dotfiles/config/nvim/nifoc/formatting.fnl

(let [mod {}
      b vim.b
      cmd vim.cmd
      api vim.api
      set-bufvar vim.api.nvim_buf_set_var]
  (fn mod.setup []
    (let [usercmd vim.api.nvim_create_user_command
          augroup (vim.api.nvim_create_augroup :NifocFormatting {:clear true})
          aucmd vim.api.nvim_create_autocmd]
      (usercmd :FormatDisableBuffer mod.disable-for-buffer
               {:desc "Disable Formatting for the current buffer"})
      (usercmd :FormatEnableBuffer mod.enable-for-buffer
               {:desc "Enable Formatting for the current buffer"})
      (aucmd :BufWritePre {:callback mod.maybe-format-buffer
                           :group augroup
                           :desc "Run Formatter"})))

  (fn run-neoformat [formatprg]
    (let [neoformat (.. "Neoformat " formatprg)
          cmdheight (vim.opt.cmdheight:get)]
      ;; Workaround for a prompt issue with cmdheight=0
      (set vim.opt.cmdheight 1)
      (cmd (.. "try | undojoin | " neoformat " | catch /E790/ | " neoformat
               " | endtry"))
      (set vim.opt.cmdheight cmdheight)))

  (fn mod.enable-for-buffer []
    (set-bufvar 0 :nifoc_formatter_disabled 0))

  (fn mod.disable-for-buffer []
    (set-bufvar 0 :nifoc_formatter_disabled 1))

  (fn mod.active? []
    (if (= b.nifoc_formatter_disabled 1) false
        (= b.nifoc_lsp_formatter_enabled 1) true
        (not= (vim.opt_local.formatprg:get) "") true
        false))

  (fn mod.maybe-enable-lsp [client bufnr]
    (when (client.supports_method :textDocument/rangeFormatting)
      (api.nvim_buf_set_option bufnr :formatexpr "v:lua.vim.lsp.formatexpr()"))
    (when (client.supports_method :textDocument/formatting)
      (set-bufvar bufnr :nifoc_lsp_formatter_enabled 1)))

  (fn mod.maybe-format-buffer []
    (let [formatprg (vim.opt_local.formatprg:get)
          formatprg-exe (-> formatprg (vim.split " " {:trimempty true}) (. 1))]
      (if (= b.nifoc_formatter_disabled 1) nil
          (= b.nifoc_lsp_formatter_enabled 1) (vim.lsp.buf.format {:timeout_ms 1000})
          (not= formatprg-exe nil) (run-neoformat formatprg-exe))))

  mod)