changegroup: remove _clnodetorev

cgpacker._clnodetorev is a glorified cache/index of changelog
nodes to revision numbers.

I'm not sure why it exists. Maybe performance? But its presence
is making refactoring of this code more complicated than it needs
to be.

This commit removes the cache and replaces it with direct lookups
against the changelog.

If this cache was for performance reasons, we should be able to
restore it easily enough... after the changegroup refactor is
complete.

Differential Revision: https://phab.mercurial-scm.org/D4189

mercurial/changegroup.py

@@ -533,7 +533,7 b' def _sortnodesnormal(store, nodes, reord'
     else:
         return sorted([store.rev(n) for n in nodes])
 
-def _sortnodesellipsis(store, nodes, clnodetorev, lookup):
+def _sortnodesellipsis(store, nodes, cl, lookup):
     """Sort nodes for changegroup generation and turn into revnums."""
     # Ellipses serving mode.
     #
@@ -551,7 +551,7 b' def _sortnodesellipsis(store, nodes, cln'
     # order that they're introduced in dramatis personae by the
     # changelog, so what we do is we sort the non-changelog histories
     # by the order in which they are used by the changelog.
-    key = lambda n: clnodetorev[lookup(n)]
+    key = lambda n: cl.rev(lookup(n))
     return [store.rev(n) for n in sorted(nodes, key=key)]
 
 def _revisiondeltanormal(store, rev, prev, linknode, deltaparentfn):
@@ -663,10 +663,6 b' class cgpacker(object):'
         self._clrevtolocalrev = {}
         self._nextclrevtolocalrev = {}
 
-        # Maps changelog nodes to changelog revs. Filled in once
-        # during changelog stage and then left unmodified.
-        self._clnodetorev = {}
-
     def _close(self):
         # Ellipses serving mode.
         self._clrevtolocalrev.clear()
@@ -695,6 +691,8 b' class cgpacker(object):'
             yield self._close()
             return
 
+        cl = self._repo.changelog
+
         # add the parent of the first rev
         p = store.parentrevs(revs[0])[0]
         revs.insert(0, p)
@@ -711,7 +709,7 b' class cgpacker(object):'
             linknode = lookup(store.node(curr))
 
             if self._ellipses:
-                linkrev = self._clnodetorev[linknode]
+                linkrev = cl.rev(linknode)
                 self._clrevtolocalrev[linkrev] = curr
 
                 # This is a node to send in full, because the changeset it
@@ -864,8 +862,6 b' class cgpacker(object):'
             clrevorder[x] = len(clrevorder)
 
             if self._ellipses:
-                self._clnodetorev[x] = cl.rev(x)
-
                 # Only update mfs if x is going to be sent. Otherwise we
                 # end up with bogus linkrevs specified for manifests and
                 # we skip some manifest nodes that we should otherwise
@@ -921,6 +917,7 b' class cgpacker(object):'
         change what is sent based in pulls vs pushes, etc.
         """
         repo = self._repo
+        cl = repo.changelog
         mfl = repo.manifestlog
         dirlog = mfl._revlog.dirlog
         tmfnodes = {'': mfs}
@@ -976,8 +973,8 b' class cgpacker(object):'
                 lookupfn = makelookupmflinknode(dir, nodes)
 
                 if self._ellipses:
-                    revs = _sortnodesellipsis(store, prunednodes,
-                                              self._clnodetorev, lookupfn)
+                    revs = _sortnodesellipsis(store, prunednodes, cl,
+                                              lookupfn)
                 else:
                     revs = _sortnodesnormal(store, prunednodes,
                                             self._reorder)
@@ -1025,6 +1022,7 b' class cgpacker(object):'
 
     def _generatefiles(self, changedfiles, linknodes, commonrevs, source):
         repo = self._repo
+        cl = repo.changelog
         progress = repo.ui.makeprogress(_('bundling'), unit=_('files'),
                                         total=len(changedfiles))
         for i, fname in enumerate(sorted(changedfiles)):
@@ -1043,7 +1041,7 b' class cgpacker(object):'
             if filenodes:
                 if self._ellipses:
                     revs = _sortnodesellipsis(filerevlog, filenodes,
-                                              self._clnodetorev, lookupfilelog)
+                                              cl, lookupfilelog)
                 else:
                     revs = _sortnodesnormal(filerevlog, filenodes,
                                             self._reorder)
@@ -1074,14 +1072,6 b' class cgpacker(object):'
                 return nullrev
 
             if ischangelog:
-                # If we're doing the changelog, it's possible that we
-                # have a parent that is already on the client, and we
-                # need to store some extra mapping information so that
-                # our contained ellipsis nodes will be able to resolve
-                # their parents.
-                if clrev not in self._clrevtolocalrev:
-                    clnode = store.node(clrev)
-                    self._clnodetorev[clnode] = clrev
                 return clrev
 
             # Walk the ellipsis-ized changelog breadth-first looking for a