pFilename is required parameter for save

Author: Sergei Lomakov

Classes/PHPPowerPoint/Writer/ODPresentation.php

@@ -102,8 +102,11 @@ public function __construct(PHPPowerPoint $pPHPPowerPoint = null)
      * @param  string    $pFilename
      * @throws Exception
      */
-    public function save($pFilename = null)
+    public function save($pFilename)
     {
+        if (empty($pFilename)) {
+            throw new Exception("Filename is empty");
+        }
         if (!is_null($this->_presentation)) {
             // If $pFilename is php://output or php://stdout, make it a temporary file...
             $originalFilename = $pFilename;

Classes/PHPPowerPoint/Writer/PowerPoint2007.php

@@ -139,8 +139,11 @@ public function getWriterPart($pPartName = '')
      * @param  string    $pFilename
      * @throws Exception
      */
-    public function save($pFilename = null)
+    public function save($pFilename)
     {
+        if (empty($pFilename)) {
+            throw new Exception("Filename is empty");
+        }
         if (!is_null($this->_presentation)) {
             // If $pFilename is php://output or php://stdout, make it a temporary file...
             $originalFilename = $pFilename;

Classes/PHPPowerPoint/Writer/Serialized.php

@@ -58,8 +58,11 @@ public function __construct(PHPPowerPoint $pPHPPowerPoint = null)
      * @param  string    $pFilename
      * @throws Exception
      */
-    public function save($pFilename = null)
+    public function save($pFilename)
     {
+        if (empty($pFilename)) {
+            throw new Exception("Filename is empty");
+        }
         if (!is_null($this->_presentation)) {
             // Create new ZIP file and open it for writing
             $objZip = new ZipArchive();