Re: [PATCH 1/1] Add --first-parent support to interactive rebase.

On 2007.10.30 22:05:27 -0700, Junio C Hamano wrote:

Your MUA seems to mark the UTF-8 message you are sending out as
8859-1, which means your name in the message gets corrupt.

Hm, that would be git-send-email then, anything I need to configure?
(Actually I don't see it marking the message as anything)

Björn Steinbrink [off-list ref] writes:

quoted

By default, rebase will take all commits from the branch that is to be
rebased which are missing in upstream. The new --first-parent option
allows to just follow the first parent and thus completely ignore
merges.

Additionally, when used together with --preserve-merges (which is the
more useful use-case) it will no longer rebase the commits from the
merged-in branches, but instead redo the merge with the original
parents.

That means that:

Given this situation:

quoted

     ---H------I topicB
    /    \      \
...
does no longer become:

Which results in:

quoted

                -H'--------I'
               /  \         \
              D'---E'---F'---G' topicA
             /
    A---B---C master
     \
      H---I topicB

When you do "git-rebase -p -i master topicA"

You can now also get:

quoted

    A---B---C master
...
        ---------H---------I topicB

When you do "git-rebase -p -i --first-parent master topicA"


That's better, right?

And crucially, you forgot to say "... when you do X".

I am assuming that you meant:

    This (picture) becomes this (picture) instead of this (picture)
    when you run "git rebase -p -m master topicA".

but without it, the nice ASCII drawings loses their value.

:-/

It is somewhat disturbing that this treats the first parent too
special.

The original use-case for the "-p -i --first-parent" case was a question
on #git, where someone had sth. like this:

   o---o---o---o---o remote/branch
        \           \
     o---o---o---o---o topicA
    /
   o---o---o master trunk

Now that guy was using git-svn to dcommit into svn from master. To
dcommit the changes from topicA he had to have that based on master, and
he wanted to preserve the merges from remote/branch to have them
squashed when dcommitted to svn. So what he wanted was:


     ...---o---o---o---o---o remote/branch
                \           \
             o---o---o---o---o topicA
            /
   o---o---o master trunk

The default behaviour of rebase would totally flat out the history and
instead of two sqaush merges (which he wanted), svn would've seen a huge
amount of commits comning from remote/branch. And the plain -p behaviour
would have duplicated all those branches from remote/branch for no good
reason, so I came up with that --first-parent thing.

Better ideas are welcome, I just don't know git well enough to come up
with anything better...

Thanks,
Björn