new_contents: import os
  import ycm_core
  
  # These are the compilation flags that will be used in case there's no
  # compilation database set (by default, one is not set).
  # CHANGE THIS LIST OF FLAGS. YES, THIS IS THE DROID YOU HAVE BEEN LOOKING FOR.
  flags = [
  '-Wall',
  '-std=c++11',
  # ...and the same thing goes for the magic -x option which specifies the
  # language that the files to be compiled are written in. This is mostly
  # relevant for c++ headers.
  # For a C project, you would set this to 'c' instead of 'c++'.
  '-x',
  'c++',
  '-isystem',
  '../BoostParts',
  '-isystem',
  # This path will only work on OS X, but extra paths that don't exist are not
  # harmful
  '/System/Library/Frameworks/Python.framework/Headers',
  '-isystem',
  '../llvm/include',
  '-isystem',
  '../llvm/tools/clang/include',
  '-I',
  '.',
  '-I',
  './ClangCompleter',
  '-isystem',
  './tests/gmock/gtest',
  '-isystem',
  './tests/gmock/gtest/include',
  '-isystem',
  './tests/gmock',
  '-isystem',
  './tests/gmock/include',
  '-isystem',
  '/usr/include',
  '-isystem',
  '/usr/local/include',
  '-isystem',
  '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1',
  '-isystem',
  '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include',
  ]
  
  
  # Set this to the absolute path to the folder (NOT the file!) containing the
  # compile_commands.json file to use that instead of 'flags'. See here for
  # more details: http://clang.llvm.org/docs/JSONCompilationDatabase.html
  #
  # You can get CMake to generate this file for you by adding:
  #   set( CMAKE_EXPORT_COMPILE_COMMANDS 1 )
  # to your CMakeLists.txt file.
  #
  # Most projects will NOT need to set this to anything; you can just change the
  # 'flags' list of compilation flags. Notice that YCM itself uses that approach.
  compilation_database_folder = ''
  
  if os.path.exists( compilation_database_folder ):
    database = ycm_core.CompilationDatabase( compilation_database_folder )
  else:
    database = None
  
  SOURCE_EXTENSIONS = [ '.cpp', '.cxx', '.cc', '.c', '.m', '.mm' ]
  
  def DirectoryOfThisScript():
    return os.path.dirname( os.path.abspath( __file__ ) )
  
  
  def MakeRelativePathsInFlagsAbsolute( flags, working_directory ):
    if not working_directory:
      return list( flags )
    new_flags = []
    make_next_absolute = False
    path_flags = [ '-isystem', '-I', '-iquote', '--sysroot=' ]
    for flag in flags:
      new_flag = flag
  
      if make_next_absolute:
        make_next_absolute = False
        if not flag.startswith( '/' ):
          new_flag = os.path.join( working_directory, flag )
  
      for path_flag in path_flags:
        if flag == path_flag:
          make_next_absolute = True
          break
  
        if flag.startswith( path_flag ):
          path = flag[ len( path_flag ): ]
          new_flag = path_flag + os.path.join( working_directory, path )
          break
  
      if new_flag:
        new_flags.append( new_flag )
    return new_flags
  
  
  def IsHeaderFile( filename ):
    extension = os.path.splitext( filename )[ 1 ]
    return extension in [ '.h', '.hxx', '.hpp', '.hh' ]
  
  
  def GetCompilationInfoForFile( filename ):
    # The compilation_commands.json file generated by CMake does not have entries
    # for header files. So we do our best by asking the db for flags for a
    # corresponding source file, if any. If one exists, the flags for that file
    # should be good enough.
    if IsHeaderFile( filename ):
      basename = os.path.splitext( filename )[ 0 ]
      for extension in SOURCE_EXTENSIONS:
        replacement_file = basename + extension
        if os.path.exists( replacement_file ):
          compilation_info = database.GetCompilationInfoForFile(
            replacement_file )
          if compilation_info.compiler_flags_:
            return compilation_info
      return None
    return database.GetCompilationInfoForFile( filename )
  
  
  def FlagsForFile( filename, **kwargs ):
    if database:
      # Bear in mind that compilation_info.compiler_flags_ does NOT return a
      # python list, but a "list-like" StringVec object
      compilation_info = GetCompilationInfoForFile( filename )
      if not compilation_info:
        return None
  
      final_flags = MakeRelativePathsInFlagsAbsolute(
        compilation_info.compiler_flags_,
        compilation_info.compiler_working_dir_ )
  
    else:
      relative_to = DirectoryOfThisScript()
      final_flags = MakeRelativePathsInFlagsAbsolute( flags, relative_to )
  
    return {
      'flags': final_flags,
      'do_cache': True
    }
  
  
subject: add YouCompleteMe configuration file