Update required PHP and platform PHP.

[barryhughes]

• Our composer.json and the currently committed composer.lock are out of sync.
• We can't update various dependencies, because we (were) setting the platform PHP version to 5.6.
• We now expect and require PHP 7.0 as a minimum, so this should be reflected in these files.

[barryhughes]

Part of the motivation here is to resolve a class of CI errors that are blocking various tests.

[coreymckrill]

Given that WordPress itself requires a minimum of PHP 7.2, could we bump these numbers further up?

[coreymckrill]

Er, our support policy here is WP - 2, right? WordPress supported PHP 7.0 until 6.6, so I guess if we want to peg to WP's minimum requirements, we can't bump past 7.0 quite yet.

[coreymckrill]

Why would this not be the same value as require?

[barryhughes]

To satisfy the constraints of our current PHPUnit requirement (PHPUnit 7.5.20 asks for PHP 7.1+). In CI this isn't an issue, because if we are in a part of the test matrix specifying PHP 7.0 then we detect that and install PHPUnit 5.7 instead.

[barryhughes]

(Reference)

[barryhughes]

You can possibly get a better sense of what's happening if you checkout the current trunk branch, remove the Composer lock file, and run composer i.

[coreymckrill]

Ah, I see!

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Root composer.json requires woocommerce/woocommerce-sniffs 0.1.0 -> satisfiable by woocommerce/woocommerce-sniffs[0.1.0].
    - woocommerce/woocommerce-sniffs 0.1.0 requires php >=7.0 -> your php version (5.6; overridden via config.platform, actual: 8.3.9) does not satisfy that requirement.
  Problem 2
    - phpunit/phpunit[7.5.0, ..., 7.5.20] require php ^7.1 -> your php version (5.6; overridden via config.platform, actual: 8.3.9) does not satisfy that requirement.
    - Root composer.json requires phpunit/phpunit ^7.5 -> satisfiable by phpunit/phpunit[7.5.0, ..., 7.5.20].

[barryhughes]

Er, our support policy here is WP - 2, right?

Yep, L-2, so we generally need to match WP 6.4 in terms of minimum supported PHP.