Record Collection Cannot read property 'push' of defined

JavaScript
1

What`s wrong with this?

error message: Cannot read property ‘push’ of undefined


// Setup
var collection = {
    "2548": {
      "album": "Slippery When Wet",
      "artist": "Bon Jovi",
      "tracks": [ 
        "Let It Rock", 
        "You Give Love a Bad Name" 
      ]
    },
    "2468": {
      "album": "1999",
      "artist": "Prince",
      "tracks": [ 
        "1999", 
        "Little Red Corvette" 
      ]
    },
    "1245": {
      "artist": "Robert Palmer",
      "tracks": [ ]
    },
    "5439": {
      "album": "ABBA Gold"
    }
};
// Keep a copy of the collection for tests
var collectionCopy = JSON.parse(JSON.stringify(collection));

// Only change code below this line
function updateRecords(id, prop, value) {
if(collection.hasOwnProperty(id)){
  if(prop !== "tracks" && value !==""){
    collection[id][prop] = value;
  }
  if(prop == "tracks" && value !==""){
    collection[id][prop].push(value);
  }
  else if(prop == "tracks" && !collection.hasOwnProperty(prop)){

  collection[id][prop] =[value];
  }
   if(value == ""){
    delete collection[id][prop];
  }
}


  return collection;
}

// Alter values below to test your code
updateRecords(5439, "artist", "ABBA");

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/record-collection/

2 
 if(prop == "tracks" && value !==""){
    collection[id][prop].push(value);
  }
  else if(prop == "tracks" && !collection.hasOwnProperty(prop)){

  collection[id][prop] =[value];
  }

That if does not check whether the record has a “tracks” property, so it tries to push to undefined. Your else if only runs if prop == "tracks" && value !=="" is false. It only runs if prop is “tracks”, value is “”, and collection does not have a property “tracks”. (Note: you are checking whether collection has the property, not whether the record does.)

1 Like
3

Thanks! I was getting burned out and overlooked that like 50 times haha.