--- a/mercurial/cmdutil.py	Tue Dec 17 21:25:54 2019 -0500
+++ b/mercurial/cmdutil.py	Fri Dec 13 14:49:48 2019 -0800
@@ -268,6 +268,7 @@
     previous = None
     for x in args:
         if opts.get(x):
+            x = x.replace(b'_', b'-')
             if previous:
                 raise error.Abort(
                     _(b'cannot specify both --%s and --%s') % (previous, x)