shouldComponentUpdate = (nextProps, nextState) => {
        const { shops } = nextState;

        // current and next shops lengths
        const currentLength = this.state.shops.length;
        const nextLength = nextState.shops.length;
        return (currentLength === nextLength && !this._shopsHasSelectedShop(shops)) || currentLength !== nextLength;
    };

    _shopsHasSelectedShop = (shops) => {
        return shops.some(shop => shop.id === this.state.selectedShopID);
    };