Use TypeUtils::getOldConstantArrays in array_reduce extension

[herndlm]

This is only doing emptyness checks and for that optional keys don't need to be considered AFAIK.

[herndlm]

What if I eventually manage to get rid of all getConstantArrays? Deprecate it? Not in favor of the internal getOldConstantArray I guess? 😅

One of my plans is to try to get rid of ConstantArrayType::powerSet as much as possible, preferable make it hard to use it indirectly. But there's still a bit of work needed for that. And a plan of what to use instead then for e.g. ConstantArrayType::getAllArrays, TypeUtils::flattenTypes, TypeUtils::getArrays, and of course TypeUtils::getConstantArrays. Good thing though is: some of them are rarely used yet.

[ondrejmirtes]

I'd expect to deprecate both methods on TypeUtils and just introduce Type::getConstantArrays() that would basically behave the same way as getOldConstantArrays and would be a drop-in replacement.

Yeah, and deprecate places that call powerSet too.

[herndlm]

sounds like a plan and I have a goal then :) sorry for jumping between things btw, but this here is bugging me also for a while already..

[ondrejmirtes]

Thank you!