code: function only( testName, callback ) {
  	var newTest;
  
  	if ( focused )  { return; }
  
  	QUnit.config.queue.length = 0;
  	focused = true;
  
  	newTest = new Test( {
  		testName: testName,
  		callback: callback
  	} );
  
  	newTest.queue();
  }
docs: Will be exposed as QUnit.only