fix: only clear autocmd group if it was created

Fixes zbirenbaum#503

Author: AntoineGS

lua/copilot/client/init.lua

@@ -8,13 +8,14 @@ local client_config = require("copilot.client.config")
 local is_disabled = false
 
 ---@class CopilotClient
+---@field augroup string|nil
 ---@field id integer|nil
 ---@field capabilities lsp.ClientCapabilities | nil
 ---@field config vim.lsp.ClientConfig | nil
 ---@field startup_error string | nil
 ---@field initialized boolean
 local M = {
-  augroup = "copilot.client",
+  augroup = nil,
   id = nil,
   capabilities = nil,
   config = nil,
@@ -150,7 +151,11 @@ function M.setup()
   is_disabled = false
 
   M.id = nil
-  vim.api.nvim_create_augroup(M.augroup, { clear = true })
+
+  -- nvim_clear_autocmds throws an error if the group does not exist
+  local augroup = "copilot.client"
+  vim.api.nvim_create_augroup(augroup, { clear = true })
+  M.augroup = augroup
 
   vim.api.nvim_create_autocmd("FileType", {
     group = M.augroup,
@@ -165,7 +170,10 @@ end
 function M.teardown()
   is_disabled = true
 
-  vim.api.nvim_clear_autocmds({ group = M.augroup })
+  -- nvim_clear_autocmds throws an error if the group does not exist
+  if M.augroup then
+    vim.api.nvim_clear_autocmds({ group = M.augroup })
+  end
 
   if M.id then
     vim.lsp.stop_client(M.id)