Avoid getStyle on every setValueExplicit quote-prefix check

tests/Benchmark/LargeXlsxWriteBenchmarkTest.php

@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpOffice\PhpSpreadsheetBenchmarks;
+
+use PhpOffice\PhpSpreadsheet\Spreadsheet;
+use PhpOffice\PhpSpreadsheet\Writer\Xlsx;
+use PHPUnit\Framework\Attributes\Group;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Benchmark populate + Xlsx save for a large dense sheet.
+ *
+ * Run with: vendor/bin/phpunit --testsuite Benchmark --filter LargeXlsxWriteBenchmark --stderr
+ */
+#[Group('benchmark')]
+class LargeXlsxWriteBenchmarkTest extends TestCase
+{
+    private const ROWS = 2000;
+
+    private const COLS = 20;
+
+    public function testPopulateAndSaveLargeSheet(): void
+    {
+        $tmp = tempnam(sys_get_temp_dir(), 'phpspreadsheet-bench-');
+        self::assertNotFalse($tmp);
+        $filename = $tmp . '.xlsx';
+        @unlink($tmp);
+
+        $memBefore = memory_get_usage(true);
+        $start = hrtime(true);
+
+        $spreadsheet = new Spreadsheet();
+        $sheet = $spreadsheet->getActiveSheet();
+        for ($row = 1; $row <= self::ROWS; ++$row) {
+            for ($col = 1; $col <= self::COLS; ++$col) {
+                $sheet->getCell([$col, $row])->setValue("R{$row}C{$col}");
+            }
+        }
+
+        $writer = new Xlsx($spreadsheet);
+        $writer->setPreCalculateFormulas(false);
+        $writer->save($filename);
+
+        $elapsedMs = (hrtime(true) - $start) / 1e6;
+        $peakMiB = memory_get_peak_usage(true) / (1024 * 1024);
+        $deltaMiB = (memory_get_usage(true) - $memBefore) / (1024 * 1024);
+        $cellCount = self::ROWS * self::COLS;
+
+        fwrite(
+            STDERR,
+            sprintf(
+                "LargeXlsxWriteBenchmark: %d cells, %.1f ms, peak=%.1f MiB, delta=%.1f MiB, size=%.1f KiB\n",
+                $cellCount,
+                $elapsedMs,
+                $peakMiB,
+                $deltaMiB,
+                filesize($filename) / 1024
+            )
+        );
+
+        self::assertFileExists($filename);
+        self::assertGreaterThan(1000, filesize($filename));
+
+        $spreadsheet->disconnectWorksheets();
+        @unlink($filename);
+    }
+}