waitForAngular.js

try { return (function (rootSelector, callback) {
  var el = document.querySelector(rootSelector);

  try {
    if (!window.angular) {
      throw new Error('angular could not be found on the window');
    }
    if (angular.getTestability) {
      angular.getTestability(el).whenStable(callback);
    } else {
      if (!angular.element(el).injector()) {
        throw new Error('root element (' + rootSelector + ') has no injector.' +
           ' this may mean it is not inside ng-app.');
      }
      angular.element(el).injector().get('$browser').
          notifyWhenNoOutstandingRequests(callback);
    }
  } catch (err) {
    callback(err.message);
  }
}).apply(this, arguments); }
catch(e) { throw (e instanceof Error) ? e : new Error(e); }