Setting up tree-sitter in Nvim

The grammar isn’t shipped with nvim-treesitter, so it has to be registered by hand. With the nvim-treesitter master branch:

vim.filetype.add({ extension = { m2 = "macaulay2" } }) -- not needed with m2.nvim

require("nvim-treesitter.parsers").get_parser_configs().macaulay2 = {
  install_info = {
    url = "https://github.com/AlexanderGolys/tree-sitter-macaulay2",
    files = { "src/parser.c", "src/scanner.c" },
  },
  filetype = "macaulay2",
}

Then install the parser:

:TSInstall macaulay2

Highlight queries live in the grammar repository’s queries/ directory and need to be on your runtimepath under queries/macaulay2/. The Nvim plugin ships folding, indentation and tags queries; with its parser option pointing at a local checkout of the grammar, it does the registration and the runtimepath part for you.