Use nvim-notify for showing messages

autoload/buf_utils.vim

@@ -11,7 +11,11 @@ function! buf_utils#GoToBuffer(count, direction) abort
   endif
   " Check the validity of buffer number.
   if index(s:GetBufNums(), a:count) == -1
-    call utils#Log('Invalid bufnr: ' . a:count, 'error')
+    " Using `lua vim.notify('invalid bufnr: ' .. a:count)` won't work, because
+    " we are essentially mixing Lua and vim script. We need to make sure that
+    " args inside vim.notify() are valid vim values. The conversion from vim
+    " value to lua value will be done by Nvim. See also https://github.com/neovim/neovim/pull/11338.
+    call v:lua.vim.notify('Invalid bufnr: ' . a:count, 'error', {'title': 'nvim-config'})
     return
   endif
 

autoload/utils.vim

@@ -145,25 +145,3 @@ function! utils#Get_titlestr() abort
 
   return l:title_str
 endfunction
-
-" Log a message using certain highlight group
-function! utils#Log(msg, ...) abort
-  let l:hi = ''
-  if len(a:000) == 1
-    if a:1 ==? 'info'
-      let l:hi = 'Normal'
-    elseif a:1 ==? 'warning'
-      let l:hi = 'WarningMsg'
-    elseif a:1 ==? 'error'
-      let l:hi = 'ErrorMsg'
-    else
-      echoerr 'Unsupported log level:' a:1
-    endif
-  else
-    let l:hi = 'Normal'
-  endif
-
-  execute 'echohl' l:hi
-  unsilent echomsg a:msg
-  echohl None
-endfunction

core/autocommands.vim

@@ -32,7 +32,8 @@ augroup END
 " https://github.com/vim/vim/issues/4379
 augroup non_utf8_file_warn
   autocmd!
-  autocmd BufRead * if &fileencoding != 'utf-8' | unsilent echomsg 'File not in UTF-8 format!' | endif
+  " we can not `lua vim.notify()`: it will error out E5107 parsing lua.
+  autocmd BufRead * if &fileencoding != 'utf-8' | call v:lua.vim.notify('File not in UTF-8 format!', 'warn', {'title': 'nvim-config'}) | endif
 augroup END
 
 " Automatically reload the file if it is changed outside of Nvim, see
@@ -42,7 +43,7 @@ augroup END
 " https://vi.stackexchange.com/a/20397/15292.
 augroup auto_read
   autocmd!
-  autocmd FileChangedShellPost * call utils#Log("File changed on disk. Buffer reloaded!", 'warning')
+  autocmd FileChangedShellPost * call v:lua.vim.notify("File changed on disk. Buffer reloaded!", 'warn', {'title': 'nvim-config'})
   autocmd FocusGained,CursorHold * if getcmdwintype() == '' | checktime | endif
 augroup END
 

core/mappings.vim

@@ -102,7 +102,7 @@ inoremap <expr> <s-tab> pumvisible() ? "\<c-p>" : "\<s-tab>"
 " Edit and reload init.vim quickly
 nnoremap <silent> <leader>ev :<C-U>tabnew $MYVIMRC <bar> tcd %:h<cr>
 nnoremap <silent> <leader>sv :<C-U>silent update $MYVIMRC <bar> source $MYVIMRC <bar>
-      \ echomsg "Nvim config successfully reloaded!"<cr>
+      \ call v:lua.vim.notify("Nvim config successfully reloaded!", 'info', {'title': 'nvim-config'})<cr>
 
 " Reselect the text that has just been pasted, see also https://stackoverflow.com/a/4317090/6064933.
 nnoremap <expr> <leader>v printf('`[%s`]', getregtype()[0])

core/ui.vim

@@ -64,7 +64,7 @@ let s:colorscheme_func = printf('s:my_theme_dict.%s()', s:theme)
 if has_key(s:my_theme_dict, s:theme)
   execute 'call ' . s:colorscheme_func
 else
-  call utils#Log('Invalid colorscheme function: ' . s:colorscheme_func, 'error')
+  call v:lua.vim.notify('Invalid colorscheme function: ' . s:colorscheme_func, 'error', {'title': 'nvim-config'})
 endif
 "}}
 "}

lua/plugins.lua

@@ -95,6 +95,7 @@ require('packer').startup(
     use 'sainnhe/gruvbox-material'
     use 'shaunsingh/nord.nvim'
     use 'NTBBloodbath/doom-one.nvim'
+
     -- colorful status line and theme
     use 'vim-airline/vim-airline-themes'
     use 'vim-airline/vim-airline'
@@ -106,6 +107,9 @@ require('packer').startup(
     -- Highlight URLs inside vim
     use 'itchyny/vim-highlighturl'
 
+    -- notification plugin
+    use {'rcarriga/nvim-notify', config = 'vim.notify = require("notify")'}
+
     -- For Windows and Mac, we can open an URL in the browser. For Linux, it may
     -- not be possible since we maybe in a server which disables GUI.
     if (vim.g.is_win == 1) or (vim.g.is_mac == 1) then