add more tests and fix a small visibility issue

Author: withinboredom

Zend/zend_API.c

@@ -1816,17 +1816,19 @@ static zend_always_inline zend_result _object_and_properties_init(zval *arg, zen
 		return FAILURE;
 	}
 
-	if (class_type->required_scope) {
-		const zend_class_entry *scope = zend_get_executed_scope();
+	const zend_class_entry *check_class = class_type;
+	const zend_class_entry *scope = zend_get_executed_scope();
+check_lexical_scope:
+	if (check_class->required_scope) {
 		if (UNEXPECTED(scope == NULL)) {
 			zend_type_error("Cannot instantiate class %s from the global scope", ZSTR_VAL(class_type->name));
 			ZVAL_NULL(arg);
 			Z_OBJ_P(arg) = NULL;
 			return FAILURE;
 		}
 
-		if (class_type->required_scope_absolute) {
-			if (scope != class_type->required_scope && scope->lexical_scope != class_type->required_scope) {
+		if (check_class->required_scope_absolute) {
+			if (scope != check_class->required_scope && scope->lexical_scope != check_class->required_scope) {
 				zend_type_error("Cannot instantiate private class %s from scope %s", ZSTR_VAL(class_type->name), ZSTR_VAL(scope->name));
 				ZVAL_NULL(arg);
 				Z_OBJ_P(arg) = NULL;
@@ -1837,6 +1839,11 @@ static zend_always_inline zend_result _object_and_properties_init(zval *arg, zen
 		}
 	}
 
+	if (check_class != scope && check_class->lexical_scope && check_class->lexical_scope->type != ZEND_NAMESPACE_CLASS) {
+		check_class = check_class->lexical_scope;
+		goto check_lexical_scope;
+	}
+
 	if (UNEXPECTED(!(class_type->ce_flags & ZEND_ACC_CONSTANTS_UPDATED))) {
 		if (UNEXPECTED(zend_update_class_constants(class_type) != SUCCESS)) {
 			ZVAL_NULL(arg);

tests/classes/inner_classes/visibility_011.phpt

@@ -0,0 +1,34 @@
+--TEST--
+returning private class via interface
+--FILE--
+<?php
+interface test {
+    static function foo(): self;
+}
+
+class Outer {
+  private class Middle {
+    public class Inner implements test {
+      public static function foo(): self {
+        return new self();
+      }
+    }
+  }
+  private function foo(Middle\Inner $inner) {} // we can see Middle\Inner here
+  public function test(): test {
+    $this->foo($return = Middle\Inner::foo());
+    return $return;
+  }
+}
+
+var_dump(new Outer()->test());
+var_dump(new Outer\Middle\Inner());
+?>
+--EXPECTF--
+object(Outer\Middle\Inner)#2 (0) {
+}
+
+Fatal error: Uncaught TypeError: Cannot instantiate class Outer\Middle\Inner from the global scope in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d

tests/classes/inner_classes/visibility_012.phpt

@@ -0,0 +1,21 @@
+--TEST--
+instantiate nested private classes
+--FILE--
+<?php
+class Outer {
+    private class Middle {
+        public class Inner {}
+    }
+
+    private Middle\Inner $inner;
+
+    public function __construct() {
+        $this->inner = new Middle\Inner();
+    }
+}
+
+$x = new Outer();
+echo "success\n";
+?>
+--EXPECT--
+success