# $> git branch splat response considered harmful

6 messages from 2019-08-08 to 2019-08-09. Participants: jim.cromie@gmail.com, Bryan Turner, Emily Shaffer, SZEDER Gábor, Junio C Hamano, Philip Oakley.
Thread: https://gitlist.dev/t/51610

## jim.cromie@gmail.com, 2019-08-08 21:08

Subject: $> git branch splat response considered harmful
Message-ID: <CAJfuBxx5R28cjUj1v+mB4J+uUpbTMWnYowrCc=iOAbOcqWX-_w@mail.gmail.com>
URL: https://gitlist.dev/e/CAJfuBxx5R28cjUj1v%2BmB4J%2BuUpbTMWnYowrCc%3DiOAbOcqWX-_w%40mail.gmail.com

```
fwiw,

jimc@frodo:~/prj-1/capnproto.git$ git branch -l
* master

I find the splat in the response unhelpful
when wrapped in shell for loop, the splat expands into everything in
current directory

jimc@frodo:~/prj-1/capnproto.git$ for b in `git branch -l`; do echo $b; done
appveyor.yml
c++
CMakeLists.txt
CONTRIBUTORS
...

it would be nice if some flag combo would suppress that splat.
save me from fugly brittle sh $IFS fiddlery and incomplete workarounds

git branch -l  # no splat
  master
git branch # splat ok for back-compat (if you think it necessary)
  * master

it appears that by convention, checked out branch is both 1st in list,
and splatted,
perhaps _DIRTY_, JUNK, or maybe "" would be good 1st line of response
if not on a branch ?

also, I found no mention of the splat in the man page.

```

## Bryan Turner, 2019-08-08 21:20

Subject: Re: $> git branch splat response considered harmful
Message-ID: <CAGyf7-FUsfKpr+HzOpS9TqE+x7GTnsVKki94gXzMVRwnnweC9g@mail.gmail.com>
URL: https://gitlist.dev/e/CAGyf7-FUsfKpr%2BHzOpS9TqE%2Bx7GTnsVKki94gXzMVRwnnweC9g%40mail.gmail.com
In-Reply-To: <CAJfuBxx5R28cjUj1v+mB4J+uUpbTMWnYowrCc=iOAbOcqWX-_w@mail.gmail.com>

```
On Thu, Aug 8, 2019 at 2:08 PM <jim.cromie@gmail.com> wrote:
>
> fwiw,
>
> jimc@frodo:~/prj-1/capnproto.git$ git branch -l
> * master
>
> I find the splat in the response unhelpful
> when wrapped in shell for loop, the splat expands into everything in
> current directory
>
> jimc@frodo:~/prj-1/capnproto.git$ for b in `git branch -l`; do echo $b; done
> appveyor.yml
> c++
> CMakeLists.txt
> CONTRIBUTORS
> ...
>
> it would be nice if some flag combo would suppress that splat.
> save me from fugly brittle sh $IFS fiddlery and incomplete workarounds

Have you tried "git for-each-ref --format="%(refname:short)"
refs/heads/"? That's going to provide short names for branches without
any indicator for the default branch, and without any special
ordering.

```

## Emily Shaffer, 2019-08-08 21:28

Subject: Re: $> git branch splat response considered harmful
Message-ID: <CAJoAoZ=K0LhCmnEUk1rsan2J5APzcye7+RryjBG+mKgjGf6qzA@mail.gmail.com>
URL: https://gitlist.dev/e/CAJoAoZ%3DK0LhCmnEUk1rsan2J5APzcye7%2BRryjBG%2BmKgjGf6qzA%40mail.gmail.com
In-Reply-To: <CAGyf7-FUsfKpr+HzOpS9TqE+x7GTnsVKki94gXzMVRwnnweC9g@mail.gmail.com>

```
On Thu, Aug 8, 2019 at 2:20 PM Bryan Turner <bturner@atlassian.com> wrote:
>
> On Thu, Aug 8, 2019 at 2:08 PM <jim.cromie@gmail.com> wrote:
> >
> > fwiw,
> >
> > jimc@frodo:~/prj-1/capnproto.git$ git branch -l
> > * master
> >
> > I find the splat in the response unhelpful
> > when wrapped in shell for loop, the splat expands into everything in
> > current directory
> >
> > jimc@frodo:~/prj-1/capnproto.git$ for b in `git branch -l`; do echo $b; done
> > appveyor.yml
> > c++
> > CMakeLists.txt
> > CONTRIBUTORS
> > ...
> >
> > it would be nice if some flag combo would suppress that splat.
> > save me from fugly brittle sh $IFS fiddlery and incomplete workarounds
>
> Have you tried "git for-each-ref --format="%(refname:short)"
> refs/heads/"? That's going to provide short names for branches without
> any indicator for the default branch, and without any special
> ordering.

More generally, I think you should take a look at `git help git` and
check out the difference between "porcelain" and "plumbing" commands.
The former, of which `git branch` is one, are intended for interactive
use and not really meant for scripting or piping. You can usually come
up with an equivalent from the plumbing commands, which Bryan has
suggested for you with `git for-each-ref`.  Git project tries very
hard to maintain output format of the plumbing commands so as to not
break folks' scripts, but such promises aren't usually made for
porcelain commands.

-- 
Emily Shaffer

