(转）Vim自动补全神器：YouCompleteMe

时间 2019-11-13

原文原文链接

原文出处：http://blog.jobbole.com/58978/javascript

第一次据说这个插件仍是在偶然的状况下看到别人的博客，据说了这个插件的大名。原本打算在实训期间来完成安装的，无奈网实在不给力，也就拖到了回家的时候。在开始准备工做的时候就了解到这个插件不是很容易安装，安装的时候果真名不虚传。(关于这方面的内容，请查看另外一篇文章)不过，有付出总有回报，安装以后用上这个插件，真心为这个插件的强大所折服。php

那这个插件有何不一样？html

YouCompleteMe的特别之处

基于语义补全

总所周知，Vim是一款文本编辑器。也就是说，其最基础的工做就是编辑文本，而无论该文本的内容是什么。在Vim被程序员所使用后，其慢慢的被肩负了与IDE同样的工做，文本自动补全(ie.acp,omnicppcompleter)，代码检查(Syntastic)等等工做。java

针对文本自动补全这个功能来讲，主要有两种实现方式。python

基于文本

咱们经常使用的omnicppcompleter,acp,vim自带的c-x, c-n的实现方式就是基于文本。更通俗的说法，其实就是一个字：c++

猜

其经过文本进行一些正则表达式的匹配，再根据生成的tags(利用ctags生成)来实现自动补全的效果。git

基于语义

顾名思义，其是经过分析源文件，通过语法分析之后进行补全。因为对源文件进行分析，基于语义的补全能够作到很精确。可是这显然是vim所不可能支持的。并且通过这么多年发展，因为语法分析有很高的难度，也一直没有合适的工具出现。直到，由apple支持的clang/llvm横空出世。YouCompleteMe也正是在clang/llvm的基础上进行构建的。程序员

整合实现了多种插件

clang_complete
AutoComplPop
Supertab
neocomplcache
Syntastic(相似功能,仅仅针对c/c++/obj-c代码)

支持语言

c
c++
obj-c
c#
python

对于其余的语言，会调用vim设置的omnifunc来匹配，所以一样支持php,ruby等语言。github

已知的有 * javascript —-tern_for_vim * ruby/java —-eclimweb

使用效果图

使用感觉

和IDE同样，自动补全，
根据include的文件进行补全
不用再蹩脚的生成tags
补全很是精准，并且速度很快，不会有延迟(之前在大项目上，acp用起来实在是很卡)
支持相似tags的跳转，跳到定义处以及使用处
出错提示很智能，而且用起来真的是如丝般柔滑，不用输入:w进行强制检测

安装

说完了那么多好处，就要说到安装了。不一样于以往其余vim插件，YCM是一款编译型的插件。在下载完后，须要手动编译后才能使用。对应其余的插件来讲，仅仅就是把.vim的文件丢到相应文件夹下就能够。而这也加大了使用YCM的难度。

安装准备

最新版的Vim(7.3.584+)，编译时添加+python标志(已经安装的能够经过vim --version查看)
cmake(mac能够经过homebrew安装，brew install cmake,ubuntu能够经过sudo apt-get install cmake)
安装vundle插件，用于安装管理vim的插件

mac下快速安装

在.vimrc中添加下列代码

Bundle 'Valloric/YouCompleteMe'

1	Bundle 'Valloric/YouCompleteMe'

保存退出后打开vim，在正常模式下输入

:BundleInstall

1	:BundleInstall

等待vundle将YouCompleteMe安装完成

然后进行编译安装：

cd ~/.vim/bundle/YouCompleteMe
./install --clang-completer

1 2	cd ~/.vim/bundle/YouCompleteMe ./install --clang-completer

若是不须要c-family的补全，能够去掉--clang-completer。若是须要c#的补全，请加上--omnisharp-completer。

正常来讲,YCM会去下载clang的包，若是已经有，也能够用系统--system-libclang。

就这样，安装结束。打开vim，若是没有提示YCM未编译，则说明安装已经成功了。

手动编译安装

安装的脚本并非何时都好用，至少对我来讲是这样的。安装完以后出现了问题，参考issue#809。

在用:BundleInstall安装完成或者使用

git clone --recursive https://github.com/Valloric/YouCompleteMe.git

1	git clone --recursive https://github.com/Valloric/YouCompleteMe.git

获取最新的仓库，然后使用git submodule update --init --recursive确认仓库的完整性后，开始安装流程。

下载最新的clang二进制文件 YCM要求clang版本 > 3.2，通常来讲都是下载最新的。
安装python-dev.(ubuntu下使用sudo apt-get install python-dev,mac下默认提供，不然请安装command line tools)

编译

cd ~
mkdir ycm_build
cd ycm_build
cmake -G “Unix Makefiles” -DPATH_TO_LLVM_ROOT=~/ycm_temp/llvm_root_dir . ~/.vim/bundle/YouCompleteMe/cpp make ycm_support_libs

cd ~

mkdir ycm_build

cd ycm_build

cmake -G “Unix Makefiles” -DPATH_TO_LLVM_ROOT=~/ycm_temp/llvm_root_dir . ~/.vim/bundle/YouCompleteMe/cpp make ycm_support_libs

这里须要注意的是，~/ycm_temp/llvm_root_dir中包含的是根据第一步下载的压缩包解压出来的内容(包括include, bin等等文件)。

这样就完成了,开始感觉YCM提供的彻底不逊色于大型IDE所提供的自动补全功能吧。

配置

不一样于不少vim插件，YCM首先须要编译，另外还须要有配置。在vim启动后，YCM会找寻当前路径以及上层路径的.ycm_extra_conf.py.在~/.vim/bundle/YouCompleteMe/cpp/ycm/.ycm_extra_conf.py中提供了默认的模板。也能够参考个人(就在模板上改改而已)。不过这个解决了标准库提示找不到的问题。

通常来讲,我会在~目录下放一个默认的模板，然后再根据不一样的项目在当前目录下再拷贝个.ycm_extra_conf.py。

# This file is NOT licensed under the GPLv3, which is the license for the rest
# of YouCompleteMe.
#
# Here's the license text for this file:
#
# This is free and unencumbered software released into the public domain.
#
# Anyone is free to copy, modify, publish, use, compile, sell, or
# distribute this software, either in source code form or as a compiled
# binary, for any purpose, commercial or non-commercial, and by any
# means.
#
# In jurisdictions that recognize copyright laws, the author or authors
# of this software dedicate any and all copyright interest in the
# software to the public domain. We make this dedication for the benefit
# of the public at large and to the detriment of our heirs and
# successors. We intend this dedication to be an overt act of
# relinquishment in perpetuity of all present and future rights to this
# software under copyright law.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
# For more information, please refer to <http://unlicense.org/>

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',
'-Wextra',
#'-Werror',
#'-Wc++98-compat',
'-Wno-long-long',
'-Wno-variadic-macros',
'-fexceptions',
'-stdlib=libc++',
# 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'.
'-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++',
'-I',
'.',
'-isystem',
'/usr/include',
'-isystem',
'/usr/local/include',
'-isystem',
'/Library/Developer/CommandLineTools/usr/include',
'-isystem',
'/Library/Developer/CommandLineTools/usr/bin/../lib/c++/v1',
]

# 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
#
# 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_ )

    # NOTE: This is just for YouCompleteMe; it's highly likely that your project
    # does NOT need to remove the stdlib flag. DO NOT USE THIS IN YOUR
    # ycm_extra_conf IF YOU'RE NOT 100% SURE YOU NEED IT.
    #try:
    #  final_flags.remove( '-stdlib=libc++' )
    #except ValueError:
    #  pass
  else:
    relative_to = DirectoryOfThisScript()
    final_flags = MakeRelativePathsInFlagsAbsolute( flags, relative_to )

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

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# This file is NOT licensed under the GPLv3, which is the license for the rest

# of YouCompleteMe.

# Here's the license text for this file:

# This is free and unencumbered software released into the public domain.

# Anyone is free to copy, modify, publish, use, compile, sell, or

# distribute this software, either in source code form or as a compiled

# binary, for any purpose, commercial or non-commercial, and by any

# means.

# In jurisdictions that recognize copyright laws, the author or authors

# of this software dedicate any and all copyright interest in the

# software to the public domain. We make this dedication for the benefit

# of the public at large and to the detriment of our heirs and

# successors. We intend this dedication to be an overt act of

# relinquishment in perpetuity of all present and future rights to this

# software under copyright law.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.

# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR

# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,

# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

# OTHER DEALINGS IN THE SOFTWARE.

# For more information, please refer to <http://unlicense.org/>

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',

'-Wextra',

#'-Werror',

#'-Wc++98-compat',

'-Wno-long-long',

'-Wno-variadic-macros',

'-fexceptions',

'-stdlib=libc++',

# 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'.

'-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++',

'-I',

'.',

'-isystem',

'/usr/include',

'-isystem',

'/usr/local/include',

'-isystem',

'/Library/Developer/CommandLineTools/usr/include',

'-isystem',

'/Library/Developer/CommandLineTools/usr/bin/../lib/c++/v1',

]

# 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

# 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_ )

# NOTE: This is just for YouCompleteMe; it's highly likely that your project

# does NOT need to remove the stdlib flag. DO NOT USE THIS IN YOUR

# ycm_extra_conf IF YOU'RE NOT 100% SURE YOU NEED IT.

#try:

# final_flags.remove( '-stdlib=libc++' )

#except ValueError:

# pass

else:

relative_to = DirectoryOfThisScript()

final_flags = MakeRelativePathsInFlagsAbsolute( flags, relative_to )

return {

'flags': final_flags,

'do_cache': True

}

YouCompleteMe提供的其余功能

YCM除了提供了基本的补全功能,自动提示错误的功能外,还提供了相似tags的功能：

跳转到定义GoToDefinition
跳转到声明GoToDeclaration
以及二者的合体GoToDefinitionElseDeclaration

能够在.vimrc中配置相应的快捷键。

nnoremap <leader>gl :YcmCompleter GoToDeclaration<CR>
nnoremap <leader>gf :YcmCompleter GoToDefinition<CR>
nnoremap <leader>gg :YcmCompleter GoToDefinitionElseDeclaration<CR>

nnoremap <leader>gl :YcmCompleter GoToDeclaration<CR>

nnoremap <leader>gf :YcmCompleter GoToDefinition<CR>

nnoremap <leader>gg :YcmCompleter GoToDefinitionElseDeclaration<CR>

另外，YCM也提供了丰富的配置选项，一样在.vimrc中配置。具体请参考

let g:ycm_error_symbol = '>>'
let g:ycm_warning_symbol = '>*'

1 2	let g:ycm_error_symbol = '>>' let g:ycm_warning_symbol = '>*'

同时，YCM能够打开location-list来显示警告和错误的信息:YcmDiags。我的关于ycm的配置以下：

" for ycm
let g:ycm_error_symbol = '>>'
let g:ycm_warning_symbol = '>*'
nnoremap <leader>gl :YcmCompleter GoToDeclaration<CR>
nnoremap <leader>gf :YcmCompleter GoToDefinition<CR>
nnoremap <leader>gg :YcmCompleter GoToDefinitionElseDeclaration<CR>
nmap <F4> :YcmDiags<CR>

" for ycm

let g:ycm_error_symbol = '>>'

let g:ycm_warning_symbol = '>*'

nnoremap <leader>gl :YcmCompleter GoToDeclaration<CR>

nnoremap <leader>gf :YcmCompleter GoToDefinition<CR>

nnoremap <leader>gg :YcmCompleter GoToDefinitionElseDeclaration<CR>

nmap <F4> :YcmDiags<CR>

YCM提供的跳跃功能采用了vim的jumplist，往前跳和日后跳的快捷键为Ctrl+O以及Ctrl+I。

总结

YouCompleteMe是我用过的最爽的一个自动补全的插件了。以前使用acp时，遇到大文件基本上就卡死了，以致于都不怎么敢使用。因为YCM使用的时C/S结构，部分使用vim脚本编写，部分认为原生代码，使得跑起来速度飞快。

抛弃Vim自带的坑爹的补全吧，抛弃ctags吧，抛弃cscope吧，YCM才是终极的补全神器。

在安装过程当中,我也遇到了很多的坑。一会会发一篇解决这些坑的文章。

最后祝你们码年顺利，一码平川，码到功成。