Stylus support and tests. Fixes #649

middleman-core/lib/middleman-core/core_extensions/rendering.rb

@@ -68,6 +68,13 @@ module Middleman
             app.register Middleman::Renderers::Less
           rescue LoadError
           end
+
+          # Stylus Support
+          begin
+            require "middleman-core/renderers/stylus"
+            app.register Middleman::Renderers::Stylus
+          rescue LoadError
+          end
         end
 
         alias :included :registered

middleman-core/lib/middleman-core/renderers/stylus.rb

@@ -0,0 +1,28 @@
+require "stylus"
+require "stylus/tilt"
+
+module Middleman
+  module Renderers
+
+    # Sass renderer
+    module Stylus
+
+      # Setup extension
+      class << self
+
+        # Once registered
+        def registered(app)
+          # Default less options
+          app.set :styl, {}
+
+          app.before_configuration do
+            template_extensions :styl => :css
+          end
+        end
+
+        alias :included :registered
+      end
+
+    end
+  end
+end