rustfilepatterns: shorter code for concatenating slices Differential Revision: https://phab.mercurial-scm.org/D6765

match: simplify the regexps created for glob patterns For legibility of the resulting regexes, although it may help with performance as well. Differential Revision: https://phab.mercurial-scm.org/D6764

rustfilepatterns: refactor the pattern of removing a prefix from a &[u8] Differential Revision: https://phab.mercurial-scm.org/D6766

tests: show the pattern generated for a relative glob Differential Revision: https://phab.mercurial-scm.org/D6763

copies: remove existing copy info from the changeset on amend (BC) When amending a changeset with copy information in the changeset and the new changeset doesn't have any copy information (or similar for "filesadded" and "filesremoved"), we shouldn't keep it. A drawback of this is that we now unconditionally remove these four entries from the extras, breaking any extensions that happened to write entries with the same names (which seems very unlikely). I think I'd heard that there was list of blacklisted keys that would be removed from the extras when a commit is rewritten, but I couldn't find that. It would make sense to add the keys mentioned above there instead of the custom filtering I've added in this patch. Differential Revision: https://phab.mercurial-scm.org/D6752

tests: show invalid copies when turning off copies-in-changeset If you turn on copies in changesets and write a commit with a copy, then turn it off and amend the commit while undoing the copy, the invalid copy information will remain. The read path doesn't crash in invalid copy data, but it seems better to not produce the invalid data. Differential Revision: https://phab.mercurial-scm.org/D6751