didInitAttrs cannot see bound values unless they are explicitly defined on the component class.

[jakesjews]

I just noticed this in 1.13.7. If a property isn't explicitly defined on a component's class then its value is never seen in the didInitAttrs method even though it is bound in the template. Defining the property with a value of null does work but this wasn't required in 1.13.6. I'm not 100% sure if this is a bug or if the previous behavior was incorrect and it's been fixed now.

Ember-twiddle at http://ember-twiddle.com/62d39c8e4f57e0eb1fbb

[aortbals]

I can confirm this bug. Immediately after upgrading, I am seeing undefined for an attribute passed to a component in init of the component:

{{foo-component bar='something'}}

init() {
  Ember.assert("The {{foo-component}} attribute 'bar' was not configured", this.get('bar'));
},

The following assert throws in 1.13.7 where it would be correctly bound to 'something' in 1.13.6. I can also confirm that defining the attribute on the component as null fixes the issue. In my experience, it is pretty common to see attributes passed to the component that aren't explicitly defined (regardless of what people feel about the practice of non-explicit attributes).

[ghost]

I bumped into this too. This was during didReceiveAttrs.
If you declare foo: null on the object things work again.

Here is a jsbin: http://emberjs.jsbin.com/femezafave/1/edit?html,js,console,output

Edit: getAttr does work.

[EricSchank]

I think I have a fix for this, but I'm writing a test to verify -- unless one of you has a breaking test already?

[aortbals]

I do not. That's great to hear though!

[noslouch]

don't have a breaking test, just a breaking app :-/

[gerry3]

+1

[rwjblue]

Fixed by #12071.

[rwjblue]

Will be in a 1.13.8 soonish.