Tuple field triggers error checking inheritance

[asmodehn]

Checks

• I added a descriptive title to this issue
• I have searched (google, github) for similar issues and couldn't find anything
• I have read and followed the docs and still think this is a bug

Bug

Output of python -c "import pydantic.utils; print(pydantic.utils.version_info())":

             pydantic version: 1.7.2
            pydantic compiled: True
                 install path: /home/alexv/.local/share/virtualenvs/datacrystals-F4r2dbjD/lib/python3.8/site-packages/pydantic
               python version: 3.8.2 (default, Apr 27 2020, 15:53:34)  [GCC 9.3.0]
                     platform: Linux-5.4.0-7634-generic-x86_64-with-glibc2.29
     optional deps. installed: ['typing-extensions']

I didn't yet investigate what is happening here, but this looks like something that should be working...

from pydantic.dataclasses import dataclass
import typing
@dataclass
class wrappingTuple:
    field: typing.Tuple

print(wrappingTuple(field=(0,1))

triggers :

Traceback (most recent call last):
  File "pydantic/validators.py", line 615, in pydantic.validators.find_validators
TypeError: issubclass() arg 1 must be a class
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "<input>", line 2, in <module>
  File "pydantic/dataclasses.py", line 216, in pydantic.dataclasses.dataclass
  File "pydantic/dataclasses.py", line 211, in pydantic.dataclasses.dataclass.wrap
  File "pydantic/dataclasses.py", line 147, in pydantic.dataclasses._process_class
  File "pydantic/main.py", line 925, in pydantic.main.create_model
  File "pydantic/main.py", line 262, in pydantic.main.ModelMetaclass.__new__
  File "pydantic/fields.py", line 315, in pydantic.fields.ModelField.infer
  File "pydantic/fields.py", line 284, in pydantic.fields.ModelField.__init__
  File "pydantic/fields.py", line 362, in pydantic.fields.ModelField.prepare
  File "pydantic/fields.py", line 538, in pydantic.fields.ModelField.populate_validators
  File "pydantic/validators.py", line 624, in find_validators
RuntimeError: error checking inheritance of typing.Tuple (type: Tuple)

However this works fine :

from pydantic.dataclasses import dataclass
import typing
@dataclass
class wrappingTuple:
    field: tuple

print(wrappingTuple(field=(0,1))

wrappingTuple(field=(0, 1))

and this as well :

from pydantic.dataclasses import dataclass
import typing
@dataclass
class wrappingTuple:
    field: typing.List

print(wrappingTuple(field=[0,1])

wrappingTuple(field=[0, 1])

[PrettyWood]

Hi @asmodehn
Thanks for reporting!
You're absolutely right it should work! I just made a quick PR to fix this behaviour.
You're welcome to try it out :)
Cheers

[dannyrohde]

Quick question. Is it possible that an issue that I'm facing is similar to this one? Please let me know or if I should open a separate bug report.

This works:
from typing import List
finance_events: List["FinanceEventsOrder"] = Relationship(back_populates="order", sa_relationship_kwargs={"cascade": "all, delete-orphan"})

This doesn't work:
finance_events: list["FinanceEventsOrder"] = Relationship(back_populates="order", sa_relationship_kwargs={"cascade": "all, delete-orphan"})

I'm on Python 3.9, so I assumed that 'list' instead or 'typing.List' would work.

[bellebethcooper]

I've found the same issue as @dannyrohde on Python 3.10. I'm using pydantic 1.9.0, and the workaround of importing List from typing works for me.

[igorkf]

Same issue here.
Upgrading from 1.7 to 1.9.0 solved the problem.