Tyoe for manual calss mocks

ManualClassMock.ts

type FunctionReturnTypes<T> = {
    [K in keyof T as T[K] extends Function ? K : never]:
    T[K] extends (...args: any) => infer R ? R : never
};

type ClassFieldsTypes<T> = {
    [K in keyof T]: T[K]
}

type ManualClassMock<T> = Partial<FunctionReturnTypes<T>> | Partial<ClassFieldsTypes<T>>;