FIX: adapt handling of copy keyword argument in scipy backend for numpy >= 2.0dev (#8851)

* FIX: adapt handling of copy keyword argument in scipy backend for numpy >= 2.0dev

FIX: adapt handling of copy keyword argument in scipy backend for numpy >= 2.0dev

* Add whats-new.rst entry

* Apply suggestions from code review

---------

Co-authored-by: Deepak Cherian <[email protected]>

Author: kmuehlbauer

doc/whats-new.rst

@@ -59,6 +59,8 @@ Bug fixes
   By `Kai Mühlbauer <https://github.com/kmuehlbauer>`_.
 - do not cast `_FillValue`/`missing_value` in `CFMaskCoder` if `_Unsigned` is provided
   (:issue:`8844`, :pull:`8852`).
+- Adapt handling of copy keyword argument in scipy backend for numpy >= 2.0dev
+  (:issue:`8844`, :pull:`8851`).
   By `Kai Mühlbauer <https://github.com/kmuehlbauer>`_.
 
 Documentation

xarray/backends/scipy_.py

@@ -28,6 +28,7 @@
     Frozen,
     FrozenDict,
     close_on_error,
+    module_available,
     try_read_magic_number_from_file_or_path,
 )
 from xarray.core.variable import Variable
@@ -39,6 +40,9 @@
     from xarray.core.dataset import Dataset
 
 
+HAS_NUMPY_2_0 = module_available("numpy", minversion="2.0.0.dev0")
+
+
 def _decode_string(s):
     if isinstance(s, bytes):
         return s.decode("utf-8", "replace")
@@ -76,6 +80,12 @@ def __getitem__(self, key):
         # with the netCDF4 library by ensuring we can safely read arrays even
         # after closing associated files.
         copy = self.datastore.ds.use_mmap
+
+        # adapt handling of copy-kwarg to numpy 2.0
+        # see https://github.com/numpy/numpy/issues/25916
+        # and https://github.com/numpy/numpy/pull/25922
+        copy = None if HAS_NUMPY_2_0 and copy is False else copy
+
         return np.array(data, dtype=self.dtype, copy=copy)
 
     def __setitem__(self, key, value):