socket_hub_testing library

Test doubles for socket_hub: a socket with no network behind it, and a stand-in server that answers what a hub subscribes to.

Import this in tests, and in a mock mode where the real backend is not available. Neither piece is needed in production, so keeping them in a second library keeps them out of a release build's tree-shaken output.

final server = MockSocketServer(
  build: (key, tick) => {'symbol': key.args['symbol'], 'last': 100 + tick},
  tick: const Duration(days: 1),        // driven by pump(), not a clock
);
final hub = SocketChannelHub<Object?>(transport: server.open, codec: codec);

final ticks = <Object?>[];
hub.stream(SubscriptionKey('ticker', {'symbol': 'BTC'})).listen(ticks.add);
await hub.whenReady();
server.pump();

Classes

FakeTransport

A SocketTransport with no socket behind it, for tests and mock modes.

MockSocketServer

A stand-in server: it reads the subscribe frames a hub sends and pushes generated payloads back for whatever is subscribed.

Typedefs

MockPayloadBuilder = Object? Function(SubscriptionKey key, int tick)

Builds the payload for one subscription on one tick.