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).
Tests for the --stop flag for `hg evolve` command while resolving phase-divergence
==================================================================================
The `--stop` flag stops the interrupted evolution and delete the state file so
user can do other things and comeback and do evolution later on
This is testing cases when `hg evolve` command is doing phase-divergence resolution.
Setup
=====
$ cat >> $HGRCPATH <<EOF
> [alias]
> glog = log -GT "{rev}:{node|short} {desc}\n ({bookmarks}) {phase}"
> [extensions]
> EOF
$ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
$ hg init stoprepo
$ cd stoprepo
$ echo ".*\.orig" > .hgignore
$ hg add .hgignore
$ hg ci -m "added hgignore"
$ for ch in a b c d; do echo foo > $ch; hg add $ch; hg ci -qm "added "$ch; done;
$ hg glog
@ 4:c41c793e0ef1 added d
| () draft
o 3:ca1b80f7960a added c
| () draft
o 2:b1661037fa25 added b
| () draft
o 1:c7586e2a9264 added a
| () draft
o 0:8fa14d15e168 added hgignore
() draft
Creating phase divergence, resolution of which will lead to conflicts
----------------------------------------------------------------------
$ hg up .^^^
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
$ hg pick -r .~-3
picking 4:c41c793e0ef1 "added d"
$ echo foobar > c
$ hg add c
$ hg amend
$ hg glog --hidden
@ 6:ddba58020bc0 added d
| () draft
| x 5:cfe30edc6125 added d
|/ () draft
| x 4:c41c793e0ef1 added d
| | () draft
| o 3:ca1b80f7960a added c
| | () draft
| o 2:b1661037fa25 added b
|/ () draft
o 1:c7586e2a9264 added a
| () draft
o 0:8fa14d15e168 added hgignore
() draft
$ hg phase -r c41c793e0ef1 --public --hidden
1 new phase-divergent changesets
$ hg glog
@ 6:ddba58020bc0 added d
| () draft
| o 4:c41c793e0ef1 added d
| | () public
| o 3:ca1b80f7960a added c
| | () public
| o 2:b1661037fa25 added b
|/ () public
o 1:c7586e2a9264 added a
| () public
o 0:8fa14d15e168 added hgignore
() public
$ hg evolve --phase-divergent
recreate:[6] added d
atop:[4] added d
rebasing to destination parent: ca1b80f7960a
merging c
warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
unresolved merge conflicts
(see 'hg help evolve.interrupted')
[1]
$ hg evolve --stop
stopped the interrupted evolve
working directory is now at ca1b80f7960a
XXX: maybe we should update wdir to where it was
$ hg glog
* 6:ddba58020bc0 added d
| () draft
| o 4:c41c793e0ef1 added d
| | () public
| @ 3:ca1b80f7960a added c
| | () public
| o 2:b1661037fa25 added b
|/ () public
o 1:c7586e2a9264 added a
| () public
o 0:8fa14d15e168 added hgignore
() public