Re: [Qemu-devel] [PATCH 7/9] iotests: 'new' module replacement in 169

[Eduardo Habkost <ehabkost@redhat.com>]

On Mon, Oct 15, 2018 at 04:14:51PM +0200, Max Reitz wrote:
> iotest 169 uses the 'new' module to add methods to a class.  This module
> no longer exists in Python 3.  Instead, we can use a lambda.  Best of
> all, this works in 2.7 just as well.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  tests/qemu-iotests/169 | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/tests/qemu-iotests/169 b/tests/qemu-iotests/169
> index f243db9955..e5614b159d 100755
> --- a/tests/qemu-iotests/169
> +++ b/tests/qemu-iotests/169
> @@ -23,7 +23,6 @@ import iotests
>  import time
>  import itertools
>  import operator
> -import new
>  from iotests import qemu_img
>  
>  
> @@ -144,7 +143,7 @@ class TestDirtyBitmapMigration(iotests.QMPTestCase):
>  
>  def inject_test_case(klass, name, method, *args, **kwargs):
>      mc = operator.methodcaller(method, *args, **kwargs)
> -    setattr(klass, 'test_' + name, new.instancemethod(mc, None, klass))
> +    setattr(klass, 'test_' + name, lambda self: mc(self))

The "lambda self: mc(self)" expression looks weird and
unnecessary at first look, but I have just confirmed that this
doesn't work:

    setattr(klass, 'test_' + name, mc)

Probably because the methodcaller object won't automatically
become a instance method after the TestCase class is
instantiated.

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

>  
>  for cmb in list(itertools.product((True, False), repeat=4)):
>      name = ('_' if cmb[0] else '_not_') + 'persistent_'
> -- 
> 2.17.1
> 

-- 
Eduardo