changegroup: inline prune() logic from narrow prune() needs to ellide manifests that aren't part of the narrow matcher. The code is violating storage abstractions, so a comment has been added. Keep in mind the impetus for moving this code to core is so changegroup code can be refactored to be storage agnostic. Differential Revision: https://phab.mercurial-scm.org/D4012

fileset: extract language processing part to new module (API) I'll add a couple more functions that work on parsed tree. % wc -l mercurial/fileset*.py 559 mercurial/fileset.py 135 mercurial/filesetlang.py 694 total

fileset: flatten 'or' nodes to unnest unionmatchers This also makes it easier to compile a union of basic patterns into a single regexp pattern.