What am i missing guys on Where art Thou challenge?

JavaScript
1

I am sensing I am missing smth very obvious so please hint at the mistake as to why I am not getting any output from d, but an empty array?

Any help is appreciated

  // Only change code below this line
  var o = Object.entries(source);
  // Only change code above this line
  var a = Object.entries(collection);
  
 
  for(i = 0; i < Object.keys(collection).length; i++){
    arr.push(collection[i]);
  }
  
 
  var keySource =  Object.keys(source);
  var d = 0;
 
  
  for(var z = 0; z < arr.length; z++){
     for(var j = 0; j < keySource.length; j++){
    if(arr[z][keySource[j]] == source[keySource[j]]){
    d.push(arr[z]);
}

      }  
    return d;

  }

}

whatIsInAName([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" });
3

Thanks, sorry must have posted the incorrect version of the code I had initially, apologies.
That is the one I meant to post. The only thing I actually missed out on here is the return statement that came too early originally.

I can pass the first two checks, but not the last two. I can see with the output checks that my conditions are way too sloppy as any match is enough to put the element in the final d array. I guess I more or less understand what I need to change now.

Thanks for the help again! A good constructive answer. Apologies for posting the stuff that was not what I intended to post which caused a couple of extra issues you picked up on that were not meant to be there.

Cheers

function whatIsInAName(collection, source) {
  // What's in a name?
  var arr = [];
  // Only change code below this line
  var o = Object.entries(source);
  // Only change code above this line
  var a = Object.entries(collection);
  
 
  for(i = 0; i < Object.keys(collection).length; i++){
    arr.push(collection[i]);
  }
  
 
  var keySource =  Object.keys(source);
  var d = [];
 
  
  for(var z = 0; z < arr.length; z++){
     for(var j = 0; j < keySource.length; j++){
    if(arr[z][keySource[j]] == source[keySource[j]]){
    d.push(arr[z]);
}

      }  

  }

      return d;
5

Thank you, of course you are right, this is the one thing every programmer should bear in mind.

Cheers