fails on overriden prototype functions

[slavah]

Hey Nate - amazing lib, was looking for something like this for long time. While playing with it found some issues. Cant really call it a bug, i understand its more of a PEG issue. What do you think?

Test Code:

 var matcher = matches.pattern({
                '{record, ...}': function (val) {     //first line always would match
                    return record = 'first';
                },
                "record@{className:'testClass', ...}": function (val, obj) {
                    return record = 'second';
                },
  });
  var testObj = function() {
                this.a = 5;
                this.toString = function() { return 'This would cause issues';  };
            };
   testObj.prototype.className = 'testClass';
   var f = new testObj();

   matcher (f);
   expect(record == 'second').toBeTruthy();    //fails

The issue is in this function in PatternFn:

function(args,runt) { //.... for (var arg_0_i in arg_0) { if (arg_0_i in arg_0_keys) arg_0_count += 1; //its going to match on every toString in prototype chain. } if (arg_0_count !== 1) return false; //..... };

Thanks.

[natefaubion]

Not a PEG issue. I had a naive lookup in the compiled function. It creates a lookup object for keys to watch out for when iterating over the object. I was just using in to check for a key's presence in the lookup object. That was causing your explicit toString to match the prototype toString of the lookup object. Fixed by using hasOwnProperty instead.

[slavah]

Oh i see, i was under impression that peg was generating those functions. Yes, now i see that you are defining pattern in matches and compiling in compiler.js.

Thanks a lot for quickly fixing it.