wireproto: implement command executor interface for version 1 peers
Now that we've defined our new interface for issuing commands,
let's implement it.
We add the interface to the base peer interface. This means all
peer types must implement it.
The only peer types that we have are the local peer in localrepo
and a shared wire peer for version 1 of the wire protocol.
The local peer implementation is pretty straightforward. We
don't do anything fancy and just return a resolved future with
the result of a method call. This is similar to what
localiterbatcher does.
The wire protocol version 1 implementation is a bit more complicated
and is a more robust implementation.
The wire executor queues commands by default. And because the new
executor interface always allows multiple commands but not all version
1 commands are @batchable, it has to check that the requested commands
are batchable if multiple commands are being requested.
The wire executor currently only supports executing a single command.
This is for simplicity reasons. Support for multiple commands will
be added in a separate commit.
To prove the new interface works, a call to the "known" command
during discovery has been updated to use the new API.
It's worth noting that both implementations require a method having
the command name to exist on the peer. There is at least one caller
in core that don't have a method calls peer._call() directly. We
may need to shore up the requirements later...
Differential Revision: https://phab.mercurial-scm.org/D3268
Corrupt an hg repo with a pull started during an aborted commit
Create two repos, so that one of them can pull from the other one.
$ hg init source
$ cd source
$ touch foo
$ hg add foo
$ hg ci -m 'add foo'
$ hg clone . ../corrupted
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo >> foo
$ hg ci -m 'change foo'
Add a hook to wait 5 seconds and then abort the commit
$ cd ../corrupted
$ echo "[hooks]" >> .hg/hgrc
$ echo 'pretxncommit = sh -c "sleep 5; exit 1"' >> .hg/hgrc
start a commit...
$ touch bar
$ hg add bar
$ hg ci -m 'add bar' &
... and start a pull while the commit is still running
$ sleep 1
$ hg pull ../source 2>/dev/null
pulling from ../source
transaction abort!
rollback completed
abort: pretxncommit hook exited with status 1
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets 52998019f625
(run 'hg update' to get a working copy)
see what happened
$ wait
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 2 changesets, 2 total revisions
$ cd ..