Connector only checks state in shouldComponentUpdate about react-redux

[gaearon]

Can you please make a minimal reproducible example?

[gaearon]

To clarify,

Connect.prototype.shouldComponentUpdate = function shouldComponentUpdate(nextProps, nextState) {
     return !_utilsShallowEqual2['default'](this.state, nextState);
};

is not a problem. The props you pass will end up in connector's state, so we can only compare state.

[jptaylor]

Issue was that my deep object was still being referenced, correct reducer needed to be:

case constants.FORM_FIELD_UPDATE:
      _.set(state.values, action.keyPath, action.value);
      _.set(state.errors, action.keyPath, action.errors);
      return {
        ...state,
        values: {...state.values},
        errors: {...state.errors}
      };

Apologies for false alarm.

[gaearon]

This is not a correct solution, it just works around the problem. Don't use _.set if want immutability :-). That's just asking for trouble.

You are still mutating the state given to you. This is wrong. It happens to work, but it negates many benefits of Redux (support for DevTools, record/replay, etc). Do not do this.

[gaearon]

Your proposed solution only works one level deep. If you subscribe to state.form.values.something, it will break again. Please don't use _.set(). It's not the tool for the job.

Consider using something like https://github.com/substantial/updeep or Immutability Helpers instead of _.set. Otherwise you'll spend hours chasing weird bugs because _.set updated something deeply but there reference stayed the same.

[jptaylor]

Thank you @gaearon.