protocol: use changegroupsubset() if possible (issue1389)

Due to the fix to the pull race, to avoid sending unnecessary
changesets, use changegroupsubset if possible.
This will increase the load on the server.

hgext/transplant.py

@@ -461,13 +461,16 b' def transplant(ui, repo, *revs, **opts):'
     def getremotechanges(repo, url):
         sourcerepo = ui.expandpath(url)
         source = hg.repository(ui, sourcerepo)
-        incoming = repo.findincoming(source, force=True)
+        common, incoming, rheads = repo.findcommonincoming(source, force=True)
         if not incoming:
             return (source, None, None)
 
         bundle = None
         if not source.local():
-            cg = source.changegroup(incoming, 'incoming')
+            if source.capable('changegroupsubset'):
+                cg = source.changegroupsubset(incoming, rheads, 'incoming')
+            else:
+                cg = source.changegroup(incoming, 'incoming')
             bundle = changegroup.writebundle(cg, None, 'HG10UN')
             source = bundlerepo.bundlerepository(ui, repo.root, bundle)
 

mercurial/commands.py

@@ -1700,7 +1700,8 b' def incoming(ui, repo, source="default",'
     ui.status(_('comparing with %s\n') % url.hidepassword(source))
     if revs:
         revs = [other.lookup(rev) for rev in revs]
-    incoming = repo.findincoming(other, heads=revs, force=opts["force"])
+    common, incoming, rheads = repo.findcommonincoming(other, heads=revs,
+                                                       force=opts["force"])
     if not incoming:
         try:
             os.unlink(opts["bundle"])
@@ -1714,6 +1715,10 b' def incoming(ui, repo, source="default",'
         fname = opts["bundle"]
         if fname or not other.local():
             # create a bundle (uncompressed if other repo is not local)
+
+            if revs is None and other.capable('changegroupsubset'):
+                revs = rheads
+
             if revs is None:
                 cg = other.changegroup(incoming, "incoming")
             else:

mercurial/localrepo.py

@@ -1266,6 +1266,22 b' class localrepository(repo.repository):'
         (and so we know that the rest of the nodes are missing in remote, see
         outgoing)
         """
+        return self.findcommonincoming(remote, base, heads, force)[1]
+
+    def findcommonincoming(self, remote, base=None, heads=None, force=False):
+        """Return a tuple (common, missing roots, heads) used to identify
+        missing nodes from remote.
+
+        If base dict is specified, assume that these nodes and their parents
+        exist on the remote side and that no child of a node of base exists
+        in both remote and self.
+        Furthermore base will be updated to include the nodes that exists
+        in self and remote but no children exists in self and remote.
+        If a list of heads is specified, return only nodes which are heads
+        or ancestors of these heads.
+
+        All the ancestors of base are in self and in remote.
+        """
         m = self.changelog.nodemap
         search = []
         fetch = {}
@@ -1280,8 +1296,8 b' class localrepository(repo.repository):'
         if self.changelog.tip() == nullid:
             base[nullid] = 1
             if heads != [nullid]:
-                return [nullid]
-            return []
+                return [nullid], [nullid], list(heads)
+            return [nullid], [], []
 
         # assume we're closer to the tip than the root
         # and start by examining the heads
@@ -1294,8 +1310,9 b' class localrepository(repo.repository):'
             else:
                 base[h] = 1
 
+        heads = unknown
         if not unknown:
-            return []
+            return base.keys(), [], []
 
         req = dict.fromkeys(unknown)
         reqcnt = 0
@@ -1390,7 +1407,7 b' class localrepository(repo.repository):'
 
         self.ui.debug(_("%d total queries\n") % reqcnt)
 
-        return fetch.keys()
+        return base.keys(), fetch.keys(), heads
 
     def findoutgoing(self, remote, base=None, heads=None, force=False):
         """Return list of nodes that are roots of subsets not in remote
@@ -1443,7 +1460,8 b' class localrepository(repo.repository):'
     def pull(self, remote, heads=None, force=False):
         lock = self.lock()
         try:
-            fetch = self.findincoming(remote, heads=heads, force=force)
+            common, fetch, rheads = self.findcommonincoming(remote, heads=heads,
+                                                            force=force)
             if fetch == [nullid]:
                 self.ui.status(_("requesting all changes\n"))
 
@@ -1451,10 +1469,13 b' class localrepository(repo.repository):'
                 self.ui.status(_("no changes found\n"))
                 return 0
 
+            if heads is None and remote.capable('changegroupsubset'):
+                heads = rheads
+
             if heads is None:
                 cg = remote.changegroup(fetch, 'pull')
             else:
-                if 'changegroupsubset' not in remote.capabilities:
+                if not remote.capable('changegroupsubset'):
                     raise util.Abort(_("Partial pull cannot be done because other repository doesn't support changegroupsubset."))
                 cg = remote.changegroupsubset(fetch, heads, 'pull')
             return self.addchangegroup(cg, 'pull', remote.url())

tests/test-fetch.out

@@ -100,7 +100,7 b' searching for changes'
 adding changesets
 adding manifests
 adding file changes
-added 1 changesets with 1 changes to 2 files
+added 1 changesets with 1 changes to 1 files
 % parent should be 2 (no automatic update)
 2
 

tests/test-http-proxy.out

@@ -62,13 +62,17 b' XXX "GET http://localhost:/?cmd=capabili'
 XXX "GET http://localhost:/?cmd=stream_out HTTP/1.1" - -
 XXX "GET http://localhost:/?pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000&cmd=between HTTP/1.1" - -
 XXX "GET http://localhost:/?cmd=heads HTTP/1.1" - -
-XXX "GET http://localhost:/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - -
+XXX "GET http://localhost:/?cmd=capabilities HTTP/1.1" - -
+XXX "GET http://localhost:/?bases=0000000000000000000000000000000000000000&cmd=changegroupsubset&heads=83180e7845de420a1bb46896fd5fe05294f8d629 HTTP/1.1" - -
 XXX "GET http://localhost:/?pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000&cmd=between HTTP/1.1" - -
 XXX "GET http://localhost:/?cmd=heads HTTP/1.1" - -
-XXX "GET http://localhost:/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - -
+XXX "GET http://localhost:/?cmd=capabilities HTTP/1.1" - -
+XXX "GET http://localhost:/?bases=0000000000000000000000000000000000000000&cmd=changegroupsubset&heads=83180e7845de420a1bb46896fd5fe05294f8d629 HTTP/1.1" - -
 XXX "GET http://localhost:/?pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000&cmd=between HTTP/1.1" - -
 XXX "GET http://localhost:/?cmd=heads HTTP/1.1" - -
-XXX "GET http://localhost:/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - -
+XXX "GET http://localhost:/?cmd=capabilities HTTP/1.1" - -
+XXX "GET http://localhost:/?bases=0000000000000000000000000000000000000000&cmd=changegroupsubset&heads=83180e7845de420a1bb46896fd5fe05294f8d629 HTTP/1.1" - -
 XXX "GET http://localhost:/?pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000&cmd=between HTTP/1.1" - -
 XXX "GET http://localhost:/?cmd=heads HTTP/1.1" - -
-XXX "GET http://localhost:/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - -
+XXX "GET http://localhost:/?cmd=capabilities HTTP/1.1" - -
+XXX "GET http://localhost:/?bases=0000000000000000000000000000000000000000&cmd=changegroupsubset&heads=83180e7845de420a1bb46896fd5fe05294f8d629 HTTP/1.1" - -