changegroup: inline _packmanifests() into generatemanifests() It is relatively small. Every other generate*() calls group() directly. So the new code is consistent. Differential Revision: https://phab.mercurial-scm.org/D4198

changegroup: invert conditional and dedent I don't like seeing code that visually resembles the pyramid of doom. Differential Revision: https://phab.mercurial-scm.org/D4197

changegroup: make _revisiondeltanarrow() a standalone function It doesn't require any state on the packer. Everything impacting behavior is passed in as a function. So split it out, just like what was done for _revisiondeltanormal(). Differential Revision: https://phab.mercurial-scm.org/D4196

changegroup: pass state into _revisiondeltanarrow After this, the method no longer accesses self and can be split into a standalone function. Differential Revision: https://phab.mercurial-scm.org/D4195

changegroup: inline _close() Now that it doesn't clear self._clrevtolocalrev on every invocation and is a simple one-liner that calls another function, we can do away with this method and inline its content into all call sites. Differential Revision: https://phab.mercurial-scm.org/D4194

changegroup: pass clrevtolocalrev to each group clrevtolocalrev is a per-changegroup group mapping revisions to aid with shallow clone. Back when this functionality was implemented in an extension, this dict was added to the packer instance so monkeypatched functions could reference it there. Now that this code is part of core, we can pass the dict to each consumer properly so it doesn't have to live on the cgpacker instance. This commit does that. Differential Revision: https://phab.mercurial-scm.org/D4193

changegroup: combine _generatefiles() into generatefiles() These were split out in a06aab274aef as part of moving the narrow code into core. They don't need to be separate functions. Differential Revision: https://phab.mercurial-scm.org/D4192

changegroup: define linknodes callbacks in generatefiles() This is how it is done everywhere else. But the logic here is a bit more complex because shallow clone needs to reference the original linknode implementation. But at least now all function implementations are defined in the same place. Differential Revision: https://phab.mercurial-scm.org/D4191

changegroup: track changelog to manifest revision map explicitly Previously, self._nextclrevtolocalrev was only populated as part of the changelog lookup callback. But cgpacker._close() was looking at self._nextclrevtolocalrev on every invocation. Since self._nextclrevtolocalrev is for communicating the mapping of changelog revisions to manifest revisions, this commit refactors the code to make that explicit. The changelog state now stores this mapping. And after the changelog group is emitted, we update self._clrevtolocalrev with that dict. self._nextclrevtolocalrev is unused and has been deleted. Differential Revision: https://phab.mercurial-scm.org/D4190

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