Re: master^ is not a local branch -- huh?!?

From: Ron Garret <ron1@flownet.com>
Date: Jan 29, 2010, 21:34 UTC
Message-ID: <ron1-1F1799.13340029012010@news.gmane.org>
In-Reply-To: <op.u7a909hf4oyyg1@alvarezp-ws>

In article <op.u7a909hf4oyyg1@alvarezp-ws>,
 "Octavio Alvarez" <alvarezp@alvarezp.ods.org> wrote:

Show 32 quoted lines

> On Fri, 29 Jan 2010 12:20:46 -0800, Ron1 <ron1@flownet.com> wrote:
> 
> > [ron@mickey]$ git checkout master
> > Already on 'master'
> > [ron@mickey]$ git checkout master^
> > Note: moving to 'master^' which isn't a local branch
> > If you want to create a new branch from this checkout, you may do so
> > (now or later) by using -b with the checkout command again. Example:
> >   git checkout -b <new_branch_name>
> > HEAD is now at 7be05e0... test
> > [ron@mickey]$ git branch
> > * (no branch)
> >   master
> > [ron@mickey]$
> >
> > Huh?!?
> >
> > This is a test repository which has never been pulled from nor pushed to
> > anywhere.  So how is it possible that I have a non-local branch?
> 
> "Is a non-local branch" is not the same as "is not a local branch".
> 
> Think "branches" as tags that advance when you commit over them.
> 
> If you do gitk --all, only those commits with a green tag are
> "branches".
> 
> It means that if you switch to master^ and commit, your commit will
> be applied but not tracked (since there is not any branch to advance).
> 
> You would need to do git checkout -b 'new_branch', and then commit.
> Now, new_branch will advance with your new commit.

OK, I think I understand that.

Here's the thing: I can do this:

git checkout commit-id filename

and restore a particular revision of a particular file to my working tree without affecting my HEAD pointer. I would expect then that

git checkout commit-id

with no filename would do the same thing, except restore the entire tree from that commit (including deleting files that didnt' exist then). And indeed it does that (or at least appears to -- I haven't explored this in depth), except that it DOES move my HEAD pointer to this weird non-branch thing.

Here's what I think would be the correct behavior:

[ron@mickey]$ git checkout master^

"WARNING: master^ is not a branch. It is a commit on the master branch. Since the the commit you are asking for is on the same branch as your current HEAD pointer, here's what I'm going to do:

1.  Copy the master^ commit to your working tree
2.  Leave your HEAD pointer where is was (i.e. pointing to the head
of the master branch).

If this is not what you wanted, you can undo it by typing "git checkout HEAD". Also, in the future, you can avoid this warning by typing ... instead.

Or something like that.

rg