API: remove deep keyword from EA.copy

doc/source/whatsnew/v0.25.0.rst

@@ -804,6 +804,7 @@ ExtensionArray
 
 - Bug in :func:`factorize` when passing an ``ExtensionArray`` with a custom ``na_sentinel`` (:issue:`25696`).
 - :meth:`Series.count` miscounts NA values in ExtensionArrays (:issue:`26835`)
+- Keyword argument ``deep`` has been removed from :method:`ExtensionArray.copy` (:issue:`27083`)
 
 Other
 ^^^^^

pandas/core/arrays/base.py

@@ -820,15 +820,10 @@ def take(self, indices, allow_fill=False, fill_value=None):
         # pandas.api.extensions.take
         raise AbstractMethodError(self)
 
-    def copy(self, deep: bool = False) -> ABCExtensionArray:
+    def copy(self) -> ABCExtensionArray:
         """
         Return a copy of the array.
 
-        Parameters
-        ----------
-        deep : bool, default False
-            Also copy the underlying data backing this array.
-
         Returns
         -------
         ExtensionArray

pandas/core/arrays/datetimelike.py

@@ -605,7 +605,7 @@ def _concat_same_type(cls, to_concat):
         values = np.concatenate([x.asi8 for x in to_concat])
         return cls(values, dtype=dtype)
 
-    def copy(self, deep=False):
+    def copy(self):
         values = self.asi8.copy()
         return type(self)._simple_new(values, dtype=self.dtype, freq=self.freq)
 

pandas/core/arrays/integer.py

@@ -1,4 +1,3 @@
-import copy
 import sys
 from typing import Type
 import warnings
@@ -375,14 +374,10 @@ def take(self, indexer, allow_fill=False, fill_value=None):
 
         return type(self)(result, mask, copy=False)
 
-    def copy(self, deep=False):
+    def copy(self):
         data, mask = self._data, self._mask
-        if deep:
-            data = copy.deepcopy(data)
-            mask = copy.deepcopy(mask)
-        else:
-            data = data.copy()
-            mask = mask.copy()
+        data = data.copy()
+        mask = mask.copy()
         return type(self)(data, mask, copy=False)
 
     def __setitem__(self, key, value):

pandas/core/arrays/interval.py

@@ -680,21 +680,16 @@ def _shallow_copy(self, left=None, right=None, closed=None):
         return self._simple_new(
             left, right, closed=closed, verify_integrity=False)
 
-    def copy(self, deep=False):
+    def copy(self):
         """
         Return a copy of the array.
 
-        Parameters
-        ----------
-        deep : bool, default False
-            Also copy the underlying data backing this array.
-
         Returns
         -------
         IntervalArray
         """
-        left = self.left.copy(deep=True) if deep else self.left
-        right = self.right.copy(deep=True) if deep else self.right
+        left = self.left.copy(deep=True)
+        right = self.right.copy(deep=True)
         closed = self.closed
         # TODO: Could skip verify_integrity here.
         return type(self).from_arrays(left, right, closed=closed)

pandas/core/arrays/numpy_.py

@@ -285,7 +285,7 @@ def take(self, indices, allow_fill=False, fill_value=None):
                       fill_value=fill_value)
         return type(self)(result)
 
-    def copy(self, deep=False):
+    def copy(self):
         return type(self)(self._ndarray.copy())
 
     def _values_for_argsort(self):

pandas/core/arrays/sparse.py

@@ -1262,12 +1262,8 @@ def searchsorted(self, v, side="left", sorter=None):
             v, side, sorter
         )
 
-    def copy(self, deep=False):
-        if deep:
-            values = self.sp_values.copy()
-        else:
-            values = self.sp_values
-
+    def copy(self):
+        values = self.sp_values.copy()
         return self._simple_new(values, self.sp_index, self.dtype)
 
     @classmethod

pandas/core/indexes/interval.py

@@ -429,7 +429,9 @@ def __reduce__(self):
 
     @Appender(_index_shared_docs['copy'])
     def copy(self, deep=False, name=None):
-        array = self._data.copy(deep=deep)
+        array = self._data
+        if deep:
+            array = array.copy()
         attributes = self._get_attributes_dict()
         if name is not None:
             attributes.update(name=name)

pandas/core/internals/blocks.py

@@ -2212,7 +2212,7 @@ def copy(self, deep=True):
         """ copy constructor """
         values = self.values
         if deep:
-            values = values.copy(deep=True)
+            values = values.copy()
         return self.make_block_same_class(values)
 
     def get_values(self, dtype=None):

pandas/core/internals/construction.py

@@ -199,8 +199,10 @@ def init_dict(data, index, columns, dtype=None):
         arrays = (com.maybe_iterable_to_list(data[k]) for k in keys)
         # GH#24096 need copy to be deep for datetime64tz case
         # TODO: See if we can avoid these copies
+        arrays = [arr if not isinstance(arr, ABCIndexClass) else arr._data
+                  for arr in arrays]
         arrays = [arr if not is_datetime64tz_dtype(arr) else
-                  arr.copy(deep=True) for arr in arrays]
+                  arr.copy() for arr in arrays]
     return arrays_to_mgr(arrays, data_names, index, columns, dtype=dtype)
 
 

pandas/core/sparse/series.py

@@ -450,7 +450,9 @@ def copy(self, deep=True):
         """
         # TODO: https://github.com/pandas-dev/pandas/issues/22314
         # We skip the block manager till that is resolved.
-        new_data = self.values.copy(deep=deep)
+        new_data = self.values
+        if deep:
+            new_data = new_data.copy()
         return self._constructor(new_data, sparse_index=self.sp_index,
                                  fill_value=self.fill_value,
                                  index=self.index.copy(),

pandas/tests/arrays/sparse/test_array.py

@@ -591,9 +591,9 @@ def test_set_fill_invalid_non_scalar(self, val):
         with pytest.raises(ValueError, match=msg):
             arr.fill_value = val
 
-    def test_copy_shallow(self):
-        arr2 = self.arr.copy(deep=False)
-        assert arr2.sp_values is self.arr.sp_values
+    def test_copy(self):
+        arr2 = self.arr.copy()
+        assert arr2.sp_values is not self.arr.sp_values
         assert arr2.sp_index is self.arr.sp_index
 
     def test_values_asarray(self):

pandas/tests/extension/arrow/bool.py

@@ -108,11 +108,8 @@ def take(self, indices, allow_fill=False, fill_value=None):
                       allow_fill=allow_fill)
         return self._from_sequence(result, dtype=self.dtype)
 
-    def copy(self, deep=False):
-        if deep:
-            return type(self)(copy.deepcopy(self._data))
-        else:
-            return type(self)(copy.copy(self._data))
+    def copy(self):
+        return type(self)(copy.copy(self._data))
 
     @classmethod
     def _concat_same_type(cls, to_concat):

pandas/tests/extension/arrow/test_bool.py

@@ -17,8 +17,9 @@ def dtype():
 
 @pytest.fixture
 def data():
-    return ArrowBoolArray.from_scalars(np.random.randint(0, 2, size=100,
-                                                         dtype=bool))
+    values = np.random.randint(0, 2, size=100, dtype=bool)
+    values[1] = ~values[0]
+    return ArrowBoolArray.from_scalars(values)
 
 
 @pytest.fixture
@@ -36,7 +37,9 @@ def test_array_type_with_arg(self, data, dtype):
 
 
 class TestInterface(BaseArrowTests, base.BaseInterfaceTests):
-    pass
+    def test_copy(self, data):
+        # __setitem__ does not work, so we only have a smoke-test
+        data.copy()
 
 
 class TestConstructors(BaseArrowTests, base.BaseConstructorsTests):

pandas/tests/extension/base/interface.py

@@ -66,3 +66,11 @@ def test_isna_extension_array(self, data_missing):
             assert not na.all()
 
             assert na.dtype._is_boolean
+
+    def test_copy(self, data):
+        # GH#27083 removing deep keyword from EA.copy
+        assert data[0] != data[1]
+        result = data.copy()
+
+        data[1] = data[0]
+        assert result[1] != result[0]

pandas/tests/extension/conftest.py

@@ -16,7 +16,7 @@ def data():
     """Length-100 array for this type.
 
     * data[0] and data[1] should both be non missing
-    * data[0] and data[1] should not gbe equal
+    * data[0] and data[1] should not be equal
     """
     raise NotImplementedError
 

pandas/tests/extension/decimal/array.py

@@ -101,10 +101,8 @@ def take(self, indexer, allow_fill=False, fill_value=None):
                       allow_fill=allow_fill)
         return self._from_sequence(result)
 
-    def copy(self, deep=False):
-        if deep:
-            return type(self)(self._data.copy())
-        return type(self)(self)
+    def copy(self):
+        return type(self)(self._data.copy())
 
     def astype(self, dtype, copy=True):
         if isinstance(dtype, type(self.dtype)):

pandas/tests/extension/json/array.py

@@ -143,7 +143,7 @@ def take(self, indexer, allow_fill=False, fill_value=None):
 
         return self._from_sequence(output)
 
-    def copy(self, deep=False):
+    def copy(self):
         return type(self)(self.data[:])
 
     def astype(self, dtype, copy=True):

pandas/tests/extension/test_sparse.py

@@ -98,6 +98,10 @@ class TestInterface(BaseSparseTests, base.BaseInterfaceTests):
     def test_no_values_attribute(self, data):
         pytest.skip("We have values")
 
+    def test_copy(self, data):
+        # __setitem__ does not work, so we only have a smoke-test
+        data.copy()
+
 
 class TestConstructors(BaseSparseTests, base.BaseConstructorsTests):
     pass