RFC: cmdline completion (#362)

* manual support dot-repeat

* cmdwin and terminal

* cmdline only

* Fix

* fix

* Improve

* Fix test

* Support macro

* disable cmdline for now

* Simplify

* fmt

* consume once

* Ignore = type

* cmdline

* fmt

* Improve

* update

* fmt

* Support incsearch

* fix

* Add api

* Avoid cmdline completion if the native_menu enabled

* fix for macro

* Improve

* fmt

* Insert-mode only by default

* Update

* avoid conflict

* Improve default mapping

* Fix

* fix

* similar to native

* Update

* Fix README.md

* Improve

* Use <afile>

plugin/cmp.lua

@@ -5,11 +5,12 @@ vim.g.loaded_cmp = true
 
 local api = require "cmp.utils.api"
 local misc = require('cmp.utils.misc')
+local config = require('cmp.config')
 local highlight = require('cmp.utils.highlight')
 
 -- TODO: https://github.com/neovim/neovim/pull/14661
 vim.cmd [[
-  augroup cmp
+  augroup ___cmp___
     autocmd!
     autocmd InsertEnter * lua require'cmp.utils.autocmd'.emit('InsertEnter')
     autocmd InsertLeave * lua require'cmp.utils.autocmd'.emit('InsertLeave')
@@ -18,9 +19,42 @@ vim.cmd [[
     autocmd CompleteChanged * lua require'cmp.utils.autocmd'.emit('CompleteChanged')
     autocmd CompleteDone * lua require'cmp.utils.autocmd'.emit('CompleteDone')
     autocmd ColorScheme * call v:lua.cmp.plugin.colorscheme()
+    autocmd CmdlineEnter * call v:lua.cmp.plugin.cmdline.enter()
+    autocmd CmdlineLeave * call v:lua.cmp.plugin.cmdline.leave()
   augroup END
 ]]
 
+misc.set(_G, { 'cmp', 'plugin', 'cmdline', 'enter' }, function()
+  if config.get().experimental.native_menu then
+    return
+  end
+  local cmdtype = vim.fn.expand('<afile>')
+  if cmdtype ~= '=' then
+    vim.cmd [[
+      augroup cmp-cmdline
+        autocmd!
+        autocmd CmdlineChanged * lua require'cmp.utils.autocmd'.emit('TextChanged')
+      augroup END
+    ]]
+    require('cmp.utils.autocmd').emit('InsertEnter')
+  end
+end)
+
+misc.set(_G, { 'cmp', 'plugin', 'cmdline', 'leave' }, function()
+  if config.get().experimental.native_menu then
+    return
+  end
+  local cmdtype = vim.fn.expand('<afile>')
+  if cmdtype ~= '=' then
+    vim.cmd [[
+      augroup cmp-cmdline
+        autocmd!
+      augroup END
+    ]]
+    require('cmp.utils.autocmd').emit('InsertLeave')
+  end
+end)
+
 misc.set(_G, { 'cmp', 'plugin', 'colorscheme' }, function()
   highlight.inherit('CmpItemAbbrDefault', 'Pmenu', {
     guibg = 'NONE',