Using lightweight branches (really helpful for working on Juju) I often would do the following:
bzr switch -b my-new-branch ... bzr switch trunk bzr pull bzr switch my-new-branch bzr merge
Aaron pointed out I can avoid switching to trunk to just do the pull by creating an alias like:
bzr alias pulltrunk="pull -d :parent"
(Though he suggested “-d :submit” my branches don’t have the submit branch as trunk so i changed as above. YMMV.)
So now I can just do:
bzr pulltrunk bzr merge