Fix infinite loop in recursive generics (#5288)

Author: staabm

src/Type/Generic/GenericObjectType.php

@@ -19,6 +19,7 @@
 use PHPStan\Type\IntersectionType;
 use PHPStan\Type\IsSuperTypeOfResult;
 use PHPStan\Type\ObjectType;
+use PHPStan\Type\RecursionGuard;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeWithClassName;
 use PHPStan\Type\UnionType;
@@ -95,7 +96,11 @@ public function getReferencedClasses(): array
 	{
 		$classes = parent::getReferencedClasses();
 		foreach ($this->types as $type) {
-			foreach ($type->getReferencedClasses() as $referencedClass) {
+			$referencedClasses = RecursionGuard::runOnObjectIdentity($type, static fn () => $type->getReferencedClasses());
+			if ($referencedClasses instanceof ErrorType) {
+				continue;
+			}
+			foreach ($referencedClasses as $referencedClass) {
 				$classes[] = $referencedClass;
 			}
 		}

tests/PHPStan/Analyser/AnalyserIntegrationTest.php

@@ -1499,6 +1499,13 @@ public function testBug14324(): void
 		$this->assertNoErrors($errors);
 	}
 
+	public function testBug13801(): void
+	{
+		// endless loop crash
+		$errors = $this->runAnalyse(__DIR__ . '/data/bug-13801.php');
+		$this->assertNoErrors($errors);
+	}
+
 	/**
 	 * @param string[]|null $allAnalysedFiles
 	 * @return list<Error>

tests/PHPStan/Analyser/data/bug-13801.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bug13801;
+
+/**
+ * @template TValue of object
+ */
+interface Cast
+{
+}
+
+/**
+ * @template TCast of Cast<static>
+ */
+interface Castable
+{
+}