[Bug]: Pest + PHP Matcher = simplexml_load_string(): Entity: line 1: parser error : Start tag expected, '<' not found

[mdacosta]

What Happened

When I want to do some JSON assertions using PHP Matcher, the tests passes, but there is a warning : simplexml_load_string(): Entity: line 1: parser error : Start tag expected, '<' not found

The exact same test written in PHPUnit style runs without any warning :

How to Reproduce

• create a new PHP project
• install coduo/php-matcher
• install Pest

Sample Repository

https://github.com/mdacosta/pest-issue

Pest Version

2.34.8

PHP Version

8.3.7, 8.3.8

Operation System

macOS, Linux

Notes

Pest test :

<?php

declare (strict_types = 1);

use Coduo\PHPMatcher\PHPUnit\PHPMatcherConstraint;

test('example', function () {
    $data = [
        /* @lang JSON */
        '{
            "url": "/profile/01BX5ZZKBKACTAV9WEVGEMMVS0"
        }',
        /* @lang JSON */
        '{
            "url": "/profile/@ulid@"
        }',
    ];

    $this->assertThat($data[0], new PHPMatcherConstraint($data[1]));
});

PHPUnit test :

<?php

declare(strict_types=1);

namespace App\Tests;

use Coduo\PHPMatcher\PHPUnit\PHPMatcherConstraint;
use Coduo\PHPMatcher\PHPUnit\PHPMatcherTestCase;

class MatcherTest extends PHPMatcherTestCase
{
    public function test_matcher_with_json(): void
    {
        $data = [
            /* @lang JSON */
            '{
              "url": "/profile/01BX5ZZKBKACTAV9WEVGEMMVS0"
            }',
                /* @lang JSON */
                '{
                "url": "/profile/@ulid@"
            }',
        ];

        $this->assertThat($data[0], new PHPMatcherConstraint($data[1]));
    }
}

The issue comes from the fact that I want to do some assertions like this "url": "/profile/@ulid@".
I the string contains only a ULID, then doing this "url": "@ulid@" works fine.

The reason why I created this is issue here and not on PHPMatcher project is because it works with PHPUnit, which makes me think that there is something wrong with Pest.

This other reason why I think this is a Pest issue is that I already used Pest + PHP Matcher in the past, and it was working well. But it was Pest 1. Maybe something changed in Pest 2.