Add @param-out for wp_parse_str()

[IanDelMar]

Currently, no tests have been added as PHPStan requires bleeding edge to be enabled in order not to discard the type provided via @param-out.

Assertions might look like

// tests/data/wp_parse_str.php

declare(strict_types=1);

namespace PhpStubs\WordPress\Core\Tests;

use function wp_parse_str;
use function PHPStan\Testing\assertType;

// The type of `$result` cannot be narrowed further via stubs.
wp_parse_str('key=value');
assertType('array<int|string, array|string>', $result);
wp_parse_str('key1[key2]]=value');
assertType('array<int|string, array|string>', $result);

[szepeviktor]

The docs say it needs a parameter name https://phpstan.org/writing-php-code/phpdocs-basics#setting-parameter-type-passed-by-reference

[IanDelMar]

Of course.

[johnbillion]

I think it's worth using the phpstan- prefix on these tag names so it's clear what they are for. Especially as this is a new phpstan feature.

[johnbillion]

Oh not that new actually. But still.