Im getting a undefined error on line 37. Please help

const menu = {
  _courses: {
    appetizers: [],
    mains: [],
    desserts: [],
  },
  get appetizers(){
    this._courses.appetizers;
  },
  get mains(){
    this._courses.mains;
  },
  get desserts(){
    this._courses.desserts;
  },
  set appetizers(appetizers){
    this._courses.appetizers = appetizers;
  },
  set mains(mains){
    this._courses.mains = mains;
  },
  set desserts(desserts){
    this._courses.desserts = desserts;
  },
  get _course(){
    return {
      appetizers: this.appetizers,
      mains: this.mains,
      desserts: this.desserts
    };
  },
  addDishToCourse(courseName, dishName, dishPrice){
    const dish = {
      name: dishName,
      price: dishPrice,
    };
    return this._courses[courseName].push(dish);
  },
  getRandomDishFromCourse(courseName){
    const dishes = this._courses[courseName];
    const randomIndex = Math.floor(Math.random() * dishes.length);
    return dishes[randomIndex];
  },
  generateRandomMeal(){
    const appetizer = this.getRandomDishFromCourse('appetizers');
    const main = this.getRandomDishFromCourse('mains');
    const dessert = this.getRandomDishFromCourse('desserts');
    const cost = appetizer.price + main.price + dessert.price;
    return `Your meal is ${appetizer.name},
     ${main.name}, and ${dessert.name} and total price is ${cost}`;
  }
};

menu.addDishToCourse('appetizers', 'wings', 4.00);
menu.addDishToCourse('appetizers', 'tacos', 4.00);
menu.addDishToCourse('appetizers', 'salad', 4.00);

menu.addDishToCourse('mains', 'steak', 10.00);
menu.addDishToCourse('mains', 'fish', 10.00);
menu.addDishToCourse('mains', 'pasta', 10.00);

menu.addDishToCourse('dessert', 'cake', 6.00);
menu.addDishToCourse('dessert', 'shake', 6.00);
menu.addDishToCourse('dessert', 'pie', 6.00);

let meal = menu.generateRandomMeal();
console.log(meal);

then the first question is: What results in undefined? We get undefined when we try to look-up/access a property/key on an object which does not exists, so then the first step to debug would be to:

  1. log available keys/properties
  2. log keys/properties you attempt to use

so we insert a .log():

  addDishToCourse(courseName, dishName, dishPrice){
    const dish = {
      name: dishName,
      price: dishPrice,
    };
    
    console.log(Object.keys(this._courses), courseName);
    return this._courses[courseName].push(dish);
  },

I think that is quite clear, no?

Try to do what stetim94 says, but I’d add that the problem is that you pass a non-existent field name to addDishToCourse.