[Php-blog-plugin-cvs] additional_plugins/serendipity_event_browserid/vendor/guzzlehttp/promises/src AggregateException.php, NONE, 1.1 CancellationException.php, NONE, 1.1 Coroutine.php, NONE, 1.1 EachPromise.php, NONE, 1.1 FulfilledPromise.php, NONE, 1.1 Promise.php, NONE, 1.1 PromiseInterface.php, NONE, 1.1 PromisorInterface.php, NONE, 1.1 RejectedPromise.php, NONE, 1.1 RejectionException.php, NONE, 1.1 TaskQueue.php, NONE, 1.1 TaskQueueInterface.php, NONE, 1.1 functions.php, NONE, 1.1 functions_include.php, NONE, 1.1

[Serendipity C. <s9...@us...>]

Update of /cvsroot/php-blog/additional_plugins/serendipity_event_browserid/vendor/guzzlehttp/promises/src
In directory sfp-cvs-1.v30.ch3.sourceforge.com:/tmp/cvs-serv18870/serendipity_event_browserid/vendor/guzzlehttp/promises/src

Added Files:
	AggregateException.php CancellationException.php Coroutine.php 
	EachPromise.php FulfilledPromise.php Promise.php 
	PromiseInterface.php PromisorInterface.php RejectedPromise.php 
	RejectionException.php TaskQueue.php TaskQueueInterface.php 
	functions.php functions_include.php 
Log Message:
gitclone.sh autocommit

--- NEW FILE: functions.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * Get the global task queue used for promise resolution.
 *
 * This task queue MUST be run in an event loop in order for promises to be
 * settled asynchronously. It will be automatically run when synchronously
 * waiting on a promise.
 *
 * <code>
 * while ($eventLoop->isRunning()) {
 *     GuzzleHttp\Promise\queue()->run();
 * }
 * </code>
 *
 * @param TaskQueueInterface $assign Optionally specify a new queue instance.
 *
 * @return TaskQueueInterface
 */
function queue(TaskQueueInterface $assign = null)
{
    static $queue;

    if ($assign) {
        $queue = $assign;
    } elseif (!$queue) {
        $queue = new TaskQueue();
    }

    return $queue;
}

/**
 * Adds a function to run in the task queue when it is next `run()` and returns
 * a promise that is fulfilled or rejected with the result.
 *
 * @param callable $task Task function to run.
 *
 * @return PromiseInterface
 */
function task(callable $task)
{
    $queue = queue();
    $promise = new Promise([$queue, 'run']);
    $queue->add(function () use ($task, $promise) {
        try {
            $promise->resolve($task());
        } catch (\Throwable $e) {
            $promise->reject($e);
        } catch (\Exception $e) {
            $promise->reject($e);
        }
    });

    return $promise;
}

/**
 * Creates a promise for a value if the value is not a promise.
 *
 * @param mixed $value Promise or value.
 *
 * @return PromiseInterface
 */
function promise_for($value)
{
    if ($value instanceof PromiseInterface) {
        return $value;
    }

    // Return a Guzzle promise that shadows the given promise.
    if (method_exists($value, 'then')) {
        $wfn = method_exists($value, 'wait') ? [$value, 'wait'] : null;
        $cfn = method_exists($value, 'cancel') ? [$value, 'cancel'] : null;
        $promise = new Promise($wfn, $cfn);
        $value->then([$promise, 'resolve'], [$promise, 'reject']);
        return $promise;
    }

    return new FulfilledPromise($value);
}

/**
 * Creates a rejected promise for a reason if the reason is not a promise. If
 * the provided reason is a promise, then it is returned as-is.
 *
 * @param mixed $reason Promise or reason.
 *
 * @return PromiseInterface
 */
function rejection_for($reason)
{
    if ($reason instanceof PromiseInterface) {
        return $reason;
    }

    return new RejectedPromise($reason);
}

/**
 * Create an exception for a rejected promise value.
 *
 * @param mixed $reason
 *
 * @return \Exception|\Throwable
 */
function exception_for($reason)
{
    return $reason instanceof \Exception || $reason instanceof \Throwable
        ? $reason
        : new RejectionException($reason);
}

/**
 * Returns an iterator for the given value.
 *
 * @param mixed $value
 *
 * @return \Iterator
 */
function iter_for($value)
{
    if ($value instanceof \Iterator) {
        return $value;
    } elseif (is_array($value)) {
        return new \ArrayIterator($value);
    } else {
        return new \ArrayIterator([$value]);
    }
}

