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Date: Mon, 16 Sep 2013 18:07:33 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] qom: helper macro for adding read-only
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, =?ISO-8859-1?Q?Andreas_F=E4rber?= <afaerber@suse.de>, Anthony Liguori <anthony@codemonkey.ws>, qemu-devel@nongnu.org

Il 16/09/2013 18:01, Michael S. Tsirkin ha scritto:
> On Mon, Sep 16, 2013 at 05:56:56PM +0200, Paolo Bonzini wrote:
>> Il 16/09/2013 17:48, Michael S. Tsirkin ha scritto:
>>> http://sweng.the-davies.net/Home/rustys-api-design-manifesto
>>>
>>> Even then: it will be at best
>>> "5. Do it right or it will always break at runtime."
>>>
>>> We need to switch to APIs at
>>> "9. The compiler/linker won't let you get it wrong."
>>
>> We definitely can get at least to "make check won't let you get it
>> wrong", which is somewhere in the middle.
>>
>> Paolo
> 
> We can't.
> make check just runs unit tests.
> So it can catch changes, but it can not catch bugs in new
> interfaces.

We can have "make check" run QEMU once for each board, which would trap
things that will always break at runtime such as a misspelled property.
 Similarly, we could have tests that try to instantiate every device,
even if they do not do anything with the guest-visible device.  Such
dummy tests can catch bugs in interface changes.

I look forward to discussing the future of qos and qtest at KVM Forum... :)

Paolo