Re: [PATCH] for-each-ref: `:short` format for `refname`

From: Bert Wesarg <bert.wesarg@googlemail.com>
Date: Sep 2, 2008, 07:26 UTC
Message-ID: <36ca99e90809020026j37c41a8fu99b45abbd02eb372@mail.gmail.com>
In-Reply-To: <36ca99e90809011444v3fca09c4o4d9dcf1a7249a00a@mail.gmail.com>

On Mon, Sep 1, 2008 at 23:44, Bert Wesarg <bert.wesarg@googlemail.com> wrote:

Show 19 quoted lines

> On Mon, Sep 1, 2008 at 23:28, Junio C Hamano <gitster@pobox.com> wrote:
>> "Bert Wesarg" <bert.wesarg@googlemail.com> writes:
>>
>>> On Mon, Sep 1, 2008 at 21:10, Shawn O. Pearce <spearce@spearce.org> wrote:
>>> ...
>>>> You can still get ambiguous names.  Avoiding them requires going
>>>> through all refs and building their short forms, then using the
>>>> full ref name for any ref which had more than one name shorten to
>>>> the same string.  Ugly, but implementable, and probably something
>>>> that should be considered.
>>>
>>> What about: try the list backwards until the first match, than try the
>>> matched part (this what %.*s matched) with the forward list, if both
>>> give the same pattern, its not disambiguous. If not try the next
>>> pattern backwards.
>>
>> How does it catch the case where you have both 'xyzzy' branch and 'xyzzy'
>> tag, which is the point of disambiguation issue Shawn raised?
> Right.

I was wrong:

given these two refs:

  refs/heads/xyzzy
  refs/tags/xyzzy

first try to shorten "refs/heads/xyzzy":

  first (from the end) matched pattern is "refs/heads/%.*s" with
"xyzzy" as result

  but resolved ref for "xyzzy" is "refs/tags/xyzzy" => continue

  next matched pattern is "%.*s" with "refs/heads/xyzzy" as result

  end result is therefore: "refs/heads/xyzzy"

second try to shorten "refs/tags/xyzzy":

  first (from the end) matched pattern is "refs/tags/%.*s" with
"xyzzy" as result

  resolved ref for "xyzzy" is "refs/tags/xyzzy" => end

  end result is therefore: "xyzzy"

the output would be:

  refs/heads/xyzzy
  xyzzy

The question is now, if this is usable for bash completion? Current bash completion would handle this case wrong, because you get two xyzzy.

Bert