CDN: trunk URL couldn't be downloaded...
解决方案： 移除trunk源, 执行pod search时遇到该错误，也是移除trunk源
pod repo remove trunk
如果无法解决问题，在podfile文件中添加以下命令：
source 'https://mirrors.tuna.tsinghua.edu.cn/git/CocoaPods/Specs.git'
使用清华的源：
source 'https://mirrors.tuna.tsinghua.edu.cn/git/CocoaPods/Specs.git'
CocoaPods was not able to update the master repo. If this is an unexpected issue and persists you can inspect it running pod repo update --verbose
解决: 把ruby源切换成清华的，然后执行：
pod repo update --verbose
The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods install
git拉了新代码之后， 运行报此错，终端执行pod install无效
解决方案： 退出Xcode， 再执行pod install之后打开程序即可
Unable to find a pod with name, author, summary, or description matching ...
这种情况需要删除search_index.json文件， 我们直接在终端执行下面的命令就可以了
rm ~/Library/Caches/CocoaPods/search_index.json
Couldn't determine repo type for URL: https://cdn.cocoapods.org/
执行pod update的时候报了这个错误
$ cd ~/.cocoapods/repos
$ pod repo remove master
$ git clone https://mirrors.tuna.tsinghua.edu.cn/git/CocoaPods/Specs.git master
上面的命令完成后再在podfile中添加下面一行：
source 'https://mirrors.tuna.tsinghua.edu.cn/git/CocoaPods/Specs.git'
CocoaPods could not find compatible versions for pod
dumb http transport does not support shallow capabilities
这个问题安装Cocoapods需要更新Homebrew产生的。 解决方案如下：
1.切换到homebrew-core目录下
cd "$(brew --repo)/Library/Taps/homebrew/homebrew-core"
2. 设置homebrew源为国内的中科大镜像
git remote set-url origin https://mirrors.ustc.edu.cn/homebrew-core.git
3. 更新
homebrew-coregit -C /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core fetch --unshallow
