ComposerClassLocator.php

<?php

declare(strict_types=1);

namespace ExtendedTypeSystem\Reflection\ClassLocator;

use Composer\Autoload\ClassLoader;
use ExtendedTypeSystem\Reflection\ClassLocator;
use ExtendedTypeSystem\Reflection\Source;

/**
 * @api
 */
final class ComposerClassLocator implements ClassLocator
{
    public function locateClass(string $class): ?Source
    {
        foreach (ClassLoader::getRegisteredLoaders() as $classLoader) {
            $file = $classLoader->findFile($class);

            if ($file !== false) {
                return Source::fromFile($file, 'composer autoloader');
            }
        }

        return null;
    }
}

ComposerClassLocatorTest.php

<?php

declare(strict_types=1);

namespace ExtendedTypeSystem\Reflection\ClassLocator;

use ExtendedTypeSystem\Reflection\Source;
use PHPUnit\Framework\Attributes\CoversClass;
use PHPUnit\Framework\TestCase;

/**
 * @internal
 */
#[CoversClass(ComposerClassLocator::class)]
final class ComposerClassLocatorTest extends TestCase
{
    public function testItLocatesClass(): void
    {
        $expectedSource = Source::fromFile(__FILE__, 'composer autoloader');
        $locator = new ComposerClassLocator();

        $locatedSource = $locator->locateClass(self::class);

        self::assertEquals($expectedSource, $locatedSource);
    }

    public function testItReturnsNullForInternalClass(): void
    {
        $locator = new ComposerClassLocator();

        $locatedSource = $locator->locateClass(\stdClass::class);

        self::assertNull($locatedSource);
    }
}