Fix the prefixing of returned string literals (#292)

Closes #291

Author: theofidry

specs/string-literal/return.php.php

@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the humbug/php-scoper package.
+ *
+ * Copyright (c) 2017 Théo FIDRY <[email protected]>,
+ *                    Pádraic Brady <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+return [
+    'meta' => [
+        'title' => 'Scalar literal returned',
+        // Default values. If not specified will be the one used
+        'prefix' => 'Humbug',
+        'whitelist' => [],
+        'whitelist-global-constants' => true,
+        'whitelist-global-classes' => false,
+        'whitelist-global-functions' => true,
+        'registered-classes' => [],
+        'registered-functions' => [],
+    ],
+
+    'String argument' => <<<'PHP'
+<?php
+
+function () {
+    return 'Symfony\\Component\\Yaml\\Ya_1';
+};
+
+function () {
+    return '\\Symfony\\Component\\Yaml\\Ya_1';
+};
+
+function () {
+    return 'Humbug\\Symfony\\Component\\Yaml\\Ya_1';
+};
+
+function () {
+    return '\\Humbug\\Symfony\\Component\\Yaml\\Ya_1';
+};
+
+function () {
+    return 'Closure';
+};
+
+function () {
+    return 'usedAttributes';
+};
+
+function () {
+    return 'FOO';
+};
+
+function () {
+    return 'PHP_EOL';
+};
+
+----
+<?php
+
+namespace Humbug;
+
+function () {
+    return 'Humbug\\Symfony\\Component\\Yaml\\Ya_1';
+};
+function () {
+    return 'Humbug\\Symfony\\Component\\Yaml\\Ya_1';
+};
+function () {
+    return 'Humbug\\Symfony\\Component\\Yaml\\Ya_1';
+};
+function () {
+    return 'Humbug\\Symfony\\Component\\Yaml\\Ya_1';
+};
+function () {
+    return 'Closure';
+};
+function () {
+    return 'usedAttributes';
+};
+function () {
+    return 'FOO';
+};
+function () {
+    return 'PHP_EOL';
+};
+
+PHP
+    ,
+];

src/PhpParser/NodeVisitor/StringScalarPrefixer.php

@@ -28,6 +28,7 @@
 use PhpParser\Node\Param;
 use PhpParser\Node\Scalar\String_;
 use PhpParser\Node\Stmt\PropertyProperty;
+use PhpParser\Node\Stmt\Return_;
 use PhpParser\NodeVisitorAbstract;
 use function array_key_exists;
 use function array_shift;
@@ -122,6 +123,7 @@ private function prefixStringScalar(String_ $string): String_
                 || $parentNode instanceof Param
                 || $parentNode instanceof Const_
                 || $parentNode instanceof PropertyProperty
+                || $parentNode instanceof Return_
             )
         ) {
             return $string;