Wednesday, October 11, 2017

Extending native objects in create-react-app

Despite being considered a bad practice by some, I like to extend native objects to add some syntatic sugar. However, when working in a React project with create-react-app, I receive the following ESLint error:

Array prototype is read only, properties should not be added  no-extend-native

Fortunately this warning can be disabled by adding a comment in the file where you extend the native object. Putting it all together, this is what I’ve got:

/*eslint no-extend-native: ["error", { "exceptions": ["Array"] }]*/
Object.defineProperty(Array.prototype, 'last', {
  get: function() {
    return this[this.length - 1];
  }
});
Object.defineProperty(Array.prototype, 'empty', {
  get: function() {
    return this.length === 0;
  }
});

Syntatic sugar added, clear console.