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Not working list[str] field

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
38/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
api

Research direction

Start by running tmp.conao3/04_list.sample.py with poetry run python tmp.conao3/04_list.sample.py to reproduce the failure while defining GrapheneModel. Trace how the list[str] field is converted and ensure the schema can be created and {model {field}} executes without the mutable-default error.

Written by the indexing model from the issue text.

Description

I found graphene-pydantic fails converting list[str] field.

import graphene
import pydantic

import graphene_pydantic


class Model(pydantic.BaseModel):
    field: list[str] = []


class GrapheneModel(graphene_pydantic.PydanticObjectType):
    class Meta:
        model = Model


class Query(graphene.ObjectType):
    model = graphene.Field(GrapheneModel)
    hello = graphene.String()

    @staticmethod
    def resolve_model(parent, info):
        return Model()


schema = graphene.Schema(query=Query)
print(schema)
print(schema.execute('{model {field}}'))

saved as tmp.conao3/04_list.sample.py and run like this

$ poetry run python tmp.conao3/04_list.sample.py

then, you see error.

Traceback (most recent call last):
  File "/home/conao/dev/forks/graphene-pydantic/tmp.conao3/04_list.sample.py", line 11, in <module>
    class GrapheneModel(graphene_pydantic.PydanticObjectType):
  File "/home/conao/dev/forks/graphene-pydantic/.venv/lib/python3.10/site-packages/graphene/types/objecttype.py", line 45, in __new__
    dataclass = make_dataclass(name_, fields, bases=())
  File "/usr/lib/python3.10/dataclasses.py", line 1401, in make_dataclass
    return dataclass(cls, init=init, repr=repr, eq=eq, order=order,
  File "/usr/lib/python3.10/dataclasses.py", line 1185, in dataclass
    return wrap(cls)
  File "/usr/lib/python3.10/dataclasses.py", line 1176, in wrap
    return _process_class(cls, init, repr, eq, order, unsafe_hash,
  File "/usr/lib/python3.10/dataclasses.py", line 956, in _process_class
    cls_fields.append(_get_field(cls, name, type, kw_only))
  File "/usr/lib/python3.10/dataclasses.py", line 813, in _get_field
    raise ValueError(f'mutable default {type(f.default)} for field '
ValueError: mutable default <class 'list'> for field field is not allowed: use default_factory

I use now main(2fd67a8) and I use Python3.10

Dominant language
Python
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Forks
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