From 0b381dbe1d50a40f12115ea97b9bd0dd5a04b075 Mon Sep 17 00:00:00 2001
From: Christian Flothmann <christian.flothmann@sensiolabs.de>
Date: Wed, 26 Jun 2019 17:59:51 +0200
Subject: [PATCH] improve error messages in the event dispatcher

---
 .../EventDispatcher/EventDispatcher.php       | 10 +++----
 .../LegacyEventDispatcherProxy.php            | 12 ++++----
 .../Tests/EventDispatcherTest.php             | 27 +++++++++++++++++
 .../Tests/LegacyEventDispatcherTest.php       | 30 +++++++++++++++++++
 4 files changed, 66 insertions(+), 13 deletions(-)

diff --git a/src/Symfony/Component/EventDispatcher/EventDispatcher.php b/src/Symfony/Component/EventDispatcher/EventDispatcher.php
index 304caec1d1..a5f0b7eda5 100644
--- a/src/Symfony/Component/EventDispatcher/EventDispatcher.php
+++ b/src/Symfony/Component/EventDispatcher/EventDispatcher.php
@@ -54,15 +54,13 @@ class EventDispatcher implements EventDispatcherInterface
 
         if (\is_object($event)) {
             $eventName = $eventName ?? \get_class($event);
-        } else {
-            @trigger_error(sprintf('Calling the "%s::dispatch()" method with the event name as first argument is deprecated since Symfony 4.3, pass it second and provide the event object first instead.', EventDispatcherInterface::class), E_USER_DEPRECATED);
+        } elseif (\is_string($event) && (null === $eventName || $eventName instanceof Event)) {
+            @trigger_error(sprintf('Calling the "%s::dispatch()" method with the event name as the first argument is deprecated since Symfony 4.3, pass it as the second argument and provide the event object as the first argument instead.', EventDispatcherInterface::class), E_USER_DEPRECATED);
             $swap = $event;
             $event = $eventName ?? new Event();
             $eventName = $swap;
-
-            if (!$event instanceof Event) {
-                throw new \TypeError(sprintf('Argument 1 passed to "%s::dispatch()" must be an instance of %s, %s given.', EventDispatcherInterface::class, Event::class, \is_object($event) ? \get_class($event) : \gettype($event)));
-            }
+        } else {
+            throw new \TypeError(sprintf('Argument 1 passed to "%s::dispatch()" must be an object, %s given.', EventDispatcherInterface::class, \is_object($event) ? \get_class($event) : \gettype($event)));
         }
 
         if (null !== $this->optimized && null !== $eventName) {
diff --git a/src/Symfony/Component/EventDispatcher/LegacyEventDispatcherProxy.php b/src/Symfony/Component/EventDispatcher/LegacyEventDispatcherProxy.php
index 534eec98a5..afa3e988d0 100644
--- a/src/Symfony/Component/EventDispatcher/LegacyEventDispatcherProxy.php
+++ b/src/Symfony/Component/EventDispatcher/LegacyEventDispatcherProxy.php
@@ -16,7 +16,7 @@ use Symfony\Contracts\EventDispatcher\Event as ContractsEvent;
 use Symfony\Contracts\EventDispatcher\EventDispatcherInterface as ContractsEventDispatcherInterface;
 
 /**
- * An helper class to provide BC/FC with the legacy signature of EventDispatcherInterface::dispatch().
+ * A helper class to provide BC/FC with the legacy signature of EventDispatcherInterface::dispatch().
  *
  * This class should be deprecated in Symfony 5.1
  *
@@ -57,15 +57,13 @@ final class LegacyEventDispatcherProxy implements EventDispatcherInterface
 
         if (\is_object($event)) {
             $eventName = $eventName ?? \get_class($event);
-        } else {
-            @trigger_error(sprintf('Calling the "%s::dispatch()" method with the event name as first argument is deprecated since Symfony 4.3, pass it second and provide the event object first instead.', ContractsEventDispatcherInterface::class), E_USER_DEPRECATED);
+        } elseif (\is_string($event) && (null === $eventName || $eventName instanceof Event)) {
+            @trigger_error(sprintf('Calling the "%s::dispatch()" method with the event name as the first argument is deprecated since Symfony 4.3, pass it as the second argument and provide the event object as the first argument instead.', ContractsEventDispatcherInterface::class), E_USER_DEPRECATED);
             $swap = $event;
             $event = $eventName ?? new Event();
             $eventName = $swap;
-
-            if (!$event instanceof Event) {
-                throw new \TypeError(sprintf('Argument 1 passed to "%s::dispatch()" must be an instance of %s, %s given.', ContractsEventDispatcherInterface::class, Event::class, \is_object($event) ? \get_class($event) : \gettype($event)));
-            }
+        } else {
+            throw new \TypeError(sprintf('Argument 1 passed to "%s::dispatch()" must be an object, %s given.', ContractsEventDispatcherInterface::class, \is_object($event) ? \get_class($event) : \gettype($event)));
         }
 
