How add new field into reducer using Immer.js?

Question

For example,

state = {
  data: {}
}

How can I add a new nested field into an object? I cannot set that field, because have an error Cannot read property 'date' of undefined

const reducer = produce((draft, action) => {
   switch (action.type) {
      case 'ACTION_SUCCESS':
      draft.data.children.date = action.response;
   }
});

As a result I want:

  data: {
     children: {
        data: 'date'
     }
  }
}

score 1 · Answer 1 · answered Apr 15 '21 at 15:20

1

Normal JS object manipulation rules apply here. You can't write obj.x.y.z = if there is no .y field yet - you have to create that first.

answered Apr 15 '21 at 15:20

markerikson

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What is the best way to create a new field in an object? – Liudmyla Apr 16 '21 at 06:55
Like I said, it's just normal JS from your code's perspective. So, something like `someObj.newField = 123`. – markerikson Apr 16 '21 at 17:00

How add new field into reducer using Immer.js?

1 Answers1