fix laravel/framework#22804 + adding some unit test

Mailable.php

@@ -118,6 +118,13 @@ class Mailable implements MailableContract, Renderable
      */
     public $rawAttachments = [];
 
+	/**
+	 * The attachments coming from storage disk
+	 *
+	 * @var array
+	 */
+    public $diskAttachments = [];
+
     /**
      * The callbacks for the message.
      *
@@ -345,6 +352,15 @@ protected function buildAttachments($message)
             );
         }
 
+        foreach ($this->diskAttachments as $attachment) {
+	        $storage = Container::getInstance()->make(FilesystemFactory::class)->disk($attachment['disk']);
+
+	        return $message->attachData(
+		        $storage->get($attachment['path']), $attachment['name'] ?? basename($attachment['path']),
+		        array_merge(['mime' => $storage->mimeType($attachment['path'])], $attachment['options'])
+	        );
+        }
+
         return $this;
     }
 
@@ -725,12 +741,10 @@ public function attachFromStorage($path, $name = null, array $options = [])
      */
     public function attachFromStorageDisk($disk, $path, $name = null, array $options = [])
     {
-        $storage = Container::getInstance()->make(FilesystemFactory::class)->disk($disk);
+    	$name = $name ?? basename($path);
+	    $this->diskAttachments[] = compact('disk', 'path', 'name', 'options');
 
-        return $this->attachData(
-            $storage->get($path), $name ?? basename($path),
-            array_merge(['mime' => $storage->mimeType($path)], $options)
-        );
+        return $this;
     }
 
     /**