From 473fbb117d28e71639af14d2bb10af72362684e7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ji=C5=99=C3=AD=20Pudil?= <me@jiripudil.cz>
Date: Mon, 11 Nov 2024 13:54:39 +0100
Subject: [PATCH] ClassReflection: resolve missing template type to its default
 (if set) rather than bound

---
 src/Reflection/ClassReflection.php        |  2 +-
 src/Type/Generic/TemplateTypeHelper.php   | 11 ++++++++
 src/Type/GenericTypeVariableResolver.php  |  2 +-
 src/Type/ObjectType.php                   |  2 +-
 tests/PHPStan/Analyser/nsrt/bug-11899.php | 34 +++++++++++++++++++++++
 5 files changed, 48 insertions(+), 3 deletions(-)
 create mode 100644 tests/PHPStan/Analyser/nsrt/bug-11899.php

diff --git a/src/Reflection/ClassReflection.php b/src/Reflection/ClassReflection.php
index c79f2a6bed..ff45172fd8 100644
--- a/src/Reflection/ClassReflection.php
+++ b/src/Reflection/ClassReflection.php
@@ -1374,7 +1374,7 @@ public function getActiveTemplateTypeMap(): TemplateTypeMap
 				if ($type instanceof ErrorType) {
 					$templateType = $templateTypeMap->getType($name);
 					if ($templateType !== null) {
-						return TemplateTypeHelper::resolveToBounds($templateType);
+						return TemplateTypeHelper::resolveToDefaults($templateType);
 					}
 				}
 
diff --git a/src/Type/Generic/TemplateTypeHelper.php b/src/Type/Generic/TemplateTypeHelper.php
index 58460efaee..29ecd48720 100644
--- a/src/Type/Generic/TemplateTypeHelper.php
+++ b/src/Type/Generic/TemplateTypeHelper.php
@@ -68,6 +68,17 @@ public static function resolveTemplateTypes(
 		});
 	}
 
+	public static function resolveToDefaults(Type $type): Type
+	{
+		return TypeTraverser::map($type, static function (Type $type, callable $traverse): Type {
+			if ($type instanceof TemplateType) {
+				return $traverse($type->getDefault() ?? $type->getBound());
+			}
+
+			return $traverse($type);
+		});
+	}
+
 	public static function resolveToBounds(Type $type): Type
 	{
 		return TypeTraverser::map($type, static function (Type $type, callable $traverse): Type {
diff --git a/src/Type/GenericTypeVariableResolver.php b/src/Type/GenericTypeVariableResolver.php
index 8c3f7d2da5..eee42d0f1b 100644
--- a/src/Type/GenericTypeVariableResolver.php
+++ b/src/Type/GenericTypeVariableResolver.php
@@ -44,7 +44,7 @@ public static function getType(
 				return new MixedType(false);
 			}
 
-			return $bound;
+			return TemplateTypeHelper::resolveToDefaults($templateType);
 		}
 
 		return $type;
diff --git a/src/Type/ObjectType.php b/src/Type/ObjectType.php
index 3e8ac1371f..7427aa167c 100644
--- a/src/Type/ObjectType.php
+++ b/src/Type/ObjectType.php
@@ -841,7 +841,7 @@ public function getTemplateType(string $ancestorClassName, string $templateTypeN
 				return new MixedType(false);
 			}
 
-			return $bound;
+			return TemplateTypeHelper::resolveToDefaults($templateType);
 		}
 
 		return $type;
diff --git a/tests/PHPStan/Analyser/nsrt/bug-11899.php b/tests/PHPStan/Analyser/nsrt/bug-11899.php
new file mode 100644
index 0000000000..c56b47dfcb
--- /dev/null
+++ b/tests/PHPStan/Analyser/nsrt/bug-11899.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace Bug11899;
+
+use function PHPStan\Testing\assertType;
+
+abstract class Test {}
+
+interface InvertedQuestions {}
+
+class SomeTest extends Test implements InvertedQuestions {}
+
+/**
+ * @template TTestType = Test
+ * @property-read ?TTestType $test
+ */
+class UserTest {
+	public function __get() : mixed {
+		return new SomeTest();
+	}
+}
+
+function acceptUserTest1(UserTest $ut) : void {
+	assertType('Bug11899\\UserTest', $ut);
+	assertType('Bug11899\\Test|null', $ut->test);
+}
+
+/**
+ * @param UserTest<InvertedQuestions> $ut
+ */
+function acceptUserTest2(UserTest $ut) : void {
+	assertType('Bug11899\\UserTest<Bug11899\\InvertedQuestions>', $ut);
+	assertType('Bug11899\\InvertedQuestions|null', $ut->test);
+}