Sass是一种css的开发工具，它的安装依赖Ruby，没有安装Ruby的请先安装Ruby。

假定你已经安装了Ruby，则可以直接执行如下语句进行安装。

gem install sass

常见错误提示：

1、ERROR: While executing gem … (OpenSSL::SSL::SSLError)

hostname “gems.ruby-china.org” does not match the server certificate

解决办法：

执行命令，查看数据源

gem source -l

结果

*** CURRENT SOURCES ***

https://ruby.taobao.org/
https://gems.ruby-china.org

则可以删除多余的

gem sources --remove https://ruby.taobao.org/
sudo gem update --system

然后重新安装。

2、ERROR: SSL verification error at depth 1: unable to get local issuer certificate (20)

ERROR: You must add /O=Digital Signature Trust Co./CN=DST Root CA X3 to your local trusted store

Fetching: ffi-1.9.18.gem ( 32%)ERROR: SSL verification error at depth 2: self signed certificate in certificate chain (19)

ERROR: Root certificate is not trusted (/C=US/O=GeoTrust Inc./CN=GeoTrust Global CA)

ERROR: While executing gem … (OpenSSL::SSL::SSLError)

hostname “gems.ruby-china.org” does not match the server certificate

3、ERROR: SSL verification error at depth 1: unable to get local issuer certificate (20)

ERROR: You must add /O=Digital Signature Trust Co./CN=DST Root CA X3 to your local trusted store

Fetching: ffi-1.9.18.gem (100%)

Building native extensions. This could take a while…

Successfully installed ffi-1.9.18

ERROR: SSL verification error at depth 2: self signed certificate in certificate chain (19)

ERROR: Root certificate is not trusted (/C=US/O=GeoTrust Inc./CN=GeoTrust Global CA)

Fetching: rb-inotify-0.9.10.gem (100%)

Successfully installed rb-inotify-0.9.10

Fetching: sass-listen-4.0.0.gem (100%)

Successfully installed sass-listen-4.0.0

Fetching: sass-3.5.1.gem (100%)

ERROR: While executing gem … (Errno::EPERM)

Operation not permitted - /usr/bin/sass

遇到以上错误 2和3的解决办法

sudo gem install -n /usr/local/bin sass

查看

sass -v

则会正确显示Sass版本号。

2017年12月28日更新：

Mac更新系统后，Ruby由2.0升级到2.3，再次使用Sass时候，发现报错。

于是决定升级SaaS，重新安装时遇到错误。最后找到解决方案：

先安装libgmp-dev，再重新安装即可。

brew install libgmp-dev
sudo gem install -n /usr/local/bin sass