YouCompleteMe extra configuration file

.ycm_extra_conf.py

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"""YouCompleteMe extra configuation."""

from os import path
from platform import system
from subprocess import Popen, PIPE
import ycm_core  # pylint: disable=import-error

FLAGS = [
    '-Wall',
    '-Wextra',
    '-Wdocumentation',
    '-x',
    'c++',
    # Add your project specific flags here
    '-std=c++11',
    '-Iinclude',
]

BUILD_DIRECTORY = 'build'

if path.exists(BUILD_DIRECTORY):
    DATABASE = ycm_core.CompilationDatabase(BUILD_DIRECTORY)
else:
    DATABASE = None

SYSTEM_FLAGS = []
if system() == 'Linux':
    # Linux system include directories are not available in the include
    # completer on Linux, so we get them from clang if its installed.
    PROCESS = Popen(
        'echo | clang -v -E -x c++ -', stdout=PIPE, stderr=PIPE, shell=True)
    _, ERR = PROCESS.communicate(input='')
    if PROCESS.returncode == 0:
        START = False
        for line in ERR.splitlines():
            if line == '#include <...> search starts here:':
                START = True
                continue
            if line == 'End of search list.':
                break
            if START:
                if 'c++' in line:
                    SYSTEM_FLAGS += ['-isystem', path.abspath(line.strip())]


def make_include_paths_absolute(flags, working_directory):
    """Make relative flag paths absolute."""
    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 = 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):
                new_path = flag[len(path_flag):]
                new_flag = path_flag + path.join(working_directory, new_path)
                break
        if new_flag:
            new_flags.append(new_flag)
    return new_flags


def is_header_file(filename):
    """True if filename is a header, False otherwise."""
    extension = path.splitext(filename)[1]
    return extension in ['.h', '.hxx', '.hpp', '.hh']


def get_compilation_info_for_file(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 is_header_file(filename):
        basename = path.splitext(filename)[0]
        for extension in ['.cpp', '.cxx', '.cc', '.c', '.m', '.mm', '.h',
                          '.hpp', '.hh', '.hxx']:
            replacement_file = basename + extension
            if path.exists(replacement_file):
                compilation_info = DATABASE.GetCompilationInfoForFile(
                    replacement_file)
                if compilation_info.compiler_flags_:
                    return compilation_info
        return None
    return DATABASE.GetCompilationInfoForFile(filename)


# pylint: disable=invalid-name,unused-argument
def FlagsForFile(filename, **kwargs):
    """Return compilation flags for the file called filename."""
    if DATABASE and not is_header_file(filename):
        # Bear in mind that compilation_info.compiler_flags_ does NOT return a
        # python list, but a "list-like" StringVec object
        compilation_info = get_compilation_info_for_file(filename)
        if not compilation_info:
            return None
        final_flags = make_include_paths_absolute(
            compilation_info.compiler_flags_,
            compilation_info.compiler_working_dir_)
    else:
        relative_to = path.dirname(path.abspath(__file__))
        final_flags = make_include_paths_absolute(FLAGS, relative_to)
    return {'flags': final_flags + SYSTEM_FLAGS, 'do_cache': True}