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`roave/you-are-using-it-wrong` complains about use of internal methods when token type is tested with `instanceof`

This is probably more of a psalm bug than anything else (or maybe I'm actually using it wrong), but I'm filing here just in case. I'm speculating that testing a token with instanceof causes psalm to either lose the intersection with the Token interface or, for whatever reason, the interface methods have a lower precedence after instanceof. So, calling getValue() on a token, such as Delimiter, causes psalm to look at the methods on the BasicToken class, which is declared as @internal, instead of the Token interface, which results in psalm emitting errors.

The work around is to create a psalm config file, regardless of whether the project uses psalm or not, which will cause roave/you-are-using-it-wrong to skip checks during installation.

Steps to reproduce:

  1. The calling code must reside in a different namespace (i.e. not Girgias\CSSParser)
  2. The calling code must test the type of the token using instanceof on a token that does not override it's base class' methods (most tokens extending BasicToken are candidates here)
  3. The project must not have a psalm configuration file, so that roave/you-are-using-it-wrong gets invoked
  4. Run composer install/update on the project

Sample code:

<?php

declare(strict_types=1);

namespace Vendor\TestPkg;

use Girgias\CSSParser\CompleteLexer;
use Girgias\CSSParser\SpecificationCompliantInputStream;
use Girgias\CSSParser\SpecificationCompliantLexer;
use Girgias\CSSParser\Tokens\Delimiter;
use Girgias\CSSParser\Tokens\EOF;

class App
{
    public function run()
    {
        $input = new SpecificationCompliantInputStream('#div');
        $lexer = new SpecificationCompliantLexer(new CompleteLexer($input));

        do {
            $token = $lexer->readNext();

            if ($token instanceof Delimiter && $token->getValue() === '+') {
                // do some stuff...
            }
        } while (!$token instanceof EOF);
    }
}
$ composer update
...

roave/you-are-using-it-wrong: checking strictly type-checked packages...
roave/you-are-using-it-wrong: following package usages will be checked:
 - girgias/css3-parser
 - - Girgias\CSSParser\

ERROR: InternalMethod - test_pkg/src/App.php:23:56 - The method Girgias\CSSParser\Tokens\BasicToken::getValue is internal to Girgias but called from Vendor\TestPkg\App (see https://psalm.dev/175)
            if ($token instanceof Delimiter && $token->getValue() === '+') {

Its not clear to me what should happen when a non-internal interface is implemented by an object that is marked as internal. Should the interface override the internalness of the object that implements it or should the interface inherit the implementing object's internalness?