destutil: remove redundant examination Before this patch, "len(heads) != len(otherheads)" is examined to detect whether message should be displayed or not. But if "repo.revs('%ln and parents()', heads)", heads should contain "parents()" and otherheads is always less than heads.

destutil: add new local variable to increase readability Before this patch, local variable 'heads' is used not only for "all branch heads" but also for "branch heads other than current parent". This patch newly adds local variable 'otherheads' for the latter purpose, to increase readability.

changegroup: write root manifests and subdir manifests in a single loop This is another step towards making the manifest generation recurse along the directory trees. The loop over 'tmfnodes' now takes the form of a queue. At this point, we only add to the queue twice: we add the root manifests, and, while visiting the root manifest revisions, we add all subdirectory revisions (for treemanifest repos). Thus, any iterations over 'tmfnodes' after the first will not add any items and the "queue" will just keep shrinking.

changegroup: introduce makelookupmflinknode(dir) This is another step towards making the manifest generation recurse along the directory trees. It makes the two calls to _packmanifests() more similar.

changegroup: prune subdirectory dirlogs too We already prune changesets, root manifests and files whose linkrev is in the set of common revisions. We should do the same for dirlogs.

changegroup: include subdirectory manifests in verbose size When verbose logging is one, we report the size in bytes of the manifest data in the changegroup. For files, we report the size per file, but I'm not sure we need that level of detail (i.e. size per directory manifest). Instead, report a single figure for the size of root manifest plus submanifests.

changegroup: make _packmanifests() dumber The next few patches will rewrite the manifest generation code to work with merges. We will then walk dirlogs recursively. This prepares for that by moving much of the treemanifest code out of _packmanifests() and into generatemanifests(). For this to work, it also adds _manifestsdone() method that returns the "end of manifests" close chunk for cg3 and an empty string for cg1 and cg2.

changegroup: extract generatemanifests() The changegroup.generate() function is pretty long, so let's extract the manifest generation part of it.