re-reselect | Enhance Reselect selectors with deeper memoization | Caching library

You are creating a new array on every mapStateToProps call with myArray: [0, 1, 2]. Because of this, mapStateToProps always returns an object with a new instance of an array.

Redux than does a shallow comparison of the previous props. The references of myArray changed, since oyu created a new one during the call and all cells get udpated. By removing the myArray: [0, 1, 2] line, it works as expected. Move that array into redux, so that you do not generate a new one of every call.

The pure component is also useless, since redux already does a prop comparison and the pure component does the same thing again, so that is wasted since it always has the same result for redux and the pure component and is just more work.

Update: You are still creating a new array on every mapSateToPropsCall with the map function in getMyArray, since map returns a new array. Why do you not make the array static or memoize that, so that you only generate a new one, if needed?

Why do you not change how you save the data so that state.myArray[index] returns the needed array?

And you still can transform the PureCompoennt to Component.