/**
 * Synchronously waits on a promise to resolve and returns an inspection state
 * array.
 *
 * Returns a state associative array containing a "state" key mapping to a
 * valid promise state. If the state of the promise is "fulfilled", the array
 * will contain a "value" key mapping to the fulfilled value of the promise. If
 * the promise is rejected, the array will contain a "reason" key mapping to
 * the rejection reason of the promise.
 *
 * @param PromiseInterface $promise Promise or value.
 *
 * @return array
 */
function inspect(PromiseInterface $promise)
{
    try {
        return [
            'state' => PromiseInterface::FULFILLED,
            'value' => $promise->wait()
        ];
    } catch (RejectionException $e) {
        return ['state' => PromiseInterface::REJECTED, 'reason' => $e->getReason()];
    } catch (\Throwable $e) {
        return ['state' => PromiseInterface::REJECTED, 'reason' => $e];
    } catch (\Exception $e) {
        return ['state' => PromiseInterface::REJECTED, 'reason' => $e];
    }
}

/**
 * Waits on all of the provided promises, but does not unwrap rejected promises
 * as thrown exception.
 *
 * Returns an array of inspection state arrays.
 *
 * @param PromiseInterface[] $promises Traversable of promises to wait upon.
 *
 * @return array
 * @see GuzzleHttp\Promise\inspect for the inspection state array format.
 */
function inspect_all($promises)
{
    $results = [];
    foreach ($promises as $key => $promise) {
        $results[$key] = inspect($promise);
    }

    return $results;
}

/**
 * Waits on all of the provided promises and returns the fulfilled values.
 *
 * Returns an array that contains the value of each promise (in the same order
 * the promises were provided). An exception is thrown if any of the promises
 * are rejected.
 *
 * @param mixed $promises Iterable of PromiseInterface objects to wait on.
 *
 * @return array
 * @throws \Exception on error
 * @throws \Throwable on error in PHP >=7
 */
function unwrap($promises)
{
    $results = [];
    foreach ($promises as $key => $promise) {
        $results[$key] = $promise->wait();
    }

    return $results;
}

/**
 * Given an array of promises, return a promise that is fulfilled when all the
 * items in the array are fulfilled.
 *
 * The promise's fulfillment value is an array with fulfillment values at
 * respective positions to the original array. If any promise in the array
 * rejects, the returned promise is rejected with the rejection reason.
 *
 * @param mixed $promises Promises or values.
 *
 * @return PromiseInterface
 */
function all($promises)
{
    $results = [];
    return each(
        $promises,
        function ($value, $idx) use (&$results) {
            $results[$idx] = $value;
        },
        function ($reason, $idx, Promise $aggregate) {
            $aggregate->reject($reason);
        }
    )->then(function () use (&$results) {
        ksort($results);
        return $results;
    });
}

/**
 * Initiate a competitive race between multiple promises or values (values will
 * become immediately fulfilled promises).
 *
 * When count amount of promises have been fulfilled, the returned promise is
 * fulfilled with an array that contains the fulfillment values of the winners
 * in order of resolution.
 *
 * This prommise is rejected with a {@see GuzzleHttp\Promise\AggregateException}
 * if the number of fulfilled promises is less than the desired $count.
 *
 * @param int   $count    Total number of promises.
 * @param mixed $promises Promises or values.
 *
 * @return PromiseInterface
 */
function some($count, $promises)
{
    $results = [];
    $rejections = [];

    return each(
        $promises,
        function ($value, $idx, PromiseInterface $p) use (&$results, $count) {
            if ($p->getState() !== PromiseInterface::PENDING) {
                return;
            }
            $results[$idx] = $value;
            if (count($results) >= $count) {
                $p->resolve(null);
            }
        },
        function ($reason) use (&$rejections) {
            $rejections[] = $reason;
        }
    )->then(
        function () use (&$results, &$rejections, $count) {
            if (count($results) !== $count) {
                throw new AggregateException(
                    'Not enough promises to fulfill count',
                    $rejections
                );
            }
            ksort($results);
            return array_values($results);
        }
    );
}

/**
 * Like some(), with 1 as count. However, if the promise fulfills, the
 * fulfillment value is not an array of 1 but the value directly.
 *
 * @param mixed $promises Promises or values.
 *
 * @return PromiseInterface
 */
function any($promises)
{
    return some(1, $promises)->then(function ($values) { return $values[0]; });
}

/**
 * Returns a promise that is fulfilled when all of the provided promises have
 * been fulfilled or rejected.
 *
 * The returned promise is fulfilled with an array of inspection state arrays.
 *
 * @param mixed $promises Promises or values.
 *
 * @return PromiseInterface
 * @see GuzzleHttp\Promise\inspect for the inspection state array format.
 */
function settle($promises)
{
    $results = [];

    return each(
        $promises,
        function ($value, $idx) use (&$results) {
            $results[$idx] = ['state' => PromiseInterface::FULFILLED, 'value' => $value];
        },
        function ($reason, $idx) use (&$results) {
            $results[$idx] = ['state' => PromiseInterface::REJECTED, 'reason' => $reason];
        }
    )->then(function () use (&$results) {
        ksort($results);
        return $results;
    });
}

