How to determine when the recursion ends?

Question

JavaScript

How to determine the end of execution of such a recursive function:

function rec(text) {
    asynFunc(text).then(data => {
        if (data.length > 10) {
            rec(data);
        }
    })
}

Answer 1

function rec(text) {
    return asynFunc(text).then(data => {
        if (data.length > 10) {
            return rec(data);
        }
    })
}

rec(text).then(() => console.log("Закончилось"));

Answer 2

It depends on asynFunc()
As soon as the promise in it is fulfilled with a result that does not satisfy the condition, it will end.
If asynFunc always returns the same value with the same argument, it will never end.