Reusing the main components of https://github.com/wrozka/capybara-angular, but made to be a "drop-in" module. Just use `wait_until_ready` whenever you want Capybara to catch-up to any Angular requests.

AngularWaiter

module AngularWaiter
  def setup_ready
    page.execute_script <<-JS
      window.angularReady = false;
      var app = $('*[ng-app]');
      var injector = app.injector();

      injector.invoke(function($browser) {
        $browser.notifyWhenNoOutstandingRequests(function() {
          window.angularReady = true;
        });
      });
    JS
  end

  def ready?
    page.evaluate_script("window.angularReady")
  end

  def wait_until_ready
    setup_ready
    until ready?
      sleep(0.01)
    end
  end
end