ObservableFactoryWrapper should convert promise to observable

Author: WyriHaximus

src/ObservableFactoryWrapper.php

@@ -4,6 +4,9 @@
 
 namespace Rx;
 
+use React\Promise\PromiseInterface;
+use Rx\React\Promise;
+
 final class ObservableFactoryWrapper
 {
     private $selector;
@@ -17,6 +20,10 @@ public function __invoke(): Observable
     {
         $result = call_user_func_array($this->selector, func_get_args());
 
+        if ($result instanceof PromiseInterface) {
+            $result = Promise::toObservable($result);
+        }
+
         if (!$result instanceof ObservableInterface) {
             $reflectCallable = new \ReflectionFunction($this->selector);
             throw new \Exception("You must return an Observable or Promise in {$reflectCallable->getFileName()} on line {$reflectCallable->getStartLine()}\n");