sudo gem install cocoapods安裝後，發現輸完密碼一直沒動靜。問題是因爲“https://rubygems.org/“被牆了，更換gem源爲“https://gems.ruby-china.org/“即可：
gem sources --add https://gems.ruby-china.org/ --remove https://rubygems.org/再次執行“sudo gem install cocoapods“仍然報錯：
ERROR: While executing gem ... (Gem::DependencyError)
Unable to resolve dependencies: cocoapods requires cocoapods-core (= 1.2.0), cocoapods-downloader (< 2.0, >= 1.1.3), cocoapods-trunk (< 2.0, >= 1.1.2), molinillo (~> 0.5.5), xcodeproj (< 2.0, >= 1.4.1), colored (~> 1.2), escape (~> 0.0.4), fourflusher (~> 2.0.1), gh_inspector (~> 1.0), nap (~> 1.0), ruby-macho (~> 0.2.5); activesupport requires i18n (>= 0.6.9, ~> 0.6), tzinfo (~> 1.1), minitest (~> 5.1), thread_safe (~> 0.1); cocoapods-plugins requires nap (>= 0)出現這個問題是因爲ruby版本太低，執行：
gem update --system接着報錯：
Updating rubygems-update
Fetching: rubygems-update-2.6.7.gem (100%)
ERROR: While executing gem ... (Gem::FilePermissionError)
You don't have write permissions for the /Library/Ruby/Gems/2.0.0 directory.報這個錯是因爲權限不夠，加上sudo：
sudo gem update --system接着就開始babala，開始安裝了：
Updating rubygems-update
……
……
……
ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/xcodeproj撞到最後又丫的報錯啦。網上搜索了一下，解決方案是：
sudo gem install -n /usr/local/bin cocoapods坑有點多，也不怕嚇壞小朋友，真是的……