--- a/mercurial/fancyopts.py Fri Mar 06 10:52:44 2020 +0100
+++ b/mercurial/fancyopts.py Fri Mar 06 13:27:41 2020 -0500
@@ -314,7 +314,7 @@
argmap = {}
defmap = {}
negations = {}
- alllong = set(o[1] for o in options)
+ alllong = {o[1] for o in options}
for option in options:
if len(option) == 5: