首先插件需要安裝一些dependencies。包括build-essential单默，cmake抛猖，python-dev魏颓， python3-dev岭辣。在MacOS底下xcode-select --install 取代 Linux底下的‘sudo apt install build-essential’。python 和python 3之前安裝vim和macvim的時(shí)候其實(shí)已經(jīng)裝完了甸饱，缺少的只有cmake這個(gè)插件沦童。

brew install cmake

然后在 /.vimrc文件中加入

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py'}

帶特定語言支持的安裝方式，上面語句改為

C-family languages

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py --clang-completer'}

C# supportbrew install Mono

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py --cs-completer'}

Go support

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py --go-completer'}

Rust support: support brew install rust

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py --rust-completer'}

Java support: support brew cask install java8

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py --java-completer'}

全部安裝

Plug 'Valloric/YouCompleteMe',{'do':'python3 install.py --all'}

打開vim叹话，輸入

:PlugInstall

自動(dòng)安裝所有偷遗。

/.vimrc文件中 YouCompleteMe的常用設(shè)置, 配置來源 http://howiefh.github.io/2015/05/22/vim-install-youcompleteme-plugin/

set completeopt=longest,menu    "讓Vim的補(bǔ)全菜單行為與一般IDE一致(參考VimTip1228)
autocmd InsertLeave * if pumvisible() == 0|pclose|endif "離開插入模式后自動(dòng)關(guān)閉預(yù)覽窗口
inoremap <expr> <CR>       pumvisible() ? "\<C-y>" : "\<CR>"    "回車即選中當(dāng)前項(xiàng)
"上下左右鍵的行為 會顯示其他信息
inoremap <expr> <Down>     pumvisible() ? "\<C-n>" : "\<Down>"
inoremap <expr> <Up>       pumvisible() ? "\<C-p>" : "\<Up>"
inoremap <expr> <PageDown> pumvisible() ? "\<PageDown>\<C-p>\<C-n>" : "\<PageDown>"
inoremap <expr> <PageUp>   pumvisible() ? "\<PageUp>\<C-p>\<C-n>" : "\<PageUp>"
" 跳轉(zhuǎn)到定義處
nnoremap <leader>jd :YcmCompleter GoToDefinitionElseDeclaration<CR>
nnoremap <F6> :YcmForceCompileAndDiagnostics<CR>    "force recomile with syntastic
" nnoremap <leader>lo :lopen<CR>    "open locationlist
" nnoremap <leader>lc :lclose<CR>   "close locationlist
inoremap <leader><leader> <C-x><C-o>
let g:ycm_global_ycm_extra_conf = '~/.vim/.ycm_extra_conf.py'
" 不顯示開啟vim時(shí)檢查ycm_extra_conf文件的信息  
let g:ycm_confirm_extra_conf=0
" 開啟基于tag的補(bǔ)全，可以在這之后添加需要的標(biāo)簽路徑  
let g:ycm_collect_identifiers_from_tags_files=1
"注釋和字符串中的文字也會被收入補(bǔ)全
let g:ycm_collect_identifiers_from_comments_and_strings = 0
" 輸入第2個(gè)字符開始補(bǔ)全
let g:ycm_min_num_of_chars_for_completion=2
" 禁止緩存匹配項(xiàng),每次都重新生成匹配項(xiàng)
let g:ycm_cache_omnifunc=0
" 開啟語義補(bǔ)全
let g:ycm_seed_identifiers_with_syntax=1    
"在注釋輸入中也能補(bǔ)全
let g:ycm_complete_in_comments = 1
"在字符串輸入中也能補(bǔ)全
let g:ycm_complete_in_strings = 1
" 設(shè)置在下面幾種格式的文件上屏蔽ycm
let g:ycm_filetype_blacklist = {
      \ 'tagbar' : 1,
      \ 'nerdtree' : 1,
      \}
"youcompleteme  默認(rèn)tab  s-tab 和 ultisnips 沖突
let g:ycm_key_list_select_completion = ['<Down>']
let g:ycm_key_list_previous_completion = ['<Up>']
" 修改對C函數(shù)的補(bǔ)全快捷鍵渣刷，默認(rèn)是CTRL + space鹦肿，修改為ALT + ;
let g:ycm_key_invoke_completion = '<M-;>'
" SirVer/ultisnips 代碼片斷
" Trigger configuration. Do not use <tab> if you use https://github.com/Valloric/YouCompleteMe.
let g:UltiSnipsExpandTrigger="<tab>"
let g:UltiSnipsJumpForwardTrigger="<tab>"
let g:UltiSnipsJumpBackwardTrigger="<s-tab>"
let g:UltiSnipsListSnippets="<c-e>"
"定義存放代碼片段的文件夾，使用自定義和默認(rèn)的辅柴，將會的到全局箩溃，有沖突的會提示
let g:UltiSnipsSnippetDirectories=["plugged/vim-snippets/UltiSnips"]
" 參考https://github.com/Valloric/YouCompleteMe/issues/36#issuecomment-62941322
" 解決ultisnips和ycm tab沖突，如果不使用下面的辦法解決可以參考
" https://github.com/Valloric/YouCompleteMe/issues/36#issuecomment-63205056的配置
" begin
" let g:ycm_key_list_select_completion=['<C-n>', '<Down>']
" let g:ycm_key_list_previous_completion=['<C-p>', '<Up>']
" let g:UltiSnipsExpandTrigger="<Tab>"
" let g:UltiSnipsJumpForwardTrigger="<Tab>"                                           
" let g:UltiSnipsJumpBackwardTrigger="<S-Tab>"
" end
" UltiSnips completion function that tries to expand a snippet. If there's no
" snippet for expanding, it checks for completion window and if it's
" shown, selects first element. If there's no completion window it tries to
" jump to next placeholder. If there's no placeholder it just returns TAB key 
function! g:UltiSnips_Complete()
    call UltiSnips#ExpandSnippet()
    if g:ulti_expand_res == 0
        if pumvisible()
            return "\<C-n>"
        else
            call UltiSnips#JumpForwards()
            if g:ulti_jump_forwards_res == 0
               return "\<TAB>"
            endif
        endif
    endif
    return ""
endfunction
au BufEnter * exec "inoremap <silent> " . g:UltiSnipsExpandTrigger . " <C-R>=g:UltiSnips_Complete()<cr>"
" Expand snippet or return
let g:ulti_expand_res = 1
function! Ulti_ExpandOrEnter()
    call UltiSnips#ExpandSnippet()
    if g:ulti_expand_res
        return ''
    else
        return "\<return>"
endfunction
" Set <space> as primary trigger
inoremap <return> <C-R>=Ulti_ExpandOrEnter()<CR>

