Toju/toju-app/src/app/store/rooms/rooms-helpers-snapshot.spec.ts

import {
  reconcileRoomSnapshotChannels,
  sanitizeRoomSnapshot
} from './rooms.helpers';

describe('room snapshot helpers', () => {
  it('drops empty channel arrays from outgoing snapshots', () => {
    expect(sanitizeRoomSnapshot({ channels: [] }).channels).toBeUndefined();
  });

  it('keeps cached channels when incoming snapshot has none', () => {
    const cachedChannels = [
      { id: 'general', name: 'general', type: 'text', position: 0 },
      { id: 'updates', name: 'updates', type: 'text', position: 1 }
    ] as const;

    expect(reconcileRoomSnapshotChannels(cachedChannels as never, undefined)).toEqual(cachedChannels);
    expect(reconcileRoomSnapshotChannels(cachedChannels as never, [] as never)).toEqual(cachedChannels);
  });

  it('keeps richer cached channels when incoming snapshot is smaller', () => {
    const cachedChannels = [
      { id: 'general', name: 'general', type: 'text', position: 0 },
      { id: 'updates', name: 'updates', type: 'text', position: 1 },
      { id: 'voice', name: 'General', type: 'voice', position: 0 }
    ] as const;
    const incomingChannels = [
      { id: 'general', name: 'general', type: 'text', position: 0 }
    ] as const;

    expect(reconcileRoomSnapshotChannels(cachedChannels as never, incomingChannels as never)).toEqual(cachedChannels);
  });

  it('accepts incoming channels when snapshot is at least as complete', () => {
    const cachedChannels = [
      { id: 'general', name: 'general', type: 'text', position: 0 }
    ] as const;
    const incomingChannels = [
      { id: 'general', name: 'general', type: 'text', position: 0 },
      { id: 'updates', name: 'updates', type: 'text', position: 1 }
    ] as const;

    expect(reconcileRoomSnapshotChannels(cachedChannels as never, incomingChannels as never)).toEqual(incomingChannels);
  });
});