index: make "nt_*" functions work on an initialized nodetree I want to be able to reuse these functions with another nodetree instance later (for disambiguating node prefix within a revset). That other nodetree instance won't want to be fully populated from the index, so this commit moves that part to the callers. Differential Revision: https://phab.mercurial-scm.org/D4107

changegroup: inline _packellipsischangegroup It now does nothing special. The logic is simple enough to inline in the 2 callers in narrow that need it. The changegroup generation APIs could probably be a bit simpler. But that's for another time. Differential Revision: https://phab.mercurial-scm.org/D4092

changegroup: move fullnodes into cgpacker And with this change, the narrow packer no longer defines any addition attributes on packer instances! Differential Revision: https://phab.mercurial-scm.org/D4091

changegroup: specify ellipses mode explicitly Currently, code throughout changegroup relies on the presence of self._full_nodes to enable ellipses mode. This is a very tenuous check. And the check may be wrong once we move _full_nodes into cgpacker. Let's capture the enabling of ellipses mode explicitly as a constructor argument and as an instance variable. We could probably derive ellipses mode by presence of other variables. But for now, this explicit approach seems simplest since it is most compatible with existing code. Differential Revision: https://phab.mercurial-scm.org/D4090