Support foreign thenables in reject()

[jsor]

resolve supports foreign thenables (introduced in #52), so should reject.

[jsor]

Request for review @clue @WyriHaximus @cboden

[WyriHaximus]

LGTM

[clue]

Note sure how useful this actually is, but I don't really mind despite 👍

The instanceof check should be significantly faster and I suppose this may be a function that is called quite often. Does it make sense to OR both conditions and rely on short-circuiting here?

[jsor]

Note sure how useful this actually is, but I don't really mind despite 👍

It is more about being consistent.

The instanceof check should be significantly faster and I suppose this may be a function that is called quite often. Does it make sense to OR both conditions and rely on short-circuiting here?

Usually, you will do reject(new \Exception) or just reject(). So, the method_exists will be called anyway in most cases.

The optimization would be to turn the logic around

function reject($promiseOrValue = null)
{
    if (
        !$promiseOrValue ||
        $promiseOrValue instanceof \Throwable ||
        $promiseOrValue instanceof \Exception ||
        !is_object($promiseOrValue) ||
        !method_exists($promiseOrValue, 'then')
    ) {
        return new RejectedPromise($promiseOrValue);
    }

    return resolve($promiseOrValue)->then(function ($value) {
        return new RejectedPromise($value);
    });
}

[jsor]

Closing as i changed my mind. We probably enforce exceptions as rejection reasons in the future (#46). So, no need to support/encourage usage of thenables as rejection reasons.