You don't need parentheses for a single argument

I'm surprised this works, I had to return a function because Angular complained about an infinite look. Needs further testing.

Something bothers me: users can't opt out for ajax autocompletion. That means that if their API doesn't implement the search query param, reference fields cease to work. This is a serious BC break.

Autocomplete should be opt-in ; the default behavior should still be to fetch all possible values, and only autocomplete locally.

Actually, this is already dealt through the field.refreshDelay parameter. If it's null, then all choices would be retrieved, the same as before my changes.

I put the API request behavior by default, as it sounds more logical to me for references. Indeed, user doesn't know how many records there is remotely. And it is more probable that there is a lot. It would then be limited by the perPage parameter.

This is indeed a BC break, but it improves the component behavior IMO.

As seen with @fzaninotto, we'll set refreshDelay to null by default.

Moreover, you must make it more explicit that in the doc that a Reference is populated by the entire list of references, and that if the developer wants to use autocomplete, they should set the refreshdelay to something more than null.