Typing error: Incompatible types in assignment (expression has type "ConfigDict", base class "SQLModel" defined the type as "SQLModelConfig")

[copdips]

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Example Code

from pydantic import ConfigDict

class HeroCreate(SQLModel):
    name: str | None = None

    class Config:
        extra = "forbid"

class HeroUpdate(SQLModel):
    name: str | None = None
    model_config = ConfigDict(extra="forbid")

Description

Hello,

I need to add a config to prevent from extra fields when creating or updating Hero model.

Above example works well, but my VSCode raises linting errors

When using:

    class Config:
        extra = "forbid"

The linting error thrown by Pylance is:

"Config" overrides symbol of same name in class "SQLModel"
  "app.db.models.HeroCreate.Config" is incompatible with "sqlmodel.main.SQLModel.Config"
  Type "type[app.db.models.HeroCreate.Config]" cannot be assigned to type "type[sqlmodel.main.SQLModel.Config]"

When using the second format:

model_config: ConfigDict = ConfigDict(extra="forbid")

The linting error thrown by MyPy is:

Incompatible types in assignment (expression has type "ConfigDict", base class "SQLModel" defined the type as "SQLModelConfig")

Operating System

Linux

Operating System Details

No response

SQLModel Version

lastest: 0.0.16

Python Version

3.11.7

Additional Context

mypy 1.9.0
mypy-extensions 1.0.0

[SantiMNV]

I experience the same, any updates on this?

[joachimhuet]

It looks like SQLModelConfig still inherits the deprecated BaseConfig class. sqlmodel._compat.py.
If you change BaseConfig parent class with pydantic.ConfigDict does your warning remains ?

[copdips]

It seems that it uses already pydantic.ConfigDict:
https://github.com/tiangolo/sqlmodel/blob/6151f23e15703223128d641081b63d49a658d524/sqlmodel/_compat.py#L72-L73

[joachimhuet]

Oh yes you are right, it seems my editor point to the else condition by default. Probably mypy does not know where to look at neither.

I tried to reproduce and i get rid of the warning by doing that:

from sqlmodel._compat import SQLModelConfig

class BaseModel(SQLModel):
    model_config = cast(SQLModelConfig, {"extra": "forbid"})

But I'm not sure it is a good idea, just putting a # type: ignore would also safely work by passing a dict to model_config

class BaseModel(SQLModel):
    model_config = {"extra": "forbid"}  # type: ignore

[copdips]

if we were to accept # type: ignore, I would then add it directly to model_config = ConfigDict(extra="forbid")

[zwlxt]

My workaround is creating a BaseModel which inherits your customized pydantic.BaseModel and SQLModel. It seems to satisfy pylance (in strict mode).

I am using sqlmodel==0.0.24 and Python 3.13.3

class CamelCasedModel(pydantic.BaseModel):
    model_config = ConfigDict(
        alias_generator=to_camel,
        populate_by_name=True,
    )

# note: first CamelCasedModel then SQLModel
class BaseModel(CamelCasedModel, SQLModel):
    pass

# then use it in your entity class
class UserAccount(BaseModel, table=True):
    ...

[natehouk]

Any update on this?

[aemonge]

No update?

[bartelemi]

Seems like this is still a problem even on v0.0.23 and v0.0.24 of sqlmodel and pydantic v2.
There were some small changes in how the IS_PYDANTIC_V2 typing guard is constructed, but mypy is still struggling to understand it and defaults to the else: statement (thinking that the code is running pydantic v1).