[1/3] support/testing: replace nose2 with pytest - Dockerfile

From: Oguz Ozhan <oguz.ozhan@mind.com>

- From web page of nose2:
(https://docs.nose2.io/en/latest/)
nose2 vs pytest:
  - pytest is an excellent test framework and we encourage users to consider it for new projects.
  - It has a bigger team of maintainers and a larger community of users.

- pytest is more robust and has more ability compared to nose2

Signed-off-by: Oguz Ozhan <oguz.ozhan@mind.be>
---
 support/docker/Dockerfile | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Oguz, All,

On 2022-10-21 11:15 +0200, Oguz Ozhan spake thusly:
> From: Oguz Ozhan <oguz.ozhan@mind.com>
> 
> - From web page of nose2:
> (https://docs.nose2.io/en/latest/)
> nose2 vs pytest:
>   - pytest is an excellent test framework and we encourage users to consider it for new projects.
>   - It has a bigger team of maintainers and a larger community of users.

This clearly states "for new projects", but we are not new! ;-)

Why do we need to switch to pytest, and what does that bring us? (see
below too)

> - pytest is more robust and has more ability compared to nose2

You provide robustness and more abilities to advocate for switching to
pytest, however, you do not explain what is currently broken that would
be fixed by the pytest robustness, or what new features from pytest we
could leverage, and how.

Note that I am not opposed to switching, but we need a good rationale
for switching.

This commit should also come after we actually did the switch, i.e. we
should first convert support/testing/ over to pytest, then modify the
dockerfile accordingly, which allows to write a better coomit log.

Also, please organise your commit logs as (first line is the title):

    support/docker: install pytest instead of nose2

    Now that the tuntime test infra has switched to using pytest instead
    of nose2, install the appropriate packages in the Dockerfile for our
    reference build environment.

    Note that pytest-parallel is not available i Debian Bullseye, so we
    install it (and its depenencies) from Pypi instead.

    Signed-off-by: You

See more below...

> Signed-off-by: Oguz Ozhan <oguz.ozhan@mind.be>
> ---
>  support/docker/Dockerfile | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/support/docker/Dockerfile b/support/docker/Dockerfile
> index f54c31b54a..fd1527b1f9 100644
> --- a/support/docker/Dockerfile
> +++ b/support/docker/Dockerfile
> @@ -38,8 +38,8 @@ RUN apt-get install -y --no-install-recommends \
>          mercurial \
>          openssh-server \
>          python3 \
> +        python3-pip \
>          python3-flake8 \
> -        python3-nose2 \
>          python3-pexpect \
>          python3-pytest \
>          qemu-system-arm \
> @@ -53,6 +53,9 @@ RUN apt-get install -y --no-install-recommends \
>      apt-get -y autoremove && \
>      apt-get -y clean
>  
> +# To be able to run tests in parallel
> +RUN pip install pytest-parallel

Please, pin the version so that the image is reproducible.

Also, if pytest-parallel has dependencies, explicitly install those at
pinned versions too.

Also note in the commit log that pytest-parallel is not available in
bullseye, so we need to get it from Pypi instead (as in my suggestion).

Regards,
Yann E. MORIN.

>  # To be able to generate a toolchain with locales, enable one UTF-8 locale
>  RUN sed -i 's/# \(en_US.UTF-8\)/\1/' /etc/locale.gen && \
>      /usr/sbin/locale-gen
> -- 
> 2.34.1
> 
> _______________________________________________
> buildroot mailing list
> buildroot@buildroot.org
> https://lists.buildroot.org/mailman/listinfo/buildroot

Hello,

I am not against to switch to pytest.
But I didn't understand clearly yet the use case that motivated this series, in
which nose2 is not good and pytest is better. Could you elaborate?

Also, there are issues to be addressed before merging this series:
- the detection of a failed test on GitLab CI is broken, even tests failing
  return exit code 0, so GitLab infra mark them as PASS, see [1];
- run-tests -s is broken (does not show the build and runtime console);
- support to ask a single runtime test to run on GitLab CI is broken due to a
  regexp that needs to be adapted;
- the manual needs to be updated.

