feat: use generic types for deserialization

[scyzoryck]

Q	A
Bug fix?	no
New feature?	yes
Doc updated	no
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets
License	MIT

It looks like right now to have a proper type hints for it required additional plugin. Inspired by: https://phpstan.org/blog/generics-by-examples it allowed to use generics for type hinting.

Debug file

<?php

declare(strict_types=1);

namespace JMS\Serializer\Tests;

use JMS\Serializer\SerializerBuilder;
use JMS\Serializer\Tests\Fixtures\Author;

$serializer = SerializerBuilder::create()->build();
$d = $serializer->deserialize('{}', Author::class, 'json' );
\PHPStan\dumpType($d); // MyDerivative :)

$serializer = SerializerBuilder::create()->build();
$d = $serializer->deserialize('{}', Author::class . '[]', 'json' );
\PHPStan\dumpType($d); //

Before

 ------ ----------------------------------------------------- 
  Line   PHPStanTypesTest.php                                 
 ------ ----------------------------------------------------- 
  13     Dumped type: mixed
  18     Dumped type: mixed
 ------ ----------------------------------------------------- 

After

 ------ ----------------------------------------------------- 
  Line   PHPStanTypesTest.php                                 
 ------ ----------------------------------------------------- 
  13     Dumped type: JMS\Serializer\Tests\Fixtures\Author    
  18     Dumped type: JMS\Serializer\Tests\Fixtures\Author[]  
 ------ ----------------------------------------------------- 

[goetas]

This was already implemented in the past and reverted. It does not work well when the de-serialized type is an array or objects.

I use this extension to provide the return type in this case https://github.com/goetas/jms-serializer-phpstan-extension