ndarray):
         left = pprint_thing(left)
-    elif isinstance(left, (CategoricalDtype, PandasDtype, StringDtype)):
+    elif isinstance(left, (CategoricalDtype, NumpyEADtype, StringDtype)):
         left = repr(left)
 
     if isinstance(right, np.ndarray):
         right = pprint_thing(right)
-    elif isinstance(right, (CategoricalDtype, PandasDtype, StringDtype)):
+    elif isinstance(right, (CategoricalDtype, NumpyEADtype, StringDtype)):
         right = repr(right)
 
     msg += f"""

pandas/arrays/__init__.py

@@ -12,7 +12,7 @@
     FloatingArray,
     IntegerArray,
     IntervalArray,
-    PandasArray,
+    NumpyExtensionArray,
     PeriodArray,
     SparseArray,
     StringArray,
@@ -28,9 +28,26 @@
     "FloatingArray",
     "IntegerArray",
     "IntervalArray",
-    "PandasArray",
+    "NumpyExtensionArray",
     "PeriodArray",
     "SparseArray",
     "StringArray",
     "TimedeltaArray",
 ]
+
+
+def __getattr__(name: str):
+    if name == "PandasArray":
+        # GH#53694
+        import warnings
+
+        from pandas.util._exceptions import find_stack_level
+
+        warnings.warn(
+            "PandasArray has been renamed NumpyExtensionArray. Use that "
+            "instead. This alias will be removed in a future version.",
+            FutureWarning,
+            stacklevel=find_stack_level(),
+        )
+        return NumpyExtensionArray
+    raise AttributeError(f"module 'pandas.arrays' has no attribute '{name}'")

pandas/core/algorithms.py

@@ -58,7 +58,7 @@
     BaseMaskedDtype,
     CategoricalDtype,
     ExtensionDtype,
-    PandasDtype,
+    NumpyEADtype,
 )
 from pandas.core.dtypes.generic import (
     ABCDatetimeArray,
@@ -1439,8 +1439,8 @@ def diff(arr, n: int, axis: AxisInt = 0):
     else:
         op = operator.sub
 
-    if isinstance(dtype, PandasDtype):
-        # PandasArray cannot necessarily hold shifted versions of itself.
+    if isinstance(dtype, NumpyEADtype):
+        # NumpyExtensionArray cannot necessarily hold shifted versions of itself.
         arr = arr.to_numpy()
         dtype = arr.dtype
 

pandas/core/arrays/__init__.py

@@ -11,7 +11,7 @@
 from pandas.core.arrays.integer import IntegerArray
 from pandas.core.arrays.interval import IntervalArray
 from pandas.core.arrays.masked import BaseMaskedArray
-from pandas.core.arrays.numpy_ import PandasArray
+from pandas.core.arrays.numpy_ import NumpyExtensionArray
 from pandas.core.arrays.period import (
     PeriodArray,
     period_array,
@@ -34,7 +34,7 @@
     "FloatingArray",
     "IntegerArray",
     "IntervalArray",
-    "PandasArray",
+    "NumpyExtensionArray",
     "PeriodArray",
     "period_array",
     "SparseArray",

pandas/core/arrays/_mixins.py

@@ -317,7 +317,8 @@ def fillna(self, value=None, method=None, limit: int | None = None) -> Self:
                 func(npvalues, limit=limit, mask=mask.T)
                 npvalues = npvalues.T
 
-                # TODO: PandasArray didn't used to copy, need tests for this
+                # TODO: NumpyExtensionArray didn't used to copy, need tests
+                #  for this
                 new_values = self._from_backing_data(npvalues)
             else:
                 # fill with value