Add regression test for invariant template type narrowed by control flow in a method getter (#5922)

Co-authored-by: staabm <120441+staabm@users.noreply.github.com>

Author: phpstan-bot

tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php

@@ -1353,4 +1353,10 @@ public function testBug12110(): void
 		$this->analyse([__DIR__ . '/data/bug-12110.php'], []);
 	}
 
+	#[RequiresPhp('>= 8.2.0')]
+	public function testBug11776(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-11776.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Methods/data/bug-11776.php

@@ -0,0 +1,29 @@
+<?php // lint >= 8.2
+
+declare(strict_types=1);
+
+namespace Bug11776;
+
+/**
+ * @template TOperation of int|string
+ */
+interface EnumAsFilterInterface {}
+
+/**
+ * @template TOperation of scalar
+ */
+final readonly class ScalarableChoice
+{
+	/**
+	 * @param class-string<EnumAsFilterInterface<(int|string)&TOperation>> $choiceClassName
+	 */
+	public function __construct(private string $choiceClassName) {}
+
+	/**
+	 * @return class-string<EnumAsFilterInterface<(int|string)&TOperation>>
+	 */
+	public function getChoiceClassName(): string
+	{
+		return $this->choiceClassName;
+	}
+}