There are also some changes in behavior that would be nice to be highlighted:
- someone willing to find a test in the output of run-tests -l can do:
nose2:  run-tests -l 2>&1 | grep pattern
pytest: run-tests -l | grep pattern
- total number of tests:
nose2:  run-tests -l prints the number of tests at the end "Ran 481 tests"
pytest: run-tests -l does not
- the name of tests change (list)
nose2:  test_run (tests.toolchain.test_external_bootlin.\
        TestExternalToolchainBootlinPowerpc64lepower8GlibcBleedingEdge) ... ok
pytest: support/testing/tests/toolchain/test_external_bootlin.py::\
        TestExternalToolchainBootlinPowerpc64lepower8GlibcBleedingEdge::test_run
- the name of tests change (local run)
nose2:  support/testing/run-tests tests.init.test_busybox \
        tests.package.test_php_lua.TestPhpLuaLuajit
pytest: support/testing/run-tests support/testing/tests/init/test_busybox.py \
        support/testing/tests/package/test_php_lua.py::TestPhpLuaLua
- the name of tests change (gitlab test suite)
nose2:  git push gitlab HEAD:foo-tests.init.test_busybox
        see [2]
pytest: git push gitlab HEAD:foo-support/testing/tests/init/test_busybox.py
        see [3]
- the name of tests change (gitlab test case)
nose2:  git push gitlab HEAD:foo-tests.package.test_php_lua.TestPhpLuaLuajit
        see [4]
pytest: git push gitlab \
        HEAD:foo-support/testing/tests/package/test_php_lua.py--TestPhpLuaLuajit
        see [5]
        NOTICE: the use of '--' is just the first solution that came to mind.
- the name of tests are longer, so in the GitLab CI the display is a bit worse:
nose2:  tests.init.test_busybox.TestInitSystemBusyboxRo
        tests.init.test_busybox.TestInitSystemBusybox...
        tests.init.test_busybox.TestInitSystemBusybox...
        tests.init.test_busybox.TestInitSystemBusybox...
        tests.package.test_php_lua.TestPhpLuaLua
        tests.package.test_php_lua.TestPhpLuaLuajit
pytest: support/testing/tests/init/test_busybox.py::Tes...
        support/testing/tests/init/test_busybox.py::Tes...
        support/testing/tests/init/test_busybox.py::Tes...
        support/testing/tests/init/test_busybox.py::Tes...
        support/testing/tests/package/test_php_lua.p...
        support/testing/tests/package/test_php_lua.p...
- bash completion for the name of a test suite
nose2:  no completion
        support/testing/run-tests tests.init.test_busybox
pytest: since it uses the path as the begin of test name one can type
        'support/testing/run-tests support/testing' and use bash completion for
        test files names:
        support/testing/run-tests support/testing/tests/init/test_busybox.py
- cache of results
nose2:  no cache
pytest: it creates a .pytest_cache/ with a cache of the results, so we could
        later expose another parameter in run-tests that passes '-lf' to pytest,
        which will re-run only the tests that failed on last run
- verbosity when collecting tests:
nose2:  no output
pytest: prints a summary 'collected 1 item'
        'pytest-parallel: 1 worker (process), 1 test per worker (thread)'
- verbosity while tests are running:
nose2:  show states for each test (Starting, Building)
pytest: shows nothing before each test ends
- verbosity when tests fail:
nose2:  verbose
pytest: more verbose than nose2
- verbosity when tests pass:
nose2:  show states for each test (Starting, Building)
pytest: show only a '.' for each test

[1] https://gitlab.com/RicardoMartincoski/buildroot/-/jobs/3248620433
[2] https://gitlab.com/RicardoMartincoski/buildroot/-/pipelines/680878149
[3] https://gitlab.com/RicardoMartincoski/buildroot/-/pipelines/680879324
[4] https://gitlab.com/RicardoMartincoski/buildroot/-/pipelines/680879308
[5] https://gitlab.com/RicardoMartincoski/buildroot/-/pipelines/680878335

Regards,
Ricardo