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).
This feature requires mercurial 3.0
(and the `only()` revset is 3.0 specific)
$ (hg help revset | grep '"only(' > /dev/null) || exit 80
Test creation of obsolescence marker by path import
$ hg init auto-obsolete
$ cd auto-obsolete
$ echo '[extensions]' >> $HGRCPATH
$ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
$ echo A > a
$ hg commit -Am A
adding a
$ echo B > b
$ hg commit -Am B
adding b
$ hg up '.^'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo C > c
$ hg commit -Am C
adding c
created new head
$ hg log -G
@ changeset: 2:eb8dd0f31b51
| tag: tip
| parent: 0:f2bbf19cf96d
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: C
|
| o changeset: 1:95b760afef3c
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: B
|
o changeset: 0:f2bbf19cf96d
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: A
(actual test)
$ hg export 'desc(B)' | hg import - --obsolete
applying patch from stdin
$ hg log -G
@ changeset: 3:00c49133f17e
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: B
|
o changeset: 2:eb8dd0f31b51
| parent: 0:f2bbf19cf96d
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: C
|
o changeset: 0:f2bbf19cf96d
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: A
$ hg debugobsolete
95b760afef3c234ffb3f9fd391edcb36e60921a4 00c49133f17e5e5a52b6ef1b6d516c0e90b56d8a 0 (*) {'user': 'test'} (glob)
$ hg rollback
repository tip rolled back to revision 2 (undo import)
working directory now based on revision 2
$ hg log -G
@ changeset: 2:eb8dd0f31b51
| tag: tip
| parent: 0:f2bbf19cf96d
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: C
|
| o changeset: 1:95b760afef3c
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: B
|
o changeset: 0:f2bbf19cf96d
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: A
$ hg debugobsolete