Formly erroring when used as attribute

[wytrych]

When used in attribute form (like <div formly-form> I get this error: This is not the case when I use it as an element (like <formly-form>). Same behaviour in angular 1.5.8 and 1.4.12.

Minimum form structure to reproduce this:

$scope.fields = [
      {
                fieldGroup: []
      }
];