Code working but failing test

Tell us what’s happening:

Hey guys, I’ve tested my code doing set1.union(set2), with set1.values() = [“a”, “b”, “c”] and set2.values() = [“c”, “d”]. Is correctly returning [“a”, “b”, “c”, “d”]

Your code so far

class Set {
constructor() {
// This will hold the set
this.dictionary = {};
this.length = 0;
}
// This method will check for the presence of an element and return true or false
has(element) {
return this.dictionary[element] !== undefined;
}
// This method will return all the values in the set
values() {
return Object.keys(this.dictionary);
}
// This method will add an element to the set
add(element) {
if (!this.has(element)) {
this.dictionary[element] = true;
this.length++;
return true;
}

return false;

}
// This method will remove an element from a set
remove(element) {
if (this.has(element)) {
delete this.dictionary[element];
this.length–;
return true;
}

return false;

}
// This method will return the size of the set
size() {
return this.length;
}
// Only change code below this line
union(otherSet) {
var result = this.values()
otherSet.values().forEach(value => {
if (!this.has(value)) {
result.push(value)
}
})
return result
}
// Only change code above this line
}


class Set {
constructor() {
  // This will hold the set
  this.dictionary = {};
  this.length = 0;
}
// This method will check for the presence of an element and return true or false
has(element) {
  return this.dictionary[element] !== undefined;
}
// This method will return all the values in the set
values() {
  return Object.keys(this.dictionary);
}
// This method will add an element to the set
add(element) {
  if (!this.has(element)) {
    this.dictionary[element] = true;
    this.length++;
    return true;
  }

  return false;
}
// This method will remove an element from a set
remove(element) {
  if (this.has(element)) {
    delete this.dictionary[element];
    this.length--;
    return true;
  }

  return false;
}
// This method will return the size of the set
size() {
  return this.length;
}
// Only change code below this line
union(otherSet) {
  var result = this.values()
  otherSet.values().forEach(value => {
    if (!this.has(value)) {
      result.push(value)
    }
  })
  return result
}
// Only change code above this line
}

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Challenge: Perform a Union on Two Sets

Link to the challenge:

could you please format this post…
Surround your code with triple backticks(```)