DEPR: Raise FutureWarning about raising an error in __array__ when copy=False cannot be honored

pandas/core/arrays/arrow/array.py

@@ -663,6 +663,16 @@ def __array__(
     ) -> np.ndarray:
         """Correctly construct numpy arrays when passed to `np.asarray()`."""
         if copy is False:
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             # TODO: By using `zero_copy_only` it may be possible to implement this
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."

pandas/core/arrays/categorical.py

@@ -1672,6 +1672,16 @@ def __array__(
         array(['a', 'b'], dtype=object)
         """
         if copy is False:
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False "
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )

pandas/core/arrays/datetimelike.py

@@ -359,6 +359,16 @@ def __array__(
         # used for Timedelta/DatetimeArray, overwritten by PeriodArray
         if is_object_dtype(dtype):
             if copy is False:
+                import warnings
+
+                from pandas.util._exceptions import find_stack_level
+
+                warnings.warn(
+                    "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                    "raise an error when a zero-copy numpy array is not possible",
+                    FutureWarning,
+                    stacklevel=find_stack_level(),
+                )
                 raise ValueError(
                     "Unable to avoid copy while creating an array as requested."
                 )

pandas/core/arrays/interval.py

@@ -1575,6 +1575,16 @@ def __array__(
         objects (with dtype='object')
         """
         if copy is False:
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )

pandas/core/arrays/masked.py

@@ -604,6 +604,17 @@ def __array__(
             if not self._hasna:
                 # special case, here we can simply return the underlying data
                 return np.array(self._data, dtype=dtype, copy=copy)
+
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )

pandas/core/arrays/period.py

@@ -415,6 +415,16 @@ def __array__(
                 return np.array(self.asi8, dtype=dtype)
 
         if copy is False:
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )

pandas/core/arrays/sparse/array.py

@@ -562,6 +562,16 @@ def __array__(
                 return self.sp_values
 
         if copy is False:
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )

pandas/core/generic.py

@@ -2152,6 +2152,16 @@ def __array__(
         if copy is False and not self._mgr.is_single_block and not self.empty:
             # check this manually, otherwise ._values will already return a copy
             # and np.array(values, copy=False) will not raise an error
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed the copy keyword behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible.",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )

pandas/core/indexes/multi.py

@@ -1314,6 +1314,16 @@ def __array__(self, dtype=None, copy=None) -> np.ndarray:
         """the array interface, return my values"""
         if copy is False:
             # self.values is always a newly construct array, so raise.
+            import warnings
+
+            from pandas.util._exceptions import find_stack_level
+
+            warnings.warn(
+                "Numpy>=2.0 changed copy keyword's behavior, making copy=False"
+                "raise an error when a zero-copy numpy array is not possible",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             raise ValueError(
                 "Unable to avoid copy while creating an array as requested."
             )