iOS Xcode 14 创建新项目Pod init及Pod install 报错

背景

今天看到群里有同学在咨询如下问题：

就是说Xcode 14 创建的新项目，无法进行Pod install。

出于好奇，我这边也创建了一个新项目，然后执行Pod init，果然得到了一样的错误。具体错误如下：

Traceback (most recent call last):
	18: from /Users/mengruirui/.rbenv/versions/2.6.6/bin/pod:23:in `<main>'
	17: from /Users/mengruirui/.rbenv/versions/2.6.6/bin/pod:23:in `load'
	16: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/bin/pod:55:in `<top (required)>'
	15: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/command.rb:52:in `run'
	14: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:334:in `run'
	13: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/command/install.rb:52:in `run'
	12: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer.rb:161:in `install!'
	11: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer.rb:240:in `resolve_dependencies'
	10: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/user_interface.rb:64:in `section'
	 9: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer.rb:241:in `block in resolve_dependencies'
	 8: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer.rb:416:in `analyze'
	 7: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer/analyzer.rb:106:in `analyze'
	 6: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer/analyzer.rb:1184:in `inspect_targets_to_integrate'
	 5: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/user_interface.rb:64:in `section'
	 4: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer/analyzer.rb:1189:in `block in inspect_targets_to_integrate'
	 3: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer/analyzer.rb:1189:in `each'
	 2: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/installer/analyzer.rb:1190:in `block (2 levels) in inspect_targets_to_integrate'
	 1: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/xcodeproj-1.21.0/lib/xcodeproj/project.rb:113:in `open'
/Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/xcodeproj-1.21.0/lib/xcodeproj/project.rb:228:in `initialize_from_file': [Xcodeproj] Unknown object version (56). (RuntimeError)
	9: from /Users/mengruirui/.rbenv/versions/2.6.6/bin/pod:23:in `<main>'
	8: from /Users/mengruirui/.rbenv/versions/2.6.6/bin/pod:23:in `load'
	7: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/bin/pod:55:in `<top (required)>'
	6: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/command.rb:52:in `run'
	5: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:324:in `run'
	4: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:337:in `rescue in run'
	3: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:396:in `handle_exception'
	2: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/command.rb:66:in `report_error'
	1: from /Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/user_interface/error_report.rb:34:in `report'
/Users/mengruirui/.rbenv/versions/2.6.6/lib/ruby/gems/2.6.0/gems/cocoapods-1.11.2/lib/cocoapods/user_interface/error_report.rb:34:in `force_encoding': can't modify frozen String (FrozenError)

解决

查看错误日志发现有一条很重要的信息，应该是版本不匹配导致的，那应该和升级Xcode 14有关系。

in `initialize_from_file': [Xcodeproj] Unknown object version (56). (RuntimeError)

然后去GitHub cocoapods 官方仓查看有没有相关信息，果然有同学也遇到了同样的问题。

但是官方还没有给出解决方案。应该后续会有兼容的cocoapods 新版本。
通过与老项目对比发现是compatibilityVersion Xcode 兼容版本不一致，那么我们就可以将这个版本修改到低版本试试呢。

如何修改compatibilityVersion呢？可以通过 Project Format，可以暂时将Project Format 改为Xcode 13.0-compatible
具体如下图：

改完版本后，再次执行 Pod 命令发现不再报错。