extend network protocol to stop clients from locking servers now all repositories have capabilities slot, tuple with list of names. if 'unbundle' capability present, repo supports push where client does not need to lock server. repository classes that have unbundle capability also have unbundle method. implemented for ssh now, will be base for push over http. unbundle protocol acts this way. server tells client what heads it has during normal negotiate step. client starts unbundle by repeat server's heads back to it. if server has new heads, abort immediately. otherwise, transfer changes to server. once data transferred, server locks and checks heads again. if heads same, changes can be added. else someone else added heads, and server aborts. if client wants to force server to add heads, sends special heads list of 'force'.

(the addremove command is deprecated; use add and remove --after instead)
adding foo
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
pulling from ../branch
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
(run 'hg update' to get a working copy)
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 2 changesets, 2 total revisions
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
foo
bar
6f4310b00b9a147241b071a60c28a650827fb03d 644 foo