From 6497c6c455ef0cb2debe1891d6c6d00ece95a3c2 Mon Sep 17 00:00:00 2001
From: Ilija Tovilo <ilija.tovilo@me.com>
Date: Wed, 20 Aug 2025 23:20:47 +0200
Subject: [PATCH] Don't substitute self/parent with anonymous class

Fixes GH-18373
Closes GH-19537
---
 NEWS                              |  2 ++
 Zend/tests/gh19304.phpt           |  2 +-
 Zend/zend_compile.c               |  8 ++++++--
 ext/reflection/tests/gh18373.phpt | 14 ++++++++++++++
 4 files changed, 23 insertions(+), 3 deletions(-)
 create mode 100644 ext/reflection/tests/gh18373.phpt

diff --git a/NEWS b/NEWS
index 6c2db856000..3bcc968bab6 100644
--- a/NEWS
+++ b/NEWS
@@ -25,6 +25,8 @@ PHP                                                                        NEWS
     operators" RFC, meaning that incrementing non-numeric strings is now
     deprecated. (Girgias).
   . Various closure binding issues are now deprecated. (alexandre-daubois)
+  . Fixed bug GH-18373 (Don't substitute self/parent with anonymous class).
+    (ilutov)
 
 - Filter:
   . Added support for configuring the URI parser for FILTER_VALIDATE_URL
diff --git a/Zend/tests/gh19304.phpt b/Zend/tests/gh19304.phpt
index c77fc2d6fac..47e20af6462 100644
--- a/Zend/tests/gh19304.phpt
+++ b/Zend/tests/gh19304.phpt
@@ -15,4 +15,4 @@ try {
 
 ?>
 --EXPECT--
-Cannot assign int to property class@anonymous::$v of type class@anonymous
+Cannot assign int to property class@anonymous::$v of type self
diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 205023fa69b..503b4699742 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -7091,16 +7091,20 @@ static zend_type zend_compile_single_typename(zend_ast *ast)
 				ZEND_ASSERT(fetch_type == ZEND_FETCH_CLASS_SELF || fetch_type == ZEND_FETCH_CLASS_PARENT);
 
 				zend_ensure_valid_class_fetch_type(fetch_type);
+
+				bool substitute_self_parent = zend_is_scope_known()
+					&& !(CG(active_class_entry)->ce_flags & ZEND_ACC_ANON_CLASS);
+
 				if (fetch_type == ZEND_FETCH_CLASS_SELF) {
 					/* Scope might be unknown for unbound closures and traits */
-					if (zend_is_scope_known()) {
+					if (substitute_self_parent) {
 						class_name = CG(active_class_entry)->name;
 						ZEND_ASSERT(class_name && "must know class name when resolving self type at compile time");
 					}
 				} else {
 					ZEND_ASSERT(fetch_type == ZEND_FETCH_CLASS_PARENT);
 					/* Scope might be unknown for unbound closures and traits */
-					if (zend_is_scope_known()) {
+					if (substitute_self_parent) {
 						class_name = CG(active_class_entry)->parent_name;
 						ZEND_ASSERT(class_name && "must know class name when resolving parent type at compile time");
 					}
diff --git a/ext/reflection/tests/gh18373.phpt b/ext/reflection/tests/gh18373.phpt
new file mode 100644
index 00000000000..30aa1a0f5fe
--- /dev/null
+++ b/ext/reflection/tests/gh18373.phpt
@@ -0,0 +1,14 @@
+--TEST--
+GH-18373: Don't substitute self/parent with anonymous class
+--FILE--
+<?php
+
+$o = new class() {
+    public function test(): self {}
+};
+
+echo (new ReflectionClass($o))->getMethod('test')->getReturnType()->getName(), "\n";
+
+?>
+--EXPECT--
+self