gen_stub: Add return by reference flag

ext/zend_test/test.c

@@ -1045,6 +1045,28 @@ static ZEND_METHOD(_ZendTestClass, takesUnionType)
 	RETURN_NULL();
 }
 
+static ZEND_METHOD(_ZendTestClass, returnByRefIntProp)
+{
+	ZEND_PARSE_PARAMETERS_NONE();
+
+	zend_object *obj = Z_OBJ_P(ZEND_THIS);
+	zend_string *name = zend_string_init("intProp", strlen("intProp"), false);
+	zval *int_prop = obj->handlers->get_property_ptr_ptr(obj, name, BP_VAR_W, NULL);
+	zend_string_release_ex(name, false);
+
+	ZEND_ASSERT(int_prop);
+	ZEND_ASSERT(!Z_ISERROR_P(int_prop));
+
+	if (!Z_ISREF_P(int_prop)) {
+		zend_property_info *prop_info = zend_get_property_info_for_slot(obj, int_prop);
+		ZEND_ASSERT(ZEND_TYPE_IS_SET(prop_info->type));
+		ZVAL_MAKE_REF(int_prop);
+		ZEND_REF_ADD_TYPE_SOURCE(Z_REF_P(int_prop), prop_info);
+	}
+
+	ZVAL_COPY(return_value, int_prop);
+}
+
 // Returns a newly allocated DNF type `Iterator|(Traversable&Countable)`.
 //
 // We need to generate it "manually" because gen_stubs.php does not support codegen for DNF types ATM.

ext/zend_test/test.stub.php

@@ -65,6 +65,8 @@ public function returnsThrowable(): Throwable {}
         static public function variadicTest(string|Iterator ...$elements) : static {}
 
         public function takesUnionType(stdclass|Iterator $arg): void {}
+
+        public function &returnByRefIntProp(): int {}
     }
 
     class _ZendTestMagicCall

ext/zend_test/tests/gen_stub_test_return_by_ref.phpt

@@ -0,0 +1,51 @@
+--TEST--
+gen_stub.php: Test that return by ref flag is set
+--EXTENSIONS--
+zend_test
+--FILE--
+<?php
+
+$reflectionMethod = new ReflectionMethod(_ZendTestClass::class, "returnByRefIntProp");
+var_dump($reflectionMethod->returnsReference());
+
+$o = new _ZendTestClass();
+var_dump($o);
+$i =& $o->returnByRefIntProp();
+var_dump($i);
+$i = 24;
+var_dump($i);
+var_dump($o);
+
+?>
+--EXPECT--
+bool(true)
+object(_ZendTestClass)#2 (3) {
+  ["intProp"]=>
+  int(123)
+  ["classProp"]=>
+  NULL
+  ["classUnionProp"]=>
+  NULL
+  ["classIntersectionProp"]=>
+  uninitialized(Traversable&Countable)
+  ["readonlyProp"]=>
+  uninitialized(int)
+  ["dnfProperty"]=>
+  uninitialized(Iterator|(Traversable&Countable))
+}
+int(123)
+int(24)
+object(_ZendTestClass)#2 (3) {
+  ["intProp"]=>
+  &int(24)
+  ["classProp"]=>
+  NULL
+  ["classUnionProp"]=>
+  NULL
+  ["classIntersectionProp"]=>
+  uninitialized(Traversable&Countable)
+  ["readonlyProp"]=>
+  uninitialized(int)
+  ["dnfProperty"]=>
+  uninitialized(Iterator|(Traversable&Countable))
+}