新版 Mac M2 安装老 saas 项目 报 Gem sass is not installed 问题解决
换了新电脑，需要把老项目 git 拉下来再跑起来的时候发现生成样式文件的时候会报这个错误 ，（N年前老项目，用的是 node-sass, gulp-ruby-sass@2.1.1 版本比较老旧，但项目还是要跑，工作还是要做呀）
Error in plugin 'gulp-ruby-sass'
Message:
Gem sass is not installed.
于是百度一下，说要让安装 gem sass
$ gem sources --remove https: //rubygems.org/ $ gem sources --add https://ruby.taobao.org/ $ gem sources -l *** CURRENT SOURCES *** https://ruby.taobao.org 然后运行: $ sudo gem install sass
结果 淘宝源不给力，已经 404了，只能想使用原始源了
但在安装 gem install sass 的时候一直报这个错：
Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options.
还有一些其它错误，但上面这句是关键，根据提示进入到这个路径
Library/Ruby/Gems/2.6.0/extensions/universal-darwin-21/2.6.0/ffi-1.15.5
查看log
cat mkmf.log
下面是显示内容
package configuration for libffi is not found
"xcrun clang -o conftest -I/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/universal-darwin21 -I/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby/backward -I/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -D_DARWIN_UNLIMITED_SELECT -D_REENTRANT -g -Os -pipe -DHAVE_GCC_ATOMIC_BUILTINS -DUSE_FFI_CLOSURE_ALLOC conftest.c -L. -L/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib -L. -L/AppleInternal/Library/BuildRoots/20d6c351-ee94-11ec-bcaf-7247572f23b4/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.5.Internal.sdk/usr/local/lib -lruby.2.6 "
In file included from conftest.c:1:
In file included from /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby.h:33:
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby/ruby.h:24:10: fatal error: 'ruby/config.h' file not found
#include "ruby/config.h"
^~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby/ruby.h:24:10: note: did not find header 'config.h' in framework 'ruby' (loaded from '/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks')
1 error generated.
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: int main(int argc, char **argv)
4: {
5: return 0;
6: }
/* end */
上面日志红色部分很关键，这个目录下的这个包在电脑中居然没有此版本，本地的文件夹是 universal-darwin22 ，然后我打开以前可以使用的Mac本的同样的地址文件夹里的版本是 21 ，于是把21版本文件夹考到新 Mac 本的相同路径里，再次运行
sudo gem install sass
下面是提示：
Ruby Sass has reached end-of-life and should no longer be used.
* If you use Sass as a command-line tool, we recommend using Dart Sass, the new
primary implementation: https://sass-lang.com/install
* If you use Sass as a plug-in for a Ruby web framework, we recommend using the
sassc gem: https://github.com/sass/sassc-ruby#readme
* For more details, please refer to the Sass blog:
https://sass-lang.com/blog/posts/7828841
Successfully installed sass-3.7.4
Parsing documentation for sass-3.7.4
Done installing documentation for sass after 1 seconds
1 gem installed
非常完美！再次启动项目，试着编译一次 css , ok 了！
再次强调一下，安装项目报错不要紧，但一定要看报错日志，一定要看报错日志，一定要看报错日志，重要的事情说三次。
