<?php

declare(strict_types=1);

/**
 * This file is part of the Carbon package.
 *
 * (c) Brian Nesbitt <brian@nesbot.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Tests\CarbonImmutable;

use Carbon\Carbon as MutableCarbon;
use Carbon\CarbonImmutable as Carbon;
use ErrorException;
use Generator;
use PHPUnit\Framework\Attributes\DataProvider;
use PHPUnit\Framework\Attributes\RequiresPhp;
use Tests\AbstractTestCase;

#[RequiresPhp('>=8.5.0')]
class NoDiscardTest extends AbstractTestCase
{
    public static function dataForDiscardedCalls(): Generator
    {
        yield ['modify', ['+1 day']];
        yield ['next', []];
        yield ['previous', []];
        yield ['addDays', [2]];
    }

    #[DataProvider('dataForDiscardedCalls')]
    public function testDiscardedResultTriggersWarning(string $method, array $arguments): void
    {
        $this->expectException(ErrorException::class);
        $this->expectExceptionMessage(
            "The return value of method Carbon\\CarbonImmutable::$method() should either be used or intentionally ignored by casting it as (void)",
        );

        $date = Carbon::parse('2026-10-02 12:00');

        $this->withErrorAsException(static function () use ($date, $method, $arguments) {
            $date->$method(...$arguments);
        });
    }

    public function testMutableResultCanBeDiscarded(): void
    {
        $date = MutableCarbon::parse('2026-10-02 12:00');

        $this->withErrorAsException(static function () use ($date) {
            $date->modify('+1 day');
            $date->next();
            $date->addDays(2);
        });

        $this->assertSame('2026-10-12 00:00:00', $date->format('Y-m-d H:i:s'));
    }
}