今天，新建了一个项目，使用Cocoapods的pod init命令，报了如下错误：

pod init

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### Command


/usr/local/bin/pod init


### Report

* What did you do?

* What did you expect to happen?

* What happened instead?


### Stack


   CocoaPods : 1.4.0
        Ruby : ruby 2.2.5p319 (2016-04-26 revision 54774) [x86_64-darwin17]
    RubyGems : 2.6.14
        Host : Mac OS X 10.13.4 (17E199)
       Xcode : 9.3 (9E145)
         Git : git version 2.15.1 (Apple Git-101)
Ruby lib dir : /Users/yuhua/.rvm/rubies/ruby-2.2.5/lib
Repositories : master - https://github.com/CocoaPods/Specs.git @ cdddceeb7e89713952368711f41e21460887fe03


### Plugins


cocoapods-deintegrate : 1.0.2
cocoapods-plugins     : 1.0.0
cocoapods-search      : 1.0.0
cocoapods-stats       : 1.0.0
cocoapods-trunk       : 1.3.0
cocoapods-try         : 1.1.0


### Error


RuntimeError - [Xcodeproj] Unknown object version.
/Users/yuhua/.rvm/gems/ruby-2.2.5@global/gems/xcodeproj-1.5.4/lib/xcodeproj/project.rb:217:in `initialize_from_file'
/Users/yuhua/.rvm/gems/ruby-2.2.5@global/gems/xcodeproj-1.5.4/lib/xcodeproj/project.rb:102:in `open'
/Users/yuhua/.rvm/gems/ruby-2.2.5@global/gems/cocoapods-1.4.0/lib/cocoapods/command/init.rb:41:in `validate!'
/Users/yuhua/.rvm/gems/ruby-2.2.5@global/gems/claide-1.0.2/lib/claide/command.rb:333:in `run'
/Users/yuhua/.rvm/gems/ruby-2.2.5@global/gems/cocoapods-1.4.0/lib/cocoapods/command.rb:52:in `run'
/Users/yuhua/.rvm/gems/ruby-2.2.5@global/gems/cocoapods-1.4.0/bin/pod:55:in `<top (required)>'
/usr/local/bin/pod:23:in `load'
/usr/local/bin/pod:23:in `<main>'
/Users/yuhua/.rvm/gems/ruby-2.2.5/bin/ruby_executable_hooks:15:in `eval'
/Users/yuhua/.rvm/gems/ruby-2.2.5/bin/ruby_executable_hooks:15:in `<main>'


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[!] Oh no, an error occurred.

Search for existing GitHub issues similar to yours:
https://github.com/CocoaPods/CocoaPods/search?q=%5BXcodeproj%5D+Unknown+object+version.&type=Issues

If none exists, create a ticket, with the template displayed above, on:
https://github.com/CocoaPods/CocoaPods/issues/new

Be sure to first read the contributing guide for details on how to properly submit a ticket:
https://github.com/CocoaPods/CocoaPods/blob/master/CONTRIBUTING.md

Don't forget to anonymize any private data!

Looking for related issues on cocoapods/cocoapods...
 - Pod init. Unknown object version
   https://github.com/CocoaPods/CocoaPods/issues/7907 [closed] [2 comments]
   a week ago

 - RuntimeError - [Xcodeproj] Unknown object version.
   https://github.com/CocoaPods/CocoaPods/issues/7697 [closed] [27 comments]
   a day ago

 - Unknown object version
   https://github.com/CocoaPods/CocoaPods/issues/7760 [closed] [1 comment]
   21 May 2018

and 41 more at:
https://github.com/cocoapods/cocoapods/search?q=[Xcodeproj]%20Unknown%20object%20version.&type=Issues&utf8=✓

解决办法

注意其中的错误提示：

### Error


RuntimeError - [Xcodeproj] Unknown object version.

好了，知道了，版本的问题。只需要用Xcode打开项目，修改项目Project Format为8.0即可。

屏幕快照 2018-07-13 下午9.59.50.png

好了，愉快的使用吧。