/**
 * Given an iterator that yields promises or values, returns a promise that is
 * fulfilled with a null value when the iterator has been consumed or the
 * aggregate promise has been fulfilled or rejected.
 *
 * $onFulfilled is a function that accepts the fulfilled value, iterator
 * index, and the aggregate promise. The callback can invoke any necessary side
 * effects and choose to resolve or reject the aggregate promise if needed.
 *
 * $onRejected is a function that accepts the rejection reason, iterator
 * index, and the aggregate promise. The callback can invoke any necessary side
 * effects and choose to resolve or reject the aggregate promise if needed.
 *
 * @param mixed    $iterable    Iterator or array to iterate over.
 * @param callable $onFulfilled
 * @param callable $onRejected
 *
 * @return PromiseInterface
 */
function each(
    $iterable,
    callable $onFulfilled = null,
    callable $onRejected = null
) {
    return (new EachPromise($iterable, [
        'fulfilled' => $onFulfilled,
        'rejected'  => $onRejected
    ]))->promise();
}

/**
 * Like each, but only allows a certain number of outstanding promises at any
 * given time.
 *
 * $concurrency may be an integer or a function that accepts the number of
 * pending promises and returns a numeric concurrency limit value to allow for
 * dynamic a concurrency size.
 *
 * @param mixed        $iterable
 * @param int|callable $concurrency
 * @param callable     $onFulfilled
 * @param callable     $onRejected
 *
 * @return PromiseInterface
 */
function each_limit(
    $iterable,
    $concurrency,
    callable $onFulfilled = null,
    callable $onRejected = null
) {
    return (new EachPromise($iterable, [
        'fulfilled'   => $onFulfilled,
        'rejected'    => $onRejected,
        'concurrency' => $concurrency
    ]))->promise();
}

/**
 * Like each_limit, but ensures that no promise in the given $iterable argument
 * is rejected. If any promise is rejected, then the aggregate promise is
 * rejected with the encountered rejection.
 *
 * @param mixed        $iterable
 * @param int|callable $concurrency
 * @param callable     $onFulfilled
 *
 * @return PromiseInterface
 */
function each_limit_all(
    $iterable,
    $concurrency,
    callable $onFulfilled = null
) {
    return each_limit(
        $iterable,
        $concurrency,
        $onFulfilled,
        function ($reason, $idx, PromiseInterface $aggregate) {
            $aggregate->reject($reason);
        }
    );
}

/**
 * Returns true if a promise is fulfilled.
 *
 * @param PromiseInterface $promise
 *
 * @return bool
 */
function is_fulfilled(PromiseInterface $promise)
{
    return $promise->getState() === PromiseInterface::FULFILLED;
}

/**
 * Returns true if a promise is rejected.
 *
 * @param PromiseInterface $promise
 *
 * @return bool
 */
function is_rejected(PromiseInterface $promise)
{
    return $promise->getState() === PromiseInterface::REJECTED;
}

/**
 * Returns true if a promise is fulfilled or rejected.
 *
 * @param PromiseInterface $promise
 *
 * @return bool
 */
function is_settled(PromiseInterface $promise)
{
    return $promise->getState() !== PromiseInterface::PENDING;
}

/**
 * @see Coroutine
 *
 * @param callable $generatorFn
 *
 * @return PromiseInterface
 */
function coroutine(callable $generatorFn)
{
    return new Coroutine($generatorFn);
}

--- NEW FILE: functions_include.php ---
<?php

// Don't redefine the functions if included multiple times.
if (!function_exists('GuzzleHttp\Promise\promise_for')) {
    require __DIR__ . '/functions.php';
}

--- NEW FILE: RejectedPromise.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * A promise that has been rejected.
 *
 * Thenning off of this promise will invoke the onRejected callback
 * immediately and ignore other callbacks.
 */
class RejectedPromise implements PromiseInterface
{
    private $reason;

    public function __construct($reason)
    {
        if (method_exists($reason, 'then')) {
            throw new \InvalidArgumentException(
                'You cannot create a RejectedPromise with a promise.');
        }

        $this->reason = $reason;
    }

    public function then(
        callable $onFulfilled = null,
        callable $onRejected = null
    ) {
        // If there's no onRejected callback then just return self.
        if (!$onRejected) {
            return $this;
        }

        $queue = queue();
        $reason = $this->reason;
        $p = new Promise([$queue, 'run']);
        $queue->add(static function () use ($p, $reason, $onRejected) {
            if ($p->getState() === self::PENDING) {
                try {
                    // Return a resolved promise if onRejected does not throw.
                    $p->resolve($onRejected($reason));
                } catch (\Throwable $e) {
                    // onRejected threw, so return a rejected promise.
                    $p->reject($e);
                } catch (\Exception $e) {
                    // onRejected threw, so return a rejected promise.
                    $p->reject($e);
                }
            }
        });

        return $p;
    }

    public function otherwise(callable $onRejected)
    {
        return $this->then(null, $onRejected);
    }

    public function wait($unwrap = true, $defaultDelivery = null)
    {
        if ($unwrap) {
            throw exception_for($this->reason);
        }
    }

    public function getState()
    {
        return self::REJECTED;
    }

    public function resolve($value)
    {
        throw new \LogicException("Cannot resolve a rejected promise");
    }

    public function reject($reason)
    {
        if ($reason !== $this->reason) {
            throw new \LogicException("Cannot reject a rejected promise");
        }
    }

    public function cancel()
    {
        // pass
    }
}

--- NEW FILE: Coroutine.php ---
<?php
namespace GuzzleHttp\Promise;

use Exception;
use Generator;
use Throwable;