         $listeners = $this->getListeners($eventName);
diff --git a/src/Symfony/Component/EventDispatcher/Tests/EventDispatcherTest.php b/src/Symfony/Component/EventDispatcher/Tests/EventDispatcherTest.php
index e89f78cda8..658a941239 100644
--- a/src/Symfony/Component/EventDispatcher/Tests/EventDispatcherTest.php
+++ b/src/Symfony/Component/EventDispatcher/Tests/EventDispatcherTest.php
@@ -412,6 +412,33 @@ class EventDispatcherTest extends TestCase
 
         $this->assertTrue($testLoaded);
     }
+
+    /**
+     * @group legacy
+     * @expectedDeprecation Calling the "Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch()" method with the event name as the first argument is deprecated since Symfony 4.3, pass it as the second argument and provide the event object as the first argument instead.
+     */
+    public function testLegacySignatureWithoutEvent()
+    {
+        $this->dispatcher->dispatch('foo');
+    }
+
+    /**
+     * @group legacy
+     * @expectedDeprecation Calling the "Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch()" method with the event name as the first argument is deprecated since Symfony 4.3, pass it as the second argument and provide the event object as the first argument instead.
+     */
+    public function testLegacySignatureWithEvent()
+    {
+        $this->dispatcher->dispatch('foo', new Event());
+    }
+
+    /**
+     * @expectedException \TypeError
+     * @expectedExceptionMessage Argument 1 passed to "Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch()" must be an object, string given.
+     */
+    public function testLegacySignatureWithNewEventObject()
+    {
+        $this->dispatcher->dispatch('foo', new ContractsEvent());
+    }
 }
 
 class CallableClass
diff --git a/src/Symfony/Component/EventDispatcher/Tests/LegacyEventDispatcherTest.php b/src/Symfony/Component/EventDispatcher/Tests/LegacyEventDispatcherTest.php
index 49aa2f9ff3..ffa767cf8b 100644
--- a/src/Symfony/Component/EventDispatcher/Tests/LegacyEventDispatcherTest.php
+++ b/src/Symfony/Component/EventDispatcher/Tests/LegacyEventDispatcherTest.php
@@ -14,12 +14,42 @@ namespace Symfony\Component\EventDispatcher\Tests;
 use Symfony\Component\EventDispatcher\Event;
 use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Component\EventDispatcher\LegacyEventDispatcherProxy;
+use Symfony\Contracts\EventDispatcher\Event as ContractsEvent;
 
 /**
  * @group legacy
  */
 class LegacyEventDispatcherTest extends EventDispatcherTest
 {
+    /**
+     * @group legacy
+     * @expectedDeprecation The signature of the "Symfony\Component\EventDispatcher\Tests\TestLegacyEventDispatcher::dispatch()" method should be updated to "dispatch($event, string $eventName = null)", not doing so is deprecated since Symfony 4.3.
+     * @expectedDeprecation Calling the "Symfony\Contracts\EventDispatcher\EventDispatcherInterface::dispatch()" method with the event name as the first argument is deprecated since Symfony 4.3, pass it as the second argument and provide the event object as the first argument instead.
+     */
+    public function testLegacySignatureWithoutEvent()
+    {
+        $this->createEventDispatcher()->dispatch('foo');
+    }
+
+    /**
+     * @group legacy
+     * @expectedDeprecation The signature of the "Symfony\Component\EventDispatcher\Tests\TestLegacyEventDispatcher::dispatch()" method should be updated to "dispatch($event, string $eventName = null)", not doing so is deprecated since Symfony 4.3.
+     * @expectedDeprecation Calling the "Symfony\Contracts\EventDispatcher\EventDispatcherInterface::dispatch()" method with the event name as the first argument is deprecated since Symfony 4.3, pass it as the second argument and provide the event object as the first argument instead.
+     */
+    public function testLegacySignatureWithEvent()
+    {
+        $this->createEventDispatcher()->dispatch('foo', new Event());
+    }
+
+    /**
+     * @expectedException \TypeError
+     * @expectedExceptionMessage Argument 1 passed to "Symfony\Contracts\EventDispatcher\EventDispatcherInterface::dispatch()" must be an object, string given.
+     */
+    public function testLegacySignatureWithNewEventObject()
+    {
+        $this->createEventDispatcher()->dispatch('foo', new ContractsEvent());
+    }
+
     protected function createEventDispatcher()
     {
         return LegacyEventDispatcherProxy::decorate(new TestLegacyEventDispatcher());