OptionalclassPer-window class resolver, consulted before defaultClass.
OptionalclockClock used for timestamps. Default: Date.now.
OptionaldefaultClass integer to assign when assign() gets no explicit value. Default 1.
OptionallatencyArtificial latency (ms) applied before each result. Default 0, which
responds synchronously inside handleMessage.
OptionalschedulerScheduler used for deferred pushes. Default: setTimeout.
OptionalseedSeed for deterministic ids and fixture ordering. Default 1.
Factory options for the class mock.
Example