CompactSerializerTest.php

<?php

declare(strict_types=1);

namespace Jose\Tests\Component\Encryption;

use InvalidArgumentException;
use Jose\Component\Encryption\Serializer\CompactSerializer;
use PHPUnit\Framework\Attributes\Test;
use PHPUnit\Framework\TestCase;
use function memory_get_peak_usage;
use function memory_get_usage;
use function memory_reset_peak_usage;
use function str_repeat;

/**
 * @internal
 */
final class CompactSerializerTest extends TestCase
{
    #[Test]
    public function aTokenWithTooManySegmentsIsRejected(): void
    {
        $this->expectException(InvalidArgumentException::class);
        $this->expectExceptionMessage('Unsupported input');

        (new CompactSerializer())->unserialize('eyJhbGciOiJkaXIiLCJlbmMiOiJBMTI4R0NNIn0.....');
    }

    /**
     * A delimiter-heavy token must be rejected without expanding it into one array entry per delimiter. The
     * threshold is deliberately generous: the unbounded split of this input allocates roughly twenty-five times its
     * size, while the bounded one stays proportional to it.
     */
    #[Test]
    public function aDelimiterHeavyTokenIsRejectedWithoutExhaustingMemory(): void
    {
        $token = str_repeat('.', 2_000_000);
        $serializer = new CompactSerializer();
        memory_reset_peak_usage();
        $before = memory_get_usage();

        try {
            $serializer->unserialize($token);
            static::fail('The token should have been rejected.');
        } catch (InvalidArgumentException $e) {
            static::assertSame('Unsupported input', $e->getMessage());
        }

        static::assertLessThan(8_000_000, memory_get_peak_usage() - $before);
    }
}