Even Fibonacci numbers

Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.

Comment used to generate the code:

function that returns the sum of all even fibonacci numbers below a given number

function sumEvenFibonacci(num: number): number {

      let sum: number = 0;

      let fibonacci: number[] = [1, 2];

      while (fibonacci[fibonacci.length - 1] < num) {

          fibonacci.push(fibonacci[fibonacci.length - 1] + fibonacci[fibonacci.length - 2]);

      }

      for (let i: number = 0; i < fibonacci.length; i++) {

          if (fibonacci[i] % 2 === 0) {

              sum += fibonacci[i];

          }

      }

      return sum;

    }

Thoughts:

I had previously solved this one myself and its interesting to see how copilot's solution differs, using a while loop to get the numbers and then using a for loop to get the even numbers.