Enum-like example

ContractStatus.php

<?php

use Library\EnumLike;

class ContractStatus extends EnumLike
{
    const ACTIVE = 'active';

    const STOPPING = 'stopping';

    const STOPPED = 'stopped';

    const TERMINATED = 'terminated';

    public static function active() : self
    {
        return new self(self::ACTIVE);
    }

    public static function stopping() : self
    {
        return new self(self::STOPPING);
    }

    public static function stopped() : self
    {
        return new self(self::STOPPED);
    }

    public static function terminated() : self
    {
        return new self(self::TERMINATED);
    }
}

EnumLike.php

<?php

namespace Library;

abstract class EnumLike
{
    protected $value;

    protected function __construct(string $value)
    {
        $this->value = $value;
    }

    public function __toString() : string
    {
        return $this->value;
    }
}

EnumLikeTest

<?php

namespace Tests;

use Library\EnumLike;
use PHPUnit\Framework\TestCase;

class EnumLikeTest extends TestCase
{
    public function testEnumLike()
    {
        $enumLike = MyEnum::value();

        $this->assertEquals(MyEnum::VALUE, $enumLike);
    }
}

class MyEnum extends EnumLike
{
    const VALUE = 'value';

    public static function value()
    {
        return new self(self::VALUE);
    }
}