reviews-of-the-week.js

  filterByBrand = event => {
    this.setState({ brand: event.target.value }, () => {
      const filtered = this.state.items.filter(item =>
        item.manufacturer.toLowerCase()
        .includes(this.state.brand.toLowerCase()),
      );
      this.setState({ filtered });
    });
  };
  
  filterByRating = event => {
    this.setState({ rating: event.target.value.slice(0, 1) }, () => {
      const filtered = this.state.items.filter(item => 
         item.rating >= this.state.rating);
      this.setState({ filtered });
    });
  };