copy: to find copy source, walk parent of revision we're marking copies in As shown in the previous patch, `hg cp --after --at-rev . src dst` fails if `src` is not in `.`. It seems obvious that you should always walk the *parent* of the revision you're marking copies in, but that's not how it was done for the working copy, and I didn't think to change it when marking copies in a non-working-copy commit. This patch fixes that by walking the parent commit instead, but only if we're marking copies for a non-working-copy commit. We need to leave the working-copy code unchanged because it depends on the weird behavior of `workingctx.walk()`. With these changes, there's very little overlap between the working-copy version and the non-working-copy version of `walkpats()`, but I've refrained from cleaning that up on the stable branch. Differential Revision: https://phab.mercurial-scm.org/D8494

tests: show that `hg cp -A --at-rev .` doesn't work for renames I clearly forgot to implement (and test) support for marking of renames when I added support for marking of copies :( Differential Revision: https://phab.mercurial-scm.org/D8493

formatting: add missing newline Differential Revision: https://phab.mercurial-scm.org/D8509

fastexport: downgrade message about already exported changesets to debug The old warning level is just too noisy for incremental processing. Differential Revision: https://phab.mercurial-scm.org/D8487

revisions: parse "x123" as "nodeid starting with 123" without prefixhexnode `experimental.revisions.prefixhexnode` makes it so the template function `shortest()` uses an "x" prefix to disambiguate between short nodeids and revnums. That config has so far also been used for enabling parsing of "x123" unambiguously as a nodeid. That makes it a little annoying for people who have prefixhexnode=yes to share such nodeids with people who have prefixhexnode=no ("x123" will be considered invalid for them). There seems to be little harm in allowing that parsing for everyone. We still let e.g. bookmark names like "x123" take precedence over the nodeid, so that's not a concern. The only thing I can think of is that people get used to the "x" prefix being valid, making it impossible for us to change to a different prefix if we wanted to do that when graduating the feature. Differential Revision: https://phab.mercurial-scm.org/D8514

status: use cmdutil.check_at_most_one_arg() for checking --rev/--change There are apparently no tests for this either. Differential Revision: https://phab.mercurial-scm.org/D8511

diff: use cmdutil.check_at_most_one_arg() for checking --rev/--change The same check was done in extdiff as well, so I fixed that too. There are apparently no tests for this. Differential Revision: https://phab.mercurial-scm.org/D8510