更新cocopods遇到can't find gem cocoa

问题记录pod install出错
ck (most recent call last):
2: from /usr/local/bin/pod:23:in <main>' 1: from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems.rb:302:inactivate_bin_path'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems.rb:283:in `find_spec_for_exe': can't find gem cocoapods (>= 0.a) with executable pod (Gem::GemNotFoundException)

解决办法
sudo gem update —system

gem install cocoapods

如果没有用，试试
1.rvm get stable

2.gem install cocoapods