[BUG]: Kyselify not supporting snake_case casing

[johanneskares]

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What version of drizzle-orm are you using?

0.39.0

What version of drizzle-kit are you using?

0.30.3

Other packages

No response

Describe the Bug

When using

import type { Kyselify } from "drizzle-orm/kysely";

the casing option of snake_case is not supported. Here's my workaround that should be included in the Kyselify file.

type CamelToSnake<S extends string> = S extends `${infer T}${infer U}`
    ? `${T extends Lowercase<T> ? T : `_${Lowercase<T>}`}${CamelToSnake<U>}`
    : S;

type ConvertKeysToSnakeCase<T> = {
    [K in keyof T as CamelToSnake<Extract<K, string>>]: T[K];
};

type KyselifyCased<
    T extends Table,
    Casing extends "camelCase" | "snake_case" = "camelCase",
> = Casing extends "camelCase" ? Kyselify<T> : ConvertKeysToSnakeCase<Kyselify<T>>;

Can be used like

interface Database {
    token: KyselifyCased<typeof token, "snake_case">;
    user: KyselifyCased<typeof user, "snake_case">;
}

const result = await kysely.selectFrom("token").select(["id", "created_at"]).execute();