ValidationError when converting Decimal('10000000000000000000') to int

[gmagno]

Initial Checks

• I confirm that I'm using Pydantic V2

Description

Hello 👋 🤓

Pydantic throws a ValidationError when converting a Decimal of an int to int. Not sure if this is the expected behavior.

from decimal import Decimal
from pydantic import BaseModel

class A(BaseModel):
    a: int

A(a=10000000000000000000)  # this works

A(a=Decimal('10000000000000000000'))  # this doesn't

ValidationError: 1 validation error for A
a
  Unable to parse input string as an integer, exceeded maximum size [type=int_parsing_size, input_value=Decimal('10000000000000000000'), input_type=Decimal]
    For further information visit https://errors.pydantic.dev/2.3/v/int_parsing_size

Example Code

from decimal import Decimal
from pydantic import BaseModel

class A(BaseModel):
    a: int

A(a=Decimal('10000000000000000000'))

Python, Pydantic & OS Version

pydantic version: 2.3.0
  pydantic-core version: 2.6.3
    pydantic-core build: profile=release pgo=true
            install path: ****/.venv/lib/python3.10/site-packages/pydantic
          python version: 3.10.12 (main, Jun 11 2023, 05:26:28) [GCC 11.4.0]
                platform: Linux-5.19.0-50-generic-x86_64-with-glibc2.35
optional deps. installed: ['typing-extensions']

Selected Assignee: @lig

[adriangb]

It looks like what's happening here is that the Decimal is getting converted to a float first and then trying to be pushed into a float64. We'll need to fix this on the pydantic-core side.

[adriangb]

This will be fixed in the next release. Thank you for reporting it!

[gmagno]

Thank you @adriangb, you guys are amazing ❤️