/**
 * Creates a promise that is resolved using a generator that yields values or
 * promises (somewhat similar to C#'s async keyword).
 *
 * When called, the coroutine function will start an instance of the generator
 * and returns a promise that is fulfilled with its final yielded value.
 *
 * Control is returned back to the generator when the yielded promise settles.
 * This can lead to less verbose code when doing lots of sequential async calls
 * with minimal processing in between.
 *
 *     use GuzzleHttp\Promise;
 *
 *     function createPromise($value) {
 *         return new Promise\FulfilledPromise($value);
 *     }
 *
 *     $promise = Promise\coroutine(function () {
 *         $value = (yield createPromise('a'));
 *         try {
 *             $value = (yield createPromise($value . 'b'));
 *         } catch (\Exception $e) {
 *             // The promise was rejected.
 *         }
 *         yield $value . 'c';
 *     });
 *
 *     // Outputs "abc"
 *     $promise->then(function ($v) { echo $v; });
 *
 * @param callable $generatorFn Generator function to wrap into a promise.
 *
 * @return Promise
 * @link https://github.com/petkaantonov/bluebird/blob/master/API.md#generators inspiration
 */
final class Coroutine implements PromiseInterface
{
    /**
     * @var PromiseInterface|null
     */
    private $currentPromise;

    /**
     * @var Generator
     */
    private $generator;

    /**
     * @var Promise
     */
    private $result;

    public function __construct(callable $generatorFn)
    {
        $this->generator = $generatorFn();
        $this->result = new Promise(function () {
            while (isset($this->currentPromise)) {
                $this->currentPromise->wait();
            }
        });
        $this->nextCoroutine($this->generator->current());
    }

    public function then(
        callable $onFulfilled = null,
        callable $onRejected = null
    ) {
        return $this->result->then($onFulfilled, $onRejected);
    }

    public function otherwise(callable $onRejected)
    {
        return $this->result->otherwise($onRejected);
    }

    public function wait($unwrap = true)
    {
        return $this->result->wait($unwrap);
    }

    public function getState()
    {
        return $this->result->getState();
    }

    public function resolve($value)
    {
        $this->result->resolve($value);
    }

    public function reject($reason)
    {
        $this->result->reject($reason);
    }

    public function cancel()
    {
        $this->currentPromise->cancel();
        $this->result->cancel();
    }

    private function nextCoroutine($yielded)
    {
        $this->currentPromise = promise_for($yielded)
            ->then([$this, '_handleSuccess'], [$this, '_handleFailure']);
    }

    /**
     * @internal
     */
    public function _handleSuccess($value)
    {
        unset($this->currentPromise);
        try {
            $next = $this->generator->send($value);
            if ($this->generator->valid()) {
                $this->nextCoroutine($next);
            } else {
                $this->result->resolve($value);
            }
        } catch (Exception $exception) {
            $this->result->reject($exception);
        } catch (Throwable $throwable) {
            $this->result->reject($throwable);
        }
    }

    /**
     * @internal
     */
    public function _handleFailure($reason)
    {
        unset($this->currentPromise);
        try {
            $nextYield = $this->generator->throw(exception_for($reason));
            // The throw was caught, so keep iterating on the coroutine
            $this->nextCoroutine($nextYield);
        } catch (Exception $exception) {
            $this->result->reject($exception);
        } catch (Throwable $throwable) {
            $this->result->reject($throwable);
        }
    }
}

--- NEW FILE: CancellationException.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * Exception that is set as the reason for a promise that has been cancelled.
 */
class CancellationException extends RejectionException
{
}

--- NEW FILE: PromisorInterface.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * Interface used with classes that return a promise.
 */
interface PromisorInterface
{
    /**
     * Returns a promise.
     *
     * @return PromiseInterface
     */
    public function promise();
}

--- NEW FILE: PromiseInterface.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * A promise represents the eventual result of an asynchronous operation.
 *
 * The primary way of interacting with a promise is through its then method,
 * which registers callbacks to receive either a promise’s eventual value or
 * the reason why the promise cannot be fulfilled.
 *
 * @link https://promisesaplus.com/
 */
interface PromiseInterface
{
    const PENDING = 'pending';
    const FULFILLED = 'fulfilled';
    const REJECTED = 'rejected';

    /**
     * Appends fulfillment and rejection handlers to the promise, and returns
     * a new promise resolving to the return value of the called handler.
     *
     * @param callable $onFulfilled Invoked when the promise fulfills.
     * @param callable $onRejected  Invoked when the promise is rejected.
     *
     * @return PromiseInterface
     */
    public function then(
        callable $onFulfilled = null,
        callable $onRejected = null
    );

