dirstate-v2: Add `hg debugupgraderepo` command support
This command changes changes the file formats used inside an existing
repository to what they would be in a new repository with the current config.
For example:
hg debugupgraderepo --config format.exp-dirstate-v2=1 --run
hg debugupgraderepo --config format.exp-dirstate-v2=0 --run
If a repository has a dirstate in v1 format, the first command would upgrade it
to dirstate-v2. Conversely, if a repository has a dirstate in v2 format, the
second command would downgrade it to v1. (Both may also run some unrelated
upgrades.)
Since `format.exp-dirstate-v2` is currently disabled by default, not specifying
it in `--config` or any configuration file would result in the second command.
Differential Revision: https://phab.mercurial-scm.org/D10769
$ hg init repo
$ cd repo
$ echo 0 > a
$ hg ci -qAm 0
$ for i in 5 8 14 43 167; do
> hg up -q 0
> echo $i > a
> hg ci -qm $i
> done
$ cat <<EOF >> .hg/hgrc
> [alias]
> l = log -T '{rev}:{shortest(node,1)}\n'
> EOF
$ hg l
5:00f
4:7ba5d
3:7ba57
2:72
1:9
0:b
$ cat <<EOF >> .hg/hgrc
> [experimental]
> revisions.disambiguatewithin=not 4
> EOF
$ hg l
5:00
4:7ba5d
3:7b
2:72
1:9
0:b
9 was unambiguous and still is
$ hg l -r 9
1:9
7 was ambiguous and still is
$ hg l -r 7
abort: ambiguous revision identifier: 7
[10]
7b is no longer ambiguous
$ hg l -r 7b
3:7b
$ cd ..