def test_mutually_recursive_types_with_typevar(data):
# The previously-failing example from the issue
A = Dict[str, "B"] # noqa: F821 - an undefined name is the whole point!
B = Union[List[str], A]
with pytest.raises(ResolutionFailed,
match=r"Could not resolve ForwardRef\('B'\)"):
data.draw(st.from_type(A))
with utils.temp_registered(
ForwardRef("B"),
lambda _: st.deferred(lambda: b_strategy),
):
b_strategy = st.from_type(B)
data.draw(b_strategy)
data.draw(st.from_type(A))
data.draw(st.from_type(B))
def test_mutually_recursive_types_with_typevar_alternate(data):
# It's not particularly clear why this version passed when the previous
# test failed, but different behaviour means we add both to the suite.
C = Union[List[str],
"D"] # noqa: F821 - an undefined name is the whole point!
D = Dict[str, C]
with pytest.raises(ResolutionFailed,
match=r"Could not resolve ForwardRef\('D'\)"):
data.draw(st.from_type(C))
with utils.temp_registered(
ForwardRef("D"),
lambda _: st.deferred(lambda: d_strategy),
):
d_strategy = st.from_type(D)
data.draw(d_strategy)
data.draw(st.from_type(C))
data.draw(st.from_type(D))
def test_bound_type_cheking_only_forward_ref_wrong_type():
"""We should check ``ForwardRef`` parameter name correctly."""
with utils.temp_registered(ForwardRef("WrongType"), st.just(1)):
with pytest.raises(ResolutionFailed):
st.builds(typechecking_only_fun).example()
def test_bound_type_cheking_only_forward_ref():
"""We should fallback to registering explicit ``ForwardRef`` when we have to."""
with utils.temp_registered(ForwardRef("ExcInfo"), st.just(1)):
st.builds(typechecking_only_fun).example()