Viewing file:  Promise.php (5.9 KB) -rwxrwxr-x
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
<?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;
$this->call($resolver);
}
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));
}
$this->requiredCancelRequests++;
return new static($this->resolver($onFulfilled, $onRejected, $onProgress), function () {
if (++$this->cancelRequests < $this->requiredCancelRequests) {
return;
}
$this->cancel();
});
}
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[] = function (ExtendedPromiseInterface $promise) use ($onFulfilled, $onRejected) {
$promise
->done($onFulfilled, $onRejected);
};
if ($onProgress) {
$this->progressHandlers[] = $onProgress;
}
}
public function otherwise(callable $onRejected)
{
return $this->then(null, function ($reason) use ($onRejected) {
if (!_checkTypehint($onRejected, $reason)) {
return new RejectedPromise($reason);
}
return $onRejected($reason);
});
}
public function always(callable $onFulfilledOrRejected)
{
return $this->then(function ($value) use ($onFulfilledOrRejected) {
return resolve($onFulfilledOrRejected())->then(function () use ($value) {
return $value;
});
}, function ($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) {
$progressHandler = function ($update) use ($notify, $onProgress) {
try {
$notify($onProgress($update));
} catch (\Throwable $e) {
$notify($e);
} catch (\Exception $e) {
$notify($e);
}
};
} else {
$progressHandler = $notify;
}
$this->handlers[] = function (ExtendedPromiseInterface $promise) use ($onFulfilled, $onRejected, $resolve, $reject, $progressHandler) {
$promise
->then($onFulfilled, $onRejected)
->done($resolve, $reject, $progressHandler);
};
$this->progressHandlers[] = $progressHandler;
};
}
private function resolve($value = null)
{
if (null !== $this->result) {
return;
}
$this->settle(resolve($value));
}
private function reject($reason = null)
{
if (null !== $this->result) {
return;
}
$this->settle(reject($reason));
}
private function notify($update = null)
{
if (null !== $this->result) {
return;
}
foreach ($this->progressHandlers as $handler) {
$handler($update);
}
}
private function settle(ExtendedPromiseInterface $promise)
{
$promise = $this->unwrap($promise);
$handlers = $this->handlers;
$this->progressHandlers = $this->handlers = [];
$this->result = $promise;
foreach ($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 = $promise->promise();
}
if ($promise === $this) {
return new RejectedPromise(
new \LogicException('Cannot resolve a promise with itself.')
);
}
return $promise;
}
private function call(callable $callback)
{
try {
$callback(
function ($value = null) {
$this->resolve($value);
},
function ($reason = null) {
$this->reject($reason);
},
function ($update = null) {
$this->notify($update);
}
);
} catch (\Throwable $e) {
$this->reject($e);
} catch (\Exception $e) {
$this->reject($e);
}
}
}
|