`tests/test_baseconverter.py::test_310_union_field_roundtrip`: `hypothesis.errors.FailedHealthCheck: It looks like this test is fi ltering out a lot of inputs...`

[mgorny]

============================================================== FAILURES ===============================================================
___________________________________________________ test_310_union_field_roundtrip ____________________________________________________

    @pytest.mark.skipif(not is_py310_plus, reason="3.10+ union syntax")
>   @settings(suppress_health_check=[HealthCheck.too_slow])
                   ^^^
E   hypothesis.errors.FailedHealthCheck: It looks like this test is filtering out a lot of inputs. 5 inputs were generated successfully
, while 50 inputs were filtered out. 
E   
E   An input might be filtered out by calls to assume(), strategy.filter(...), or occasionally by Hypothesis internals.
E   
E   Applying this much filtering makes input generation slow, since Hypothesis must discard inputs which are filtered out and try gener
ating it again. It is also possible that applying this much filtering will distort the domain and/or distribution of the test, leaving 
your testing less rigorous than expected.
E   
E   If you expect this many inputs to be filtered out during generation, you can disable this health check with @settings(suppress_heal
th_check=[HealthCheck.filter_too_much]). See https://hypothesis.readthedocs.io/en/latest/reference/api.html#hypothesis.HealthCheck for 
details.

f          = <function given.<locals>.run_test_as_given.<locals>.wrapped_test at 0x00007fed7dbe05c0>

tests/test_baseconverter.py:144: FailedHealthCheck
-------------------------------------------------------- Captured stdout call ---------------------------------------------------------
You can add @seed(190619015855193322801806182476062464120) to this test to reproduce this failure.

This is 25.2.0 with:

platform linux -- Python 3.11.13[pypy-7.3.20-final], pytest-8.4.1, pluggy-1.6.0 -- /tmp/portage/dev-python/cattrs-25.2.0/work/cattrs-25.2.0-pypy3_11/install/usr/bin/pypy3.11

[Tinche]

@mgorny Do you set the FAST env var when testing on PyPy? (

cattrs/tests/conftest.py

Line 31 in 727aa89

settings.load_profile("fast" if environ.get("FAST") == "1" else "tests")

)

[mgorny]

No, I don't. We actually have a local profile override for health checks, it wasn't active at the time — though since it was failing not due to timing, but apparently due to bad input, I've decided to file a bug.

[Tinche]

Some of the strategies are probably not implemented as efficiently as could be, so sometimes they complain about filtering too much. Pypy seems to be most susceptible.