Learning Redux

Testing the setFilter action

After setting up our initial state, we can dispatch any actions by passing them to the reducer function:

1. We are going to write a test to ensure the setFilter action actually changes the filter. Edit __tests__/reducers/filter.test.js and add the following code:

test('setFilter action should change filter state', () => {

2. We start by creating the action object with the action creator:

  const category = 'test'  const action = setFilter(category)

3. Now, we call the reducer with the current state and our action, then save the new state:

  state = filterReducer(state, action)

4. Finally, we test if the state was changed to the category we set the filter to:

  expect(state).toBe(category)})