Do I need the highest PHP version to downgrade?

[shyim]

Question

I would give the downgrade possibility a try and got fast a hidden error:

Analyze error: "ParseError (syntax error, unexpected 'private' (T_PRIVATE), expecting variable (T_VARIABLE)) thrown while looking for class Frosh\MailArchive\Controller\Api\MailResendController."
```

From the internal error, I assume that I will need PHP 8.0 on cli to downgrade the code from 8.0 to 7.4? Is that right?

Maybe makes sense to check the used PHP version in the CLI then when that set / etc is active 🤔 

[shyim]

Hmm after using PHP 8 on the CLI it works. A RuntimeException would be awesome when the running PHP is below the set

[sabbelasichon]

If you want to downgrade from PHP 8 to PHP 7.4 PHP 8 is needed. True.
Could you provide a solution for better / clearer communication?

[shyim]

Hmm difficult as the set used doesn't matter. Maybe extending the error with a message like: The file couldn't be parsed. This could be a Syntax error or the used PHP to run rector can't read the file.

Btw: Should the Reflection Class stuff doesn't execute the PHP code? 🤔

[sabbelasichon]

We are using Static Reflection here, so no execution involved.

[TomasVotruba]

The downgrade should work even from version bellow.
It's possible Rector is autoloading projects' vendor/autoload.php. Then the class is invoked from the project and not loaded by static reflection.

Could you provide minimal reproducible repository with failing Github action with the downgrade? We'll be able to help then

[sabbelasichon]

I am surprised, that this is possible. Downgrade from PHP 8 to let´s say to PHP 7.4 by running 7.4. Is this possible due to static reflection? Otherwise i would say, we can close this issue here.

[shyim]

I have packed it as zip. I tried debug_print_backtrace() but couldn't find a caller.

Zip: https://drive.google.com/file/d/183efpMwiW2nmUWz_kfRq92IqOR5OMlMd/view?usp=sharing

Unpack it and run: rector process -c rector.php src/ -a vendor/autoload.php -vvv
You will see then the error: [printing skipped due error] src/Controller/Api/MailResendController.php on PHP 7.4 and with 8.0 it works

[TomasVotruba]

@shyim At the moment we'll stick with a practise to use the same PHP we downgrade code. The composer install must run on such project anyway. If you don't have such PHP locally and that's a blockre, you can use the GitHub Actions like we do in Rector.

Downgrade from PHP 8 to let´s say to PHP 7.4 by running 7.4. Is this possible due to static reflection? Otherwise i would say, we can close this issue here.

Agreed, we can close it.