unknown hook 'pytest_xdist_node_collection_finished' in plugin mozlog

[maxious]

A new version of pytest has been released (3.1.0) with some extra hook checking pytest-dev/pytest#1821

Rolling back to 3.0.7 resolves this for now.

> py.test
============================= test session starts ==============================
platform linux2 -- Python 2.7.12, pytest-3.1.0, py-1.4.33, pluggy-0.4.0
rootdir: /home/ubuntu/dto-digitalmarketplace-buyer-frontend, inifile: setup.cfg
plugins: cov-2.5.1, bdd-2.18.2, mozlog-3.4
collecting 422 itemsINTERNALERROR> Traceback (most recent call last):
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/main.py", line 105, in wrap_session
INTERNALERROR>     session.exitstatus = doit(config, session) or 0
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/main.py", line 140, in _main
INTERNALERROR>     config.hook.pytest_collection(session=session)
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/vendored_packages/pluggy.py", line 745, in __call__
INTERNALERROR>     return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/vendored_packages/pluggy.py", line 339, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/vendored_packages/pluggy.py", line 334, in <lambda>
INTERNALERROR>     _MultiCall(methods, kwargs, hook.spec_opts).execute()
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/vendored_packages/pluggy.py", line 614, in execute
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/main.py", line 150, in pytest_collection
INTERNALERROR>     return session.perform_collect()
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/main.py", line 605, in perform_collect
INTERNALERROR>     self.config.pluginmanager.check_pending()
INTERNALERROR>   File "/home/ubuntu/virtualenvs/venv-2.7.12/lib/python2.7/site-packages/_pytest/vendored_packages/pluggy.py", line 498, in check_pending
INTERNALERROR>     (name, hookimpl.plugin))
INTERNALERROR> PluginValidationError: unknown hook 'pytest_xdist_node_collection_finished' in plugin <mozlog.pytest_mozlog.plugin.MozLog object at 0x7f7a9056ead0>

[edmorley]

There has been a follow-up fix to the new feature which stops it reporting errors in some cases which it shouldn't (pytest-dev/pytest#2292), however I think this might actually not help here, since I think pytest-mozlog isn't marking the xdist plugin as optional, like so:
https://docs.pytest.org/en/latest/writing_plugins.html#optionally-using-hooks-from-3rd-party-plugins

[edmorley]

however I think this might actually not help here, since I think pytest-mozlog isn't marking the xdist plugin as optional

Yeah the followup in pytest didn't help, the issue still occurs in pytest 3.1.1.

[davehunt]

Sorry for the confusion, this repo was for an early prototype of a pytest-mozlog plugin. The actual source code is now to be found in mozlog itself: https://dxr.mozilla.org/mozilla-central/source/testing/mozbase/mozlog/mozlog/pytest_mozlog

I think all that's needed here is to mark the hooks as optional, such as:

@pytest.mark.optionalhook
def pytest_xdist_node_collection_finished(self, node, ids):
    '''Called after each pytest-xdist node collection is completed'''
    self._log_suite_start(ids)

Alternatively, install or add pytest-xdist as a dependency, but that not ideal as the pytest-mozlog plugin should work with or without pytest-xdist.

[davehunt]

I'll add a note to the README of this repo redirecting to the canonical source.

[davehunt]

Also, if you're not using pytest-mozlog and want to disable it, see https://docs.pytest.org/en/latest/usage.html?highlight=disable%20plugin#disabling-plugins for details, but something like pytest -p no:mozlog should work.

[davehunt]

This has now been raised as bug 1375145.