Confusing error message when the default body attribute not provided

[PK1A]

Consider this component definition:

var CollapseCpt = function () {
    this.show = true;
    this.toggleShow = function () {
        this.show = !this.show;
    };
};

CollapseCpt.prototype.attributes = {
    title: {type: "string", binding: "1-way"},
    type: {type: "string", binding: "1-way"},
    "body":{type:"template",defaultContent:true}
};

and the example usage (notice empty body):

<#collapse title="Evolution of Online and Offline Bookings" type="Chart">
</#collapse>

As of today this results in the following error message:

[error] [Component: #ctrl.body] Invalid component reference

The error is confusing as it doesn't provide any clue on what is actually wrong. But more importantly this scenario shouldn't fail, IMO.