Add NvChadUpdate command and shortcut for it

map leader+uu to it

summary of what it does:

first ask the user for confirmation and tell that the updater is gonna run git reset --hard in config repo and chadrc will be restored

take backup of chadrc in a lua string and locally in a file with chadrc.bak.(random numbers)

git reset on config dir and git pull

whether success or error, restore the chadrc file

if restore fails, then print backup file path

for more deep understanding, read the comments in utils.lua

lua/chadrc.lua

@@ -141,6 +141,7 @@ M.mappings = {
       copywhole_file = "<C-a>",
       toggle_linenr = "<leader>n", -- show or hide line number
       theme_toggle = "<leader>x",
+      update_nvchad = "<leader>uu",
    },
 }
 

lua/default_config.lua

@@ -140,6 +140,7 @@ M.mappings = {
       copywhole_file = "<C-a>",
       toggle_linenr = "<leader>n", -- show or hide line number
       theme_toggle = "<leader>x",
+      update_nvchad = "<leader>uu",
    },
 }
 

lua/mappings.lua

@@ -92,6 +92,10 @@ M.misc = function()
    cmd "silent! command PackerStatus lua require 'pluginList' require('packer').status()"
    cmd "silent! command PackerSync lua require 'pluginList' require('packer').sync()"
    cmd "silent! command PackerUpdate lua require 'pluginList' require('packer').update()"
+
+   -- add NvChadUpdate command and mapping
+   cmd "silent! command! NvChadUpdate lua require('utils').update_nvchad()"
+   map("n", user_map.misc.update_nvchad, ":NvChadUpdate<CR>", opt)
 end
 
 M.bufferline = function()

lua/utils.lua

@@ -148,6 +148,16 @@ M.close_buffer = function(bufexpr, force)
    end
 end
 
+-- wrapper to use vim.api.nvim_echo
+-- 1st arg - text - required
+-- 2nd arg - highlight group - if not present then use None
+M.echo = function(text, group)
+   if text == nil then
+      return
+   end
+   vim.api.nvim_echo({ { text, group or "None" } }, false, {})
+end
+
 -- 1st arg - r or w
 -- 2nd arg - file path
 -- 3rd arg - content if 1st arg is w
@@ -399,4 +409,75 @@ M.toggle_theme = function(themes)
    end
 end
 
+-- update nvchad
+M.update_nvchad = function()
+   -- in all the comments below, config means user config
+   local config_path = vim.fn.stdpath "config"
+   local config_name = vim.g.nvchad_user_config or "chadrc"
+   local config_file = config_path .. "/lua/" .. config_name .. ".lua"
+   -- generate a random file name
+   local config_file_backup = config_path .. "/" .. config_name .. ".lua.bak." .. math.random()
+   local utils = require "utils"
+   local echo = utils.echo
+
+   -- ask the user for confirmation to update because we are going to run git reset --hard
+   echo(
+      "Updater will run git reset --hard in config folder, so changes to existing repo files except "
+         .. config_name
+         .. " will be lost!\nUpdate NvChad ? [y/N]",
+      "WarningMsg"
+   )
+   local ans = string.lower(vim.fn.input "-> ") == "y"
+   utils.clear_cmdline()
+   if not ans then
+      echo("Update cancelled!", "Title")
+      return
+   end
+
+   -- first try to fetch contents of config, this will make sure it is readable and taking backup of its contents
+   local config_contents = utils.file("r", config_file)
+   -- also make a local backup in ~/.config/nvim, will be removed when config is succesfully restored
+   utils.file("w", config_file_backup, config_contents)
+   -- write original config file with its contents, will make sure charc is writable, this maybe overkill but a little precaution always helps
+   utils.file("w", config_file, config_contents)
+
+   -- function that will executed when git commands are done
+   local function update_exit(_, code)
+      -- restore config file irrespective of whether git commands were succesfull or not
+      if pcall(function()
+         utils.file("w", config_file, config_contents)
+      end) then
+         -- config restored succesfully, remove backup file that was created
+         if not pcall(os.remove, config_file_backup) then
+            echo("Warning: Failed to remove backup chadrc, remove manually.", "WarningMsg")
+            echo("Path: " .. config_file_backup, "WarningMsg")
+         end
+      else
+         echo("Error: Restoring " .. config_name .. " failed.\n", "ErrorMsg")
+         echo("Backed up " .. config_name .. " path: " .. config_file_backup .. "\n\n", "None")
+      end
+
+      -- close the terminal buffer only if update was success, as in case of error, we need the error message
+      if code == 0 then
+         vim.cmd "bd!"
+         echo("NvChad succesfully updated.\n", "String")
+      else
+         echo("Error: NvChad Update failed.\n", "ErrorMsg")
+      end
+   end
+
+   -- git commands that will executed, reset in case config was modfied
+   -- use --ff-only to not mess up if the local repo is outdated
+   local update_script = [[git reset --hard && git pull --set-upstream https://github.com/NvChad/NvChad main --ff-only]]
+
+   -- open a new buffer
+   vim.cmd "new"
+   -- finally open the pseudo terminal buffer
+   vim.fn.termopen(update_script, {
+      -- change dir to config path so we don't need to move in script
+      cwd = config_path,
+      on_exit = update_exit,
+   })
+end
+
 return M