git-rev-parse --symbolic-abbrev-name [was Re: git-branch --print-current]

[Karl Chen <quarl@cs.berkeley.edu>]

>>>>> On 2009-01-03 21:17 PST, Junio C Hamano writes:

    Junio> That is a good point about user education, and is a
    Junio> demonstration why a new option to cover a very
    Junio> narrow-special case to symbolic-ref will not help the
    Junio> situation.  People will add their own embellishments
    Junio> around the name of the branch anyway, and the most
    Junio> generic symbolic-ref output is just as useful as a
    Junio> special case option to show without refs/heads/.

That's arguable :) you really think "branchfoo" instead of
"refs/heads/branchfoo" is a narrow special case?  Seems like a
common case for everyone except plumbing tools.

Here's a more general idea you might like better:

    git symbolic-ref --abbrev BLAH
or even
    git rev-parse --symbolic-abbrev-name BLAH

This would be like git-rev-parse --symbolic-full-name, but strips
the "refs/x/" iff the result is unambiguous.  Since it's much more
work for a script to check whether the stripped version is
ambiguous, this functionality is appropriate as a builtin option.

(Hmm, I guess to be able to specify a ref it has to already be
unambiguous, so the main use that --symbolic doesn't already cover
is for symbolic refs such as HEAD.)

    Junio> What you quoted are all inferior implementations of
    Junio> showing the name of the current branch in the bash
    Junio> prompt.

Yup, that was the point - it's so ugly seeing all these things
floating around, but that's where things stand right now.

    Junio> ... __git_ps1 shell function is defined to be used for
    Junio> this exact purpose and is documented in the completion
    Junio> script.

Thanks for the detailed explanation.  I actually use zsh rather
than of bash and I did already find git-completion.bash.  But
obviously all those people posting on blogs don't know about it :)