copies: extract an explicit `computechangesetcopie` method from context Right now, the logic around changeset centric copies data are buried into the "changectx" code. We extract this code in a dedicated method (in the copies module) for clarity. This clarity will help to explicitly compute and caches these data in the future.

config: fix fm.data() handling of defaultvalue This is a follow-up patch to rHG51a2e3102db2. This moves `fm.data()` out of the if block in `commands.config()`. Differential Revision: https://phab.mercurial-scm.org/D6720

config: remove pycompat.bytestr() for defaultvalue This is a follow-up patch to 51a2e3102db2. This removes `pycompat.bytestr` to preserve `None` in `commands.config()`. Differential Revision: https://phab.mercurial-scm.org/D6712

unshelve: clear shelvedstate and _finishunshelve() on partial unshelve On a partial unshelve, `shelvedstate` was not cleared and `_finishunshelve()` was not called. Ideally, these should be called on this case. This patch makes `shelvedstate` to delete after a successful partial unshelve and calls `_finishunshelve()` in the same case. Differential Revision: https://phab.mercurial-scm.org/D6708

unshelve: delete shelvedstate after a successful unshelve --continue `unshelve --continue` was preventing the deletion of `shelvedstate` on a partial `unshelve`. Ideally, `shelvedstate` should be deleted after a successful `unshelve`. Now, the behavior of `unshelve --continue` will be as follows in interactive mode: 1] The user tried to `unshelve` changes interactively but, ran into conflicts. 2] They resolved the conflicts and triggered `unshelve --continue` but, unshelved changes partially. 3] Now, on trying to do `unshelve --continue` again will abort as the last `unshelve` was successful and we are deleting the `shelvedstate`. 4] If they want to unshelve the remaining shelved change, they need to trigger `unshelve` without `--continue`. Differential Revision: https://phab.mercurial-scm.org/D6694

unshelve: handle stripping changesets on interactive mode On interactive mode, changesets on `nodestoremove` should be stripped regardless of the shelve is partial or not. This patch modifies `unshelvecontinue()` to do that. Differential Revision: https://phab.mercurial-scm.org/D6686

byteify-strings: add --version argument This is indispensable for automated tools to detect changes in behavior.

byteify-strings: add space in special comments to silence flake8 error This is done soon enough that nobody has had the time to use this feature yet.

revset: drop argument when it's None getstack's definition is `getstack(repo, rev=None)`, so providing None explicitly is unnecessary. Moreover, when x is not None, it's definitely not a revision but a part of a parsed tree of revset arguments. Differential Revision: https://phab.mercurial-scm.org/D6707

stack: remove unnecessary reverse() predicate Stack already sorts revisions, so no need to do it twice. This change was a part of D2400, which didn't land for other reasons. See also D2399, where this change was suggested. Differential Revision: https://phab.mercurial-scm.org/D6706