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jfairbank / redux-saga-test-plan

Test Redux Saga with an easy plan.
http://redux-saga-test-plan.jeremyfairbank.com
MIT License
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Use of a non-generator function as the callback to takeEvery results in: TypeError: Cannot read properties of undefined (reading 'next') #391

Open JackStandbridgeCS opened 8 months ago

JackStandbridgeCS commented 8 months ago

Summary

When a takeEvery has a non-generator function as the second argument, the saga runs fine in the application, but errors when it is run by redux-saga-test-plan's expectSaga.

Expected behaviour

There is no error in the test when there is no error in the application code.

Actual behaviour

This error is printed in the terminal:

TypeError: Cannot read properties of undefined (reading 'next')
    at getNext (project/node_modules/redux-saga-test-plan/lib/expectSaga/sagaWrapper.js:51:32)
    at Object.INIT (project/node_modules/redux-saga-test-plan/lib/expectSaga/sagaWrapper.js:74:18)
    at Object.next (project/node_modules/fsm-iterator/lib/index.js:91:37)
    at next (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:1161:27)
    at proc (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:1112:3)
    at project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:589:17
    at immediately (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:60:12)
    at runForkEffect (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:588:3)
    at runEffect (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:1208:7)
    at digestEffect (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:1275:5)
    at next (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:1165:9)
    at currCb (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:1255:7)
    at takeCb (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:507:5)
    at put (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:343:9)
    at project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:380:7
    at exec (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:35:5)
    at flush (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:91:5)
    at asap (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:50:5)
    at Object.chan.put (project/node_modules/@redux-saga/core/dist/redux-saga-core.dev.cjs.js:379:5)
    at notifyListeners (project/node_modules/redux-saga-test-plan/lib/expectSaga/index.js:327:15)
    at project/node_modules/redux-saga-test-plan/lib/expectSaga/index.js:341:34
    at processTicksAndRejections (node:internal/process/task_queues:96:5)

Reproduction

import { expectSaga } from "redux-saga-test-plan";
import { takeEvery } from "redux-saga/effects";

const repro = function* () {
  yield takeEvery("action", () => {});
};

describe(repro, () => {
  it("should not error", () => {
    return expectSaga(repro).dispatch({ type: "action" }).silentRun(0);
  });
});

Updating the takeEvery to yield takeEvery("action", function* () {}); causes the error to go away, however, both the generator and non-generator versions work when running in my application.

Dependencies

These are the versions I have in the project:

    "redux-saga": "1.2.3",
    "redux-saga-test-plan": "4.0.6",

And I'm running the tests with node v16.15.0