    /**
     * Appends a rejection handler callback to the promise, and returns a new
     * promise resolving to the return value of the callback if it is called,
     * or to its original fulfillment value if the promise is instead
     * fulfilled.
     *
     * @param callable $onRejected Invoked when the promise is rejected.
     *
     * @return PromiseInterface
     */
    public function otherwise(callable $onRejected);

    /**
     * Get the state of the promise ("pending", "rejected", or "fulfilled").
     *
     * The three states can be checked against the constants defined on
     * PromiseInterface: PENDING, FULFILLED, and REJECTED.
     *
     * @return string
     */
    public function getState();

    /**
     * Resolve the promise with the given value.
     *
     * @param mixed $value
     * @throws \RuntimeException if the promise is already resolved.
     */
    public function resolve($value);

    /**
     * Reject the promise with the given reason.
     *
     * @param mixed $reason
     * @throws \RuntimeException if the promise is already resolved.
     */
    public function reject($reason);

    /**
     * Cancels the promise if possible.
     *
     * @link https://github.com/promises-aplus/cancellation-spec/issues/7
     */
    public function cancel();

    /**
     * Waits until the promise completes if possible.
     *
     * Pass $unwrap as true to unwrap the result of the promise, either
     * returning the resolved value or throwing the rejected exception.
     *
     * If the promise cannot be waited on, then the promise will be rejected.
     *
     * @param bool $unwrap
     *
     * @return mixed
     * @throws \LogicException if the promise has no wait function or if the
     *                         promise does not settle after waiting.
     */
    public function wait($unwrap = true);
}

--- NEW FILE: RejectionException.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * A special exception that is thrown when waiting on a rejected promise.
 *
 * The reason value is available via the getReason() method.
 */
class RejectionException extends \RuntimeException
{
    /** @var mixed Rejection reason. */
    private $reason;

    /**
     * @param mixed $reason       Rejection reason.
     * @param string $description Optional description
     */
    public function __construct($reason, $description = null)
    {
        $this->reason = $reason;

        $message = 'The promise was rejected';

        if ($description) {
            $message .= ' with reason: ' . $description;
        } elseif (is_string($reason)
            || (is_object($reason) && method_exists($reason, '__toString'))
        ) {
            $message .= ' with reason: ' . $this->reason;
        } elseif ($reason instanceof \JsonSerializable) {
            $message .= ' with reason: '
                . json_encode($this->reason, JSON_PRETTY_PRINT);
        }

        parent::__construct($message);
    }

    /**
     * Returns the rejection reason.
     *
     * @return mixed
     */
    public function getReason()
    {
        return $this->reason;
    }
}

--- NEW FILE: FulfilledPromise.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * A promise that has been fulfilled.
 *
 * Thenning off of this promise will invoke the onFulfilled callback
 * immediately and ignore other callbacks.
 */
class FulfilledPromise implements PromiseInterface
{
    private $value;

    public function __construct($value)
    {
        if (method_exists($value, 'then')) {
            throw new \InvalidArgumentException(
                'You cannot create a FulfilledPromise with a promise.');
        }

        $this->value = $value;
    }

    public function then(
        callable $onFulfilled = null,
        callable $onRejected = null
    ) {
        // Return itself if there is no onFulfilled function.
        if (!$onFulfilled) {
            return $this;
        }

        $queue = queue();
        $p = new Promise([$queue, 'run']);
        $value = $this->value;
        $queue->add(static function () use ($p, $value, $onFulfilled) {
            if ($p->getState() === self::PENDING) {
                try {
                    $p->resolve($onFulfilled($value));
                } catch (\Throwable $e) {
                    $p->reject($e);
                } catch (\Exception $e) {
                    $p->reject($e);
                }
            }
        });

        return $p;
    }

    public function otherwise(callable $onRejected)
    {
        return $this->then(null, $onRejected);
    }

    public function wait($unwrap = true, $defaultDelivery = null)
    {
        return $unwrap ? $this->value : null;
    }

    public function getState()
    {
        return self::FULFILLED;
    }

    public function resolve($value)
    {
        if ($value !== $this->value) {
            throw new \LogicException("Cannot resolve a fulfilled promise");
        }
    }

    public function reject($reason)
    {
        throw new \LogicException("Cannot reject a fulfilled promise");
    }

    public function cancel()
    {
        // pass
    }
}

--- NEW FILE: TaskQueue.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * A task queue that executes tasks in a FIFO order.
 *
 * This task queue class is used to settle promises asynchronously and
 * maintains a constant stack size. You can use the task queue asynchronously
 * by calling the `run()` function of the global task queue in an event loop.
 *
 *     GuzzleHttp\Promise\queue()->run();
 */
class TaskQueue implements TaskQueueInterface
{
    private $enableShutdown = true;
    private $queue = [];

    public function __construct($withShutdown = true)
    {
        if ($withShutdown) {
            register_shutdown_function(function () {
                if ($this->enableShutdown) {
                    // Only run the tasks if an E_ERROR didn't occur.
                    $err = error_get_last();
                    if (!$err || ($err['type'] ^ E_ERROR)) {
                        $this->run();
                    }
                }
            });
        }
    }

    public function isEmpty()
    {
        return !$this->queue;
    }

    public function add(callable $task)
    {
        $this->queue[] = $task;
    }

    public function run()
    {
        /** @var callable $task */
        while ($task = array_shift($this->queue)) {
            $task();
        }
    }

