rxjs-marbles
By Nicholas Jamieson • Added May 22, 2020 • 
rxjs-marbles is an RxJS marble testing library that should be compatible with any test framework. It wraps the RxJS TestScheduler and provides methods similar to the helper methods used the TestScheduler API.
It can be used with AVA, Jasmine, Jest, Mocha or Tape in the browser or in Node and it supports CommonJS and ES module bundlers.