pop, followed by push should be a no-op

[smoofra]

It seems to me that pop, followed immediately by a push, with no changes in between, should be a no-op. It should leave the log in exactly the same state as it was before, because nothing important has changed. Couldn't this be accomplished by simply resetting the log branch to an earlier commit? It would be nice to not have the log cluttered up by operations that just cancel each other out.