TypeError for Ember.computed.sort in DependentArraysObserver.prototype.dependentArrayWillChange

[rhyek]

I'm using Ember 1.7 and having an issue with DependentArraysObserver.prototype.dependentArrayWillChange at line 25860 (http://builds.emberjs.com/tags/v1.7.0/ember.js) where a TypeError is raised because observerContexts[sliceIndex] is undefined:

observerContexts[sliceIndex].destroyed = true;

I have a jsbin here. (click on 'clear'). The problem only seems to occur in the specific case where i have both sortableTable views up (even though they're independent of each other) and at least the second has it's Ember.computed.sort computed property's sortProperties set to a non-empty array.

I've noticed that just before the exception is raised, at line 25815 when this line is called inside trackRemove:

var trackedArray = this.trackedArraysByGuid[dependentKey];

trackedArray is undefined while dependentArray still points to my underlying data.

In any case, changing this:

function removeObservers(propertyKey) {
    observerContexts[sliceIndex].destroyed = true;
    removeBeforeObserver(item, propertyKey, this, observerContexts[sliceIndex].beforeObserver);
    removeObserver(item, propertyKey, this, observerContexts[sliceIndex].observer);
}

to this:

function removeObservers(propertyKey) {
    if (typeof observerContexts[sliceIndex] !== 'undefined') {
        observerContexts[sliceIndex].destroyed = true;
        removeBeforeObserver(item, propertyKey, this, observerContexts[sliceIndex].beforeObserver);
        removeObserver(item, propertyKey, this, observerContexts[sliceIndex].observer);
    }
}

solves my problem.

[wagenet]

@rhyek can you check this in 1.8?

[rhyek]

Just updated that jsbin to ember 1.8.0 and ember-data 1 beta 11. Still has the same issue.

http://emberjs.jsbin.com/kiqipiguqi/1/edit

[wagenet]

Merging into #9462