REF: standardize ArrowExtensionArray in tests (#46009)

Author: jbrockmendel

pandas/tests/extension/arrow/arrays.py

@@ -77,7 +77,9 @@ class ArrowExtensionArray(OpsMixin, ExtensionArray):
     _data: pa.ChunkedArray
 
     @classmethod
-    def from_scalars(cls, values):
+    def _from_sequence(cls, values, dtype=None, copy=False):
+        # TODO: respect dtype, copy
+
         if isinstance(values, cls):
             # in particular for empty cases the pa.array(np.asarray(...))
             #  does not round-trip
@@ -91,15 +93,6 @@ def from_scalars(cls, values):
         arr = pa.chunked_array([pa.array(np.asarray(values))])
         return cls(arr)
 
-    @classmethod
-    def from_array(cls, arr):
-        assert isinstance(arr, pa.Array)
-        return cls(pa.chunked_array([arr]))
-
-    @classmethod
-    def _from_sequence(cls, scalars, dtype=None, copy=False):
-        return cls.from_scalars(scalars)
-
     def __repr__(self):
         return f"{type(self).__name__}({repr(self._data)})"
 
@@ -116,7 +109,7 @@ def __getitem__(self, item):
             return self._data.to_pandas()[item]
         else:
             vals = self._data.to_pandas()[item]
-            return type(self).from_scalars(vals)
+            return type(self)._from_sequence(vals)
 
     def __len__(self):
         return len(self._data)
@@ -160,7 +153,7 @@ def nbytes(self) -> int:
 
     def isna(self):
         nas = pd.isna(self._data.to_pandas())
-        return type(self).from_scalars(nas)
+        return type(self)._from_sequence(nas)
 
     def take(self, indices, allow_fill=False, fill_value=None):
         data = self._data.to_pandas()
@@ -182,7 +175,7 @@ def _concat_same_type(cls, to_concat):
         return cls(arr)
 
     def __invert__(self):
-        return type(self).from_scalars(~self._data.to_pandas())
+        return type(self)._from_sequence(~self._data.to_pandas())
 
     def _reduce(self, name: str, *, skipna: bool = True, **kwargs):
         if skipna:

pandas/tests/extension/arrow/test_bool.py

@@ -23,12 +23,12 @@ def dtype():
 def data():
     values = np.random.randint(0, 2, size=100, dtype=bool)
     values[1] = ~values[0]
-    return ArrowBoolArray.from_scalars(values)
+    return ArrowBoolArray._from_sequence(values)
 
 
 @pytest.fixture
 def data_missing():
-    return ArrowBoolArray.from_scalars([None, True])
+    return ArrowBoolArray._from_sequence([None, True])
 
 
 def test_basic_equals(data):

pandas/tests/extension/arrow/test_timestamp.py

@@ -51,10 +51,7 @@ def __init__(self, values):
 
 def test_constructor_extensionblock():
     # GH 34986
-    pd.DataFrame(
-        {
-            "timestamp": ArrowTimestampUSArray.from_scalars(
-                [None, datetime.datetime(2010, 9, 8, 7, 6, 5, 4)]
-            )
-        }
+    arr = ArrowTimestampUSArray._from_sequence(
+        [None, datetime.datetime(2010, 9, 8, 7, 6, 5, 4)]
     )
+    pd.DataFrame({"timestamp": arr})