ngMessages blows up when there are duplicate child ngMessage keys

[niallsmart]

The ngMessages directive gets into an invalid state and throws an exception when there are duplicate ngMessage child keys specified. For example:

<div ng-messages="form.id.$error">
  <div ng-message="required">
    User ID is required.
  </div>
  <div ng-message="required">
    User ID is required.
  </div>
</div>

The issue seems to be a bug in the re-ordering logic in registerMessage which is attempting to preserve the ordering from an included template, but in this scenario inserts null into messages.

Test case here: http://plnkr.co/edit/7u4oFTGbeLqa1tmfMNlJ (look at the console log).

[btford]

I don't think we want to support this behavior. What's your use-case?

[niallsmart]

@btford it was actually a typo, but I expected to see it handled more gracefully :)

[btford]

@IgorMinar do you think it makes sense to improve the error message in this case?

[matsko]

It should just silently ignore the 2nd occurrence.

[matsko]

#10676 will fix this for 1.3 and 1.4