Hey there, Yuan Fu.

First of all: Thank you for the tremendous effort you've put in to get a tree-sitter implementation mainlined into Emacs. For some of the major-modes I've been working on, tree-sitter has been a godsend and if it can enable some of them to become mainlined into Emacs... I mean nothing could be better!

That said, I've noticed something when building the feature/tree-sitter branch, and also while testing other things tree-sitter related... If a language-definition SO is missing... treesit.el in Emacs only reports looking for files and folders typically found within $HOME/.emacs.d/ (that is user-owned files).

Based on that, I'm assuming those are the only locations probed. Is that assumption correct?

If so, I think that is going to become a problem quite quickly if/when Linux distro starts providing Emacs-builds with tree-sitter enabled. Before that can be done, there needs to be support put in place to load these from a system/distro/package-manager owned location, or else it's going to be near-impossible for distros to ship a working Emacs with tree-sitter.

Should we consider adding another system-wide location for such files? /usr/lib/emacs? /usr/share/emacs?

What do you guys think?