Offer Tcpdf Interface Which Throws Exception Rather than Die

src/PhpSpreadsheet/Writer/Pdf/Tcpdf.php

@@ -30,9 +30,15 @@ public function __construct(Spreadsheet $spreadsheet)
      */
     protected function createExternalWriterInstance(string $orientation, string $unit, $paperSize): \TCPDF
     {
+        $this->defines();
+
         return new \TCPDF($orientation, $unit, $paperSize);
     }
 
+    protected function defines(): void
+    {
+    }
+
     /**
      * Save Spreadsheet to file.
      *

src/PhpSpreadsheet/Writer/Pdf/TcpdfNoDie.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Writer\Pdf;
+
+class TcpdfNoDie extends Tcpdf
+{
+    /**
+     * By default, Tcpdf will die sometimes rather than throwing exception.
+     * And this is controlled by a defined constant in the global namespace,
+     * not by an instance property. Ugh!
+     * Using this class instead of the class which it extends will probably
+     * be suitable for most users. But not for those who have customized
+     * their config file. Which is why this isn't the default, so that
+     * there is no breaking change for those users.
+     * Note that if both Tcpdf and TcpdfNoDie are used in the same process,
+     * the first one used "wins" the battle of the defines.
+     */
+    protected function defines(): void
+    {
+        if (!defined('K_TCPDF_EXTERNAL_CONFIG')) {
+            define('K_TCPDF_EXTERNAL_CONFIG', true);
+        }
+        if (!defined('K_TCPDF_THROW_EXCEPTION_ERROR')) {
+            define('K_TCPDF_THROW_EXCEPTION_ERROR', true);
+        }
+    }
+}

tests/PhpSpreadsheetTests/Writer/Tcpdf/NoDieTest.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheetTests\Writer\Tcpdf;
+
+use Exception;
+use PhpOffice\PhpSpreadsheet\Spreadsheet;
+use PhpOffice\PhpSpreadsheet\Writer\Pdf\TcpdfNoDie;
+use PHPUnit\Framework\Attributes;
+
+class NoDieTest extends \PHPUnit\Framework\TestCase
+{
+    private Spreadsheet $spreadsheet;
+
+    protected function setUp(): void
+    {
+        $this->spreadsheet = new Spreadsheet();
+    }
+
+    protected function tearDown(): void
+    {
+        unset($this->spreadsheet);
+    }
+
+    // Separate processes because of global defined names
+    #[Attributes\RunInSeparateProcess]
+    #[Attributes\PreserveGlobalState(false)]
+    public function testExceptionRatherThanDie(): void
+    {
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage('Could not include font definition file');
+        $sheet = $this->spreadsheet->getActiveSheet();
+        $sheet->setCellValue('A1', 'cell');
+        $writer = new TcpdfNoDie($this->spreadsheet);
+        $writer->setFont('xyz');
+        $writer->save('php://memory');
+    }
+}