PocketMine-MP/src/promise/Promise.php
2024-02-06 12:42:24 +00:00

111 lines
3.2 KiB
PHP

<?php
/*
*
* ____ _ _ __ __ _ __ __ ____
* | _ \ ___ ___| | _____| |_| \/ (_)_ __ ___ | \/ | _ \
* | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
* | __/ (_) | (__| < __/ |_| | | | | | | | __/_____| | | | __/
* |_| \___/ \___|_|\_\___|\__|_| |_|_|_| |_|\___| |_| |_|_|
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* @author PocketMine Team
* @link http://www.pocketmine.net/
*
*
*/
declare(strict_types=1);
namespace pocketmine\promise;
use function count;
use function spl_object_id;
/**
* @phpstan-template TValue
*/
final class Promise{
/**
* @internal Do NOT call this directly; create a new Resolver and call Resolver->promise()
* @see PromiseResolver
* @phpstan-param PromiseSharedData<TValue> $shared
*/
public function __construct(private PromiseSharedData $shared){}
/**
* @phpstan-param \Closure(TValue) : void $onSuccess
* @phpstan-param \Closure() : void $onFailure
*/
public function onCompletion(\Closure $onSuccess, \Closure $onFailure) : void{
$state = $this->shared->state;
if($state === true){
$onSuccess($this->shared->result);
}elseif($state === false){
$onFailure();
}else{
$this->shared->onSuccess[spl_object_id($onSuccess)] = $onSuccess;
$this->shared->onFailure[spl_object_id($onFailure)] = $onFailure;
}
}
public function isResolved() : bool{
//TODO: perhaps this should return true when rejected? currently there's no way to tell if a promise was
//rejected or just hasn't been resolved yet
return $this->shared->state === true;
}
/**
* Returns a promise that will resolve only once all the Promises in
* `$promises` have resolved. The resolution value of the returned promise
* will be an array containing the resolution values of each Promises in
* `$promises` indexed by the respective Promises' array keys.
*
* @param Promise[] $promises
*
* @phpstan-template TPromiseValue
* @phpstan-template TKey of array-key
* @phpstan-param non-empty-array<TKey, Promise<TPromiseValue>> $promises
*
* @phpstan-return Promise<array<TKey, TPromiseValue>>
*/
public static function all(array $promises) : Promise{
if(count($promises) === 0){
throw new \InvalidArgumentException("At least one promise must be provided");
}
/** @phpstan-var PromiseResolver<array<TKey, TPromiseValue>> $resolver */
$resolver = new PromiseResolver();
$values = [];
$toResolve = count($promises);
$continue = true;
foreach($promises as $key => $promise){
$promise->onCompletion(
function(mixed $value) use ($resolver, $key, $toResolve, &$values) : void{
$values[$key] = $value;
if(count($values) === $toResolve){
$resolver->resolve($values);
}
},
function() use ($resolver, &$continue) : void{
if($continue){
$continue = false;
$resolver->reject();
}
}
);
if(!$continue){
break;
}
}
return $resolver->getPromise();
}
}