fix: avoid overwrting user defined mapping

fix some stuff

fix

lua/completion.lua

@@ -110,6 +110,16 @@ local function hasConfirmedCompletion()
   end
 end
 
+-- make sure we didn't overwrite user defined mapping
+local function checkMapping(map, key)
+  for _, m in ipairs(map) do
+    if api.nvim_replace_termcodes(m.lhs, true, false, true) == api.nvim_replace_termcodes(key, true, false, true) then
+      print(api.nvim_replace_termcodes(m.lhs, true, false, true), vim.inspect(m))
+      return false
+    end
+  end
+  return true
+end
 ------------------------------------------------------------------------
 --                            autocommands                            --
 ------------------------------------------------------------------------
@@ -213,11 +223,18 @@ M.on_attach = function(option)
     api.nvim_command("autocmd InsertCharPre <buffer> lua require'completion'.on_InsertCharPre()")
     api.nvim_command("autocmd CompleteDone <buffer> lua require'completion'.on_CompleteDone()")
   api.nvim_command("augroup end")
-  if string.len(opt.get_option('confirm_key')) ~= 0 then
-    api.nvim_buf_set_keymap(0, 'i', opt.get_option('confirm_key'),
-      'pumvisible() ? complete_info()["selected"] != "-1" ? "\\<Plug>(completion_confirm_completion)" :'..
-      ' "\\<c-e>\\<CR>" : "\\<CR>"',
-      {silent=false, noremap=false, expr=true})
+  local confirm_key = opt.get_option('confirm_key')
+  if string.len(confirm_key) ~= 0 then
+    if checkMapping(api.nvim_buf_get_keymap(0, "i"), confirm_key) and 
+      (manager.checkGlobalMapping or checkMapping(api.nvim_get_keymap("i"), confirm_key)) then
+      manager.checkGlobalMapping = true
+      api.nvim_buf_set_keymap(0, 'i', confirm_key,
+        'pumvisible() ? complete_info()["selected"] != "-1" ? "\\<Plug>(completion_confirm_completion)" :'..
+        ' "\\<c-e>\\<CR>" : "\\<CR>"',
+        {silent=false, noremap=false, expr=true})
+    else
+      api.nvim_err_writeln("completion-nvim: mapping conflict, please consider changing g:completion_confirm_key")
+    end
   end
   -- overwrite vsnip_integ autocmd since we handle it on ourself in confirmCompletion
   if vim.fn.exists("#vsnip_integ") then

lua/completion/manager.lua

@@ -19,6 +19,7 @@ manager = {
   confirmedCompletion = false,  -- flag for manual confirmation of completion
   forceCompletion     = false,  -- flag for forced manual completion/source change
   chainIndex          = 1,      -- current index in loaded chain
+  checkGlobalMapping  = false   -- indication of global mapping is checked or not
 }
 
 -- reset manager