How do I unit test a helper that uses a service?

I'm trying to unit test a helper that uses a service.

This is how I inject the service:

export function initialize(container, application) {
  application.inject('view', 'foobarService', 'service:foobar');
}

The helper:

export function someHelper(input) {
  return this.foobarService.doSomeProcessing(input);
}

export default Ember.Handlebars.makeBoundHelper(someHelper);

Everything works until here.

The unit test doesn't know about the service and fails. I tried to:

test('it works', function(assert) {

  var mockView = {
    foobarService: {
      doSomeProcessing: function(data) {
          return "mock result";
      }
    }
  };

  // didn't work
  var result = someHelper.call(mockView, 42);

  assert.ok(result);
});