Mac 升级系统ruby

最近在执行pod install老报错，最要是更新xcode时，更新了Mac 系统版本

pod install 部分错误：

    /Users/zzy/.gem/ruby/2.6.0/gems/cocoapods-1.11.3/lib/cocoapods/user_interface/error_report.rb:34:in `force_encoding': can't modify frozen String (FrozenError)
    from /Users/zzy/.gem/ruby/2.6.0/gems/cocoapods-1.11.3/lib/cocoapods/user_interface/error_report.rb:34:in `report'
    from /Users/zzy/.gem/ruby/2.6.0/gems/cocoapods-1.11.3/lib/cocoapods/command.rb:66:in `report_error'
    from /Library/Ruby/Gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:396:in `handle_exception'
    from /Library/Ruby/Gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:337:in `rescue in run'
    from /Library/Ruby/Gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:324:in `run'
    from /Users/zzy/.gem/ruby/2.6.0/gems/cocoapods-1.11.3/lib/cocoapods/command.rb:52:in `run'
    from /Users/zzy/.gem/ruby/2.6.0/gems/cocoapods-1.11.3/bin/pod:55:in `<top (required)>'
    from /usr/local/bin/pod:23:in `load'
    from /usr/local/bin/pod:23:in `<main>'

解决方案：
1.系统设置

  sudo chown -R `whoami` /usr/local/Homebrew/
  sudo chown -R $(whoami) $(brew --prefix)/*
  sudo mkdir /usr/local/Frameworks
  sudo chown -R `whoami` /usr/local/Frameworks/

2.brew install ruby

3.设置系统环境变量
查看ruby版本

ruby --version

如果还是显示老版本需要配置环境变量
打开 .zshrc文件，添加

export PATH="/usr/local/opt/ruby/bin:$PATH"
source ~/.zshrc

再次查看ruby版本