diff --git a/mercurial/scmutil.py b/mercurial/scmutil.py
--- a/mercurial/scmutil.py
+++ b/mercurial/scmutil.py
@@ -1306,7 +1306,7 @@
     """
     return sink
 
-def unhidehashlikerevs(repo, specs, hiddentype):
+def unhidehashlikerevs(repo, specs, hiddentype, warnmessage=None):
     """parse the user specs and unhide changesets whose hash or revision number
     is passed.
 
@@ -1342,8 +1342,12 @@
     if hiddentype == 'warn':
         unfi = repo.unfiltered()
         revstr = ", ".join([pycompat.bytestr(unfi[l]) for l in revs])
-        repo.ui.warn(_("warning: accessing hidden changesets for write "
-                       "operation: %s\n") % revstr)
+        if warnmessage is None:
+            repo.ui.warn(_("warning: accessing hidden changesets for write "
+                           "operation: %s\n") % revstr)
+        else:
+            warnmessage += " %s\n"
+            repo.ui.warn(_(warnmessage) % revstr)
 
     # we have to use new filtername to separate branch/tags cache until we can
     # disbale these cache when revisions are dynamically pinned.