Add a "quick and dirty" way to get execution times for test cases

[hop]

I would like some way to quickly (i.e. without having to modify the test suite) get timing data for test cases, as well as a sum total for the whole test suite.

Something like --durations but with an optional (or automatically determined, like with timeit) number of repetitions.

Would this be a fit for this plugin?

[ionelmc]

You could stick a contraption like this in your conftest.py:

from functools import wraps
from pytest import Function


def pytest_collection_modifyitems(items):
    for item in items:
        if 'benchmark' not in getattr(item, 'fixturenames', ()) and isinstance(item, Function):
            item.fixturenames.append('benchmark')
            item._fixtureinfo.argnames += 'benchmark',
            def wrap(obj):
                @wraps(obj)
                def test_wrapper(benchmark, **kwargs):
                    benchmark.pedantic(obj, kwargs=kwargs, iterations=1, rounds=1)
                return test_wrapper
            item.obj = wrap(item.obj)

Note that there's no summing of totals, but you could do it by using benchmark.stats['min'] (or max, mean, avg etc) inside the test_wrapper func.

[ionelmc]

Another problem is that wrong __module__ is set on test_wrapper, so your output will look like:

plugins: benchmark-3.1.0a2
collected 2 items

tests.py::test_foo <- conftest.py PASSED
tests.py::test_bar <- conftest.py PASSED

You can fix if by patching, and it's left as exercise to the reader 😬

[ionelmc]

Almost forgot, this works with function tests, dunno (or care 😁) about TestCase-style tests.

[hop]

Worked great, thank you! unittest2pytest took care of the TestCase detritus.

[blueyed]

This should be included by default, or at least be documented!

I've noticed that it does not work for parametrized fixtures.

I've not found a solution, but the difference there is that the item has a callspec.

The problem is:

TypeError: test_parametrized() got an unexpected keyword argument 'benchmark'

for item in items:
    if ('benchmark' not in getattr(item, 'fixturenames', ()) and
            isinstance(item, Function)):
        if hasattr(item, 'callspec'):
            item = item._pyfuncitem
        item.fixturenames.append('benchmark')
        item._fixtureinfo.argnames += 'benchmark',

        def wrap(obj):
            @wraps(obj)
            def test_wrapper(benchmark, **kwargs):
                benchmark.pedantic(obj, kwargs=kwargs, iterations=1,
                                   rounds=1)
            return test_wrapper
        item.obj = wrap(item.obj)

[ionelmc]

Oooof ... so should there be a cookbook section or something in the docs? What else should it have?

[chrahunt]

pytest already gives execution times for test suites and test cases. Execute pytest with --junitxml=output.xml and inspect the output - an aggregate time is provided on testsuite nodes and individual times are given on testcase nodes. For example:

<?xml version="1.0" encoding="utf-8"?>
<testsuite errors="0" failures="0" name="pytest" skips="1" tests="7" time="8.512">
    <testcase classname="tests.test_import_times"
              file="tests/test_import_times.py"
              line="83"
              name="test_fn[site]"
              time="2.0289511680603027">
    </testcase>
    <testcase classname="tests.test_import_times"
              file="tests/test_import_times.py"
              line="83"
              name="test_fn[asyncio]"
              time="1.1191785335540771">
    </testcase>
    <!-- ... -->
</testsuite>

Is this different than what was requested in the original issue?

[hop]

@chrahunt that would be the same as --durations, I believe, so no, not what I wanted at all.