mono/packages/kbot/tests/test-data/code/fibonacci.js

function fibonacci(n) {
    if (n <= 0) return 0;
    if (n === 1) return 1;
    let a = 0, b = 1;
    for (let i = 2; i <= n; i++) {
        let temp = a + b;
        a = b;
        b = temp;
    }
    return b;
}