    /**
     * The task queue will be run and exhausted by default when the process
     * exits IFF the exit is not the result of a PHP E_ERROR error.
     *
     * You can disable running the automatic shutdown of the queue by calling
     * this function. If you disable the task queue shutdown process, then you
     * MUST either run the task queue (as a result of running your event loop
     * or manually using the run() method) or wait on each outstanding promise.
     *
     * Note: This shutdown will occur before any destructors are triggered.
     */
    public function disableShutdown()
    {
        $this->enableShutdown = false;
    }
}

--- NEW FILE: AggregateException.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * Exception thrown when too many errors occur in the some() or any() methods.
 */
class AggregateException extends RejectionException
{
    public function __construct($msg, array $reasons)
    {
        parent::__construct(
            $reasons,
            sprintf('%s; %d rejected promises', $msg, count($reasons))
        );
    }
}

--- NEW FILE: TaskQueueInterface.php ---
<?php
namespace GuzzleHttp\Promise;

interface TaskQueueInterface
{
    /**
     * Returns true if the queue is empty.
     *
     * @return bool
     */
    public function isEmpty();

    /**
     * Adds a task to the queue that will be executed the next time run is
     * called.
     *
     * @param callable $task
     */
    public function add(callable $task);

    /**
     * Execute all of the pending task in the queue.
     */
    public function run();
}

--- NEW FILE: Promise.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * Promises/A+ implementation that avoids recursion when possible.
 *
 * @link https://promisesaplus.com/
 */
class Promise implements PromiseInterface
{
    private $state = self::PENDING;
    private $result;
    private $cancelFn;
    private $waitFn;
    private $waitList;
    private $handlers = [];

    /**
     * @param callable $waitFn   Fn that when invoked resolves the promise.
     * @param callable $cancelFn Fn that when invoked cancels the promise.
     */
    public function __construct(
        callable $waitFn = null,
        callable $cancelFn = null
    ) {
        $this->waitFn = $waitFn;
        $this->cancelFn = $cancelFn;
    }

    public function then(
        callable $onFulfilled = null,
        callable $onRejected = null
    ) {
        if ($this->state === self::PENDING) {
            $p = new Promise(null, [$this, 'cancel']);
            $this->handlers[] = [$p, $onFulfilled, $onRejected];
            $p->waitList = $this->waitList;
            $p->waitList[] = $this;
            return $p;
        }

        // Return a fulfilled promise and immediately invoke any callbacks.
        if ($this->state === self::FULFILLED) {
            return $onFulfilled
                ? promise_for($this->result)->then($onFulfilled)
                : promise_for($this->result);
        }

        // It's either cancelled or rejected, so return a rejected promise
        // and immediately invoke any callbacks.
        $rejection = rejection_for($this->result);
        return $onRejected ? $rejection->then(null, $onRejected) : $rejection;
    }

    public function otherwise(callable $onRejected)
    {
        return $this->then(null, $onRejected);
    }

    public function wait($unwrap = true)
    {
        $this->waitIfPending();

        $inner = $this->result instanceof PromiseInterface
            ? $this->result->wait($unwrap)
            : $this->result;

        if ($unwrap) {
            if ($this->result instanceof PromiseInterface
                || $this->state === self::FULFILLED
            ) {
                return $inner;
            } else {
                // It's rejected so "unwrap" and throw an exception.
                throw exception_for($inner);
            }
        }
    }

    public function getState()
    {
        return $this->state;
    }

    public function cancel()
    {
        if ($this->state !== self::PENDING) {
            return;
        }

        $this->waitFn = $this->waitList = null;

        if ($this->cancelFn) {
            $fn = $this->cancelFn;
            $this->cancelFn = null;
            try {
                $fn();
            } catch (\Throwable $e) {
                $this->reject($e);
            } catch (\Exception $e) {
                $this->reject($e);
            }
        }

        // Reject the promise only if it wasn't rejected in a then callback.
        if ($this->state === self::PENDING) {
            $this->reject(new CancellationException('Promise has been cancelled'));
        }
    }

    public function resolve($value)
    {
        $this->settle(self::FULFILLED, $value);
    }

    public function reject($reason)
    {
        $this->settle(self::REJECTED, $reason);
    }

    private function settle($state, $value)
    {
        if ($this->state !== self::PENDING) {
            // Ignore calls with the same resolution.
            if ($state === $this->state && $value === $this->result) {
                return;
            }
            throw $this->state === $state
                ? new \LogicException("The promise is already {$state}.")
                : new \LogicException("Cannot change a {$this->state} promise to {$state}");
        }

        if ($value === $this) {
            throw new \LogicException('Cannot fulfill or reject a promise with itself');
        }

