revset: add optional offset argument to limit() predicate
It's common for GUI or web frontend to fetch chunk of revisions per batch
size. Previously it was possible only if revisions were sorted by revision
number.
$ hg log -r 'limit({revspec} & :{last_known}, 101)'
So this patch introduces a general way to retrieve chunk of revisions after
skipping offset revisions.
$ hg log -r 'limit({revspec}, 100, {last_count})'
This is a dumb implementation. We can optimize it for baseset and spanset
later.
https://bz.mercurial-scm.org/1877
$ hg init a
$ cd a
$ echo a > a
$ hg add a
$ hg ci -m 'a'
$ echo b > a
$ hg ci -m'b'
$ hg up 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg book main
$ hg book
* main 0:cb9a9f314b8b
$ echo c > c
$ hg add c
$ hg ci -m'c'
created new head
$ hg book
* main 2:d36c0562f908
$ hg heads
changeset: 2:d36c0562f908
bookmark: main
tag: tip
parent: 0:cb9a9f314b8b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: c
changeset: 1:1e6c11564562
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ hg up 1e6c11564562
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark main)
$ hg merge main
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg book
main 2:d36c0562f908
$ hg ci -m'merge'
$ hg book
main 2:d36c0562f908
$ cd ..