Re: [PATCH 3/4] qemu-iotests: let "check" spawn an arbitrary test command

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

23.03.2021 16:06, Paolo Bonzini wrote:
> Right now there is no easy way for "check" to print a reproducer command.
> Because such a reproducer command line would be huge, we can instead teach
> check to start a command of our choice.  This can be for example a Python
> unit test with arguments to only run a specific subtest.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   tests/qemu-iotests/check | 16 ++++++++++++++--
>   1 file changed, 14 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
> index d1c87ceaf1..aab25dac6a 100755
> --- a/tests/qemu-iotests/check
> +++ b/tests/qemu-iotests/check
> @@ -19,6 +19,7 @@
>   import os
>   import sys
>   import argparse
> +import shutil
>   from findtests import TestFinder
>   from testenv import TestEnv
>   from testrunner import TestRunner
> @@ -100,8 +101,8 @@ def make_argparser() -> argparse.ArgumentParser:
>                          'one to TEST (not inclusive). This may be used to '
>                          'rerun failed ./check command, starting from the '
>                          'middle of the process.')
> -    g_sel.add_argument('tests', metavar='TEST_FILES', nargs='*',
> -                       help='tests to run')
> +    g_sel.add_argument('tests', nargs=argparse.REMAINDER,

Interesting that REMAINDER documentation disappeared from latest (3.9) python documentation https://docs.python.org/3.9/library/argparse.html , but exists here https://docs.python.org/3.8/library/argparse.html  (and no mark of deprecation)

> +                       help='tests to run, or "--" followed by a command')
>   
>       return p
>   
> @@ -114,6 +115,17 @@ if __name__ == '__main__':
>                     imgopts=args.imgopts, misalign=args.misalign,
>                     debug=args.debug, valgrind=args.valgrind)
>   
> +    if args.tests[0] == '--':
> +        del args.tests[0]
> +        cmd = args.tests
> +        env.print_env()
> +        exec_path = shutil.which(cmd[0])
> +        if exec_path is None:
> +            sys.exit('command not found: ' + cmd[0])
> +        cmd[0] = exec_path
> +        full_env = env.prepare_subprocess(cmd)
> +        os.execve(cmd[0], cmd, full_env)
> +
>       testfinder = TestFinder(test_dir=env.source_iotests)
>   
>       groups = args.groups.split(',') if args.groups else None
> 

I hope at some moment we'll run testcases with syntax like

./check -qcow2 test_name.ClassName.method_name

But a possibility to run any command under check script defined environment is a good thing anyway:
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

-- 
Best regards,
Vladimir