YCM: Support Objective-C and Objective-C++

tools/vim/chromium.ycm_extra_conf.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Autocompletion config for YouCompleteMe in Chromium.
 #
 # USAGE:
 #
 #   1. Install YCM [https://github.com/Valloric/YouCompleteMe]
 #          (Googlers should check out [go/ycm])
@@ skipping 45 matching lines @@
 import sys
 
 # Flags from YCM's default config.
 _default_flags = [
   '-DUSE_CLANG_COMPLETER',
   '-std=c++11',
   '-x',
   'c++',
 ]
 
+_extension_flags = {
+  '.m': ['-x', 'objective-c'],
+  '.mm': ['-x', 'objective-c++'],
+}
 
 def PathExists(*args):
   return os.path.exists(os.path.join(*args))
 
 
 def FindChromeSrcFromFilename(filename):
   """Searches for the root of the Chromium checkout.
 
   Simply checks parent directories until it finds .gclient and src/.
 
@@ skipping 265 matching lines @@
   """This is the main entry point for YCM. Its interface is fixed.
 
   Args:
     filename: (String) Path to source file being edited.
 
   Returns:
     (Dictionary)
       'flags': (List of Strings) Command line flags.
       'do_cache': (Boolean) True if the result should be cached.
   """
+  ext = os.path.splitext(filename)[1]
   abs_filename = os.path.abspath(filename)
   chrome_root = FindChromeSrcFromFilename(abs_filename)
   clang_flags = GetClangOptionsFromNinjaForFilename(chrome_root, abs_filename)
 
   # If clang_flags could not be determined, then assume that was due to a
   # transient failure. Preventing YCM from caching the flags allows us to try to
   # determine the flags again.
   should_cache_flags_for_file = bool(clang_flags)
 
-  final_flags = _default_flags + clang_flags
+  final_flags = _default_flags + _extension_flags.get(ext, []) + clang_flags
 
   return {
     'flags': final_flags,
     'do_cache': should_cache_flags_for_file
   }