code: function(assert, mActual, mExpected, sMessage) {
  		var aUnexpectedElements = [];
  
  		for (var sId in mActual) {
  			if (!mExpected[sId]) {
  				aUnexpectedElements.push(mActual[sId]);
  			}
  		}
  
  		// enrich with helpful info to more easily identify the leaked control
  		for (var i = 0; i < aUnexpectedElements.length; i++) {
  			if (typeof aUnexpectedElements[i].getText === "function") {
  				aUnexpectedElements[i] += " (text: '" + aUnexpectedElements[i].getText() + "')";
  			}
  		}
  
  		sMessage = sMessage + (aUnexpectedElements.length > 0 ? ". LEFTOVERS: " + aUnexpectedElements.join(", ") : "");
  		assert.equal(aUnexpectedElements.length, 0, sMessage);
  	}
docs: asserts that both given maps have the same entries