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

rebase: move working parent and bookmark for obsoleted revs (BC) Previously, obsoleted revs with successors in destination are completely ignored. That caused some inconvenience when working copy is obsoleted. Most commands avoid working copy being obsoleted, but `hg pull` is an exception. This patch makes rebase able to move bookmarks or working parent for those obsoleted revs. It does so by keeping the obsoleted revs in `state` and marking them as "skipped, rebased to desired destination" during run-time. This reverts part of the behavior change of 3b7cb3d17137 and D24. Differential Revision: https://phab.mercurial-scm.org/D527

rebase: remove an unnecessary adjustdest in clearrebased `rev` being "skipped" could currently be caused by moving `rev` does not create a new commit. In this case, `state[rev]` is already changed to `p1`, and is a sane destination for bookmark or working parent movement. Therefore an additional destination adjustment is unnecessary. Differential Revision: https://phab.mercurial-scm.org/D565

rebase: sort destmap topologically Previously rebase source and destination could not overlap. But with the multi-destination support, source and destination could reasonably partially overlap. That requires another topological sort on `{sourcerev: destrev}` graph (destmap). This patch implements that. If a revision's destination is itself, the error message gets changed from "source is ancestor of destination" to "source and destination form a cycle". Not marking as BC since automation should depend on exit code, not error message. Differential Revision: https://phab.mercurial-scm.org/D470

rebase: initial support for multiple destinations This patch defines `SRC` (a single source revision) and `ALLSRC` (all source revisions) to be valid names in `--dest` revset if `--src` or `--rev` is used. So destination could be defined differently according to source revisions. The names are capitalized to make it clear they are "dynamically defined", distinguishable from normal revsets (Thanks Augie for the suggestion). This is useful, for example, `-r 'orphan()' -d 'calc-dest(SRC)'` to solve instability, which seems to be a highly wanted feature. The feature is not completed, namely if `-d` overlaps with `-r`, things could go wrong. A later patch will handle that case. The feature is also gated by `experimental.rebase.multidest` config option which is default off. Differential Revision: https://phab.mercurial-scm.org/D469

rebase: change internal format to support destination map A later patch will add multiple destination support. This patch changes internal state and the rebase state file format to support that. But the external interface still only supports single destination. A test was added to make sure rebase still supports legacy state file. The new state file is incompatible with old clients. We had done similar state file format change before: 5eac7ab, 92409f8, and 72412af. The state file is transient, so the impact of incompatibility is limited. Besides, the old client won't support multiple destinations anyway so it does not really make sense to make the file format compatible with them. Differential Revision: https://phab.mercurial-scm.org/D348

rebase: rewrite _computeobsoletenotrebased The old code stores successors of all related nodes together, which works fine if destination is unique. A future patch would make destination non-unique so let's change the implementation to test successors for rebaseset separately. Differential Revision: https://phab.mercurial-scm.org/D347