Record collection: canonical answer does not work.

Record Collection

https://www.freecodecamp.com/challenges/record-collection#

Issue Description

The solution as posted on the FCC wiki does not work. After trying a number of solutions, I looked at the wiki for help on a particular aspect of the answer which ended up being the same as my own answer. So, I copied both my code and another non-functional answer, reset the code to the problem, pasted and commented out the failed attempts, copied the solution from the wiki, and pasted in the solution on the wiki. None of the aspects of the challenge are credited

Browser Information

• Safari, Version 9:
• Operating System: OS X 10.11
• Mobile, Desktop, or Tablet: Laptop

Your Code (my answer first, then another FCC member)

 if (value !=="")  {
      if ([id][prop] !=="tracks") {
       collection[id][prop] = value;          // this part works
      } else {
       collection[id][prop].push(value);     // no love for this part    
      }
   }
  else {
      delete collection[id][prop];             // this part works
  }

Another answer that didn’t work:

  function updateRecords(id, prop, value) {
  if (prop === "tracks" && value !== "") {
    collection[id][prop].push(value);
  } else if (value !== ""){
    collection[id][prop] = value;
  } else {
    delete collection[id][prop];
  }

Screenshot (taken straight from the wiki, pasted and ran – with results)

[Niklus]

Found a little bug: The code below is wrong but is accepted as a right answer.

function updateRecords(id, prop, value) { if(value === “”){ delete collection[id][prop]; }else if(prop === “tracks”){ collection[id][prop] = []; collection[id][prop].push(value); }else { collection[id][prop] = value;} return collection;}

The correct answer should be the following - which works too. It checks first if the property “tracks” exists (if collection[id][prop] is true) before pushing. If it doesnt exist it creates a new array.

function updateRecords(id, prop, value) { if(value === “”){ delete collection[id][prop]; } else if (prop === “tracks” && collection[id][prop]){ // check if property exists collection[id][prop].push(value); }else if(prop === “tracks”){ collection[id][prop] = []; // initialize a new array before pushing collection[id][prop].push(value); } else { collection[id][prop] = value; } return collection;}

[ghost]

@hrokr The real issue is your code, it’s trying to push onto a non existent array at a non existent key. If you really want to keep your code like this, you would need something like this:

function updateRecords(id, prop, value) {
  if (value !== ""){
    if(prop !== "tracks"){
      collection[id][prop] = value;
    }else{
      if(!collection[id][prop]){
        collection[id][prop] = [];
      }
      collection[id][prop].push(value);
    }
  }else{
    delete collection[id][prop];
  }

  return collection;
}

Perhaps there is something wrong with the ‘output’ window. The code I have provided passes but the ‘results’ are the same as your screenshot. But verified locally the code returns the expected result.