        // Clear out the state of the promise but stash the handlers.
        $this->state = $state;
        $this->result = $value;
        $handlers = $this->handlers;
        $this->handlers = null;
        $this->waitList = $this->waitFn = null;
        $this->cancelFn = null;

        if (!$handlers) {
            return;
        }

        // If the value was not a settled promise or a thenable, then resolve
        // it in the task queue using the correct ID.
        if (!method_exists($value, 'then')) {
            $id = $state === self::FULFILLED ? 1 : 2;
            // It's a success, so resolve the handlers in the queue.
            queue()->add(static function () use ($id, $value, $handlers) {
                foreach ($handlers as $handler) {
                    self::callHandler($id, $value, $handler);
                }
            });
        } elseif ($value instanceof Promise
            && $value->getState() === self::PENDING
        ) {
            // We can just merge our handlers onto the next promise.
            $value->handlers = array_merge($value->handlers, $handlers);
        } else {
            // Resolve the handlers when the forwarded promise is resolved.
            $value->then(
                static function ($value) use ($handlers) {
                    foreach ($handlers as $handler) {
                        self::callHandler(1, $value, $handler);
                    }
                },
                static function ($reason) use ($handlers) {
                    foreach ($handlers as $handler) {
                        self::callHandler(2, $reason, $handler);
                    }
                }
            );
        }
    }

    /**
     * Call a stack of handlers using a specific callback index and value.
     *
     * @param int   $index   1 (resolve) or 2 (reject).
     * @param mixed $value   Value to pass to the callback.
     * @param array $handler Array of handler data (promise and callbacks).
     *
     * @return array Returns the next group to resolve.
     */
    private static function callHandler($index, $value, array $handler)
    {
        /** @var PromiseInterface $promise */
        $promise = $handler[0];

        // The promise may have been cancelled or resolved before placing
        // this thunk in the queue.
        if ($promise->getState() !== self::PENDING) {
            return;
        }

        try {
            if (isset($handler[$index])) {
                $promise->resolve($handler[$index]($value));
            } elseif ($index === 1) {
                // Forward resolution values as-is.
                $promise->resolve($value);
            } else {
                // Forward rejections down the chain.
                $promise->reject($value);
            }
        } catch (\Throwable $reason) {
            $promise->reject($reason);
        } catch (\Exception $reason) {
            $promise->reject($reason);
        }
    }

    private function waitIfPending()
    {
        if ($this->state !== self::PENDING) {
            return;
        } elseif ($this->waitFn) {
            $this->invokeWaitFn();
        } elseif ($this->waitList) {
            $this->invokeWaitList();
        } else {
            // If there's not wait function, then reject the promise.
            $this->reject('Cannot wait on a promise that has '
                . 'no internal wait function. You must provide a wait '
                . 'function when constructing the promise to be able to '
                . 'wait on a promise.');
        }

        queue()->run();

        if ($this->state === self::PENDING) {
            $this->reject('Invoking the wait callback did not resolve the promise');
        }
    }

    private function invokeWaitFn()
    {
        try {
            $wfn = $this->waitFn;
            $this->waitFn = null;
            $wfn(true);
        } catch (\Exception $reason) {
            if ($this->state === self::PENDING) {
                // The promise has not been resolved yet, so reject the promise
                // with the exception.
                $this->reject($reason);
            } else {
                // The promise was already resolved, so there's a problem in
                // the application.
                throw $reason;
            }
        }
    }

    private function invokeWaitList()
    {
        $waitList = $this->waitList;
        $this->waitList = null;

        foreach ($waitList as $result) {
            while (true) {
                $result->waitIfPending();

                if ($result->result instanceof Promise) {
                    $result = $result->result;
                } else {
                    if ($result->result instanceof PromiseInterface) {
                        $result->result->wait(false);
                    }
                    break;
                }
            }
        }
    }
}

--- NEW FILE: EachPromise.php ---
<?php
namespace GuzzleHttp\Promise;

/**
 * Represents a promise that iterates over many promises and invokes
 * side-effect functions in the process.
 */
class EachPromise implements PromisorInterface
{
    private $pending = [];

    /** @var \Iterator */
    private $iterable;

    /** @var callable|int */
    private $concurrency;

    /** @var callable */
    private $onFulfilled;

    /** @var callable */
    private $onRejected;

    /** @var Promise */
    private $aggregate;

    /** @var bool */
    private $mutex;

