--- a/contrib/perf.py	Mon Nov 26 00:08:11 2018 +0100
+++ b/contrib/perf.py	Mon Nov 26 00:13:50 2018 +0100
@@ -836,6 +836,7 @@
 
 @command(b'perfpathcopies', [], b"REV REV")
 def perfpathcopies(ui, repo, rev1, rev2, **opts):
+    """benchmark the copy tracing logic"""
     opts = _byteskwargs(opts)
     timer, fm = gettimer(ui, opts)
     ctx1 = scmutil.revsingle(repo, rev1, rev1)