José Almeida
12 lines
535 B
TypeScript
12 lines
535 B
TypeScript
export type ArrivalSnapshot = { sessionId: string | null; ids: readonly string[]; live: boolean };
|
|
|
|
/** Only appends to an already visible, reconciled transcript are entrances. */
|
|
export function getNewArrivalIds(
|
|
previous: ArrivalSnapshot | null,
|
|
next: ArrivalSnapshot,
|
|
): ReadonlySet<string> {
|
|
if (!previous?.live || !next.live || previous.sessionId !== next.sessionId) return new Set();
|
|
if (previous.ids.some((id, index) => next.ids[index] !== id)) return new Set();
|
|
return new Set(next.ids.slice(previous.ids.length));
|
|
}
|