add timeoutWithDefault function

[prolic]

see #244

[kelunik]

An exception should probably be thrown here instead of resulting in the default value.

[prolic]

You're right, give me a minute.

[kelunik]

I wouldn't make use of the timeout function, but rather adapt the code of it to suit this function.

[prolic]

No wait, that's the whole purpose of the default value. You timeout with a default and when you'll receive a timeout exception, you'll get the default value.

[kelunik]

You'll get the default on a timeout, but not if the promise fails?

[prolic]

@kelunik updated

[trowski]

This is way less code:

function timeoutWithDefault($promise, int $timeout, $default = null): Promise
{
    return call(function () use ($promise, $timeout, $default) {
        try {
            return yield timeout($promise, $timeout);
       } catch (TimeoutException $excetpion) {
            return $default;
       }
    });
}

This is so little code that I question the need for this, but also so little that I don't really care maintance-wise either.

[prolic]

@trowski: @kelunik asked me not to reuse the timeout function. I know it's not much code, but having those 7 lines of code 50 times in your code base really sucks :)

[trowski]

I think mostly because you originally didn't use timeout() within a coroutine, which then makes it nearly as complicated. Otherwise I see no reason to not reuse the function.

You can define functions in your code base you know. 😉 But yes, I can see where this can be useful for many people, so let's add it.

[prolic]

@trowski I tested your suggested implementation and then this test fails, because the TypeError is not thrown.

[trowski]

It should be…

[trowski]

Oh, right, because it's not resolving the promise with the TypeError. Fine, then it needs to be this way:

function timeoutWithDefault($promise, int $timeout, $default = null): Promise
{
    $promise = timeout($promise, $timeout);

    return call(function () use ($promise, $default) {
        try {
            return yield $promise;
        } catch (TimeoutException $exception) {
            return $default;
        }
    });
}

[trowski]

Totally my fault, but typo: $excetpion 😄

[trowski]

The style fixer is going to yell at you. 🙄
Otherwise looks good.

[prolic]

done