diff -r 5a7906ed78d4 -r 0c4b23ccf1a5 mercurial/configitems.py
--- a/mercurial/configitems.py	Fri Jan 12 10:14:20 2018 +0000
+++ b/mercurial/configitems.py	Fri Jan 12 10:41:03 2018 +0000
@@ -362,6 +362,9 @@
 coreconfigitem('devel', 'warn-config-unknown',
     default=None,
 )
+coreconfigitem('devel', 'debug.peer-request',
+    default=False,
+)
 coreconfigitem('diff', 'nodates',
     default=False,
 )