anchor.diff:  [role="executable"]
   [source,javascript]
   ----
  -var promise = new Promise(function(resolve ,reject){
  +var promise = new Promise(function(resolve, reject){
       reject(new Error("message"));
   });
   promise.catch(function(error){
  
positive.code: 
  [source,javascript]
  ----
  var promise = new Promise(function(resolve ,reject){
      throw new Error("message");
  });
  ----
  
negative.code: [role="executable"]
  [source,javascript]
  ----
  var promise = new Promise(function(resolve, reject){
      throw new Error("message");
  });
  promise.catch(function(error){
  