test: check that incorrect classes don't trigger autoloading errors

Thanks @oprypkhantc

tests/Fixtures/BadNamespace/BadlyNamespacedClass.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace TheCodingMachine\GraphQLite\Fixtures\BadNamespace\None;
+
+class BadlyNamespacedClass
+{
+
+}

tests/Fixtures/BadNamespace/ClassWithoutNamespace.php

@@ -0,0 +1,5 @@
+<?php
+class ClassWithoutNamespace
+{
+
+}

tests/Utils/NsTest.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace TheCodingMachine\GraphQLite\Utils;
+
+use Kcs\ClassFinder\Finder\ComposerFinder;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Cache\Adapter\ArrayAdapter;
+use Symfony\Component\Cache\Psr16Cache;
+use TheCodingMachine\GraphQLite\Utils\Namespaces\NS;
+use TheCodingMachine\GraphQLite\Fixtures\Types\AbstractFooType;
+use TheCodingMachine\GraphQLite\Fixtures\Types\FooExtendType;
+use TheCodingMachine\GraphQLite\Fixtures\Types\FooType;
+use TheCodingMachine\GraphQLite\Fixtures\Types\GetterSetterType;
+use TheCodingMachine\GraphQLite\Fixtures\Types\MagicGetterSetterType;
+use TheCodingMachine\GraphQLite\Fixtures\Types\NoTypeAnnotation;
+use TheCodingMachine\GraphQLite\Fixtures\Types\TestFactory;
+
+class NsTest extends TestCase
+{
+    /**
+     * @dataProvider loadsClassListProvider
+     */
+    public function testLoadsClassList(array $expectedClasses, string $namespace): void
+    {
+        $ns = new NS(
+            namespace: $namespace,
+            cache: new Psr16Cache(new ArrayAdapter()),
+            finder: new ComposerFinder(),
+            globTTL: null
+        );
+
+        self::assertEqualsCanonicalizing($expectedClasses, array_keys($ns->getClassList()));
+    }
+
+    public static function loadsClassListProvider(): iterable
+    {
+        yield 'autoload' => [
+            [
+                TestFactory::class,
+                GetterSetterType::class,
+                FooType::class,
+                MagicGetterSetterType::class,
+                FooExtendType::class,
+                NoTypeAnnotation::class,
+                AbstractFooType::class,
+            ],
+            'TheCodingMachine\GraphQLite\Fixtures\Types',
+        ];
+
+        // The class should be ignored.
+        yield 'incorrect namespace class without autoload' => [
+            [],
+            'TheCodingMachine\GraphQLite\Fixtures\BadNamespace',
+        ];
+    }
+}