Re: [Qemu-devel] [PATCH] script: git script to compile every commit in a range of commits

[Peter Crosthwaite]

Hi,

On Sat, Jun 8, 2013 at 6:30 AM, Jeff Cody <address@hidden> wrote:
> On Fri, Jun 07, 2013 at 11:51:36AM -0500, Anthony Liguori wrote:
>> Laszlo Ersek <address@hidden> writes:
>>
>> > On 06/07/13 16:44, Jeff Cody wrote:
>> >
>> >> Thanks.  I can either do the above changes for a v2, or as follow on
>> >> patches.
>> >
>> > Whichever is easier for you, certainly! I'm fine with the script
>> > going-in as is.
>>
>> A suggestion I'll make is to split the script into two parts.
>
> Hi Anthony,
>
> I'm sorry, but I'm a bit confused by your suggestion.  I think I know
> what you are asking (see below), but I'm not positive.
>
>> git-bisect run is a terribly useful command and I use a bisect script
>> that looks like this:
>>
>>     #!/bin/sh
>>
>>     set -e
>>
>>     pushd ~/build/qemu
>>     make -j1 || exit 1
>>     popd
>>
>>     # Add right seed here
>>     if test "$1"; then
>>         "$@"
>>     fi
>>
>> I'm sure we all have bisect scripts like this.
>>
>> What you're proposing is very similar to bisect but instead of doing a
>> binary search, it does a linear search starting from the oldest commit.
>> Basically:
>
> I agree that git bisect is useful, but solves a slightly different
> problem than what I am looking to solve.
>
> For instance, in my working branches I have a whole stack of commits
> that I will rebase and squash into a set of sane patches before
> submitting.  To make sure I don't do something silly in that process,
> and create a patch X that does not build without patch X+1, I want to
> explicitly compile each patch, without skipping over any patches.
>
>
>>     #!/bin/sh
>>
>>     refspec="$1"
>>     shift
>>
>>     git rev-list $refspec | while read commit; do
>>         git checkout $commit
>>         "$@" || exit $?
>>     done
>>
>> And indeed, I have a local script called git-foreach to do exactly
>> this.  I suspect a nicer version would make a very good addition to the
>> git project.
>>
>> So to bisect for a make check failure, I do:
>>
>>   git bisect run bisect.sh make check
>>
>> Or to bisect for a qemu-test failure:
>>
>>   git bisect run bisect.sh qemu-test-regress.sh
>>
>> With git-foreach, you can do:
>>
>>   git-foreach bisect.sh
>>
>> To do a simple build test.  Or you can do:
>>
>>   git-foreach git show checkpatch-head.sh
>>
>> etc.
>
> Ah!  So if I understand correctly, what you are asking is to split
> the script up into two different scripts:
>
> 1.) A 'foreach' framework script to run an arbitrary command over a
> range of commits, against each commit  (i.e. in the place where I run
> 'make clean, git checkout, configure, and make [lines 188-191], simply
> do the git checkout and execute a passed script / command).
>
> 2.) A second script to perform the complication check, intended to be
> called by script 1).  We could then add additional scripts to be
> called by the 'foreach' framework patch as desired.
>
> Heck, if we wanted to, we could then even create a menu-drive
> meta-script to interactively run any number of tests (checkpatch,
> compilation, etc..) using that framework.
>

Make sense to me. I have a little script that does this stuff for me,
but my for-each mechanism runs using git am rather than commit ranges
and git checkout. Verifies that the series as-about-to-be-sent applies
cleanly to the master without build breakage or checkpatch fail.

If you make this two stage split developers can choose between either
a commit or am based foreach iterator and the second script as your
call it is common to both.

Regards,
Peter

>>
>> Regards,
>>
>> Anthony Liguori
>>
>
> Thanks,
>
> Jeff
>