Mac -> Ruby -> Gem -> C

1. 先翻墙
2. 首先安装RVM

  curl -sSL https://get.rvm.io | bash -s stable

2.1 检测是否有效:

 rvm -v

3. 安装新版Ruby

rvm requirements
rvm install 2.4

3.1 检测是否有效

ruby -v
gem -v

4. 安装CocoaPods

gem install cocoapods