dirstate: move the _dirfoldmap to dirstatemap Now that dirstatemap is the source of truth for the list of directories, let's move _dirfoldmap on to it. This pattern of moving cached variables onto the dirstate map makes it easier to invalidate them, as seen by how the cache invalidation functions are slowly shrinking to just be recreating the dirstatemap instance. Differential Revision: https://phab.mercurial-scm.org/D983

--- a/contrib/perf.py	Thu Oct 05 11:34:41 2017 -0700
+++ b/contrib/perf.py	Thu Oct 05 11:34:41 2017 -0700
@@ -560,8 +560,8 @@
     dirstate = repo.dirstate
     'a' in dirstate
     def d():
-        dirstate._dirfoldmap.get('a')
-        del dirstate._dirfoldmap
+        dirstate._map.dirfoldmap.get('a')
+        del dirstate._map.dirfoldmap
         del dirstate._map.dirs
     timer(d)
     fm.end()