Bump the minimum PHP version supported

[theofidry]

Currently PHPBrew supports 7.2. It was released in November 2017 and has been EOL since November 2020.

The PHPBrew codebase is a bit hard to follow and contribute to and I think requiring the code to be compatible with such an old PHP version does not help it.

Most of the time it is fairly easy to install a relatively recent version of PHP on your machine, the value of PHPBrew IMO is to either be able to create a PHP binary tailored to your needs (with specific extensions) or install an older PHP version which may be EOL and require user-land patches because it will no longer be patched in PHP itself.

So I think for most of the users, bumping the PHP version used will not hurt the adoption.

I would also add that there is alternatives:

• Rector provides a tool to downgrade the code to some degree (I do not know to what extend it manages to do that, but I know PHPStan relies on it to make its codebase 7.2 compatible without limiting its codebase to PHP 7.2 features only).
• It could be possible to ship a PHAR with a static PHP binary (I am working on bringing that to Box), which would make the version used by PHPbrew entirely irrelevant.

So given PHPbrew struggles in terms of contribution, what do you think of bumping the minimal version to PHP 8.3 (8.1 is reaching EOL at the end of the year) and if more means are available at a later time to work out an alternative path to add a wider range of supported PHP versions?

[theofidry]

I would also add: this is not only the source code, but also for the unit tests: it is much easier to write tests with newer versions of PHP and where you only have to worry about one version of PHPUnit rather than having to write PHP 7.2 compatible tests with PHPUnit that ranges from 8 to 11 (and all but latest being unmaintained) because it is not compatible with such a wide range of versions.