Implement this!

[workmanw]

Originally started: workmanw/ember-diff-attrs#4 .

Rough out of the API provided by @GavinJoyce :

import DidChangeAttrs from 'ember-did-change-attrs';

export default Ember.Component.extend(DidChangeAttrs, {
  didChangeAttrsConfig: {
    attrs: ['email', 'isAdmin']
  },
 
  didChangeAttrs(changes) {
    if(changes.email) {
      let oldEmail = changes.email.previous,
          newEmail = changes.email.current;
      // Do stuff
    }
  }
});

[workmanw]

The biggest concern I had about this API when I looked at it was regarding inheritance. What would happen if someone wanted to extend a component that was using DidChangeAttrs and use it themself? Specifically around the didChangeAttrsConfig.

We could:

1. Say sorry, it's not supported
2. Make it a concatenatedProperties and/or mergedProperties
3. ???

[GavinJoyce]

If it's going to be a hash, mergedProperties seems like a fine solution