--- a/mercurial/commands.py Sun Feb 11 16:16:43 2018 -0800
+++ b/mercurial/commands.py Sun Feb 11 16:21:30 2018 -0800
@@ -1551,7 +1551,7 @@
extra = {}
if opts.get('close_branch'):
- extra['close'] = 1
+ extra['close'] = '1'
if not bheads:
raise error.Abort(_('can only close branch heads'))