Stack-safety for free?

stack_safe.js

// This gist contains the JavaScript version of the code from the blog post
// https://hurryabit.github.io/blog/stack-safety-for-free/
function triangular(n) {
    if (n == 0) {
        return 0;
    } else {
        return n + triangular(n - 1);
    }
}

function trampoline(f) {
    function mu_f(arg) {
        const stack = [];
        let current = f(arg);
        let res = undefined;

        while (true) {
            const { done, value } = current.next(res);
            if (!done) {
                stack.push(current);
                current = f(value);
                res = undefined;
            } else {
                if (stack.length > 0) {
                    current = stack.pop();
                    res = value;
                } else {
                    return value;
                }
            }
        }
    }

    return mu_f;
}

const triangular_safe = trampoline(function* (n) {
    if (n == 0) {
        return 0;
    } else {
        return n + (yield (n - 1));
    }
});

const LARGE = 100_000;
console.clear();

if (triangular_safe(LARGE) != LARGE * (LARGE + 1) / 2) {
    throw Error("`triangular_safe` computed wrong value.");
}
console.log("`triangular_safe` has not overflowed its stack.");

console.log("`triangular` will overflow its stack soon...");
try {
    triangular(LARGE);
    throw Error("`triangular` has not overflowed its stack.");
} catch (exc) {
    if (exc.message.includes("call stack")) {
        console.log("`triangular` has overflowed its stack.")
    } else {
        throw exc;
    }
}