```

## SZEDER Gábor, 2019-08-08 21:30

Subject: Re: $> git branch splat response considered harmful
Message-ID: <20190808213002.GI20404@szeder.dev>
URL: https://gitlist.dev/e/20190808213002.GI20404%40szeder.dev
In-Reply-To: <CAJfuBxx5R28cjUj1v+mB4J+uUpbTMWnYowrCc=iOAbOcqWX-_w@mail.gmail.com>

```
On Thu, Aug 08, 2019 at 03:08:06PM -0600, jim.cromie@gmail.com wrote:
> fwiw,
> 
> jimc@frodo:~/prj-1/capnproto.git$ git branch -l
> * master
> 
> I find the splat in the response unhelpful
> when wrapped in shell for loop, the splat expands into everything in
> current directory
> 
> jimc@frodo:~/prj-1/capnproto.git$ for b in `git branch -l`; do echo $b; done
> appveyor.yml
> c++
> CMakeLists.txt
> CONTRIBUTORS
> ...
> 
> it would be nice if some flag combo would suppress that splat.
> save me from fugly brittle sh $IFS fiddlery and incomplete workarounds

'git branch' is not intended for scripting, try 'git for-each-ref'
instead.  The equivalent command should be:

  git for-each-ref --format='%(refname:strip=2)' refs/heads/

> also, I found no mention of the splat in the man page.

It's in the first sentence of the description :)

  If --list is given, or if there are no non-option arguments, existing
  branches are listed; the current branch will be highlighted in green
  and marked with an asterisk.


```

## Junio C Hamano, 2019-08-08 21:46

Subject: Re: $> git branch splat response considered harmful
Message-ID: <xmqqo90ze3eq.fsf@gitster-ct.c.googlers.com>
URL: https://gitlist.dev/e/xmqqo90ze3eq.fsf%40gitster-ct.c.googlers.com
In-Reply-To: <CAJoAoZ=K0LhCmnEUk1rsan2J5APzcye7+RryjBG+mKgjGf6qzA@mail.gmail.com>

```
Emily Shaffer <emilyshaffer@google.com> writes:

> More generally, I think you should take a look at `git help git` and
> check out the difference between "porcelain" and "plumbing" commands.
> The former, of which `git branch` is one, are intended for interactive
> use and not really meant for scripting or piping. You can usually come
> up with an equivalent from the plumbing commands, which Bryan has
> suggested for you with `git for-each-ref`.  Git project tries very
> hard to maintain output format of the plumbing commands so as to not
> break folks' scripts, but such promises aren't usually made for
> porcelain commands.

Thanks for a detailed response.

Git project promises that output format of the Porcelain commands is
subject to change, in order to support human eyeballs better.

Unless documented otherwise (e.g. "git status --porcelain"), it is
unwise to try parsing porcelain output---your script may break any
time and you get to keep both halves.

That is not the same as saying "do not script using Porcelain".
Sending the output directly to the end user (e.g. compute the
revision range in your script that finally calls "git log" using
that computed revision range) is perfectly fine.

Thanks.

```

## Philip Oakley, 2019-08-09 18:01

Subject: Re: $> git branch splat response considered harmful
Message-ID: <5f533351-3d77-3859-fe27-b3d96b0b8b30@iee.email>
URL: https://gitlist.dev/e/5f533351-3d77-3859-fe27-b3d96b0b8b30%40iee.email
In-Reply-To: <CAJoAoZ=K0LhCmnEUk1rsan2J5APzcye7+RryjBG+mKgjGf6qzA@mail.gmail.com>

```
On 08/08/2019 22:28, Emily Shaffer wrote:
> On Thu, Aug 8, 2019 at 2:20 PM Bryan Turner <bturner@atlassian.com> wrote:
>> On Thu, Aug 8, 2019 at 2:08 PM <jim.cromie@gmail.com> wrote:
>>> fwiw,
>>>
>>> jimc@frodo:~/prj-1/capnproto.git$ git branch -l
>>> * master
>>>
>>> I find the splat in the response unhelpful
>>> when wrapped in shell for loop, the splat expands into everything in
>>> current directory
>>>
>>> jimc@frodo:~/prj-1/capnproto.git$ for b in `git branch -l`; do echo $b; done
>>> appveyor.yml
>>> c++
>>> CMakeLists.txt
>>> CONTRIBUTORS
>>> ...
>>>
>>> it would be nice if some flag combo would suppress that splat.
>>> save me from fugly brittle sh $IFS fiddlery and incomplete workarounds
>> Have you tried "git for-each-ref --format="%(refname:short)"
>> refs/heads/"? That's going to provide short names for branches without
>> any indicator for the default branch, and without any special
>> ordering.
> More generally, I think you should take a look at `git help git` and
> check out the difference between "porcelain" and "plumbing" commands.
> The former, of which `git branch` is one, are intended for interactive
> use and not really meant for scripting or piping. You can usually come
> up with an equivalent from the plumbing commands, which Bryan has
> suggested for you with `git for-each-ref`.  Git project tries very
> hard to maintain output format of the plumbing commands so as to not
> break folks' scripts, but such promises aren't usually made for
> porcelain commands.
>
I think this (the broad Q&A) also suggests that the porcelain command 
documentation could be more helpful for pointing to the appropriate 
plumbing commands for these scripting issues (and it could reduce list 
noise..).
--
Philip

```
