diff -r b45f4c1532c0 -r 6e526b0961a8 mercurial/extensions.py
--- a/mercurial/extensions.py	Thu May 03 18:15:43 2018 +0900
+++ b/mercurial/extensions.py	Thu May 03 18:22:02 2018 +0900
@@ -675,11 +675,12 @@
             break
     else:
         cmd = aliases[0]
-    return (cmd, name, mod)
+    doc = gettext(pycompat.getdoc(mod))
+    return (cmd, name, doc)
 
 def disabledcmd(ui, cmd, strict=False):
     '''import disabled extensions until cmd is found.
-    returns (cmdname, extname, module)'''
+    returns (cmdname, extname, doc)'''
 
     paths = _disabledpaths(strip_init=True)
     if not paths: