gh-91484: Address review comments

Author: jamie2779

Doc/library/stdtypes.rst

@@ -4876,8 +4876,9 @@ copying.
       Cast a memoryview to a new format or shape. *shape* defaults to
       ``[byte_length//new_itemsize]``, which means that the result view
       will be one-dimensional. The return value is a new memoryview, but
-      the buffer itself is not copied. Supported casts are 1D -> C-:term:`contiguous`
-      and C-contiguous -> 1D.
+      the buffer itself is not copied. Supported casts are
+      1D -> C-:term:`contiguous`, C-contiguous -> 1D, and
+      F-contiguous -> 1D.
 
       The destination format is restricted to a single element native format in
       :mod:`struct` syntax. One of the formats must be a byte format
@@ -4964,6 +4965,10 @@ copying.
       .. versionchanged:: 3.5
          The source format is no longer restricted when casting to a byte view.
 
+      .. versionchanged:: next
+         Casting a multi-dimensional F-contiguous view to a one-dimensional
+         view is now supported.
+
    .. method:: count(value, /)
 
       Count the number of occurrences of *value*.

Doc/whatsnew/3.16.rst

@@ -75,6 +75,10 @@ New features
 Other language changes
 ======================
 
+* :meth:`memoryview.cast` now allows casting a multidimensional
+  F-contiguous view to a one-dimensional view.
+  (Contributed by Jaemin Park in :gh:`91484`.)
+
 * :ref:`Frame objects <frame-objects>` now support :mod:`weak references
   <weakref>`.  This allows associating extra data with active frames,
   for example in debuggers, without keeping the frames (and everything

Misc/NEWS.d/next/Core_and_Builtins/2025-08-15-06-28-45.gh-issue-91484.huCgHt.rst

@@ -1 +1 @@
-memoryview.cast() now allows casting from N-D to 1-D for F-contiguous.
+:meth:`memoryview.cast` now allows casting from N-D to 1-D for F-contiguous.

Objects/memoryobject.c

@@ -1485,9 +1485,9 @@ memoryview_cast_impl(PyMemoryViewObject *self, PyObject *format,
     CHECK_RESTRICTED(self);
 
     if (!MV_C_CONTIGUOUS(self->flags)) {
-        if(shape || self->view.ndim == 1 || !MV_F_CONTIGUOUS(self->flags)) {
+        if (shape || !MV_F_CONTIGUOUS(self->flags)) {
             PyErr_SetString(PyExc_TypeError,
-                "memoryview: casts are restricted to C-contiguous views");
+                "memoryview: casts are restricted to contiguous views");
             return NULL;
         }
     }