[TypeDeclaration] Add false and true in union support on ReturnUnionTypeRector

[samsonasik]

This PR make:

• on php 8.0 until php 8.1: false|string is allowed, combine true and string become bool|string
• on >= php 8.2: false|string and true|string is allowed

ref

• false|string: https://3v4l.org/KSofT
• true|string: https://3v4l.org/UJqXT

[samsonasik]

By this, I found a bug on ReturnTypeFromStrictTernaryRector, which 2 PHPStan\Type\Constant\ConstantStringType marked as union, which invalid

https://github.com/rectorphp/rector-src/actions/runs/7172210877/job/19528876575?pr=5355#step:5:90

array (2)
   0 => PHPStan\Type\Constant\ConstantStringType #9554
   |  value: 'hey'
   |  isClassString: false
   |  objectType: null
   |  arrayKeyType: null
   1 => PHPStan\Type\Constant\ConstantStringType #9560
   |  value: 'hou'
   |  isClassString: false
   |  objectType: null
   |  arrayKeyType: null

On use case:

final class LocalConstants
{
    const FIRST = 'hey';
    const SECOND = 'hou';

    public function getValue($number)
    {
        return $number ? self::FIRST : self::SECOND;
    }
}

the issue seems on TypeFactory::uniquateTypes()

rector-src/packages/NodeTypeResolver/PHPStan/Type/TypeFactory.php

Line 59 in dc9573d

public function uniquateTypes(array $types, bool $keepConstant = false): array

[samsonasik]

It seems resolved with remove value to be included in hash on TypeHasher 22db784

[samsonasik]

I added failing fixture for both false and true in union, to be bool.

[TomasVotruba]

@samsonasik What needs to be done here to finish/close this one? I'd like to resolve it before next release

[samsonasik]

it currently only phpstan complexity https://github.com/rectorphp/rector-src/actions/runs/7172780220/job/19530707952?pr=5355#step:5:19 , but I may missing something on hash uniquite types

I can rebase and extract method/ignore in phpstan.neon after psr4 work, it seems still error on scoped build

https://github.com/rectorphp/rector-src/actions/runs/7378601824/job/20073924556#step:11:38

[samsonasik]

All checks have passed 🎉 @TomasVotruba I think it is ready.

[samsonasik]

@TomasVotruba let's merge it to have faster feedback to test ;)