searchFormReducer.js

const initialState = // initial state;

module.exports = (state = initialState, action) => {
  switch (action.type) {
    case FILTER_UPDATED: // return new state containing the updated filter value
    case FILTERS_CLEARED: // return new state reset to initial value   
    case TAB_SWITCHED: // return new state containing the location filter value from previous tab
    case FILTERS_ROUTED: // return new state containing user's most recent location search  
    case SEARCH_HISTORY_ITEM_SELECTED: // set the state to the selected item from search history 
    default: return state;
  }
};