    /**
     * Configuration hash can include the following key value pairs:
     *
     * - fulfilled: (callable) Invoked when a promise fulfills. The function
     *   is invoked with three arguments: the fulfillment value, the index
     *   position from the iterable list of the promise, and the aggregate
     *   promise that manages all of the promises. The aggregate promise may
     *   be resolved from within the callback to short-circuit the promise.
     * - rejected: (callable) Invoked when a promise is rejected. The
     *   function is invoked with three arguments: the rejection reason, the
     *   index position from the iterable list of the promise, and the
     *   aggregate promise that manages all of the promises. The aggregate
     *   promise may be resolved from within the callback to short-circuit
     *   the promise.
     * - concurrency: (integer) Pass this configuration option to limit the
     *   allowed number of outstanding concurrently executing promises,
     *   creating a capped pool of promises. There is no limit by default.
     *
     * @param mixed    $iterable Promises or values to iterate.
     * @param array    $config   Configuration options
     */
    public function __construct($iterable, array $config = [])
    {
        $this->iterable = iter_for($iterable);

        if (isset($config['concurrency'])) {
            $this->concurrency = $config['concurrency'];
        }

        if (isset($config['fulfilled'])) {
            $this->onFulfilled = $config['fulfilled'];
        }

        if (isset($config['rejected'])) {
            $this->onRejected = $config['rejected'];
        }
    }

    public function promise()
    {
        if ($this->aggregate) {
            return $this->aggregate;
        }

        try {
            $this->createPromise();
            $this->iterable->rewind();
            $this->refillPending();
        } catch (\Throwable $e) {
            $this->aggregate->reject($e);
        } catch (\Exception $e) {
            $this->aggregate->reject($e);
        }

        return $this->aggregate;
    }

    private function createPromise()
    {
        $this->mutex = false;
        $this->aggregate = new Promise(function () {
            reset($this->pending);
            if (empty($this->pending) && !$this->iterable->valid()) {
                $this->aggregate->resolve(null);
                return;
            }

            // Consume a potentially fluctuating list of promises while
            // ensuring that indexes are maintained (precluding array_shift).
            while ($promise = current($this->pending)) {
                next($this->pending);
                $promise->wait();
                if ($this->aggregate->getState() !== PromiseInterface::PENDING) {
                    return;
                }
            }
        });

        // Clear the references when the promise is resolved.
        $clearFn = function () {
            $this->iterable = $this->concurrency = $this->pending = null;
            $this->onFulfilled = $this->onRejected = null;
        };

        $this->aggregate->then($clearFn, $clearFn);
    }

    private function refillPending()
    {
        if (!$this->concurrency) {
            // Add all pending promises.
            while ($this->addPending() && $this->advanceIterator());
            return;
        }

        // Add only up to N pending promises.
        $concurrency = is_callable($this->concurrency)
            ? call_user_func($this->concurrency, count($this->pending))
            : $this->concurrency;
        $concurrency = max($concurrency - count($this->pending), 0);
        // Concurrency may be set to 0 to disallow new promises.
        if (!$concurrency) {
            return;
        }
        // Add the first pending promise.
        $this->addPending();
        // Note this is special handling for concurrency=1 so that we do
        // not advance the iterator after adding the first promise. This
        // helps work around issues with generators that might not have the
        // next value to yield until promise callbacks are called.
        while (--$concurrency
            && $this->advanceIterator()
            && $this->addPending());
    }

    private function addPending()
    {
        if (!$this->iterable || !$this->iterable->valid()) {
            return false;
        }

        $promise = promise_for($this->iterable->current());
        $idx = $this->iterable->key();

        $this->pending[$idx] = $promise->then(
            function ($value) use ($idx) {
                if ($this->onFulfilled) {
                    call_user_func(
                        $this->onFulfilled, $value, $idx, $this->aggregate
                    );
                }
                $this->step($idx);
            },
            function ($reason) use ($idx) {
                if ($this->onRejected) {
                    call_user_func(
                        $this->onRejected, $reason, $idx, $this->aggregate
                    );
                }
                $this->step($idx);
            }
        );

        return true;
    }

    private function advanceIterator()
    {
        // Place a lock on the iterator so that we ensure to not recurse,
        // preventing fatal generator errors.
        if ($this->mutex) {
            return false;
        }

        $this->mutex = true;

        try {
            $this->iterable->next();
            $this->mutex = false;
            return true;
        } catch (\Throwable $e) {
            $this->aggregate->reject($e);
            $this->mutex = false;
            return false;
        } catch (\Exception $e) {
            $this->aggregate->reject($e);
            $this->mutex = false;
            return false;
        }
    }

    private function step($idx)
    {
        // If the promise was already resolved, then ignore this step.
        if ($this->aggregate->getState() !== PromiseInterface::PENDING) {
            return;
        }

        unset($this->pending[$idx]);

        // Only refill pending promises if we are not locked, preventing the
        // EachPromise to recursively invoke the provided iterator, which
        // cause a fatal error: "Cannot resume an already running generator"
        if ($this->advanceIterator() && !$this->checkIfFinished()) {
            // Add more pending promises if possible.
            $this->refillPending();
        }
    }

    private function checkIfFinished()
    {
        if (!$this->pending && !$this->iterable->valid()) {
            // Resolve the promise if there's nothing left to do.
            $this->aggregate->resolve(null);
            return true;
        }

        return false;
    }
}