Code QuizAdvanced

Inheritance and the super() Call

Spot the classic subclass constructor bug that breaks JavaScript inheritance.

Codejavascript

class Animal {
  constructor(name) {
    this.name = name;
  }
  speak() {
    return `${this.name} makes a sound`;
  }
}

class Dog extends Animal {
  constructor(name, breed) {
    this.breed = breed;
    super(name);
  }
  speak() {
    return `${this.name} barks`;
  }
}

const d = new Dog('Rex', 'Labrador');
console.log(d.speak());

What is the bug in the Dog class, and how do you fix it?

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