安装brew
方式一（网速快的推荐）：
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"方式二（网速慢的推荐）：
curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install >> brew_install
vi brew_install
找到如下代码(新版本HomeBrew可能没有CORE_TAP_REPO这句代码，如果没有不用新增)：
BREW_REPO = "https://github.com/Homebrew/brew".freeze
CORE_TAP_REPO = "https://github.com/Homebrew/homebrew-core".freeze
复制代码更改为：
BREW_REPO = "https://mirrors.ustc.edu.cn/brew.git".freeze
CORE_TAP_REPO = "https://mirrors.ustc.edu.cn/homebrew-core.git".freeze
执行脚本：
/usr/bin/ruby brew_install
此时脚本应该停在
==> Tapping homebrew/core
Cloning into ‘/usr/local/Homebrew/Library/Taps/homebrew/homebrew-core’…
解决方法，手动执行下面这句命令，更换为中科院的镜像：
git clone git://mirrors.ustc.edu.cn/homebrew-core.git/ /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core --depth=1
复制代码然后把homebrew-core的镜像地址也设为中科院的国内镜像
cd $(brew --repo)
git remote set-url origin https://mirrors.ustc.edu.cn/brew.git
cd "$(brew --repo)/Library/Taps/homebrew/homebrew-core"
git remote set-url origin https://mirrors.ustc.edu.cn/homebrew-core.git
执行更新：
brew update
检查错误：
brew doctor卸载brew
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/uninstall)"
