revset: remove order information from tree (API) Keeping `order` in tree makes AST operation harder. And there could be invalid cases if trees could be generated and compounded freely, like: SetA(order=define) & SetB(order=define) ^^^^^^ couldn't be satisfied This patch changes the code to calculate order on the fly, during tree traversal. Optimization of reordering `and` arguments is preserved by introducing a new internal operation `flipand`. .. api:: revset.stringset() now takes 'order' as the last argument. Differential Revision: https://phab.mercurial-scm.org/D451

revset: drop optimization about reordering "or" set elements The reordering optimization is more important for "and" than "or", given the implementation details about "addset" and "filteredset" - reordering "or" may help "__contains__" test but not iteration, reordering "and" could help both. We are going to simplify the tree to remove ordering information. Removing "or" reordering optimization would make things simpler. This effectively reverts c63cb2d10d6d. It tracks back to the "orset" function added by the initial commit of revset (c9ce8ecd6). In the future, we might consider optimization at runtime (ex. do reordering and rewrites inside "orset"). Differential Revision: https://phab.mercurial-scm.org/D561

rebase: use _ctxdesc in one more place This simplifies the code. Differential Revision: https://phab.mercurial-scm.org/D566