General Style Specified in Uppercase in Input Xlsx

Fix PHPOffice#2450. Treat input style GENERAL as if it were expected upper/lowercase.

src/PhpSpreadsheet/Reader/Xlsx/Styles.php

@@ -94,7 +94,7 @@ private function readNumberFormat(NumberFormat $numfmtStyle, SimpleXMLElement $n
         }
         $numfmt = Xlsx::getAttributes($numfmtStyleXml);
         if ($numfmt->count() > 0 && isset($numfmt['formatCode'])) {
-            $numfmtStyle->setFormatCode((string) $numfmt['formatCode']);
+            $numfmtStyle->setFormatCode(self::formatGeneral((string) $numfmt['formatCode']));
         }
     }
 
@@ -183,6 +183,15 @@ public function readAlignmentStyle(Alignment $alignment, SimpleXMLElement $align
         );
     }
 
+    private function formatGeneral(string $formatString): string
+    {
+        if ($formatString === 'GENERAL') {
+            $formatString = NumberFormat::FORMAT_GENERAL;
+        }
+
+        return $formatString;
+    }
+
     /**
      * Read style.
      *
@@ -193,7 +202,7 @@ public function readStyle(Style $docStyle, $style): void
         if ($style->numFmt instanceof SimpleXMLElement) {
             $this->readNumberFormat($docStyle->getNumberFormat(), $style->numFmt);
         } else {
-            $docStyle->getNumberFormat()->setFormatCode($style->numFmt);
+            $docStyle->getNumberFormat()->setFormatCode(self::formatGeneral((string) $style->numFmt));
         }
 
         if (isset($style->font)) {

tests/PhpSpreadsheetTests/Reader/Xlsx/Issue2450Test.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheetTests\Reader\Xlsx;
+
+use PhpOffice\PhpSpreadsheet\IOFactory;
+use PHPUnit\Framework\TestCase;
+
+class Issue2450Test extends TestCase
+{
+    public function testIssue2450(): void
+    {
+        // Style specified as GENERAL rather than General.
+        $filename = 'tests/data/Reader/XLSX/issue.2450.xlsx';
+        $reader = IOFactory::createReader('Xlsx');
+        $spreadsheet = $reader->load($filename);
+        $sheet = $spreadsheet->getActiveSheet();
+        $sheet = $spreadsheet->getActiveSheet();
+        $birthYears = [
+            'C2' => $sheet->getCell('C2')->getFormattedValue(),
+            'C3' => $sheet->getCell('C3')->getFormattedValue(),
+            'C4' => $sheet->getCell('C4')->getFormattedValue(),
+        ];
+        self::assertSame(
+            [
+                'C2' => '1932',
+                'C3' => '1964',
+                'C4' => '1988',
+            ],
+            $birthYears
+        );
+
+        $spreadsheet->disconnectWorksheets();
+    }
+}