D342: rebase: change "result would have 3 parent" error message (BC)

[quark (Jun Wu)]

quark added a comment.


  I guess the old error message was intended for the below case:
  
    $ hg debugdrawdag <<'EOF'
    >   H
    >  /|
    > D F
    > | |\
    > C E G
    >  \|/
    >   B Z
    >   |/
    >   A
    > EOF
    $ hg rebase -d Z -r 'C+E+G+H'
  
  Removing D, having C connected to H directly is another interesting case. I think `adjustdest` could be changed to detect that situation (when adjusting H's destination considering its parent F, there are multiple candidates - E and G that may worth a warning or an error. Things could be more fun if E and G has obsolete or ancestor relationship).

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D342

To: quark, #hg-reviewers
Cc: martinvonz, mercurial-devel