YouCompleteMe configuration for Qt5 projects

Here is a configuration file for the YouCompleteMe vim plugin that allows code completion for Qt5 projects. The file was shameless ripped off the News Blur Reader project.

The configuration is tested with YouCompleteMe's rev. 56e69412.

In order to locate Qt moc files this config assumes that your build directory is build. Also the sources are supposed to be located in the root and Tests directories. Change that as needed.

Save the file as in the root directory of your Qt project.

import os
import ycm_core
from clang_helpers import PrepareClangFlags

# 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:
# 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 = ''

# These are the compilation flags that will be used in case there's no
# compilation database set.
flags = [
# THIS IS IMPORTANT! Without a "-std=<something>" flag, clang won't know which
# language to use when compiling headers. So it will guess. Badly. So C++
# headers will be compiled as C headers. You don't want that so ALWAYS specify
# a "-std=<something>".
# For a C project, you would set this to something like 'c99' instead of
# '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++'.

'-I', '/usr/lib/qt/mkspecs/linux-clang',
'-I', '/usr/include/qt',
'-I', '/usr/include/qt/QtConcurrent',
'-I', '/usr/include/qt/QtCore',
'-I', '/usr/include/qt/QtDBus',
'-I', '/usr/include/qt/QtGui',
'-I', '/usr/include/qt/QtHelp',
'-I', '/usr/include/qt/QtMultimedia',
'-I', '/usr/include/qt/QtMultimediaWidgets',
'-I', '/usr/include/qt/QtNetwork',
'-I', '/usr/include/qt/QtOpenGL',
'-I', '/usr/include/qt/QtPlatformSupport',
'-I', '/usr/include/qt/QtPositioning',
'-I', '/usr/include/qt/QtScript',
'-I', '/usr/include/qt/QtScriptTools',
'-I', '/usr/include/qt/QtSql',
'-I', '/usr/include/qt/QtSvg',
'-I', '/usr/include/qt/QtTest',
'-I', '/usr/include/qt/QtUiTools',
'-I', '/usr/include/qt/QtV8',
'-I', '/usr/include/qt/QtWebKit',
'-I', '/usr/include/qt/QtWebKitWidgets',
'-I', '/usr/include/qt/QtWidgets',
'-I', '/usr/include/qt/QtXml',
'-I', '/usr/include/qt/QtXmlPatterns',

'-I', '.',
'-I', 'Tests',
'-I', 'build',
'-I', 'build/Tests'

if compilation_database_folder:
  database = ycm_core.CompilationDatabase( compilation_database_folder )
  database = None

def DirectoryOfThisScript():
  return os.path.dirname( os.path.abspath( __file__ ) )

def MakeRelativePathsInFlagsAbsolute( flags, working_directory ):
  if not working_directory:
    return 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

      if flag.startswith( path_flag ):
        path = flag[ len( path_flag ): ]
        new_flag = path_flag + os.path.join( working_directory, path )

    if new_flag:
      new_flags.append( new_flag )
  return new_flags

def FlagsForFile( filename ):
  if database:
    # Bear in mind that compilation_info.compiler_flags_ does NOT return a
    # python list, but a "list-like" StringVec object
    compilation_info = database.GetCompilationInfoForFile( filename )
    final_flags = PrepareClangFlags(
            compilation_info.compiler_working_dir_ ),
        filename )
    relative_to = DirectoryOfThisScript()
    final_flags = MakeRelativePathsInFlagsAbsolute( flags, relative_to )

  return {
    'flags': final_flags,
    'do_cache': True


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