Fixed #22550 -- Prohibited QuerySet.last()/reverse() after slicing.

1 files changed, 12 insertions, 0 deletions

diff --git a/docs/releases/2.0.txt b/docs/releases/2.0.txt
index 39df2d891d..044123485d 100644
--- a/docs/releases/2.0.txt
+++ b/docs/releases/2.0.txt
@@ -314,6 +314,18 @@ If you wish to keep this restriction in the admin when editing users, set
     admin.site.unregister(User)
     admin.site.register(User, MyUserAdmin)
 
+``QuerySet.reverse()`` and ``last()`` are prohibited after slicing
+------------------------------------------------------------------
+
+Calling ``QuerySet.reverse()`` or ``last()`` on a sliced queryset leads to
+unexpected results due to the slice being applied after reordering. This is
+now prohibited, e.g.::
+
+    >>> Model.objects.all()[:2].reverse()
+    Traceback (most recent call last):
+    ...
+    TypeError: Cannot reverse a query once a slice has been taken.
+
 Miscellaneous
 -------------