Mutation testing fails with "Psr\SimpleCache\CacheInterface cannot be resolved"

Mutation testing fails with "Psr\SimpleCache\CacheInterface cannot be resolved"

Description

Pest mutation testing fails during the mutation analysis phase with a ShouldNotHappen exception when trying to resolve Psr\SimpleCache\CacheInterface.

Environment

• Pest version: 4.3.1
• PHP versions tested: 8.4.16 and 8.5.1
• Operating system: macOS (Darwin)
• Laravel version: 12.x

Steps to Reproduce

1. Run mutation testing with the --everything --covered-only flags:

   vendor/bin/pest --mutate --everything --min=90 --covered-only
   
   

Expected Behavior

Mutation testing should complete and report the mutation score.

Actual Behavior

Tests pass successfully (430 passed, 1569 assertions), but mutation analysis fails with:

Pest\Exceptions\ShouldNotHappen

This should not happen - please create an new issue here: https://github.com/pestphp/pest/issues

Issue: A dependency with the name `Psr\SimpleCache\CacheInterface` cannot be resolved.
PHP version: 8.4.16
Operating system: Darwin

at vendor/pestphp/pest/src/Exceptions/ShouldNotHappen.php:37

Additional Context

• This occurs consistently on both PHP 8.4 and PHP 8.5
• Regular test runs (vendor/bin/pest) work without issues
• The project uses Laravel 12 with standard PSR-4 autoloading
• psr/simple-cache is installed as a dependency of Laravel

Composer dependencies (relevant)

{
    "require": {
        "laravel/framework": "^12.45.1"
    },
    "require-dev": {
        "pestphp/pest": "^4.3.1",
        "pestphp/pest-plugin-arch": "^4.0",
        "pestphp/pest-plugin-browser": "^4.1.1",
        "pestphp/pest-plugin-faker": "^4.0",
        "pestphp/pest-plugin-laravel": "^4.0",
        "pestphp/pest-plugin-type-coverage": "^4.0.3"
    }
}

Run vendor/bin/pest --mutate --everything --min=90 --covered-only and compare it with the regular vendor/bin/pest run. Start at vendor/pestphp/pest/src/Exceptions/ShouldNotHappen.php and trace the mutation-analysis failure while resolving Psr\SimpleCache\CacheInterface. Done means mutation testing completes and reports the mutation score.