[5.4] Conditional broadcasting

src/Illuminate/Events/Dispatcher.php

@@ -242,7 +242,9 @@ protected function parseEventAndPayload($event, $payload)
      */
     protected function shouldBroadcast(array $payload)
     {
-        return isset($payload[0]) && $payload[0] instanceof ShouldBroadcast;
+        return isset($payload[0]) &&
+               $payload[0] instanceof ShouldBroadcast &&
+               $this->checkBroadcastCondition($payload[0]);
     }
 
     /**
@@ -546,4 +548,20 @@ public function setQueueResolver(callable $resolver)
 
         return $this;
     }
+
+    /**
+     * Check if event should be broadcasted by condition.
+     *
+     * @param $event
+     *
+     * @return bool
+     */
+    protected function checkBroadcastCondition($event)
+    {
+        if (method_exists($event, 'broadcastWhen')) {
+            return $event->broadcastWhen();
+        }
+
+        return true;
+    }
 }

tests/Events/EventsDispatcherTest.php

@@ -5,6 +5,7 @@
 use Mockery as m;
 use PHPUnit\Framework\TestCase;
 use Illuminate\Events\Dispatcher;
+use Illuminate\Contracts\Broadcasting\ShouldBroadcast;
 
 class EventsDispatcherTest extends TestCase
 {
@@ -239,6 +240,28 @@ public function testBothClassesAndInterfacesWork()
         $this->assertSame('fooo', $_SERVER['__event.test1']);
         $this->assertSame('baar', $_SERVER['__event.test2']);
     }
+
+    public function testShouldBroadcastSuccess()
+    {
+        $d = m::mock(Dispatcher::class);
+
+        $d->makePartial()->shouldAllowMockingProtectedMethods();
+
+        $event = new BroadcastEvent();
+
+        $this->assertTrue($d->shouldBroadcast([$event]));
+    }
+
+    public function testShouldBroadcastFail()
+    {
+        $d = m::mock(Dispatcher::class);
+
+        $d->makePartial()->shouldAllowMockingProtectedMethods();
+
+        $event = new BroadcastFalseCondition();
+
+        $this->assertFalse($d->shouldBroadcast([$event]));
+    }
 }
 
 class TestDispatcherQueuedHandler implements \Illuminate\Contracts\Queue\ShouldQueue
@@ -274,3 +297,24 @@ class AnotherEvent implements SomeEventInterface
 {
     //
 }
+
+class BroadcastEvent implements ShouldBroadcast
+{
+    public function broadcastOn()
+    {
+        return ['test-channel'];
+    }
+
+    public function broadcastWhen()
+    {
+        return true;
+    }
+}
+
+class BroadcastFalseCondition extends BroadcastEvent
+{
+    public function broadcastWhen()
+    {
+        return false;
+    }
+}