Windows RubyInstaller support with rake-compiler

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "ext/libsass"]
 	path = ext/libsass
-  url = git://github.com/sass/libsass.git
+	url = git://github.com/sass/libsass.git

README.md

@@ -6,7 +6,7 @@ This gem combines the speed of `libsass`, the [Sass C implementation](https://gi
 
 ### libsass Version
 
-[3.5.2](https://github.com/sass/libsass/releases/tag/3.5.2)
+[d225a09a](https://github.com/sass/libsass/commit/d225a09a152050d569c077f97bb944c8dc819d6f)
 
 ## Installation
 

Rakefile

@@ -4,12 +4,17 @@ rescue LoadError
   puts 'Cannot load bundler/gem_tasks'
 end
 
-require 'tasks/libsass'
-
 task default: :test
 
+require 'rake/extensiontask'
+Rake::ExtensionTask.new do |ext|
+  ext.name = 'libsass'
+  ext.ext_dir = 'ext'
+  ext.lib_dir = 'lib'
+end
+
 desc "Run all tests"
-task test: 'libsass:compile' do
+task test: 'compile:libsass' do
   $LOAD_PATH.unshift('lib', 'test')
   Dir.glob('./test/**/*_test.rb') { |f| require f }
 end

ext/extconf.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+gem_root = File.expand_path('..', __dir__)
+libsass_dir = File.join(gem_root, 'ext', 'libsass').gsub(' ', '\ ')
+pwd = Dir.pwd
+
+File.write 'Makefile', <<-MAKEFILE
+libsass.so: | #{libsass_dir}
+	DESTDIR='#{pwd}' PREFIX= $(MAKE) -C #{libsass_dir} '#{pwd}/lib/libsass.so'
+	mv '#{pwd}/lib/libsass.so' '#{pwd}/libsass.so'
+
+#{libsass_dir}:
+	cd '#{gem_root}'
+	git submodule update --init
+MAKEFILE
+
+$makefile_created = true

sassc.gemspec

@@ -23,13 +23,15 @@ Gem::Specification.new do |spec|
 
   spec.require_paths = ["lib"]
 
-  spec.extensions    = ["ext/Rakefile"]
+  spec.platform      = Gem::Platform::RUBY
+  spec.extensions    = ["ext/extconf.rb"]
 
   spec.add_development_dependency "minitest", "~> 5.5.1"
   spec.add_development_dependency "minitest-around"
   spec.add_development_dependency "test_construct"
   spec.add_development_dependency "pry"
   spec.add_development_dependency "bundler"
+  spec.add_development_dependency "rake-compiler"
 
   spec.add_dependency "rake"
   spec.add_dependency "ffi", "~> 1.9.6"