fix: #3585723 #date_year_range does not support years < 1000

    $this_year = $datetime->format('Y');

    [$min_year, $max_year] = explode(':', $string);

    // Valid patterns would be -5:+5, 0:+1, 2008:2010.

    // Valid patterns would be -5:+5, +0:+1, 2008:2010, 1:9999.

    // Note that year 0 is 0 while current year is: +0.

    // Due to the +/- logic we can't support years BC (<0).

    $plus_pattern = '@[\+|\-][0-9]{1,4}@';

    $year_pattern = '@^[0-9]{4}@';

    $year_pattern = '@^[0-9]{1,4}@';

    if (!preg_match($year_pattern, $min_year, $matches)) {

      if (preg_match($plus_pattern, $min_year, $matches)) {

        $min_year = $this_year + $matches[0];

<?php

declare(strict_types=1);

namespace Drupal\Tests\Core\Datetime\Element;

use Drupal\Core\Datetime\Element\DateElementBase;

use Drupal\Core\Language\LanguageInterface;

use Drupal\Core\Language\LanguageManagerInterface;

use Drupal\Tests\UnitTestCase;

use PHPUnit\Framework\Attributes\DataProvider;

use PHPUnit\Framework\Attributes\Group;

use Symfony\Component\DependencyInjection\ContainerBuilder;

/**

 * Tests the DateElementBase class.

 */

#[Group('Datetime')]

class DateElementBaseTest extends UnitTestCase {

  /**

   * {@inheritdoc}

   */

  protected function setUp(): void {

    parent::setUp();

    $language = $this->createStub(LanguageInterface::class);

    $language->method('getId')->willReturn('en');

    $language_manager = $this->createStub(LanguageManagerInterface::class);

    $language_manager->method('getCurrentLanguage')->willReturn($language);

    $container = new ContainerBuilder();

    $container->set('language_manager', $language_manager);

    \Drupal::setContainer($container);

  }

  /**

   * Tests datetimeRangeYears() with various year range strings.

   *

   * @param string $range

   *   The year range string to test.

   * @param int $expected_min

   *   The expected minimum year.

   * @param int $expected_max

   *   The expected maximum year.

   */

  #[DataProvider('providerTestDatetimeRangeYears')]

  public function testDatetimeRangeYears(

    string $range,

    int $expected_min,

    int $expected_max,

  ): void {

    $method = new \ReflectionMethod(DateElementBase::class, 'datetimeRangeYears');

    /** @var array{string, string} $result */

    $result = $method->invoke(NULL, $range);

    [$min, $max] = $result;

    $this->assertSame($expected_min, (int) $min);

    $this->assertSame($expected_max, (int) $max);

  }

  /**

   * Data provider for testDatetimeRangeYears().

   */

  public static function providerTestDatetimeRangeYears(): array {

    $this_year = (int) date('Y');

    return [

      'standard 4-digit range' => ['1900:2050', 1900, 2050],

      'year less than 1000' => ['500:1500', 500, 1500],

      'year zero as min' => ['0:2050', 0, 2050],

      'both years less than 1000' => ['0:999', 0, 999],

      'single digit year' => ['1:9999', 1, 9999],

      'relative max' => ['1900:+0', 1900, $this_year],

      'year zero with relative max' => ['0:+50', 0, $this_year + 50],

      'both relative' => ['-5:+5', $this_year - 5, $this_year + 5],

      'both year zero' => ['0:0', 0, 0],

      'both this year (+0)' => ['+0:+0', $this_year, $this_year],

      'both this year (-0)' => ['-0:-0', $this_year, $this_year],

      'negative four digit year' => ['-1000:-0', $this_year - 1000, $this_year],

      'negative three digit year' => ['-100:-1', $this_year - 100, $this_year - 1],

      'negative two digit year' => ['-10:-1', $this_year - 10, $this_year - 1],

    ];

  }

}