Neovim support

The repository includes a runtime plugin in editors/nvim. It detects *.plenty files, highlights source syntax using the active colorscheme, sets four-space soft tabs, supplies # comment formatting, and configures the language server for Neovim’s built-in LSP client.

Add this to init.lua, replacing the path with your Plenty checkout:

vim.opt.runtimepath:prepend('/absolute/path/to/plenty/editors/nvim')
vim.cmd('filetype plugin on')
vim.cmd('syntax enable')

Restart Neovim and open examples/classes.plenty. Check :set filetype? if highlighting is missing; it should report plenty. The plugin directory’s README also describes native package installation and the headless test commands. Extension detection takes precedence over generic content detection, including for source beginning with comments. An already-open buffer can be corrected with :setlocal filetype=plenty after the runtime path is available.

Highlighting includes keywords, primitive and collection types, function declarations, annotations such as @copy, numbers and suffixes, strings, byte literals and escapes, operators, and comments. Single- and double-quoted strings stay on one line; triple-quoted strings span lines. See source syntax. Highlighting uses regular expressions and does not perform semantic checks. Reserved words can be colored even when their construct is not implemented.

Language server

With Neovim 0.11 or later, editors/nvim/lsp/plenty.lua configures the server. Enable it after the runtime path above:

vim.lsp.enable('plenty')
-- If `plenty` is not on PATH:
-- vim.lsp.config('plenty', { cmd = { '/path/to/plenty', 'lsp' } })

vim.api.nvim_create_autocmd('LspAttach', {
  callback = function(event)
    local client = vim.lsp.get_client_by_id(event.data.client_id)
    if not client or client.name ~= 'plenty' then
      return
    end
    vim.lsp.inlay_hint.enable(true, { bufnr = event.buf })
    vim.keymap.set('n', 'gd', vim.lsp.buf.definition, { buffer = event.buf })
    vim.lsp.completion.enable(true, client.id, event.buf, { autotrigger = true })
  end,
})

K shows the hover. gd goes to the definition, into a read-only copy of a std module when the definition is there; CTRL-] does the same through Neovim’s default LSP tag function. Errors appear as diagnostics; ]d and [d move between them. Completion triggers after . and with CTRL-X CTRL-O. With nvim-cmp instead of the built-in completion, leave out the vim.lsp.completion.enable line and add the nvim_lsp source.

Neovim 0.10 has no vim.lsp.config; start the server from a FileType autocommand instead:

vim.api.nvim_create_autocmd('FileType', {
  pattern = 'plenty',
  callback = function()
    vim.lsp.start({
      name = 'plenty',
      cmd = { 'plenty', 'lsp' },
      root_dir = vim.fs.root(0, { 'plenty.toml', '.git' }),
    })
  end,
})

Inferred type hints

The LspAttach example enables inferred types inline for Plenty buffers. Neovim 0.10 or later provides vim.lsp.inlay_hint.enable. With the 0.10 startup example, add the same LspAttach callback but omit the vim.lsp.completion.enable line (that completion API requires 0.11). To enable or disable hints in an already-attached buffer, run:

:lua vim.lsp.inlay_hint.enable(true, { bufnr = 0 })
:lua vim.lsp.inlay_hint.enable(false, { bufnr = 0 })

A binding such as count = 42 displays an inferred : i64 after count. These labels do not change the file. An explicit count: i64 = 42 has no redundant hint. If hints are missing, check :checkhealth vim.lsp for an attached Plenty server, ensure the server binary includes inlay-hint support, and resolve check errors. See the hint coverage and limits. No editor-wide setting is changed by the server.

Formatting, automatic block indentation, and Tree-sitter are not provided.