On Wed, 2013-01-30 at 12:22 -0600, Kevin Bullock wrote:

It probably ought to look like this:

$ hg sum parent: 18473:692cbda1eb50 tip revset: evaluate sub expressions correctly (issue3775) branch: stable bookmarks: *@ commit: 15 unknown (clean) update: (current)

$ hg pull <some pull that moves @ out from under us>

$ hg sum parent: 18472:37100f30590f test-rebase: add another test for rebase with multiple roots branch: stable bookmarks: (@) commit: 15 unknown (clean) update: 1 new changesets (update)

Note the last line in particular: summary's calculation of the default update target probably needs attention. We possibly even want something like an update() revset predicate that tells us where we're going.

Also, something I encountered while constructing the last example: when we update to an ancestor of the active bookmark, we might want the bookmark to remain active, but not move:

$ hg up @ <- we're on @ $ hg up <- we go to @ if @ moved $ hg up @^ <- we hop off @, oops $ hg up <- we go to the branch tip, @ stops getting updated

Or, more expansively, we might want to only drop the active bookmark if we move to a commit outside of (::x or x::). So, for instance:

o-a-o-o-@-o-o-x (. = @) \ \ u o-o-y

hg up -> no-op, we're at @ hg up a -> we leave @ active, but go backwards hg up x -> we advance @ to x hg up y -> we advance @ to y hg up u -> @ is deactivated

But we probably don't want to do this in the case of updating to symbolic markers like tags, branches, other bookmarks, so this might be too complex.