Auto merge of #2473 - wincent:no-lazy, r=Valloric

No lazy

# PR Prelude

- [x] I have read and understood YCM's [CONTRIBUTING][cont] document.
- [x] I have read and understood YCM's [CODE_OF_CONDUCT][code] document.
- [x] I have included tests for the changes in my PR. If not, I have included a
  rationale for why I haven't.
- [x] **I understand my PR may be closed if it becomes obvious I didn't
  actually perform all of these steps.**

# Why this change is necessary and useful

See prior version of this PR (https://github.com/Valloric/YouCompleteMe/pull/2454) for more discussion.

[cont]: https://github.com/Valloric/YouCompleteMe/blob/master/CONTRIBUTING.md
[code]: https://github.com/Valloric/YouCompleteMe/blob/master/CODE_OF_CONDUCT.md

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README.md

@@ -2882,6 +2882,19 @@ executable first in your PATH when the virtual environment is active then if
 you set `g:ycm_python_binary_path` to just `'python'` it will be found as the
 first Python and used to run [JediHTTP][].
 
+### I want to defer loading of YouCompleteMe until after Vim finishes booting
+
+In recent versions of Vim, you can install YCM in a folder under
+`~/.vim/pack/*/opt` and then load it once the user is idle via an autocommand:
+
+```viml
+augroup load_ycm
+  autocmd!
+  autocmd CursorHold, CursorHoldI * :packadd YouCompleteMe
+                                \ | autocmd! load_ycm
+augroup END
+```
+
 Contributor Code of Conduct
 ---------------------------
 

plugin/youcompleteme.vim

@@ -128,16 +128,7 @@ let g:ycm_goto_buffer_command =
 let g:ycm_disable_for_files_larger_than_kb =
       \ get( g:, 'ycm_disable_for_files_larger_than_kb', 1000 )
 
-" On-demand loading. Let's use the autoload folder and not slow down vim's
-" startup procedure.
-if has( 'vim_starting' ) " loading at startup
-  augroup youcompletemeStart
-    autocmd!
-    autocmd VimEnter * call youcompleteme#Enable()
-  augroup END
-else " manual loading with :packadd
 call youcompleteme#Enable()
-endif
 
 " This is basic vim plugin boilerplate
 call s:restore_cpo()