Proposal 1:

There are certain tokenizer quirks - especially around the changes in integers, like binary integers (5.4) and numeric literals with underscores (7.4) - which are making supporting PHP 5.3 more and more complicated.

I'd like to propose for PHPCompatibility to drop PHP 5.3 support once PHP 7.4 comes out.
The new minimum PHP version will then be PHP 5.4 which is still ancient.

PHP 5.4 has already been the minimum recommended PHP version since June 2017 (619cb41).

In anticipation of this, I'd like to suggest adding a PHPCompatibility.Upgrade.LowPHP sniff to warn people who are still running PHPCompatibility on PHP 5.3 about the impending change in the minimum requirements.

Proposal 2:

Along the same lines, I'd like to propose we drop support for PHP_CodeSniffer < 2.6.0 at the same time.

PHP_CodeSniffer 2.6.0 has already been the minimum recommended PHPCS version for PHPCompatibility since August 2016 (5598f60).

Additionally, the LowPHPCS upgrade warning sniff has been in place since July 2018 and has not generated any support requests

Open questions:

If this proposal is accepted, it would be a good idea to set new (higher) recommended PHP and PHPCS versions when the version drop is implemented.

I'd like to suggest the following for those:

• PHP: 5.6
• PHPCS: 3.1.0