minor #29525 [Messenger] Make MessengerPass less strict when auto-register handlers (nicholasruunu)

This PR was merged into the 4.3-dev branch.

Discussion
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[Messenger] Make MessengerPass less strict when auto-register handlers

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT
| Doc PR        | not needed

This allows you to auto-register handlers that have more than one argument, which is useful when having custom middleware to pass more parameters.

#symfonyconhackday2018

Commits
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49ab2cd9d9 Make MessengerPass less strict when auto-register handlers

Author: sroze

DependencyInjection/MessengerPass.php

@@ -201,11 +201,11 @@ private function guessHandledClasses(\ReflectionClass $handlerClass, string $ser
             throw new RuntimeException(sprintf('Invalid handler service "%s": class "%s" must have an "__invoke()" method.', $serviceId, $handlerClass->getName()));
         }
 
-        $parameters = $method->getParameters();
-        if (1 !== \count($parameters)) {
-            throw new RuntimeException(sprintf('Invalid handler service "%s": method "%s::__invoke()" must have exactly one argument corresponding to the message it handles.', $serviceId, $handlerClass->getName()));
+        if (0 === $method->getNumberOfRequiredParameters()) {
+            throw new RuntimeException(sprintf('Invalid handler service "%s": method "%s::__invoke()" requires at least one argument, first one being the message it handles.', $serviceId, $handlerClass->getName()));
         }
 
+        $parameters = $method->getParameters();
         if (!$type = $parameters[0]->getType()) {
             throw new RuntimeException(sprintf('Invalid handler service "%s": argument "$%s" of method "%s::__invoke()" must have a type-hint corresponding to the message class it handles.', $serviceId, $parameters[0]->getName(), $handlerClass->getName()));
         }

Tests/DependencyInjection/MessengerPassTest.php

@@ -405,7 +405,7 @@ public function testNotInvokableHandler()
 
     /**
      * @expectedException \Symfony\Component\DependencyInjection\Exception\RuntimeException
-     * @expectedExceptionMessage Invalid handler service "Symfony\Component\Messenger\Tests\DependencyInjection\MissingArgumentHandler": method "Symfony\Component\Messenger\Tests\DependencyInjection\MissingArgumentHandler::__invoke()" must have exactly one argument corresponding to the message it handles.
+     * @expectedExceptionMessage Invalid handler service "Symfony\Component\Messenger\Tests\DependencyInjection\MissingArgumentHandler": method "Symfony\Component\Messenger\Tests\DependencyInjection\MissingArgumentHandler::__invoke()" requires at least one argument, first one being the message it handles.
      */
     public function testMissingArgumentHandler()
     {