minor: add test for fallback dirs

phpunit.xml.dist

@@ -10,6 +10,7 @@
     </testsuite>
     <testsuite name="Functional tests">
       <directory suffix=".phpt">tests/functional/error-handler/</directory>
+      <file>tests/functional/fallback-dirs/test.phpt</file>
       <file>tests/functional/invalid-class/test.phpt</file>
       <file>tests/functional/nested-composer-projects/test.phpt</file>
       <file>tests/issue-13/test.phpt</file>

tests/functional/fallback-dirs/composer.json

@@ -0,0 +1,15 @@
+{
+    "repositories": [
+        {
+            "type": "vcs",
+            "url": "../../.."
+        }
+    ],
+    "autoload": {
+        "Kcs\\ClassFinder\\FunctionalTests\\": "src/"
+    },
+    "require": {
+        "kcs/class-finder": "dev-master",
+        "symfony/string": "*"
+    }
+}

tests/functional/fallback-dirs/fall/Symfony/Component/String/LazyString.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Symfony\Component\String;
+
+class LazyString implements \Stringable, \JsonSerializable
+{
+
+    public function __toString(): string
+    {
+        return 'test';
+    }
+
+    public function jsonSerialize(): mixed
+    {
+        return [];
+    }
+}

tests/functional/fallback-dirs/src/Foobar.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Kcs\ClassFinder\FunctionalTests;
+
+class Foobar
+{
+}

tests/functional/fallback-dirs/test.phpt

@@ -0,0 +1,17 @@
+--TEST--
+Fallback directories
+--INI--
+error_reporting=E_ALL & ~E_NOTICE & ~E_DEPRECATED
+--FILE--
+<?php
+require_once __DIR__ . '/vendor/autoload.php';
+
+$finder = (new Kcs\ClassFinder\Finder\ComposerFinder())->skipBogonFiles();
+$arr = iterator_to_array($finder);
+
+/** @var ReflectionClass $class */
+$class = $arr[\Symfony\Component\String\LazyString::class];
+echo str_replace(DIRECTORY_SEPARATOR, '/', $class->getFileName());
+?>
+--EXPECTF--
+%s/tests/functional/fallback-dirs/vendor/symfony/string/LazyString.php