AppReducer.js - Simple React + Redux example

AppReducer.js

const initialState = {
    count: 0
};

export default function AppReducer(state = initialState, action) {
    const newState = Object.assign({}, state);
    switch (action.type) {
        case 'INCREMENT':
            newState.count = newState.count + 1;
            return newState;
        case 'DECREMENT':
            newState.count = newState.count - 1;
            return newState;
        default:
            return state;
    }
}