cmdstate: introduce a "saver" contextmanager and use it in place of save()
Previously, the state was only saved in some paths out of these functions. This
can be problematic, if the user ctrl-c's (or `kill -9`'s) the process, or we
exit out of `relocate` for anything besides the "expected" reason, we won't
record that we were in the middle of an evolve.
One of our users has discovered that this leaves hg in a weird state; the user
did something like this:
```
$ hg evolve
<something goes wrong with the merge tool, hits ctrl-c>
<deals with the merge conflicts>
$ hg evolve --continue
abort: no interrupted evolve to continue
$ hg evolve
abort: uncommitted changes
# Note: commands.status.verbose=True is set.
$ hg status
M foo
# The repository is in an unfinished *update* state.
# No unresolved merge conflicts
# To continue: hg update
```
The user did an `hg update`, but it didn't actually do anything besides take it
out of the unfinished update state (the files were still dirty in the working
directory).
$ cat >> $HGRCPATH <<EOF
> [web]
> push_ssl = false
> allow_push = *
> [phases]
> publish=False
> [alias]
> odiff=diff --rev 'limit(obsparents(.),1)' --rev .
> [extensions]
> EOF
$ mkcommit() {
> echo "$1" > "$1"
> hg add "$1"
> hg ci -m "add $1"
> }
create commit
$ hg init repo
$ cd repo
$ mkcommit a
$ mkcommit b
$ hg up -q 0
$ mkcommit c
created new head
forge old style relation files
$ hg log -r 2 --template='{node} ' > .hg/obsolete-relations
$ hg log -r 1 --template='{node}' >> .hg/obsolete-relations
enable the extensions
$ echo "obsolete=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/legacy.py" >> $HGRCPATH
$ hg log -G
abort: old format of obsolete marker detected!
run `hg debugconvertobsolete` once.
[255]
$ hg debugconvertobsolete --traceback
1 obsolete marker converted
$ hg log -G
@ changeset: 2:d67cd0334eee
| tag: tip
| parent: 0:1f0dee641bb7
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: add c
|
o changeset: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a
$ hg debugobsolete
7c3bad9141dcb46ff89abf5f61856facd56e476c d67cd0334eeecfded222fed9009f0db4beb57585 0 (*) {'user': 'test'} (glob)
$ hg debugconvertobsolete
nothing to do
0 obsolete marker converted
Convert json
$ cat > .hg/store/obsoletemarkers << EOF
> [
> {
> "reason": "import from older format.",
> "subjects": [
> "3218406b50ed13480765e7c260669620f37fba6e"
> ],
> "user": "Pierre-Yves David <pierre-yves.david@ens-lyon.org>",
> "date": [
> 1336503323.9768269,
> -7200
> ],
> "object": "3e03d82708d4da97a92158558dd13386d8f09ad5",
> "id": "4743f676eaf3923cb98c921ee06b2e91052c365b"
> },
> {
> "reason": "import from older format.",
> "user": "Pierre-Yves David <pierre-yves.david@logilab.fr>",
> "date": [
> 1336557472.7875929,
> -7200
> ],
> "object": "5c722672795c3a2cb94d0cc9a821c394c1475f87",
> "id": "1fd90a84b7225d2e3062b7e1b3100aa2e060fc72"
> },
> {
> "reason": "import from older format.",
> "subjects": [
> "0000000000000000000000000000000000000000"
> ],
> "user": "Pierre-Yves David <pierre-yves.david@logilab.fr>",
> "date": [
> 1336557472.784307,
> -7200
> ],
> "object": "2c3784e102bb34ccc93862af5bd6d609ee30c577",
> "id": "7d940c5ee1f886c8a6c0d805b43e522cb3ef7a15"
> }
> ]
> EOF
$ hg log -G
abort: old format of obsolete marker detected!
run `hg debugconvertobsolete` once.
[255]
$ hg debugconvertobsolete --traceback
3 obsolete marker converted
$ hg debugobsolete
7c3bad9141dcb46ff89abf5f61856facd56e476c d67cd0334eeecfded222fed9009f0db4beb57585 0 (*) {'user': 'test'} (glob)
3e03d82708d4da97a92158558dd13386d8f09ad5 3218406b50ed13480765e7c260669620f37fba6e 0 (Tue May 08 20:55:23 2012 +0200) {'user': 'Pierre-Yves David <pierre-yves.david@ens-lyon.org>'}
5c722672795c3a2cb94d0cc9a821c394c1475f87 0 (Wed May 09 11:57:52 2012 +0200) {'user': 'Pierre-Yves David <pierre-yves.david@logilab.fr>'}
2c3784e102bb34ccc93862af5bd6d609ee30c577 0 (Wed May 09 11:57:52 2012 +0200) {'user': 'Pierre-Yves David <pierre-yves.david@logilab.fr>'}