I am testing my redux-saga-flow, and I have an issue with testing selector method with select.
Selector
const selector = (state) => {
console.log("selector");
return data;
}
Redux saga flow
export function* testedSagaFlow() {
const data = yield select(selector);
if (!data) {
return;
}
yield put (otherAction)
...
}
Test for flow
test("Get data from store", () => {
return expectSaga(testedSagaFlow)
.provide([[mathchers.select.selector(selector), null]])
.select(selector)
.not.put(otherAction)
.run()
})
After running a test, a do not have console.log("selector"); and also this line of code did not covered by test.
How can I test a selectors?
The same does not work with unit test.
test("Unit test flow", () => {
const saga = testSaga(testedSagaFlow);
saga
.next()
.select(selector)
.next(null)
.isDone()
})
"redux-saga-test-plan": "^4.0.1".
Option 1. Use withState:
For static state, you can just use the
withStatemethod to allowselecteffects to work.
Option 2. Use static provider
You can provide mock values in a terse manner via static providers. Pass in an array of tuple pairs (array pairs) into the
providemethod. For each pair, the first element should be a matcher for matching the effect and the second effect should be the mock value you want to provide.
E.g.
saga.ts:
import { put, select } from 'redux-saga/effects';
const otherAction = { type: 'OTHER_ACTION' };
export const selector = (state) => {
console.log('selector');
return state.data;
};
export function* testedSagaFlow() {
const data = yield select(selector);
if (!data) {
return;
}
yield put(otherAction);
}
saga.test.ts:
import { expectSaga } from 'redux-saga-test-plan';
import { select } from 'redux-saga/effects';
import { selector, testedSagaFlow } from './saga';
describe('70199170', () => {
test('should dispatch other action', () => {
const state = { data: true };
return expectSaga(testedSagaFlow).withState(state).put({ type: 'OTHER_ACTION' }).run();
});
test('should return if data is nil', () => {
const state = { data: null };
return expectSaga(testedSagaFlow).withState(state).not.put({ type: 'OTHER_ACTION' }).run();
});
});
describe('70199170 - use provider', () => {
test('should dispatch other action', () => {
return expectSaga(testedSagaFlow)
.provide([[select(selector), true]])
.put({ type: 'OTHER_ACTION' })
.run();
});
test('should return if data is nil', () => {
return expectSaga(testedSagaFlow)
.provide([[select(selector), null]])
.not.put({ type: 'OTHER_ACTION' })
.run();
});
});
Test result:
PASS redux-saga-examples packages/redux-saga-examples/src/stackoverflow/70199170/saga.test.ts
70199170
✓ should dispatch other action (30 ms)
✓ should return if data is nil (4 ms)
70199170 - use provider
✓ should dispatch other action (2 ms)
✓ should return if data is nil (3 ms)
console.log
selector
at selector (packages/redux-saga-examples/src/stackoverflow/70199170/saga.ts:6:11)
console.log
selector
at selector (packages/redux-saga-examples/src/stackoverflow/70199170/saga.ts:6:11)
Test Suites: 1 passed, 1 total
Tests: 4 passed, 4 total
Snapshots: 0 total
Time: 2.934 s, estimated 3 s
Ran all test suites related to changed files.