ExplicitNullableParamTypeRector can be applied from PHP 7.1

[GromNaN]

PHP 8.4 deprecates implicit nullable parameters, but the transformation can be applied with PHP 7.1+ compatibility.

This change is necessary in order to use the ExplicitNullableParamTypeRector with projects that allows PHP < 8.3 (i.e. all projects that currently exist), to make them compatible with PHP 8.4.

[GromNaN]

This constant becomes unused, but is part of the API, I don't know if you want to keep it.

[GromNaN]

Here's how I used this rule to create this PR felixfbecker/php-language-server-protocol#22

Install rector:
composer require --dev rector/rector

Setup the config with only one rule:

<?php

return Rector\Config\RectorConfig::configure()
    ->withPaths([__DIR__ . '/src'])
    ->withRules([Rector\Php84\Rector\Param\ExplicitNullableParamTypeRector::class]);

And run vendor/bin/rector.

Without change, nothing is fixed since the project requires php >= 7.1.

[samsonasik]

I don't want to enforce something that not deprecated to begin with, so it needs to be php 8.4.

Feel free to copy and modify as your own custom rule.

Thank you for understanding.

[GromNaN]

Please read my comment. The rule can't be applied to projects that support PHP 8.4.
I think it's a bad strategy to ask everyone to fork the rule when there are hundreds of libraries to fix and rector is the best tool for that.

Maybe there is an other solution to allow using this rule without enforcing it.

[samsonasik]

Php 8.4 is not yet released, however, you should can enforce via config:

->withPhpVersion(PhpVersion::PHP_84)

[GromNaN]

Ok, thanks for that clarification.

[samsonasik]

No worries, btw, the better way is to create new release and new compatible code once php 8.4 released, that's ensure nothing left behind, and not accidentally applied syntax that not yet supported.

[GromNaN]

The "new" syntax is supported since PHP 7.1, which is 8 years old. Most of the actively supported libraries already dropped older PHP versions.

[GromNaN]

I wrote a tutorial for those concerned: https://dev.to/gromnan/fix-php-84-deprecation-implicitly-marking-parameter-as-nullable-is-deprecated-the-explicit-nullable-type-must-be-used-instead-5gp3