Report on push/pull if heads are merged, too, like for new heads. Use case: If a remote repo has two heads and I _want_ to merge them, I merge and push. Meanwhile someone else pushed on top of one of the heads. He won't get a warning, because he doesn't create a new head, I won't notice that I don't close a head, because I don't get a message telling me.

     1

1 files updated, 0 files merged, 0 files removed, 0 files unresolved

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removing b

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this update spans a branch affecting the following files:

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 b

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aborting update spanning branches!

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(use 'hg merge' to merge across branches or 'hg update -C' to lose changes)