merge: avoid superfluous filemerges when grafting through renames (issue5407) This is a fix for a regression introduced by the patches for issue4028. The test changes are due to us doing fewer _checkcopies searches now, which makes some test outputs revert to the pre-issue4028 behavior. That issue itself remains fixed, we only skip copy tracing for files where it isn't relevant. As a nice side effect, this makes copy detection much faster when tracing backwards through lots of renames.

--- a/tests/test-up-local-change.t	Wed Oct 19 18:06:14 2016 +0200
+++ b/tests/test-up-local-change.t	Tue Oct 25 21:01:53 2016 +0200
@@ -242,4 +242,11 @@
   -a
   +b
 
+test for superfluous filemerge of clean files renamed in the past
+
+  $ hg up -qC tip
+  $ echo c > c
+  $ hg add c
+  $ hg up -qt:fail 0
+
   $ cd ..