Prefix strings

README.md

@@ -44,6 +44,7 @@ potentially very difficult to debug due to dissimilar or unsupported package ver
     - [Step 3: Build, test, and cleanup](#step-3-build-test-and-cleanup)
 - [Limitations](#limitations)
     - [PSR-0 support](#psr-0-support)
+    - [String values](#string-values)
 - [Contributing](#contributing)
 - [Credits](#credits)
 
@@ -415,6 +416,27 @@ add a significant overhead besides being more complex. As a result PHP-Scoper do
 support the exotic case above.
 
 
+### String values
+
+PHP-Scoper tries whenever possible to prefix strings as well:
+
+```php
+class_exists('Acme\Foo');
+
+// Will be prefixed into:
+
+\class_exists('Humbug\Acme\Foo');
+```
+
+PHP-Scoper uses a regex to determine if the string is a class name that must be prefixed. But there is
+bound to have confusing cases. For example:
+
+- If you have a plain string `'Acme\Foo'` which has nothing to do with a class, PHP-Parser will not be
+  able to tell and will prefix it
+- Classes belonging to the global scope: `'Acme_Foo'`, because there is no way to know if it is a class
+  name or a random string.
+
+
 ## Contributing
 
 [Contribution Guide](CONTRIBUTING.md)

specs/string-literal/array-var.php

@@ -0,0 +1,42 @@
+<?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 assigned as key or value in an array',
+        // Default values. If not specified will be the one used
+        'prefix' => 'Humbug',
+        'whitelist' => [],
+    ],
+
+    'String argument: transform into a FQCN and prefix it' => <<<'PHP'
+<?php
+
+$x = [
+    'Symfony\\Component\\Yaml\\Yaml' => 'Symfony\\Component\\Yaml\\Yaml',
+    '\\Symfony\\Component\\Yaml\\Yaml' => '\\Symfony\\Component\\Yaml\\Yaml',
+    'Humbug\\Symfony\\Component\\Yaml\\Yaml' => 'Humbug\\Symfony\\Component\\Yaml\\Yaml',
+    '\\Humbug\\Symfony\\Component\\Yaml\\Yaml' => '\\Humbug\\Symfony\\Component\\Yaml\\Yaml',
+];
+
+----
+<?php
+
+namespace Humbug;
+
+$x = ['Humbug\\Symfony\\Component\\Yaml\\Yaml' => 'Humbug\\Symfony\\Component\\Yaml\\Yaml', 'Humbug\\Symfony\\Component\\Yaml\\Yaml' => 'Humbug\\Symfony\\Component\\Yaml\\Yaml', 'Humbug\\Symfony\\Component\\Yaml\\Yaml' => 'Humbug\\Symfony\\Component\\Yaml\\Yaml', 'Humbug\\Symfony\\Component\\Yaml\\Yaml' => 'Humbug\\Symfony\\Component\\Yaml\\Yaml'];
+
+PHP
+    ,
+];