Re: [RFC 1/1] acceptance tests: rename acceptance to system

[Thomas Huth <thuth@redhat.com>]

On 20/05/2021 22.28, Philippe Mathieu-Daudé wrote:
> On 5/20/21 9:53 PM, Willian Rampazzo wrote:
>> Conceptually speaking, acceptance tests "are a series of specific tests
>> conducted by the customer in an attempt to uncover product errors before
>> accepting the software from the developer. Conducted by the end-user rather
>> than software engineers, acceptance testing can range from an informal
>> “test drive” to a planned and systematically executed series of scripted
>> tests" [1]. Every time Pressman refers to the term "acceptance testing," he
>> also refers to user's agreement in the final state of an implemented feature.
>> Today, QEMU is not implementing user acceptance tests as described by Pressman.
>>
>> There are other three possible terms we could use to describe what is currently
>> QEMU "acceptance" tests:
>>
>>    1 - Integration tests:
>>        - "Integration testing is a systematic technique for constructing the
>>           software architecture while at the same time conducting tests to
>>           uncover errors associated with interfacing. The objective is to take
>>           unit-tested components and build a program structure that has been
>>           dictated by design." [2]
>>        * Note: Sommerville does not have a clear definition of integration
>>          testing. He refers to incremental integration of components inside
>>          the system testing (see [3]).

After thinking about this for a while, I agree with you that renaming the 
"acceptance" tests to "integration" tests is also not a good idea. When I 
hear "integration" test in the context of the virt stack, I'd rather expect 
a test suite that picks KVM (i.e. a kernel), QEMU, libvirt and maybe 
virt-manager on top and tests them all together. So we should look for a 
different name indeed.

>>    2 - Validation tests:
>>        - "Validation testing begins at the culmination of integration testing,
>>           when individual components have been exercised, the software is
>>           completely assembled as a package, and interfacing errors have been
>>           uncovered and corrected. At the validation or system level, the
>>           distinction between different software categories disappears. Testing
>>           focuses on user-visible actions and user-recognizable output from the
>>           system." [4]
>>        - "where you expect the system to perform correctly using a set of test
>>           cases that reflect the system’s expected use." [5]
>>        * Note: the definition of "validation testing" from Sommerville reflects
>>          the same definition found around the Internet, as one of the processes
>>          inside the "Verification & Validation (V&V)." In this concept,
>>          validation testing is a high-level definition that covers unit testing,
>>          functional testing, integration testing, system testing, and acceptance
>>          testing.
>>
>>    3 - System tests:
>>        - "verifies that all elements mesh properly and that overall system
>>           function and performance is achieved." [6]
>>        - "involves integrating components to create a version of the system and
>>           then testing the integrated system. System testing checks that
>>           components are compatible, interact correctly, and transfer the right
>>           data at the right time across their interfaces." [7]
>>
>> The tests implemented inside the QEMU "acceptance" directory depend on the
>> software completely assembled and, sometimes, on other elements, like operating
>> system images. In this case, the proposal here is to rename the current
>> "acceptance" directory to "system."
> 
> Are user-mode tests using Avocado also system tests?
> https://www.mail-archive.com/qemu-devel@nongnu.org/msg782505.html

We've indeed got the problem that the word "system" is a little bit 
overloaded in the context of QEMU. We often talk about "system" when 
referring to the qemu-softmmu-xxx emulators (in contrast to the linux-user 
emulator binaries). For example, the "--disable-system" switch of the 
configure script, or the "build-system" and "check-system" jobs in the 
.gitlab-ci.yml file ... thus this could get quite confusing in the 
.gitlab-ci.yml file afterwards.

So I think renaming "acceptance" to "system" is especially ok if we only 
keep the "softmmu"-related tests in that folder... would it maybe make sense 
to add the linux-user related tests in a separate folder called tests/user/ 
instead, Philippe? And we should likely rename the current build-system and 
check-system jobs in our gitlab-CI to build-softmmu and check-softmmu or so?

Alternatively, what about renaming the "acceptance" tests to "validation" 
instead? That word does not have a duplicated definition in the context of 
QEMU yet, so I think it would be less confusing.

  Thomas