fix: Fix scoping of new statement with the new parent not being a name

specs/string-literal/new.php

@@ -180,4 +180,90 @@ class Ya_1
 
             PHP,
     ),
+
+    'new parent is a class name' => <<<'PHP'
+        <?php
+        namespace Acme;
+
+        class BplaaYai {}
+
+        new BplaaYai('abc');
+
+        ----
+        <?php
+
+        namespace Humbug\Acme;
+
+        class BplaaYai
+        {
+        }
+        new BplaaYai('abc');
+
+        PHP,
+
+    'new parent is a variable' => <<<'PHP'
+        <?php
+        namespace Acme;
+
+        class BplaaYai {}
+
+        $class = '\Acme\BplaaYai';
+        new $class('abc');
+
+        ----
+        <?php
+
+        namespace Humbug\Acme;
+
+        class BplaaYai
+        {
+        }
+        $class = 'Humbug\Acme\BplaaYai';
+        new $class('abc');
+
+        PHP,
+
+    'new parent is an expression (variable)' => <<<'PHP'
+        <?php
+        namespace Acme;
+
+        class BplaaYai {}
+
+        $class = '\Acme\BplaaYai';
+        new $class('abc');
+
+        ----
+        <?php
+
+        namespace Humbug\Acme;
+
+        class BplaaYai
+        {
+        }
+        $class = 'Humbug\Acme\BplaaYai';
+        new $class('abc');
+
+        PHP,
+
+    'new parent is an anonymous class' => <<<'PHP'
+        <?php
+        namespace Acme;
+
+        class BplaaYai {}
+
+        new class('abc') {};
+
+        ----
+        <?php
+
+        namespace Humbug\Acme;
+
+        class BplaaYai
+        {
+        }
+        new class('abc')
+        {
+        };
+
+        PHP,
 ];

src/PhpParser/NodeVisitor/StringScalarPrefixer.php

@@ -212,11 +212,10 @@ private function prefixNewStringArg(String_ $string, New_ $newNode): String_
     {
         $class = $newNode->class;
 
-        if (!($class instanceof Name)) {
-            throw UnexpectedParsingScenario::create();
-        }
-
-        if (in_array(strtolower($class->toString()), self::DATETIME_CLASSES, true)) {
+        if ($class instanceof Name
+            && in_array(strtolower($class->toString()), self::DATETIME_CLASSES, true)
+        ) {
+            // Value cannot be a class name, hence we should not try to prefix it.
             return $string;
         }