Fix #853 when loading and saving XLSX file with empty drawing cause c… (#882)

* Fix #853 when loading and saving XLSX file with empty drawing cause corrupted output file. Store empty drawing as unparsed entity and save it as is when saving the file.

* Fix code style

src/PhpSpreadsheet/Reader/Xlsx.php

@@ -1598,8 +1598,10 @@ class Xlsx extends BaseReader
                                     }
                                 }
                                 if ($xmlSheet->drawing && !$this->readDataOnly) {
+                                    $unparsedDrawings = [];
                                     foreach ($xmlSheet->drawing as $drawing) {
-                                        $fileDrawing = $drawings[(string) self::getArrayItem($drawing->attributes('http://schemas.openxmlformats.org/officeDocument/2006/relationships'), 'id')];
+                                        $drawingRelId = (string) self::getArrayItem($drawing->attributes('http://schemas.openxmlformats.org/officeDocument/2006/relationships'), 'id');
+                                        $fileDrawing = $drawings[$drawingRelId];
                                         //~ http://schemas.openxmlformats.org/package/2006/relationships"
                                         $relsDrawing = simplexml_load_string(
                                             $this->securityScanner->scan(
@@ -1631,10 +1633,11 @@ class Xlsx extends BaseReader
                                             $this->securityScanner->scan($this->getFromZipArchive($zip, $fileDrawing)),
                                             'SimpleXMLElement',
                                             Settings::getLibXmlLoaderOptions()
-                                        )->children('http://schemas.openxmlformats.org/drawingml/2006/spreadsheetDrawing');
+                                        );
+                                        $xmlDrawingChildren = $xmlDrawing->children('http://schemas.openxmlformats.org/drawingml/2006/spreadsheetDrawing');
 
-                                        if ($xmlDrawing->oneCellAnchor) {
+                                        if ($xmlDrawingChildren->oneCellAnchor) {
-                                            foreach ($xmlDrawing->oneCellAnchor as $oneCellAnchor) {
+                                            foreach ($xmlDrawingChildren->oneCellAnchor as $oneCellAnchor) {
                                                 if ($oneCellAnchor->pic->blipFill) {
                                                     /** @var SimpleXMLElement $blip */
                                                     $blip = $oneCellAnchor->pic->blipFill->children('http://schemas.openxmlformats.org/drawingml/2006/main')->blip;
@@ -1690,8 +1693,8 @@ class Xlsx extends BaseReader
                                                 }
                                             }
                                         }
-                                        if ($xmlDrawing->twoCellAnchor) {
+                                        if ($xmlDrawingChildren->twoCellAnchor) {
-                                            foreach ($xmlDrawing->twoCellAnchor as $twoCellAnchor) {
+                                            foreach ($xmlDrawingChildren->twoCellAnchor as $twoCellAnchor) {
                                                 if ($twoCellAnchor->pic->blipFill) {
                                                     $blip = $twoCellAnchor->pic->blipFill->children('http://schemas.openxmlformats.org/drawingml/2006/main')->blip;
                                                     $xfrm = $twoCellAnchor->pic->spPr->children('http://schemas.openxmlformats.org/drawingml/2006/main')->xfrm;
@@ -1757,13 +1760,21 @@ class Xlsx extends BaseReader
                                                 }
                                             }
                                         }
+                                        if ($relsDrawing === false && $xmlDrawing->count() == 0) {
+                                            // Save Drawing without rels and children as unparsed
+                                            $unparsedDrawings[$drawingRelId] = $xmlDrawing->asXML();
+                                        }
                                     }
 
                                     // store original rId of drawing files
                                     $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['drawingOriginalIds'] = [];
                                     foreach ($relsWorksheet->Relationship as $ele) {
                                         if ($ele['Type'] == 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/drawing') {
-                                            $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['drawingOriginalIds'][(string) $ele['Target']] = (string) $ele['Id'];
+                                            $drawingRelId = (string) $ele['Id'];
+                                            $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['drawingOriginalIds'][(string) $ele['Target']] = $drawingRelId;
+                                            if (isset($unparsedDrawings[$drawingRelId])) {
+                                                $unparsedLoadedData['sheets'][$docSheet->getCodeName()]['Drawings'][$drawingRelId] = $unparsedDrawings[$drawingRelId];
+                                            }
                                         }
                                     }
 

src/PhpSpreadsheet/Writer/Xlsx.php

@@ -328,6 +328,17 @@ class Xlsx extends BaseWriter
                     $zip->addFromString('xl/drawings/drawing' . ($i + 1) . '.xml', $this->getWriterPart('Drawing')->writeDrawings($this->spreadSheet->getSheet($i), $this->includeCharts));
                 }
 
+                // Add unparsed drawings
+                if (isset($unparsedLoadedData['sheets'][$sheetCodeName]['Drawings'])) {
+                    foreach ($unparsedLoadedData['sheets'][$sheetCodeName]['Drawings'] as $relId => $drawingXml) {
+                        $drawingFile = array_search($relId, $unparsedLoadedData['sheets'][$sheetCodeName]['drawingOriginalIds']);
+                        if ($drawingFile !== false) {
+                            $drawingFile = ltrim($drawingFile, '.');
+                            $zip->addFromString('xl' . $drawingFile, $drawingXml);
+                        }
+                    }
+                }
+
                 // Add comment relationship parts
                 if (count($this->spreadSheet->getSheet($i)->getComments()) > 0) {
                     // VML Comments
@@ -338,8 +349,8 @@ class Xlsx extends BaseWriter
                 }
 
                 // Add unparsed relationship parts
-                if (isset($unparsedLoadedData['sheets'][$this->spreadSheet->getSheet($i)->getCodeName()]['vmlDrawings'])) {
+                if (isset($unparsedLoadedData['sheets'][$sheetCodeName]['vmlDrawings'])) {
-                    foreach ($unparsedLoadedData['sheets'][$this->spreadSheet->getSheet($i)->getCodeName()]['vmlDrawings'] as $vmlDrawing) {
+                    foreach ($unparsedLoadedData['sheets'][$sheetCodeName]['vmlDrawings'] as $vmlDrawing) {
                         $zip->addFromString($vmlDrawing['filePath'], $vmlDrawing['content']);
                     }
                 }

tests/PhpSpreadsheetTests/Reader/XlsxTest.php

@@ -3,6 +3,7 @@
 namespace PhpOffice\PhpSpreadsheetTests\Reader;
 
 use PhpOffice\PhpSpreadsheet\Reader\Xlsx;
+use PhpOffice\PhpSpreadsheet\Shared\File;
 use PHPUnit\Framework\TestCase;
 
 class XlsxTest extends TestCase
@@ -32,4 +33,21 @@ class XlsxTest extends TestCase
             $this->assertEquals($ref, \array_slice($data[$i], 0, 10, true));
         }
     }
+
+    /**
+     * Test correct save and load xlsx files with empty drawings.
+     * Such files can be generated by Google Sheets.
+     */
+    public function testLoadSaveWithEmptyDrawings()
+    {
+        $filename = __DIR__ . '/../../data/Reader/XLSX/empty_drawing.xlsx';
+        $reader = new Xlsx();
+        $excel = $reader->load($filename);
+        $resultFilename = tempnam(File::sysGetTempDir(), 'phpspreadsheet-test');
+        $writer = new \PhpOffice\PhpSpreadsheet\Writer\Xlsx($excel);
+        $writer->save($resultFilename);
+        $excel = $reader->load($resultFilename);
+        // Fake assert. The only thing we need is to ensure the file is loaded without exception
+        $this->assertNotNull($excel);
+    }
 }