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-rw-r--r--vendor/react/promise/src/Promise.php256
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diff --git a/vendor/react/promise/src/Promise.php b/vendor/react/promise/src/Promise.php
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+++ b/vendor/react/promise/src/Promise.php
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+<?php
+
+namespace React\Promise;
+
+class Promise implements ExtendedPromiseInterface, CancellablePromiseInterface
+{
+ private $canceller;
+ private $result;
+
+ private $handlers = [];
+ private $progressHandlers = [];
+
+ private $requiredCancelRequests = 0;
+ private $cancelRequests = 0;
+
+ public function __construct(callable $resolver, callable $canceller = null)
+ {
+ $this->canceller = $canceller;
+
+ // Explicitly overwrite arguments with null values before invoking
+ // resolver function. This ensure that these arguments do not show up
+ // in the stack trace in PHP 7+ only.
+ $cb = $resolver;
+ $resolver = $canceller = null;
+ $this->call($cb);
+ }
+
+ public function then(callable $onFulfilled = null, callable $onRejected = null, callable $onProgress = null)
+ {
+ if (null !== $this->result) {
+ return $this->result->then($onFulfilled, $onRejected, $onProgress);
+ }
+
+ if (null === $this->canceller) {
+ return new static($this->resolver($onFulfilled, $onRejected, $onProgress));
+ }
+
+ // This promise has a canceller, so we create a new child promise which
+ // has a canceller that invokes the parent canceller if all other
+ // followers are also cancelled. We keep a reference to this promise
+ // instance for the static canceller function and clear this to avoid
+ // keeping a cyclic reference between parent and follower.
+ $parent = $this;
+ ++$parent->requiredCancelRequests;
+
+ return new static(
+ $this->resolver($onFulfilled, $onRejected, $onProgress),
+ static function () use (&$parent) {
+ if (++$parent->cancelRequests >= $parent->requiredCancelRequests) {
+ $parent->cancel();
+ }
+
+ $parent = null;
+ }
+ );
+ }
+
+ public function done(callable $onFulfilled = null, callable $onRejected = null, callable $onProgress = null)
+ {
+ if (null !== $this->result) {
+ return $this->result->done($onFulfilled, $onRejected, $onProgress);
+ }
+
+ $this->handlers[] = static function (ExtendedPromiseInterface $promise) use ($onFulfilled, $onRejected) {
+ $promise
+ ->done($onFulfilled, $onRejected);
+ };
+
+ if ($onProgress) {
+ $this->progressHandlers[] = $onProgress;
+ }
+ }
+
+ public function otherwise(callable $onRejected)
+ {
+ return $this->then(null, static function ($reason) use ($onRejected) {
+ if (!_checkTypehint($onRejected, $reason)) {
+ return new RejectedPromise($reason);
+ }
+
+ return $onRejected($reason);
+ });
+ }
+
+ public function always(callable $onFulfilledOrRejected)
+ {
+ return $this->then(static function ($value) use ($onFulfilledOrRejected) {
+ return resolve($onFulfilledOrRejected())->then(function () use ($value) {
+ return $value;
+ });
+ }, static function ($reason) use ($onFulfilledOrRejected) {
+ return resolve($onFulfilledOrRejected())->then(function () use ($reason) {
+ return new RejectedPromise($reason);
+ });
+ });
+ }
+
+ public function progress(callable $onProgress)
+ {
+ return $this->then(null, null, $onProgress);
+ }
+
+ public function cancel()
+ {
+ if (null === $this->canceller || null !== $this->result) {
+ return;
+ }
+
+ $canceller = $this->canceller;
+ $this->canceller = null;
+
+ $this->call($canceller);
+ }
+
+ private function resolver(callable $onFulfilled = null, callable $onRejected = null, callable $onProgress = null)
+ {
+ return function ($resolve, $reject, $notify) use ($onFulfilled, $onRejected, $onProgress) {
+ if ($onProgress) {
+ $progressHandler = static function ($update) use ($notify, $onProgress) {
+ try {
+ $notify($onProgress($update));
+ } catch (\Throwable $e) {
+ $notify($e);
+ } catch (\Exception $e) {
+ $notify($e);
+ }
+ };
+ } else {
+ $progressHandler = $notify;
+ }
+
+ $this->handlers[] = static function (ExtendedPromiseInterface $promise) use ($onFulfilled, $onRejected, $resolve, $reject, $progressHandler) {
+ $promise
+ ->then($onFulfilled, $onRejected)
+ ->done($resolve, $reject, $progressHandler);
+ };
+
+ $this->progressHandlers[] = $progressHandler;
+ };
+ }
+
+ private function reject($reason = null)
+ {
+ if (null !== $this->result) {
+ return;
+ }
+
+ $this->settle(reject($reason));
+ }
+
+ private function settle(ExtendedPromiseInterface $promise)
+ {
+ $promise = $this->unwrap($promise);
+
+ if ($promise === $this) {
+ $promise = new RejectedPromise(
+ new \LogicException('Cannot resolve a promise with itself.')
