PHP 8.4

[zerocrates]

8.4 is in its RC cycle and there seem to be a couple changes that are going to be annoying for us, in particular one that deprecates all usages of typehinted parameters in arguments that have null as a default, those are now supposed to have a question mark on the typehint to explicitly say the parameter is nullable.

It's not a problem for us to fix our own usages: the necessary version to add nullability is 7.1, well under our requirement, and there's a good autofixer for this from php-cs-fixer we can use.

The problem is going to be dependencies: this problem exists all over the place in Laminas code for example (and probably other dependencies), and some packages haven't yet been updated. We'll keep an eye out on that as those will probably fall into place as the release gets closer or soon after. The bigger issue will be that we'll likely have to increase our own minimum version to be able to update to these... 8.1 or higher is likely to be necessary to pull in new versions of things, up from our current 7.4 requirement.

The 8 series is quite widespread so it's probably not a huge issue, but I don't love dropping multiple versions of support in what would be a minor release for us. Particularly if we're approaching our own release and we don't have fixes in hand from all dependencies, we may instead have to look at adjusting error_reporting to exclude deprecations temporarily.