CocoaPods 升级报错

内容

Traceback (most recent call last):
 4: from /Users/iosdev/.rvm/gems/ruby-2.5.3/bin/ruby_executable_hooks:24:in `<main>'
 3: from /Users/iosdev/.rvm/gems/ruby-2.5.3/bin/ruby_executable_hooks:24:in `eval'
 2: from /usr/local/bin/pod:23:in `<main>'
 1: from /Users/iosdev/.rvm/rubies/ruby-2.5.3/lib/ruby/site_ruby/2.5.0/rubygems.rb:308:in `activate_bin_path'
/Users/iosdev/.rvm/rubies/ruby-2.5.3/lib/ruby/site_ruby/2.5.0/rubygems.rb:289:in `find_spec_for_exe': can't find gem cocoapods (>= 0.a) with executable pod (Gem::GemNotFoundException)

解决：

1、sudo gem update --system
2、gem install cocoapods