Re: [Qemu-devel] [PATCH] iotests: handle TypeError for Python3 in test 242

[Eric Blake <eblake@redhat.com>]

[adding Eduardo for some python 2-vs-3 advice]

On 2/18/19 1:59 PM, Andrey Shinkevich wrote:
> To write one byte to disk, Python2 may use 'chr' type.
> In Python3, conversion to 'byte' type is required.
> 
> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
> ---
>  tests/qemu-iotests/242 | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/qemu-iotests/242 b/tests/qemu-iotests/242
> index 16c65ed..6b1f7b8 100755
> --- a/tests/qemu-iotests/242
> +++ b/tests/qemu-iotests/242
> @@ -65,9 +65,14 @@ def toggle_flag(offset):
>      with open(disk, "r+b") as f:
>          f.seek(offset, 0)
>          c = f.read(1)
> -        toggled = chr(ord(c) ^ bitmap_flag_unknown)
> +        toggled = ord(c) ^ bitmap_flag_unknown
>          f.seek(-1, 1)
> -        f.write(toggled)
> +        try:
> +            # python2
> +            f.write(chr(toggled))
> +        except TypeError:
> +            # python3
> +            f.write(bytes([toggled]))

Looks like it works, but I'm not enough of a python expert to know if
there is a more Pythonic elegant approach.

If someone else picks it up before my next NBD pull request,
Acked-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org