manifest: define and implement rev() on manifestlog Various code is accessing repo.manifestlog._revlog - a private attribute. This bypasses our interface and makes it difficult to implement non-revlog manifest storage. This commit adds a rev() method to the manifestlog interface and class and teaches callers to use it. Ideally this method wouldn't exist, as very few consumers should need to resolve the revision number of a manifest. Again, the primary goal of interface work is to establish and use interfaces first and to improve them later. Differential Revision: https://phab.mercurial-scm.org/D3882

--- a/mercurial/templatekw.py	Mon Jul 02 11:14:13 2018 -0700
+++ b/mercurial/templatekw.py	Wed Jul 04 12:12:49 2018 -0700
@@ -465,7 +465,7 @@
     if mnode is None:
         # just avoid crash, we might want to use the 'ff...' hash in future
         return
-    mrev = repo.manifestlog._revlog.rev(mnode)
+    mrev = repo.manifestlog.rev(mnode)
     mhex = hex(mnode)
     mapping = context.overlaymap(mapping, {'rev': mrev, 'node': mhex})
     f = context.process('manifest', mapping)