Upgrade issues - MacOS Ventura - command-t.vim could not load the C extension about command-t

[wincent]

Slightly confusing matters is the recent re-write in Lua (nice!), which seems to require neovim? In any case, I'm slightly lost.

Sort of. In Neovim, you get to use the new Lua implementation which is faster and has a better UI. But the Ruby code is still there and can be used as a fallback, so when you run Command-T in Vim, that's the code that will get executed. (You can see the logic for this in the main entry point.) Given that a lot of Neovim/Vim users install plugins by using a plugin manager that points at the HEAD of the main/master branch of a plugin, as a plugin author I really have no choice but to maintain backwards compatibility pretty much "forever".

" use our local version of ruby, not the system version
set rubydll=/opt/homebrew/Cellar/ruby/3.2.1/lib/libruby.3.2.dylib

I've never had to use a hack like that myself, so can't really comment on the robustness of it. My approach has always been to use the same version of Ruby to do the Command-T build as Vim is using, and then I leave Vim alone. I know it's not always possible, but I generally try to avoid messing with the Ruby install on the system (eg. by installing a newer version with a Ruby version manager) at all because it tends to bring a bunch of headaches.

I tried various incanatations that worked in years past i.e. make \ rake \ etc. in various command-t plugin subdirectories

I think this is going to be the key.

Vim Ruby version: 3.2.1-p31
Expected version: 2.6.10-p210

You've got to get these versions to match, somehow. Based on your description, I gather 3.2.1-p31 is coming from Homebrew. Does it stay that way if you remove that rubydll setting? If it does, can you get that version of Ruby to activate when you run make clean && ruby extconf.rb && make? I don't know whether that means setting your $PATH or using a Ruby version manager to make sure you get the same version printed when you run ruby --version.

If you did want to use Neovim, then you could use the Lua implementation and you could forget about building the Ruby extension.

[wincent]

Closing due to inactivity.