copilot.lua + neovim 0.10.2 raise an error when completing line with CJK characters

[wrvsrx]

Reproduce

1. Install copilot.lua with neovim 0.10.2 and setup it using following config (I use lazy.nvim to load it)

           {
               dir = "/nix/store/rwcag86gmdas1n3y0vz9wgc9alrhs5ia-lazy-plugins/copilot.lua",
               event = "VeryLazy",
               opts = {
                   copilot_node_command = "node",
                   filetypes = {
                       ["."] = false,
                       gitcommit = true,
                       gitrebase = true,
                       help = false,
                       markdown = true,
                       yaml = true,
                   },
                   panel = {
                       auto_refresh = true,
                       enabled = true,
                       keymap = { accept = "<CR>", jump_next = "]]", jump_prev = "[[", open = "<C-CR>", refresh = "gr" },
                       layout = { position = "bottom", ratio = 0.4 },
                   },
                   suggestion = {
                       auto_trigger = true,
                       debounce = 75,
                       enabled = true,
                       keymap = {
                           accept = "<c-c>a",
                           accept_line = "<c-c>l",
                           accept_word = "<c-c>w",
                           dismiss = "<c-c>d",
                           next = "<c-c>n",
                           prev = "<c-c>p",
                       },
                   },
               },
           },

2. Create a file with CJK character and complete the line with CJK character using keymap (<c-c>a)

   #include <iostream>
   
   auto main() -> int {
     // 中|
     std::cout << "Hello, World!" << std::endl;
   }

   | is the cursor position

3. copilot.lua raises an error

   

Debug

I notice the problem is caused by this PR, I revert the in my fork and the error disappears. I don't understand the detail and hope this problem can be fixed on copilot.lua side.

[wrvsrx]

The error disappears on neovim nightly. I think it might be a problem on neovim side.

[wrvsrx]

This error is fixed in this PR