Support multiple contract syntaxes about crosshair HOT 3 OPEN

You know what would be amazing? Symbolically executing tests written for Hypothesis! For example:

@given(st.integers(min_value=0))
def test(x):
    assert x ** 2 >= x

# could be equivalent to

def test(x: int):
    """pre: x >= 0"""
    assert x ** 2 >= x

this is particularly interesting to me because (a) I'm a core dev of Hypothesis 😜, (b) Hypothesis tests have to precisely describe the domain of valid inputs, and (c) they have a high density of assertions about error-prone behaviour!

I don't have time to write this myself (at least in the next few months), but would be delighted to help anyone who wants to have a go.

from crosshair.

An update: at present we support: PEP316, icontract, deal, an assert-based mode, and hypothesis. See these docs for details.

from crosshair.

Love this idea.

And it might not be all that difficult to do; the stuff we'd need to change is relatively well encapsulated in get_fn_conditions and get_class_conditions in condition_parser.py. There are some details to consider, however, like whether it's ok for exceptions can be thrown and what kind of copy happens for previous/old value comparisons. I think class invariants also have some subtle behaviors that might vary between contract implementations.

If someone wanted to make this happen for their favorite syntax, I would be completely happy to shepherd it along.

Otherwise, internet, please post or thumbs-up your favorite tools: with enough votes, I could probably prioritize some of my own time to try and get an implementation out.

from crosshair.