public inbox for git@vger.kernel.org 
 help / color / mirror / Atom feed

From: Junio C Hamano <gitster@pobox•com>
To: Jeff King <peff@peff•net>
Cc: "Crabtree\, Andrew" <andrew.crabtree@hp•com>,
	"git\@vger.kernel.org" <git@vger•kernel.org>
Subject: Re: Plumbing version of 'git branch --contains' ?
Date: Thu, 23 Oct 2014 11:07:13 -0700	[thread overview]
Message-ID: <xmqqd29islri.fsf@gitster.dls.corp.google.com> (raw)
In-Reply-To: <20141023171921.GA25061@peff.net> (Jeff King's message of "Thu, 23 Oct 2014 10:19:22 -0700")

Jeff King <peff@peff•net> writes:

> On Wed, Oct 22, 2014 at 08:19:07PM +0000, Crabtree, Andrew wrote:
>
>> I need to get a list of refs that can reach a certain SHA in in a script.
>> 
>> git branch --contains SHA 
>> 
>> would be great (runs in ~2 seconds), but not my preferred option for scripting.
>> 
>> I tried
>>  
>> for br in $(git for-each-ref --format='%(refname:short)' refs/heads/)
>> do
>>     git merge-base --is-ancestor $1 ${br}
>>     if [ $? -eq 0 ]
>>     then
>>             echo "${br}"
>>     fi
>> done
>> 
>> Which gives me perfect output, but takes 82 seconds to run in my environment.
>
> Right. There's some setup work that happens in `git branch --contains`
> that we end up repeating.
>
>> Is there an alternative I'm missing to give me the run time
>> performance of 'git branch --contains' but with stable output suitable
>> for parsing?
>
> Sadly, no, there isn't currently. The right tool would be `git
> for-each-ref --contains`, but it doesn't exist yet. I was working
> towards it, but got stopped on factoring out a `--contains` traversal
> suitable for both `git tag` and `git branch` (they currently are
> different and make performance tradeoffs based on the expected depth of
> the merge bases, which is usually different between tags and
> branches)[1].  That's work I'd love to resume, but I haven't gotten
> around to it yet.
>
> -Peff
>
> [1] http://thread.gmane.org/gmane.comp.version-control.git/252472

Thanks for status update.  I was wondering if I should start looking
into it myself.

     prev parent reply	other threads:[~2014-10-23 18:07 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-22 20:19 Plumbing version of 'git branch --contains' ? Crabtree, Andrew
2014-10-23 17:19 ` Jeff King
2014-10-23 18:07   ` Junio C Hamano [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=xmqqd29islri.fsf@gitster.dls.corp.google.com \
    --to=gitster@pobox$(echo .)com \
    --cc=andrew.crabtree@hp$(echo .)com \
    --cc=git@vger$(echo .)kernel.org \
    --cc=peff@peff$(echo .)net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox