How to update object using spread operator

Question

I am trying to update object using spread object, but not able to correctly update it. This is the result I want in first switch case:

{
  code: {
    loading: true
  }
}

And in second switch case, this is what I want:

{
  code : {
    loading: false,
    data: {
      some data here
    }
  }
}

const downloadData = (state = {}, action) => {
    switch (action.type) {
        case LOADING: {
            const {code, loading} = action.payload
            return {
                ...state,
                [code]: {
                    ...[code], loading
                }
            }
        }

        case LOADED: {
            const {code, loading, data} = action.payload
            return {
                ...state,
                [code] : {
                    loading, data, ...[code]
                }
            }
        }

        default: 
            return state
    }
}

Answer 1

I think your second case should be:

case LOADED: {
    const {code, loading, data} = action.payload
    return {
        ...state,
        code : {
            ...code,
            loading:false,
            data: {some data here}
        }
    }
}

Because the loading and data will overwrite the ...[code]

Answer 2

Assuming that you have initial state

const initialState = {
  code: {
    loading: false,
    data: {}
  }
};

For the first case try:

{
  ...state,
  code: {
    ...state.code,
    loading: true
  }
}

For second case:

{
  ...state,
      code: {
        ...state.code,
        loading: false,
        data: {
              some data here
              }
      }    
}