Type Alias RequireOnlyOne<T, Keys>

RequireOnlyOne: Pick<T, Exclude<keyof T, Keys>> & {
    [K in Keys]-?: Required<Pick<T, K>> & Partial<
        Record<Exclude<Keys, K>, undefined>,
    >
}[Keys]

Makes a type such that only one of the provided properties is required. RequireOnlyOne<someType, 'prop1'|'prop2'>