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).
Quitting an evolve in the middle (via ctrl-c or something) can leave things in a
weird intermediate state where hg thinks we're in the middle of an update
operation (or even just leave the 'merge' directory around without actually
indicating we're in the middle of *any* operation).
$ . $TESTDIR/testlib/common.sh
$ cat << EOF >> $HGRCPATH
> [extensions]
> rebase =
> evolve =
> [alias]
> l = log -G -T'{rev} {desc}'
> EOF
$ hg init interrupted-orphan
$ cd interrupted-orphan
$ echo apricot > a
$ hg ci -qAm apricot
$ echo banana > b
$ hg ci -qAm banana
Let's go back to amend 0 and make an orphan out of 1 (and a merge conflict to
test with)
$ hg up -q 0
$ echo blueberry > b
$ hg l
o 1 banana
|
@ 0 apricot
$ hg ci --amend -qAm 'apricot and blueberry'
1 new orphan changesets
$ hg l
@ 2 apricot and blueberry
* 1 banana
|
x 0 apricot
$ hg evolve --update --config hooks.precommit=false --config ui.merge=:other
move:[1] banana
atop:[2] apricot and blueberry
transaction abort!
rollback completed
abort: precommit hook exited with status 1
[255]
$ hg l
@ 2 apricot and blueberry
* 1 banana
|
x 0 apricot
$ cat b
banana
$ hg status --config commands.status.verbose=True
M b
# The repository is in an unfinished *evolve* state.
# No unresolved merge conflicts.
# To continue: hg evolve --continue
# To abort: hg evolve --abort
# To stop: hg evolve --stop
# (also see `hg help evolve.interrupted`)
$ ls .hg/evolvestate
.hg/evolvestate
$ cat b
banana
$ hg l
@ 2 apricot and blueberry
* 1 banana
|
x 0 apricot
Test various methods of handling that unfinished state
$ hg evolve --abort
evolve aborted
working directory is now at e1989e4b1526
$ ls .hg/evolvestate
ls: cannot access '?.hg/evolvestate'?: No such file or directory (re)
[2]
$ cat b
blueberry
$ hg l
@ 2 apricot and blueberry
* 1 banana
|
x 0 apricot
$ hg evolve --update --config hooks.precommit=false --config ui.merge=:other
move:[1] banana
atop:[2] apricot and blueberry
transaction abort!
rollback completed
abort: precommit hook exited with status 1
[255]
$ cat b
banana
$ hg evolve --stop
stopped the interrupted evolve
working directory is now at e1989e4b1526
$ cat .hg/evolvestate
cat: .hg/evolvestate: No such file or directory
[1]
$ cat b
blueberry
$ hg l
@ 2 apricot and blueberry
* 1 banana
|
x 0 apricot
$ hg evolve --update --config hooks.precommit=false --config ui.merge=:other
move:[1] banana
atop:[2] apricot and blueberry
transaction abort!
rollback completed
abort: precommit hook exited with status 1
[255]
$ hg evolve --continue
evolving 1:e0486f65907d "banana"
working directory is now at bd5ec7dfc2af
$ cat .hg/evolvestate
cat: .hg/evolvestate: No such file or directory
[1]
$ cat b
banana
$ hg l
@ 3 banana
|
o 2 apricot and blueberry