vim: Bump up neovim requirement to 0.7.0 or higher (#36)

Core lua plugins like lsp, treesitter, telescope, etc. require
neovim 0.7.0 or higher. Neovim 0.5.x or 0.6.x can still run minimally
with this and after versions of dotfiles, but most of lua-based
plugins will be disabled.

nvim/lua/config/lsp.lua

@@ -3,6 +3,10 @@
 -------------
 -- See ~/.dotfiles/vim/plugins.vim for the Plug directives
 
+if not pcall(require, 'lspconfig') then
+  print("Warning: lspconfig not available, skipping configuration.")
+  return
+end
 local lspconfig = require('lspconfig')
 
 -- lsp_signature

nvim/lua/config/statusline.lua

@@ -1,5 +1,9 @@
 -- Statusline config: lualine.nvim
 
+if not pcall(require, 'lualine') then
+  print("Warning: lualine not available, skipping configuration.")
+  return
+end
 
 -- From nvim-lualine/lualine.nvim/wiki/Component-snippets
 --- @param trunc_width number trunctates component when screen width is less then trunc_width

nvim/lua/config/telescope.lua

@@ -3,6 +3,11 @@
 ---------------
 -- @see  :help telescope.setup
 -- @see  https://github.com/nvim-telescope/telescope.nvim#telescope-setup-structure
+--
+if not pcall(require, 'telescope') then
+  print("Warning: telescope not available, skipping configuration.")
+  return
+end
 local telescope = require("telescope")
 
 if not pcall(require, 'telescope.actions.layout') then

nvim/lua/config/treesitter.lua

@@ -2,6 +2,7 @@
 -- https://github.com/nvim-treesitter/nvim-treesitter
 
 if not pcall(require, 'nvim-treesitter') then
+  print("Warning: treesitter not available, skipping configuration.")
   return
 end
 

vim/plugins.vim

@@ -95,7 +95,7 @@ if has('nvim-0.5.0')
 else
   Plug 'airblade/vim-gitgutter'
 endif
-if has('nvim-0.5.0')
+if has('nvim-0.7.0')
   Plug 'sindrets/diffview.nvim'
 endif
 if has('nvim-0.4.0') && exists('*nvim_open_win')
@@ -175,10 +175,12 @@ if has('nvim-0.5.0')
   Plug 'nvim-neo-tree/neo-tree.nvim', {'branch': 'main'}
   Plug 'MunifTanjim/nui.nvim'
   Plug 'nvim-lua/plenary.nvim'
-  Plug 'nvim-telescope/telescope.nvim', PinIf(!has('nvim-0.6.0'), {'commit': '80cdb00'})
+endif
+if has('nvim-0.7.0')
+  Plug 'nvim-telescope/telescope.nvim'
 endif
 
-if has('nvim-0.6.1')
+if has('nvim-0.7.0')
   " Treesitter (see ~/.config/nvim/lua/config/treesitter.lua)
   function! TSUpdate(arg) abort
     if luaeval('pcall(require, "nvim-treesitter")')
@@ -208,12 +210,12 @@ endif
 " Syntax, Completion, Language Servers, etc.
 " ------------------------------------------
 
-let g:dotfiles_completion_backend = has('nvim-0.5.0') ? '@lsp' : ''
+let g:dotfiles_completion_backend = has('nvim-0.7.0') ? '@lsp' : ''
 
 " 1. [Neovim 0.5.0 LSP]
 " See also for more config: ~/.config/nvim/lua/config/lsp.lua
 if g:dotfiles_completion_backend == '@lsp'
-  Plug 'neovim/nvim-lspconfig', PinIf(!has('nvim-0.7'), {'tag': 'v0.1.3'})
+  Plug 'neovim/nvim-lspconfig'
   Plug 'williamboman/nvim-lsp-installer'
   Plug 'folke/lua-dev.nvim'
 

vim/vimrc

@@ -16,9 +16,15 @@ endif
 
 " Check neovim version.
 if has('nvim') && !has('nvim-0.7.0')
-  let s:warning_msg = 'Please upgrade to latest neovim (0.7.0+). Support for neovim <= 0.6 will be dropped soon. '
-  let s:install_command_hint = printf('(Try: %s install neovim)', has('mac') ? 'brew' : 'dotfiles')
-  autocmd VimEnter * echohl WarningMsg | echom s:warning_msg . s:install_command_hint | echohl None
+  let s:warning_msg = 'Please upgrade to latest neovim (0.7.0+). Support for neovim < 0.7 will be dropped soon. '
+  let s:warning_msg .= printf('(Try: %s install neovim)', has('mac') ? 'brew' : 'dotfiles')
+  if exists('*luaeval')
+    autocmd VimEnter * call timer_start(100, { ->
+          \ luaeval("vim.notify(_A[1], _A[2], _A[3])", [s:warning_msg, 'error', {'title': 'Deprecation Warning'}])
+          \ })
+  else
+    autocmd VimEnter * echohl WarningMsg | echom s:warning_msg | echohl None
+  endif
 endif
 
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