Dynamic return types in PHP

Question

I'm trying to implement something like the Repository of Doctrine does. I do not interact with a database but need to fetch data from sources.

I have an AbstractRepository and want to have an autocompletion in PhpStorm based on the class given in the constructor. Here is some code:

/**
 * @template T
 */
abstract class AbstractRepository
{
    /**
     * @psalm-var class-string<T>
     */
    protected $className;

    public function __construct(string $className)
    {
        $this->className = $className;
    }

    /*
     * @psalm-return ?T
     */
    public function findById(string $id)
    {
        // do some calls and return an actual model based on the classname
    }
}

class FooRepository extends AbstractRepository
{
    public function __construct()
    {
        parent::__construct(MyModel::class);
    }
}

(new FooRepository())->findById('bar'); // PHPStorm should typehint as MyModel

But PhpStorm just says mixed|null.

What am I doing wrong?

Answer 1

With PHPStorm, you have to use the DynamicReturnTypePlugin to get the autocompletion on return types depending on the function parameters.

https://plugins.jetbrains.com/plugin/7251-dynamicreturntypeplugin