+ );
+ }
+
+ $handlers = $this->handlers;
+
+ $this->progressHandlers = $this->handlers = [];
+ $this->result = $promise;
+ $this->canceller = null;
+
+ foreach ($handlers as $handler) {
+ $handler($promise);
+ }
+ }
+
+ private function unwrap($promise)
+ {
+ $promise = $this->extract($promise);
+
+ while ($promise instanceof self && null !== $promise->result) {
+ $promise = $this->extract($promise->result);
+ }
+
+ return $promise;
+ }
+
+ private function extract($promise)
+ {
+ if ($promise instanceof LazyPromise) {
+ $promise = $promise->promise();
+ }
+
+ return $promise;
+ }
+
+ private function call(callable $cb)
+ {
+ // Explicitly overwrite argument with null value. This ensure that this
+ // argument does not show up in the stack trace in PHP 7+ only.
+ $callback = $cb;
+ $cb = null;
+
+ // Use reflection to inspect number of arguments expected by this callback.
+ // We did some careful benchmarking here: Using reflection to avoid unneeded
+ // function arguments is actually faster than blindly passing them.
+ // Also, this helps avoiding unnecessary function arguments in the call stack
+ // if the callback creates an Exception (creating garbage cycles).
+ if (\is_array($callback)) {
+ $ref = new \ReflectionMethod($callback[0], $callback[1]);
+ } elseif (\is_object($callback) && !$callback instanceof \Closure) {
+ $ref = new \ReflectionMethod($callback, '__invoke');
+ } else {
+ $ref = new \ReflectionFunction($callback);
+ }
+ $args = $ref->getNumberOfParameters();
+
+ try {
+ if ($args === 0) {
+ $callback();
+ } else {
+ // Keep references to this promise instance for the static resolve/reject functions.
+ // By using static callbacks that are not bound to this instance
+ // and passing the target promise instance by reference, we can
+ // still execute its resolving logic and still clear this
+ // reference when settling the promise. This helps avoiding
+ // garbage cycles if any callback creates an Exception.
+ // These assumptions are covered by the test suite, so if you ever feel like
+ // refactoring this, go ahead, any alternative suggestions are welcome!
+ $target =& $this;
+ $progressHandlers =& $this->progressHandlers;
+
+ $callback(
+ static function ($value = null) use (&$target) {
+ if ($target !== null) {
+ $target->settle(resolve($value));
+ $target = null;
+ }
+ },
+ static function ($reason = null) use (&$target) {
+ if ($target !== null) {
+ $target->reject($reason);
+ $target = null;
+ }
+ },
+ static function ($update = null) use (&$progressHandlers) {
+ foreach ($progressHandlers as $handler) {
+ $handler($update);
+ }
+ }
+ );
+ }
+ } catch (\Throwable $e) {
+ $target = null;
+ $this->reject($e);
+ } catch (\Exception $e) {
+ $target = null;
+ $this->reject($e);
+ }
+ }
+}