[Python] Hypothesis: test defensive programming

I'm writing tests with Hypothesis to test functions with restricted range. Consider the following toy example:

import math
from hypothesis import assume, example, given

def inc(value: float) -> float:
assert not math.isnan(value)
return value + 1

@given(st.floats())
def test_inc(value: float):
assume(not math.isnan(value))
if(value == math.inf or value == -math.inf):
assert inc(value) == value
else:
assert inc(value) > value


Here I'm testing the behaviour for finite and infinite inputs, but not NaN. I would like to test that out-of-range values, such as NaN, correctly throw an AssertionError.

Is there a pattern built into Hypothesis where I can test this? Ideally I'd like an approach where I don't compromise the coverage of within-range values.

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