# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 2014-10-09 11:12:20
# Node ID a1a02b516cca2d2df4f082fa977d56b1ca177865
# Parent  9e5576f822ccd2d21cae046b664c68bbeb667e6c

baseset: empty or one-element sets are ascending and descending

The empty set is full of interesting properties. In the ordering case, the one
element set is too.

diff --git a/mercurial/revset.py b/mercurial/revset.py
--- a/mercurial/revset.py
+++ b/mercurial/revset.py
@@ -2368,12 +2368,16 @@ class baseset(abstractsmartset):
         """Returns True if the collection is ascending order, False if not.
 
         This is part of the mandatory API for smartset."""
+        if len(self) <= 1:
+            return True
         return self._ascending is not None and self._ascending
 
     def isdescending(self):
         """Returns True if the collection is descending order, False if not.
 
         This is part of the mandatory API for smartset."""
+        if len(self) <= 1:
+            return True
         return self._ascending is not None and not self._ascending
 
     def first(self):