Support Ruby 3.2

[maneyko]

File.exists? and Dir.exists? have been removed in Ruby 3.2 in favor of File.exist? and Dir.exist?, respectively.

Both File.exist? and Dir.exist? have been around since Ruby 1.9.0, so backwards compatibility is not a concern here.

[baburdick]

It's actually exist? that you want to demonstrate historical support for, not exists? which is being removed. You're switching to exist?. So you want to demonstrate this switch is valid going back to some impressively old implementation, right? (e.g. https://github.com/ruby/ruby/blob/v1_9_0_0/file.c#L4445 and https://github.com/ruby/ruby/blob/v1_9_0_0/dir.c#L1906).

[baburdick]

What options do we have here for CI, so we can validate the test suite is sufficient and passes? GitHub Actions? CircleCI? Team City? Etc.?

[albertosaurus]

GitHub Actions is what everyone uses.

[maneyko]

Ah right. Thanks for catching that. I've updated the PR description with the correct references.