Re: 'git branch' when origin branch with same name exists

On Tue, 19 Jun 2012 10:51:39 -0400
Ryan Lortie [off-list ref] wrote:

After helping someone on IRC who got themselves into a bit of a
problem, I have a feature request for git.

In this case, the user wanted to checkout a branch of a module.  They
did:

   git clone git://git.gnome.org/gtk+
   cd gtk+
   git branch gtk-3-4

Obviously this is a user error, but it's a pretty innocent one, and
puts the user in a bad state.
When they figure they should have
typed "git checkout gtk-3-4" it is already too late -- they will be
taken onto their locally-created copy of the master branch.

How bad this state really is?
The user is free to do
$ git branch -m gtk-3-4 mygtk-3-4
at any time after the error was detected.

So feature request: 'git branch' should not allow creating a local 
branch that has the same name as a branch that already exists on 
'origin' (or any remote?) without some sort of --force flag.  It
could instead helpfully say:

[...]

or something like that.

This would not protect from the obvious case when a branch has been
created on the remote (by someone else) but has not been fetched yet
and so the local repo does not know a branch with "conflicting"
name do exist.

Thoughts?

Your intention is good but I think a safety net of the kind you
propose would be slightly over the top.
Basically you're trying to compensate for the user error who
thinks the "branch" command should take her to an already existing
branch while it does something completely different.
Hence preventing the `git branch gtk-3-4` command from completion
should there be a remote-tracking branch of the same name is just wrong
IMO.  On the other hand, posting a hint might be OK.  I'm talking about
something like this:

$ git branch gtk-3-4
The remote "origin" has the branch of the same name.
The created branch is not set to track it.

Such a hint would state the obvious thing but it would alert a user
who would not expect it (and hopefully make her google or ask for
assistance using this hint's message).

Anyway, this will make each call to git-branch to perform a crawl over
the refs/heads hierarchy which, I think, is not worth the result.