freecodecamp - where art thou

where.js

function where(collection, source) {
  var arr = [];
  // What's in a name?
  var key = Object.keys(source);
  
  for( var i = 0; i < collection.length; i++ ){
    
    var counter = 0;
    
    for (var k = 0; k < key.length; k++){
      if(source[key[k]] === collection[i][key[k]]){
        counter++;
      }
    }
    
    if( counter == key.length ){
       arr.push(collection[i]);
    }
  }
  return arr;
}

where([{ "a": 1, "b": 2 }, { "a": 1 }, { "a": 1, "b": 2, "c": 2 }], { "a": 1, "b": 2 });