feat: add drawing pass-through support for unsupported elements

Author: rpg600

src/PhpSpreadsheet/Reader/BaseReader.php

@@ -60,6 +60,14 @@ abstract class BaseReader implements IReader
      */
     protected bool $createBlankSheetIfNoneRead = false;
 
+    /**
+     * Enable drawing pass-through?
+     * Identifies whether the Reader should preserve unsupported drawing elements (shapes, grouped images, etc.)
+     * by storing the original XML for pass-through during write operations.
+     * When enabled, drawings cannot be modified programmatically but are preserved exactly.
+     */
+    protected bool $enableDrawingPassThrough = false;
+
     /**
      * IReadFilter instance.
      */
@@ -125,6 +133,18 @@ public function setIncludeCharts(bool $includeCharts): self
         return $this;
     }
 
+    public function getEnableDrawingPassThrough(): bool
+    {
+        return $this->enableDrawingPassThrough;
+    }
+
+    public function setEnableDrawingPassThrough(bool $enableDrawingPassThrough): self
+    {
+        $this->enableDrawingPassThrough = $enableDrawingPassThrough;
+
+        return $this;
+    }
+
     /** @return null|string[] */
     public function getLoadSheetsOnly(): ?array
     {

src/PhpSpreadsheet/Reader/Xlsx.php

@@ -1481,6 +1481,11 @@ protected function loadSpreadsheetFromFile(string $filename): Spreadsheet
                                         $xmlDrawing = $this->loadZipNoNamespace($fileDrawing, '');
                                         $xmlDrawingChildren = $xmlDrawing->children(Namespaces::SPREADSHEET_DRAWING);
 
+                                        // Store drawing XML for pass-through if enabled
+                                        if ($this->enableDrawingPassThrough) {
+                                            $unparsedDrawings[$drawingRelId] = $xmlDrawing->asXML();
+                                        }
+
                                         if ($xmlDrawingChildren->oneCellAnchor) {
                                             foreach ($xmlDrawingChildren->oneCellAnchor as $oneCellAnchor) {
                                                 $oneCellAnchor = self::testSimpleXml($oneCellAnchor);

src/PhpSpreadsheet/Writer/Xlsx/Drawing.php

@@ -23,6 +23,12 @@ class Drawing extends WriterPart
      */
     public function writeDrawings(\PhpOffice\PhpSpreadsheet\Worksheet\Worksheet $worksheet, bool $includeCharts = false): string
     {
+        // Check if we have stored drawing XML (pass-through for unsupported elements)
+        $unparsedLoadedData = $worksheet->getParentOrThrow()->getUnparsedLoadedData();
+        if (isset($unparsedLoadedData['sheets'][$worksheet->getCodeName()]['Drawings'])) {
+            return reset($unparsedLoadedData['sheets'][$worksheet->getCodeName()]['Drawings']);
+        }
+
         // Create XML writer
         $objWriter = null;
         if ($this->getParentWriter()->getUseDiskCaching()) {