Strategie from_type fails in some cases when using tuple instead of Tuple as type

[jldiaz]

There is a simple example:

from dataclasses import dataclass
from typing import Tuple
from hypothesis import given, strategies as st

@dataclass
class ItWorks:
    a: dict[Tuple[int, int], str]

@dataclass
class ItDoesnt:
    a: dict[tuple[int, int], str]

@given(st.from_type(ItWorks))
def test_works(x: ItWorks):
    assert len(x.a) >=0


@given(st.from_type(ItDoesnt))
def test_doesnt_work(x: ItDoesnt):
    assert len(x.a) >=0 

The difference between classes ItWorks and ItDoesnt is that the latter uses tuple instead of typing.Tuple. The first test passes, the second one produces the exception:

_______________________________________________ test_doesnt_work ______________________________________________

    @given(st.from_type(ItDoesnt))
>   def test_doesnt_work(x: ItDoesnt):

tests/test_demo.py:19: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
.venv/lib/python3.10/site-packages/hypothesis/core.py:568: in process_arguments_to_given
    search_strategy.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/collections.py:43: in do_validate
    s.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:821: in do_validate
    self.mapped_strategy.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/lazy.py:131: in do_validate
    w.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:821: in do_validate
    self.mapped_strategy.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/collections.py:43: in do_validate
    s.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/lazy.py:131: in do_validate
    w.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/core.py:871: in validate
    fixed_dictionaries(self.kwargs).validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/lazy.py:131: in do_validate
    w.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:821: in do_validate
    self.mapped_strategy.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/collections.py:43: in do_validate
    s.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:417: in validate
    self.do_validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/lazy.py:131: in do_validate
    w.validate()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:418: in validate
    self.is_empty
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:136: in accept
    recur(self)
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/strategies.py:132: in recur
    mapping[strat] = getattr(strat, calculation)(recur)
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/deferred.py:65: in calc_is_empty
    return recur(self.wrapped_strategy)
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/deferred.py:35: in wrapped_strategy
    result = self.__definition()
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/core.py:1047: in <lambda>
    lambda thing: deferred(lambda: _from_type(thing)),
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/core.py:1167: in _from_type
    return types.from_typing_type(thing)
.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/types.py:425: in from_typing_type
    if not any(
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
.0 = <list_iterator object at 0x7f017187cfd0>

    if not any(
>       isinstance(T, type) and issubclass(int, T)
        for T in list(union_elems) + [elem_type]
    ):
E   TypeError: issubclass() argument 2 cannot be a parameterized generic

.venv/lib/python3.10/site-packages/hypothesis/strategies/_internal/types.py:426: TypeError

Since it is now recommended to use directly the non-typing generic vs the typing.Tuple type, this is a problem.

Note. This happens apparently only when the tuple is used as key in a dict.

[nicksspirit]

Alright I got this!!

[Zac-HD]

Both work on hypothesis version 6.77.0 (Python 3.10.11), so I'm assuming that this has been fixed and closing. If you can reproduce, please let us know and we'll re-open the issue!