pydantic-core v2.29.0 introduced a bug with serialization that uses a wrapped serializer

[ornariece]

Initial Checks

• I confirm that I'm using Pydantic V2

Description

i also reported this in pydantic/pydantic-core#1651

import pydantic


class MyModel(pydantic.RootModel):
    root: str

    @pydantic.model_serializer(mode="wrap")
    def my_wrapper_serializer(self, serializer: pydantic.SerializerFunctionWrapHandler):
        return "my_prefix:" + serializer(self)


class MyParentModel(pydantic.BaseModel):
    nested: MyModel

    @pydantic.field_serializer('nested', mode="wrap")
    def wrapped_field_serializer(
        self, field_value, serializer: pydantic.SerializerFunctionWrapHandler
    ):
        return serializer(field_value)


if __name__ == "__main__":
    my_model = MyParentModel.model_validate({'nested': "validated_value"})

    print(my_model.model_dump())
    #>expected: {'nested': 'my_prefix:validated_value'}
    #>actual:   {'nested': 'my_prefix:my_prefix:validated_value'}

this didn't happen before the bump to pydantic-core 2.29.0.

Example Code

Python, Pydantic & OS Version

pydantic version: 2.11.0a1
        pydantic-core version: 2.29.0
          pydantic-core build: profile=release pgo=false
                 install path: C:\Users\me\AppData\Local\pypoetry\Cache\virtualenvs\myproject-py3.13\Lib\site-packages\pydantic
               python version: 3.13.0 (tags/v3.13.0:60403a5, Oct  7 2024, 09:38:07) [MSC v.1941 64 bit (AMD64)]
                     platform: Windows-10-10.0.19045-SP0
             related packages: mypy-1.15.0 typing_extensions-4.12.2
                       commit: unknown

[sydney-runkle]

Thanks for the report - we can confirm this bug and will fix for our beta release!

Looks like this is due to pydantic/pydantic-core#1616.