Pagination helper - backward count does not work with promises

[akomm]

Q	A
Bug report?	yes
Feature request?	no
BC Break report?	no
RFC?	no
Version/Branch	dev-master

Paginator $count callback does work with promise when using forward, but not backward. In case of backward, you get:

Object of class GraphQL\\Executor\\Promise\\Promise could not be converted to int

Example code:

$paginator = new Paginator(function($offset, $limit) {
    return $this->someLoader->load(new SomeKey($criteria, $offset, $limit))->then(function(array $ids) {
        return $this->someOtherLoader->loadMany($ids);
    });
});
$paginator->auto($args, function() {
    return $this->someLoader->load(new SomeKey($criteria))->then(FnUtils::arrayLikeCount());
});

[mcg-web]

Try this please:

$paginator = new Paginator(function($offset, $limit) {
    return $this->someLoader->load(new SomeKey($criteria, $offset, $limit))->then(function(array $ids) {
        return $this->someOtherLoader->loadMany($ids);
    });
}, Paginator::MODE_PROMISE);

[akomm]

Sorry, I did it already, forgot to add it to the sample code. Otherwise it would not work with forward too.

Also note: the note is raised after the $count callback invokation, not the paginator callback. So the issue is the promise returned from $count:

$paginator->auto($args, function() {
    return $this->someLoader->load(new SomeKey($criteria))->then(FnUtils::arrayLikeCount());
});

arrayLikeCount is a x => count(x); with some checks.

[akomm]

I think the reason, why the notice does not trigger in case of forward is because it is not accessed there, while the backward does access the Connection::$totalCount and therefore triggers the error. So probably the issue is in general, that the $count callback in Paginator is not supporting promise itself?