Question

Why does the “fullName” function in this code execute twice?

Person = Ember.Object.extend({
  // these will be supplied by `create`
  firstName: null,
  lastName: null,
  fullName: function() {
    console.log('Full name function...');
    var firstName = this.get('firstName');
    var lastName = this.get('lastName');
    return firstName + ' ' + lastName;
  }.property('firstName', 'lastName')
});

App.tom = Person.create({
  firstName: "Tom",
  lastName: "Dale"
});

App.UsersView = Ember.View.create({
    templateName: 'users',
    users: [App.tom]
});

Later in google-chrome console:

App.tom.set('firstName', 'John')

This outputs to log twice.

Answer 1

Seems like a bug, indeed (added a JSFiddle to illustrate: http://jsfiddle.net/MikeAski/GRvgt/)…

The view is rerendered, and the computed property not cached yet. 🙁