<NME> NullableReturnTypeHintedClass.php
<BEF> <?php

namespace ZendTest\Code\TestAsset;

class NullableReturnTypeHintedClass
{
    public function arrayReturn() : ?array
    {
    }

    public function callableReturn() : ?callable
    {
    }

    public function intReturn() : ?int
    {
    }

    public function floatReturn() : ?float
    {
    }

    public function stringReturn() : ?string
    {
    }

    public function boolReturn() : ?bool
    {
    }

    public function selfReturn() : ?self
    {
    }

    public function classReturn() : ?NullableReturnTypeHintedClass
    {
    }

    public function otherClassReturn() : ?InternalHintsClass
    {
    }
}

<MSG> Adding `parent` nullable return type hint

<DFF> @@ -2,7 +2,7 @@
 
 namespace ZendTest\Code\TestAsset;
 
-class NullableReturnTypeHintedClass
+class NullableReturnTypeHintedClass extends EmptyClass
 {
     public function arrayReturn() : ?array
     {
@@ -32,6 +32,10 @@ class NullableReturnTypeHintedClass
     {
     }
 
+    public function parentReturn() : ?parent
+    {
+    }
+
     public function classReturn() : ?NullableReturnTypeHintedClass
     {
     }

Adding `parent` nullable return type hint