How to test root Epics

This is test original code.

// file: epics.js
import { combineEpics } from "redux-observable";
import { fooEpic, barEpic } from "./foo.js";
export default const epics = combineEpics(fooEpic, barEpic);

This is the Unit tesing

import { ActionsObservable } from "redux-observable";
import rootEpic from "./epics.js";
describe("Root epics", () => {
  it("should create proper epics", () => {
    const action$ = ActionsObservable.of({});
    expect(rootEpic(action$, null, {})).toMatchSnapshot();
  });
});

References