only use c-contiguous

src/zarr/codecs/_v2.py

@@ -5,6 +5,7 @@
 from typing import TYPE_CHECKING
 
 import numcodecs
+import numpy as np
 from numcodecs.compat import ensure_ndarray_like
 
 from zarr.abc.codec import ArrayBytesCodec
@@ -19,10 +20,10 @@
 
 def ensure_contiguous(arr: NDArrayLike) -> NDArrayLike:
     flags = getattr(arr, "flags", None)
-    if flags is not None and (flags.c_contiguous or flags.f_contiguous):
+    if flags is not None and flags.c_contiguous:
         return arr
     else:
-        return arr.copy()
+        return np.ascontiguousarray(arr)
 
 
 @dataclass(frozen=True)

tests/test_v2.py

@@ -148,3 +148,11 @@ def test_v2_non_contiguous() -> None:
     arr[slice(6, 9, None), slice(3, 6, None)] = a[
         slice(6, 9, None), slice(3, 6, None)
     ]  # The slice on the RHS is important
+
+    a = np.ones((3, 3), order="F")
+    assert a.flags.f_contiguous
+    arr[slice(6, 9, None), slice(3, 6, None)] = a
+
+    a = np.ones((3, 3), order="C")
+    assert a.flags.c_contiguous
+    arr[slice(6, 9, None), slice(3, 6, None)] = a