Re: [PATCH 1/2] iotests/065: Check for zstd support

[Vladimir Sementsov-Ogievskiy]

21.02.2022 20:08, Hanna Reitz wrote:
> Some test cases run in iotest 065 require zstd support.  Skip them if
> qemu-img reports it not to be available.
>
> Reported-by: Thomas Huth <thuth@redhat.com>
> Fixes: 12a936171d71f839dc907ff ("iotest 065: explicit compression type")
> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
> ---
>   tests/qemu-iotests/065 | 11 ++++++++---
>   1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/tests/qemu-iotests/065 b/tests/qemu-iotests/065
> index f7c1b68dad..b68df84642 100755
> --- a/tests/qemu-iotests/065
> +++ b/tests/qemu-iotests/065
> @@ -24,7 +24,7 @@ import os
>   import re
>   import json
>   import iotests
> -from iotests import qemu_img, qemu_img_pipe
> +from iotests import qemu_img_pipe, qemu_img_pipe_and_status
>   import unittest
>   
>   test_img = os.path.join(iotests.test_dir, 'test.img')
> @@ -35,8 +35,13 @@ class TestImageInfoSpecific(iotests.QMPTestCase):
>       def setUp(self):
>           if self.img_options is None:
>               self.skipTest('Skipping abstract test class')
> -        qemu_img('create', '-f', iotests.imgfmt, '-o', self.img_options,
> -                 test_img, '128K')
> +        output, status = qemu_img_pipe_and_status('create',
> +                                                  '-f', iotests.imgfmt,
> +                                                  '-o', self.img_options,
> +                                                  test_img, '128K')
> +        if status == 1 and \
> +                "'compression-type' does not accept value 'zstd'" in output:
> +            self.case_skip('zstd compression not supported')
>   
>       def tearDown(self):
>           os.remove(test_img)


Hmm. Actually you fix the commit 12a936171d71f in a meaning that test passes 
now. But that only stresses the fact that 12a936171d71f brings a degradation in 
test-count for no-zstd builds. Is it bad?
The simplest solution is to duplicate TestQCow3NotLazy and TestQCow3LazyQMP 
with s/zstd/zlib/.. More complicated is to add generic function to detect is 
zstd supported or not, and use zstd in TestQCow3NotLazy and TestQCow3NotLazy 
only if zstd is supported (and otherwise use zlib).

--
Best regards,
Vladimir