Re: [PATCH/RFC] builtin-checkout: suggest creating local branch when appropriate to do so

[Thomas Rast <trast@student.ethz.ch>]

Jeff King wrote:
> On Mon, Oct 05, 2009 at 11:17:09PM +0200, Johannes Schindelin wrote:
> 
> > > $ git checkout next
> > > error: pathspec 'next' did not match any file(s) known to git.
> > 
> > Actually, we should really think long and hard why we should not 
> > automatically check out the local branch "next" in that case.  I mean, 
> > really long and hard, and making sure to take user-friendliness into 
> > account at least as much as simplicity of implementation.
> 
> Some devil's advocate questions:
> 
>   1. How do we find "origin/next" given "next"? What are the exact
>      lookup rules? Do they cover every case? Do they avoid surprising
>      the user?
> 
>   2. What do we do if our lookup is ambiguous (e.g., "origin/next" and
>      "foobar/next" both exist)?
> 
>   3. If our lookup does have ambiguities or corner cases, is it better
>      to simply be suggesting to the user, rather than proceeding with an
>      action?

If I may add another:

4. Are there any (scripted?) use-cases where git-checkout should fail
   because it was given an invalid branch name?

The following gives a hint, though they could of course be fixed and
the ^0 case doesn't really count:

  $ git grep 'git checkout .*||' -- "*.sh"
  git-bisect.sh:          git checkout "$start_head" -- || exit
  git-rebase--interactive.sh:                     output git checkout $first_parent 2> /dev/null ||
  git-rebase--interactive.sh:                     output git checkout "$1" ||
  git-rebase.sh:git checkout -q "$onto^0" || die "could not detach HEAD"
  t/t2007-checkout-symlink.sh:git checkout -f master || exit

-- 
Thomas Rast
trast@{inf,student}.ethz.ch