[Bug]: env_nested_delimiter Is Not Implemented

[FatJun]

Description

env_nested_delimiter Is Not Implemented in code base

Steps to Reproduce

1. Install msgspec-ext
2. Try to use env_nested_delimiter from readme and docs
3. Get shocked
4. Go to source and make sure that env_nested_delimiter is not implemented
5. Open an issue on GitHub

Expected Behavior

To Be Implemented

Actual Behavior

Not To Be Implemented

Code Example

from functools import cache, cached_property
from typing import Literal, Self
from urllib.parse import quote, urlunsplit

from msgspec_ext import (
    BaseSettings,
    SecretStr,
    SettingsConfigDict,
)

type _Scheme = Literal["postgresql", "postgresql+asyncpg"]

class PostgresConnection(BaseSettings):
    username: SecretStr
    password: SecretStr
    host: SecretStr
    port: int
    db: SecretStr

    @cached_property
    def adsn(self) -> str:
        return self._build_dsn("postgresql+asyncpg")

    @cached_property
    def dsn(self) -> str:
        return self._build_dsn("postgresql")

    def _build_dsn(self, scheme: str) -> str:
        userinfo = f"{quote(self.username)}:{quote(self.password)}"
        netloc = f"{userinfo}@{self.host}:{self.port}"
        return urlunsplit((scheme, netloc, self.db, "", ""))


class DatabaseConnections(BaseSettings):
    postgres: PostgresConnection


class AppSettings(BaseSettings):
    model_config = SettingsConfigDict(
        env_file=".env",
        env_nested_delimiter="__",
    )

    database: DatabaseConnections

    @classmethod
    @cache
    def get_settings(cls) -> Self:
        return cls()

msgspec-ext Version

0.5.0

Python Version

3.13

Operating System

Windows 11

Additional Context

No response

[vilsonrodrigues]

Thank you for detecting the bug. I will review your PR.

[vilsonrodrigues]

Resolved in #49