manifest: define and implement rev() on manifestlog
Various code is accessing repo.manifestlog._revlog - a private
attribute. This bypasses our interface and makes it difficult to
implement non-revlog manifest storage.
This commit adds a rev() method to the manifestlog interface and
class and teaches callers to use it.
Ideally this method wouldn't exist, as very few consumers should
need to resolve the revision number of a manifest. Again, the
primary goal of interface work is to establish and use interfaces
first and to improve them later.
Differential Revision: https://phab.mercurial-scm.org/D3882
https://bz.mercurial-scm.org/522
In the merge below, the file "foo" has the same contents in both
parents, but if we look at the file-level history, we'll notice that
the version in p1 is an ancestor of the version in p2. This test makes
sure that we'll use the version from p2 in the manifest of the merge
revision.
$ hg init
$ echo foo > foo
$ hg ci -qAm 'add foo'
$ echo bar >> foo
$ hg ci -m 'change foo'
$ hg backout -r tip -m 'backout changed foo'
reverting foo
changeset 2:4d9e78aaceee backs out changeset 1:b515023e500e
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ touch bar
$ hg ci -qAm 'add bar'
$ hg merge --debug
searching for copies back to rev 1
unmatched files in local:
bar
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: bbd179dfa0a7, local: 71766447bdbb+, remote: 4d9e78aaceee
foo: remote is newer -> g
getting foo
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg debugstate | grep foo
m 0 -2 unset foo
$ hg st -A foo
M foo
$ hg ci -m 'merge'
$ hg manifest --debug | grep foo
c6fc755d7e68f49f880599da29f15add41f42f5a 644 foo
$ hg debugindex foo
rev linkrev nodeid p1 p2
0 0 2ed2a3912a0b 000000000000 000000000000
1 1 6f4310b00b9a 2ed2a3912a0b 000000000000
2 2 c6fc755d7e68 6f4310b00b9a 000000000000