woocommerce/plugins/woocommerce-blocks/assets/js/data/cart/reducers.js

/**
 * Internal dependencies
 */
import { ACTION_TYPES as types } from './action-types';

/**
 * Reducer for receiving items related to the cart.
 *
 * @param   {Object}  state   The current state in the store.
 * @param   {Object}  action  Action object.
 *
 * @return  {Object}          New or existing state.
 */
const reducer = (
	state = {
		cartData: {
			coupons: [],
			items: [],
			itemsCount: 0,
			itemsWeight: 0,
			needsShipping: true,
			totals: {},
		},
		metaData: {},
		errors: [],
	},
	action
) => {
	switch ( action.type ) {
		case types.RECEIVE_ERROR:
			state = {
				...state,
				errors: state.errors.concat( action.error ),
			};
			break;
		case types.REPLACE_ERRORS:
			state = {
				...state,
				errors: [ action.error ],
			};
			break;
		case types.RECEIVE_CART:
			state = {
				...state,
				errors: [],
				cartData: action.response,
			};
			break;
		case types.APPLYING_COUPON:
			state = {
				...state,
				metaData: {
					...state.metaData,
					applyingCoupon: action.couponCode,
				},
			};
			break;
		case types.REMOVING_COUPON:
			state = {
				...state,
				metaData: {
					...state.metaData,
					removingCoupon: action.couponCode,
				},
			};
			break;
	}
	return state;
};

export default reducer;