How do I trigger a keyup/keydown event in an angularjs unit test?

Question

I want to unit test a directive that emulates a placeholder, where the input value is cleared only on keyup/down events.

Answer 1

You need to create an event programatically and trigger it. To do so including jQuery for unit tests is quite useful. For example, you could write a simple utility like this:

  var triggerKeyDown = function (element, keyCode) {
    var e = $.Event("keydown");
    e.which = keyCode;
    element.trigger(e);
  };

and then use it in your unit test like so:

triggerKeyDown(element, 13);

You can see this technique in action in the http://angular-ui.github.io/bootstrap/ project here: https://github.com/angular-ui/bootstrap/blob/master/src/typeahead/test/typeahead.spec.js

Disclaimer: let's be precise here: I'm not advocating using jQuery with AngularJS! I'm just saying that it is a useful DOM manipulation utility for writing tests interacting with the DOM.

To make the above code work without jQuery, change:

$.Event('keydown')

to:

angular.element.Event('keydown')