Initial Checks
Description
The recently released typing extensions 4.12.0 causes issues with models with a field containing an annotated list of discriminated unions.
With typing extensions less than 4.12 it works fine:
$ pip list | grep typing_extensions
typing_extensions 4.11.0
$ python test.py
items=[MyItemA(item_type='a', things=[1, 2, 3]), MyItemB(item_type='b', thing=4)]
With 4.12.0 it fails:
$ pip list | grep typing_extensions
typing_extensions 4.12.0
$ python test.py
Traceback (most recent call last):
File "/build/test.py", line 16, in <module>
class MyModel(BaseModel):
File "/build/test.py", line 17, in MyModel
items: Annotated[
^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 2090, in __class_getitem__
return cls._class_getitem_inner(cls, *params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 398, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 2104, in _class_getitem_inner
return _AnnotatedAlias(origin, metadata)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 1997, in __init__
super().__init__(origin, origin, name='Annotated')
File "/usr/local/lib/python3.12/typing.py", line 1248, in __init__
self.__parameters__ = _collect_parameters(args)
^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/typing_extensions.py", line 3028, in _collect_parameters
enforce_default_ordering = _has_generic_or_protocol_as_origin()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/typing_extensions.py", line 2955, in _has_generic_or_protocol_as_origin
return frame.f_locals.get("origin") in {
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/typing.py", line 2023, in __hash__
return hash((self.__origin__, self.__metadata__))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<string>", line 3, in __hash__
TypeError: unhashable type: 'dict'
Note that if I remove either the inner Discriminator annotation or the outer Len annotation it works.
Example Code
from typing import Annotated, Literal
from annotated_types import Len
from pydantic import BaseModel, Field, Discriminator
class MyItemA(BaseModel):
item_type: Literal["a"] = "a"
things: list[int]
class MyItemB(BaseModel):
item_type: Literal["b"] = "b"
thing: int
class MyModel(BaseModel):
items: Annotated[
list[
Annotated[
MyItemA | MyItemB,
Discriminator(
discriminator="item_type",
custom_error_type="invalid_union_member",
custom_error_message="Invalid union member",
custom_error_context={"discriminator": "item_type"},
),
]
],
Len(min_length=1),
]
print(
MyModel.model_validate(
{
"items": [
{"item_type": "a", "things": [1, 2, 3]},
{"item_type": "b", "thing": 4},
]
}
)
)Python, Pydantic & OS Version
pydantic version: 2.7.1
pydantic-core version: 2.18.2
pydantic-core build: profile=release pgo=true
install path: /usr/local/lib/python3.12/site-packages/pydantic
python version: 3.12.3 (main, May 14 2024, 07:23:41) [GCC 12.2.0]
platform: Linux-6.5.0-35-generic-x86_64-with-glibc2.36
related packages: typing_extensions-4.12.0 mypy-1.10.0 pydantic-settings-2.2.1
commit: unknown
Initial Checks
Description
The recently released typing extensions 4.12.0 causes issues with models with a field containing an annotated list of discriminated unions.
With typing extensions less than 4.12 it works fine:
With 4.12.0 it fails:
Note that if I remove either the inner Discriminator annotation or the outer Len annotation it works.
Example Code
Python, Pydantic & OS Version