Function is

drizzle-orm/src/entity.ts:12–42

(value: any, type: T)

	& DrizzleEntity;

export function is<T extends DrizzleEntityClass<any>>(value: any, type: T): value is InstanceType<T> {
	if (!value || typeof value !== 'object') {
		return false;
	}

	if (value instanceof type) { // eslint-disable-line no-instanceof/no-instanceof
		return true;
	}

	if (!Object.prototype.hasOwnProperty.call(type, entityKind)) {
		throw new Error(
			`Class "${
				type.name ?? '<unknown>'
			}" doesn't look like a Drizzle entity. If this is incorrect and the class is provided by Drizzle, please report this as a bug.`,
		);
	}

	let cls = Object.getPrototypeOf(value).constructor;
	if (cls) {
		// Traverse the prototype chain to find the entityKind
		while (cls) {
			if (entityKind in cls && cls[entityKind] === type[entityKind]) {
				return true;
			}

			cls = Object.getPrototypeOf(cls);
		}
	}

	return false;
}