Moving a file in the same directory result in status 'R'.

rietveld.py

Index: rietveld.py
diff --git a/rietveld.py b/rietveld.py
index 835f24c2a8a35d11257c8b0282848b83f2e86f88..cade5b0a3e1c2fd3abacb401fc328da61280ab7b 100644
--- a/rietveld.py
+++ b/rietveld.py
@@ -113,7 +113,7 @@ class Rietveld(object):
       # If not status, just assume it's a 'M'. Rietveld often gets it wrong and
       # just has status: null. Oh well.
       status = state.get('status') or 'M'
-      if status[0] not in ('A', 'D', 'M'):
+      if status[0] not in ('A', 'D', 'M', 'R'):
         raise patch.UnsupportedPatchFormat(
             filename, 'Change with status \'%s\' is not supported.' % status)