register_type_strategy doesn't work with lowercase builtin list type

[kasbah]

Using register_type_strategy doesn't seem to work with the built in list type available since python 3.9 (in fact typing.List is deprecated).

hypothesis==6.75.1
pytest==7.3.1
Python 3.10.10

from typing import get_args, Type, List
from hypothesis import strategies as st, given, infer


def _shorter_lists(list_type: Type) -> st.SearchStrategy:
    # doesn't get called unless using capital L List
    print("_shorter_lists called")
    sub_type = get_args(list_type)[0]
    return st.lists(st.from_type(sub_type), max_size=2)

# will make our test fail
st.register_type_strategy(list, _shorter_lists)

# will pass if uncommented, notice capital L
# st.register_type_strategy(List, _shorter_lists)


@given(infer)
def test_example(example: list[int]):
    assert len(example) <= 2

[Zac-HD]

--- a/hypothesis-python/src/hypothesis/strategies/_internal/types.py
+++ b/hypothesis-python/src/hypothesis/strategies/_internal/types.py
@@ -315,7 +315,8 @@ def is_generic_type(type_):
     # We check for `MyClass[T]` and `MyClass[int]` with the first condition,
     # while the second condition is for `MyClass`.
     return isinstance(type_, typing_root_type + (GenericAlias,)) or (
-        isinstance(type_, type) and typing.Generic in type_.__mro__
+        isinstance(type_, type)
+        and (typing.Generic in type_.__mro__ or hasattr(type_, "__class_getitem__"))
     )

This is enough to find the registered strategy for list... as well as for typing.List.

We'll need to do something to ensure that these are treated as a single lookup key, since resolving to different strategies for each will raise ResolutionFailed, but then I think it'll probably work? My main concern is that we'll be left with a more complicated user experience on Python < 3.9, when builtins aren't yet parametrizable.