Add non regression test

Author: VincentLanglet

tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php

@@ -1149,6 +1149,12 @@ public function testBug6209(): void
 		$this->analyse([__DIR__ . '/data/bug-6209.php'], []);
 	}
 
+	public function testBug11602(): void
+	{
+		$this->reportPossiblyNonexistentConstantArrayOffset = true;
+		$this->analyse([__DIR__ . '/data/bug-11602.php'], []);
+	}
+
 	public function testBug11276(): void
 	{
 		$this->reportPossiblyNonexistentConstantArrayOffset = true;

tests/PHPStan/Rules/Arrays/data/bug-11602.php

@@ -0,0 +1,23 @@
+<?php declare(strict_types = 1);
+
+namespace Bug11602;
+
+class HelloWorld
+{
+	public function parseRef(string $coordinate, string $ref): string
+	{
+		if (preg_match('/^([A-Z]{1,3})([0-9]{1,7})(:([A-Z]{1,3})([0-9]{1,7}))?$/', $ref, $matches) !== 1) {
+			return $ref;
+		}
+		if (!isset($matches[5])) { // single cell, not range
+			return $coordinate;
+		}
+		$minRow = (int) $matches[2];
+		$maxRow = (int) $matches[5];
+		$rows = $maxRow - $minRow + 1;
+		$minCol = $matches[1];
+		$maxCol = $matches[4];
+
+		return "$minCol$minRow:$maxCol$maxRow";
+	}
+}