/Users/wxy/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems.rb:270:in `find_spec_for_exe': can't find gem cocoapods (>= 0.a) (Gem::GemNotFoundException)
    from /Users/wxy/.rvm/rubies/ruby-2.3.3/lib/ruby/site_ruby/2.3.0/rubygems.rb:298:in `activate_bin_path'
    from /Users/wxy/.rvm/rubies/ruby-2.3.3/bin/pod:22:in `<main>'

• 产生原因：电脑本地的ruby版本是2.3.3，再安装一个2.0.0的版本并设置成默认版本

rvm install 2.0.0

• 将2.0.0版本设置成默认版本

rvm 2.0.0 --default

• 卸载之前安装的cocoapods

sudo gem uninstall cocoapods

• 重新安装cocoapods

sudo gem install cocoapods

• 重新安装完毕，查看下pod版本看看

pod --version

• 终端显示版本号，没有报错表示安装成功