fix: impure formatting, lsp fallback not applied on load

doc/guard.nvim.txt

@@ -1,4 +1,4 @@
-*guard.nvim.txt*          For NVIM v0.8.0         Last change: 2024 October 25
+*guard.nvim.txt*          For NVIM v0.8.0         Last change: 2024 October 26
 
 ==============================================================================
 Table of Contents                               *guard.nvim-table-of-contents*

lua/guard/events.lua

@@ -60,6 +60,28 @@ function M.watch_ft(ft)
   })
 end
 
+---@param config table
+---@param ft string
+---@param buf number
+function M.maybe_default_to_lsp(config, ft, buf)
+  if config.formatter then
+    return
+  end
+  config:fmt('lsp')
+  if getopt('fmt_on_save') then
+    if
+      #api.nvim_get_autocmds({
+        group = M.group,
+        event = 'FileType',
+        pattern = ft,
+      }) == 0
+    then
+      M.watch_ft(ft)
+    end
+    M.try_attach_to_buf(buf)
+  end
+end
+
 function M.create_lspattach_autocmd()
   au('LspAttach', {
     group = M.group,
@@ -68,27 +90,15 @@ function M.create_lspattach_autocmd()
         return
       end
       local client = vim.lsp.get_client_by_id(args.data.client_id)
-      ---@diagnostic disable-next-line: need-check-nil
-      if not client.supports_method('textDocument/formatting') then
+      if
+        not client
+        or not client.supports_method('textDocument/formatting', { bufnr = args.data.buf })
+      then
         return
       end
       local ft_handler = require('guard.filetype')
       local ft = vim.bo[args.buf].filetype
-      if not (ft_handler[ft] and ft_handler[ft].formatter) then
-        ft_handler(ft):fmt('lsp')
-      end
-      if getopt('fmt_on_save') then
-        if
-          #api.nvim_get_autocmds({
-            group = M.group,
-            event = 'FileType',
-            pattern = ft,
-          }) == 0
-        then
-          M.watch_ft(ft)
-        end
-        M.try_attach_to_buf(args.buf)
-      end
+      M.maybe_default_to_lsp(ft_handler(ft), ft, args.buf)
     end,
   })
 end

lua/guard/format.lua

@@ -1,9 +1,7 @@
-local api = vim.api
 local spawn = require('guard.spawn')
 local util = require('guard.util')
-local report_error = util.report_error
 local filetype = require('guard.filetype')
-local iter, filter = vim.iter, vim.tbl_filter
+local api, iter, filter = vim.api, vim.iter, vim.tbl_filter
 
 local function save_views(bufnr)
   local views = {}
@@ -53,8 +51,9 @@ end
 local function do_fmt(buf)
   buf = buf or api.nvim_get_current_buf()
   local ft_conf = filetype[vim.bo[buf].filetype]
+
   if not ft_conf or not ft_conf.formatter then
-    report_error('missing config for filetype ' .. vim.bo[buf].filetype)
+    util.report_error('missing config for filetype ' .. vim.bo[buf].filetype)
     return
   end
 
@@ -81,7 +80,7 @@ local function do_fmt(buf)
   -- check if all cmds executable again, since user can call format manually
   local all_executable = not iter(fmt_configs):any(function(config)
     if config.cmd and vim.fn.executable(config.cmd) ~= 1 then
-      report_error(config.cmd .. ' not executable')
+      util.report_error(config.cmd .. ' not executable')
       return true
     end
     return false
@@ -101,8 +100,8 @@ local function do_fmt(buf)
 
   -- error if one of the formatters is impure and the user requested range formatting
   if range and #impure:totable() > 0 then
-    report_error('Cannot apply range formatting for filetype ' .. vim.bo[buf].filetype)
-    report_error(impure
+    util.report_error('Cannot apply range formatting for filetype ' .. vim.bo[buf].filetype)
+    util.report_error(impure
       :map(function(config)
         return config.cmd
       end)
@@ -214,7 +213,7 @@ local function do_fmt(buf)
     end
 
     -- refresh buffer
-    if impure and #impure > 0 then
+    if impure and #impure:totable() > 0 then
       vim.schedule(function()
         api.nvim_buf_call(buf, function()
           local views = save_views(buf)

plugin/guard.lua

@@ -6,6 +6,7 @@ loaded = true
 
 local api = vim.api
 local events = require('guard.events')
+local ft_handler = require('guard.filetype')
 
 local cmds = {
   fmt = function()
@@ -114,3 +115,16 @@ end, {
 })
 
 events.create_lspattach_autocmd()
+
+for _, buf in ipairs(api.nvim_list_bufs()) do
+  if api.nvim_buf_is_loaded(buf) then
+    if
+      vim.iter(vim.lsp.get_clients({ bufnr = buf })):any(function(c)
+        return c.supports_method('textDocument/formatting')
+      end)
+    then
+      local ft = vim.bo[buf].ft
+      events.maybe_default_to_lsp(ft_handler(ft), ft, buf)
+    end
+  end
+end