[12.x] Add ability to default the mailable and notifcation queue

src/Illuminate/Mail/Mailable.php

@@ -189,6 +189,13 @@ class Mailable implements MailableContract, Renderable
      */
     public static $viewDataCallback;
 
+    /**
+     * The name of the default queue that should be used when queued.
+     *
+     * @var string|null
+     */
+    public static $defaultQueue;
+
     /**
      * Send the message using the given mailer.
      *
@@ -230,7 +237,7 @@ public function queue(Queue $queue)
 
         $connection = property_exists($this, 'connection') ? $this->connection : null;
 
-        $queueName = property_exists($this, 'queue') ? $this->queue : null;
+        $queueName = (property_exists($this, 'queue') ? $this->queue : null) ?? static::$defaultQueue;
 
         return $queue->connection($connection)->pushOn(
             $queueName ?: null, $this->newQueuedJob()
@@ -248,7 +255,7 @@ public function later($delay, Queue $queue)
     {
         $connection = property_exists($this, 'connection') ? $this->connection : null;
 
-        $queueName = property_exists($this, 'queue') ? $this->queue : null;
+        $queueName = (property_exists($this, 'queue') ? $this->queue : null) ?? static::$defaultQueue;
 
         return $queue->connection($connection)->laterOn(
             $queueName ?: null, $delay, $this->newQueuedJob()

src/Illuminate/Notifications/Notification.php

@@ -22,6 +22,13 @@ class Notification
      */
     public $locale;
 
+    /**
+     * The name of the default queue that should be used when queued.
+     *
+     * @var string|null
+     */
+    public static $defaultQueue;
+
     /**
      * Get the channels the event should broadcast on.
      *

src/Illuminate/Notifications/NotificationSender.php

@@ -235,7 +235,7 @@ protected function queueNotification($notifiables, $notification)
                     $connection = $notification->viaConnections()[$channel] ?? null;
                 }
 
-                $queue = $notification->queue;
+                $queue = $notification->queue ?? Notification::$defaultQueue;
 
                 if (method_exists($notification, 'viaQueues')) {
                     $queue = $notification->viaQueues()[$channel] ?? null;

tests/Mail/MailableQueuedTest.php

@@ -15,6 +15,7 @@
 use Illuminate\Support\Testing\Fakes\QueueFake;
 use Laravel\SerializableClosure\SerializableClosure;
 use Mockery as m;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Mailer\Transport\TransportInterface;
 
@@ -25,18 +26,35 @@ protected function tearDown(): void
         m::close();
     }
 
-    public function testQueuedMailableSent(): void
+    public static function defaultQueueDataProvider()
     {
-        $queueFake = new QueueFake(new Application);
-        $mailer = $this->getMockBuilder(Mailer::class)
-            ->setConstructorArgs($this->getMocks())
-            ->onlyMethods(['createMessage', 'to'])
-            ->getMock();
-        $mailer->setQueue($queueFake);
-        $mailable = new MailableQueueableStub;
-        $queueFake->assertNothingPushed();
-        $mailer->send($mailable);
-        $queueFake->assertPushedOn(null, SendQueuedMailable::class);
+        return [
+            ['some-queue'],
+            [null],
+        ];
+    }
+
+    #[DataProvider('defaultQueueDataProvider')]
+    public function testDefaultQueue($queue): void
+    {
+        try {
+            if ($queue) {
+                Mailable::$defaultQueue = $queue;
+            }
+
+            $queueFake = new QueueFake(new Application);
+            $mailer = $this->getMockBuilder(Mailer::class)
+                ->setConstructorArgs($this->getMocks())
+                ->onlyMethods(['createMessage', 'to'])
+                ->getMock();
+            $mailer->setQueue($queueFake);
+            $mailable = new MailableQueueableStub;
+            $queueFake->assertNothingPushed();
+            $mailer->send($mailable);
+            $queueFake->assertPushedOn($queue, SendQueuedMailable::class);
+        } finally {
+            Mailable::$defaultQueue = null;
+        }
     }
 
     public function testQueuedMailableWithAttachmentSent(): void

tests/Notifications/NotificationSenderTest.php

@@ -14,6 +14,7 @@
 use Illuminate\Notifications\Notification;
 use Illuminate\Notifications\NotificationSender;
 use Mockery as m;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Mailer\Exception\HttpTransportException;
 use Symfony\Component\Mailer\Exception\TransportException;
@@ -166,6 +167,51 @@ public function testNotificationFailedSentWithoutHttpTransportException()
 
         $sender->sendNow($notifiable, new DummyNotificationWithViaConnections(), ['mail']);
     }
+
+    public static function defaultNotificationQueueDataProvider()
+    {
+        return [
+            ['some-queue'],
+            [null],
+        ];
+    }
+
+    #[DataProvider('defaultNotificationQueueDataProvider')]
+    public function testDefaultNotificationQueue($queue)
+    {
+        try {
+            if ($queue) {
+                Notification::$defaultQueue = $queue;
+            }
+
+            $notifiable = new NotifiableUser;
+            $manager = m::mock(ChannelManager::class);
+            $manager->shouldReceive('getContainer')->andReturn(app());
+
+            $dispatchedJob = null;
+            $bus = m::mock(BusDispatcher::class);
+            $bus->shouldReceive('dispatch')
+                ->once()
+                ->withArgs(function ($job) use ($queue, &$dispatchedJob) {
+                    $dispatchedJob = $job;
+
+                    return $job->queue === $queue;
+                });
+
+            $events = m::mock(EventDispatcher::class);
+            $events->shouldReceive('listen')->once();
+
+            $sender = new NotificationSender($manager, $bus, $events);
+
+            $notification = new DummyNotificationWithMiddleware;
+
+            $sender->send($notifiable, $notification);
+
+            $this->assertSame($queue, $dispatchedJob->queue);
+        } finally {
+            Notification::$defaultQueue = null;
+        }
+    }
 }
 
 class DummyQueuedNotificationWithStringVia extends Notification implements ShouldQueue