~/.vim/.ycm_extra_conf.py文件示范

import os
import os.path
import fnmatch
import logging
import ycm_core
import re

BASE_FLAGS = [
        '-Wall',
        '-Wextra',
        '-Werror',
        '-Wno-long-long',
        '-Wno-variadic-macros',
        '-fexceptions',
        '-ferror-limit=10000',
        '-DNDEBUG',
        '-std=c++11',
        '-xc++',
        '-I/usr/lib/',
        '-I/usr/include/'
        ]

SOURCE_EXTENSIONS = [
        '.cpp',
        '.cxx',
        '.cc',
        '.c',
        '.m',
        '.mm'
        ]

SOURCE_DIRECTORIES = [
        'src',
        'lib'
        ]

HEADER_EXTENSIONS = [
        '.h',
        '.hxx',
        '.hpp',
        '.hh'
        ]

HEADER_DIRECTORIES = [
        'include'
        ]

def IsHeaderFile(filename):
    extension = os.path.splitext(filename)[1]
    return extension in HEADER_EXTENSIONS

def GetCompilationInfoForFile(database, filename):
    if IsHeaderFile(filename):
        basename = os.path.splitext(filename)[0]
        for extension in SOURCE_EXTENSIONS:
            # Get info from the source files by replacing the extension.
            replacement_file = basename + extension
            if os.path.exists(replacement_file):
                compilation_info = database.GetCompilationInfoForFile(replacement_file)
                if compilation_info.compiler_flags_:
                    return compilation_info
            # If that wasn't successful, try replacing possible header directory with possible source directories.
            for header_dir in HEADER_DIRECTORIES:
                for source_dir in SOURCE_DIRECTORIES:
                    src_file = replacement_file.replace(header_dir, source_dir)
                    if os.path.exists(src_file):
                        compilation_info = database.GetCompilationInfoForFile(src_file)
                        if compilation_info.compiler_flags_:
                            return compilation_info
        return None
    return database.GetCompilationInfoForFile(filename)

def FindNearest(path, target, build_folder):
    candidate = os.path.join(path, target)
    if(os.path.isfile(candidate) or os.path.isdir(candidate)):
        logging.info("Found nearest " + target + " at " + candidate)
        return candidate;

    parent = os.path.dirname(os.path.abspath(path));
    if(parent == path):
        raise RuntimeError("Could not find " + target);

    if(build_folder):
        candidate = os.path.join(parent, build_folder, target)
        if(os.path.isfile(candidate) or os.path.isdir(candidate)):
            logging.info("Found nearest " + target + " in build folder at " + candidate)
            return candidate;

    return FindNearest(parent, target, build_folder)

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 FlagsForClangComplete(root):
    try:
        clang_complete_path = FindNearest(root, '.clang_complete')
        clang_complete_flags = open(clang_complete_path, 'r').read().splitlines()
        return clang_complete_flags
    except:
        return None

def FlagsForInclude(root):
    try:
        include_path = FindNearest(root, 'include')
        flags = []
        for dirroot, dirnames, filenames in os.walk(include_path):
            for dir_path in dirnames:
                real_path = os.path.join(dirroot, dir_path)
                flags = flags + ["-I" + real_path]
        return flags
    except:
        return None

def FlagsForCompilationDatabase(root, filename):
    try:
        # Last argument of next function is the name of the build folder for
        # out of source projects
        compilation_db_path = FindNearest(root, 'compile_commands.json', 'build')
        compilation_db_dir = os.path.dirname(compilation_db_path)
        logging.info("Set compilation database directory to " + compilation_db_dir)
        compilation_db =  ycm_core.CompilationDatabase(compilation_db_dir)
        if not compilation_db:
            logging.info("Compilation database file found but unable to load")
            return None
        compilation_info = GetCompilationInfoForFile(compilation_db, filename)
        if not compilation_info:
            logging.info("No compilation info for " + filename + " in compilation database")
            return None
        return MakeRelativePathsInFlagsAbsolute(
                compilation_info.compiler_flags_,
                compilation_info.compiler_working_dir_)
    except:
        return None

def FlagsForFile(filename):
    root = os.path.realpath(filename);
    compilation_db_flags = FlagsForCompilationDatabase(root, filename)
    if compilation_db_flags:
        final_flags = compilation_db_flags
    else:
        final_flags = BASE_FLAGS
        clang_flags = FlagsForClangComplete(root)
        if clang_flags:
            final_flags = final_flags + clang_flags
        include_flags = FlagsForInclude(root)
        if include_flags:
            final_flags = final_flags + include_flags
    return {
            'flags': final_flags,
            'do_cache': True
            }