Re: What's cooking in git.git (Mar 2010, #01; Wed, 03)

On Friday 05 March 2010 01:49:21 Junio C Hamano wrote:

Junio C Hamano [off-list ref] writes:

quoted

    $ git branch branch2                        <2>

I take it that this is supposed to be "checkout -b branch2".

    $ git reset --keep start                    <3>
    ------------

    <1> This commits your first edits in branch1.
    <2> This creates branch2, but unfortunately it contains the previous
    commit that you don't want in this branch.
    <3> This removes the unwanted previous commit, but this keeps the
    changes in your working tree.

The above sequence is not very convincing.  After you edited the second
time, you create branch2 and that is presumably because you realized that
the change in the work tree belongs to a separate topic.  It would be a
lot more natural to do this:

    $ git tag start ;# we do not have to tag, but just to make the
                       remainder of the illustration easier to read...
    $ git checkout -b branch1
    $ edit	    ;# do the work for the first topic
    $ git commit    ;# and commit
    $ edit          ;# start working more and then realize that the
    		       change belongs to a separate topic, and the previous
                       commit is unrelated to that new topic
    $ git checkout -b branch2 start
    $ edit          ;# continue working
    $ git commit    ;# and conclude it

so the example makes the use of "reset --keep" look artificial.

Nah, what was I thinking.  If I rephrase your side note <2> and <3> a
little bit, everything makes sense.  Perhaps like so:

    <2> In the ideal world, you could have realized that the earlier
    commit did not belong to the new topic when you created and switched
    to branch2 (i.e. "git checkout -b branch2 start"), but nobody is
    perfect.

    <3> But you can use "reset --keep" to remove the unwanted commit after
    you switched to "branch2".

And it becomes very clear that "reset --keep" is a sensible way to recover
from this mistake.  No need to do "read-tree -m -u" followed by "reset"
anymore.

Do you think I finally understood what "reset --keep" is about?

Yes I think so. Thanks for that.

I will rework the documentation patch according to your remarks and perhaps 
Jonathan Nieder's remarks too.

Thanks both,
Christian.