How to use

SagaTester

in

redux-saga-tester

describe("root saga", () => {
 it("should handle 4 button clicks one after another", async () => {
  const sagaTester = new SagaTester({
   reducers: rootReducer
  });

  sagaTester.start(rootSaga);

  sagaTester.dispatch(queuedSagaAction());
  sagaTester.dispatch(queuedSagaAction());
  sagaTester.dispatch(queuedSagaAction());
  sagaTester.dispatch(queuedSagaAction());

  await delay(5000); // wait for 4 request * max 1sec each

  const state = sagaTester.getState();

  expect(state.exampleReducer.counter).toEqual(4);
 }, 30000);
});

test("filter saga", () => {
 const sagaTester = new SagaTester({
  initialState: {},
  reducers: {
   filter: filter,
   prices: prices,
  },
 });

 sagaTester.start(watchPeriod);

 sagaTester.dispatch(symbolSelected("S"));
 sagaTester.dispatch(periodSelected("W"));

 const state = sagaTester.getState();
 expect(state.filter).toEqual({
  period: "W",
  symbol: "S",
 });

 expect(state.prices.loading).toEqual(true);
});

test("search saga", async () => {
 const delay = (t) => new Promise((res) => setTimeout(() => res(), t));
 const sagaTester = new SagaTester({
  initialState: {},
  reducers: {
   search: search,
  },
 });

 const mockSuccessResponse = {
  bestMatches: [],
 };
 const mockJsonPromise = Promise.resolve(mockSuccessResponse);
 const mockFetchPromise = Promise.resolve({
  json: () => mockJsonPromise,
 });
 jest.spyOn(global, "fetch").mockImplementation(() => mockFetchPromise);

 sagaTester.start(watchSearch);

 sagaTester.dispatch(searchSymbol("S"));
 expect(global.fetch).toHaveBeenCalledTimes(1);

 await delay(0);
 expect(global.fetch).toHaveBeenCalledTimes(1);
 expect(sagaTester.getState().search.options).toEqual([]);
 expect(sagaTester.wasCalled(types.SYMBOL_FOUND)).toEqual(true);
});

test("prices saga", async () => {
 const delay = (t) => new Promise((res) => setTimeout(() => res(), t));
 const sagaTester = new SagaTester({
  initialState: {},
  reducers: {
   filter: filter,
   prices: prices,
  },
 });

 const mockSuccessResponse = {
  "Time Series": {},
 };
 const mockJsonPromise = Promise.resolve(mockSuccessResponse);
 const mockFetchPromise = Promise.resolve({
  json: () => mockJsonPromise,
 });
 jest.spyOn(global, "fetch").mockImplementation(() => mockFetchPromise);

 sagaTester.start(watchPrices);

 sagaTester.dispatch(fetchPrices());
 expect(sagaTester.getState().prices.loading).toEqual(true);
 expect(global.fetch).toHaveBeenCalledTimes(1);

 await delay(0);
 expect(global.fetch).toHaveBeenCalledTimes(1);
 expect(sagaTester.getState().prices.data.labels).toEqual([]);
 expect(sagaTester.wasCalled(types.PRICES_FETCHED)).toEqual(true);
});