Support for Stylus

.gitignore

@@ -15,3 +15,5 @@ spec/reports
 test/tmp
 test/version_tmp
 tmp
+node_modules
+.project

lib/rake-pipeline-web-filters.rb

@@ -16,6 +16,7 @@ module Filters
 require "rake-pipeline-web-filters/minispade_filter"
 require "rake-pipeline-web-filters/neuter_filter"
 require "rake-pipeline-web-filters/sass_filter"
+require "rake-pipeline-web-filters/stylus_filter"
 require "rake-pipeline-web-filters/tilt_filter"
 require "rake-pipeline-web-filters/coffee_script_filter"
 require "rake-pipeline-web-filters/yui_javascript_filter"

lib/rake-pipeline-web-filters/helpers.rb

@@ -32,6 +32,12 @@ def sass(*args, &block)
       filter(Rake::Pipeline::Web::Filters::SassFilter, *args, &block)
     end
     alias_method :scss, :sass
+
+    # Add a new {StylusFilter} to the pipeline.
+    # @see StylusFilter#initialize
+    def stylus(*args, &block)
+      filter(Rake::Pipeline::Web::Filters::StylusFilter, *args, &block)
+    end
 
     # Add a new {TiltFilter} to the pipeline.
     # @see TiltFilter#initialize

lib/rake-pipeline-web-filters/stylus_filter.rb

@@ -0,0 +1,59 @@
+require 'rake-pipeline-web-filters/filter_with_dependencies'
+
+module Rake::Pipeline::Web::Filters
+  # A filter that compiles input files written in Stylus
+  # to CSS using the Stylus compiler
+  #
+  # Requires http://rubygems.org/gems/stylus
+  #
+  # You will need the `node` command on your runtime
+  # for this to work. See https://github.com/lucasmazza/ruby-stylus
+  # for more information.
+  #
+  # @example
+  #   !!!ruby
+  #   Rake::Pipeline.build do
+  #     input "app/assets", "**/*.styl"
+  #     output "public"
+  #
+  #     # Compile each Stylus file under the app/assets
+  #     # directory.
+  #     filter Rake::Pipeline::Web::Filters::StylusFilter
+  #   end
+  class StylusFilter < Rake::Pipeline::Filter
+    include Rake::Pipeline::Web::Filters::FilterWithDependencies
+
+    attr_reader :options
+
+    # @param [Hash] options options to pass to Stylus
+    # @option options [Array] :use Plugins to import from Node
+    # @option options [Boolean] :debug Output debug info
+    # @param [Proc] block a block to use as the Filter's
+    #   {#output_name_generator}.
+    def initialize(options={}, &block)
+      block ||= proc { |input| input.sub(/\.(styl)$/, '.css') }
+      super(&block)
+      @options = options
+    end
+
+    def generate_output(inputs, output)
+      options.each do |key, value|
+        if key == :use
+          Stylus.send key, *value
+          next
+        end
+        Stylus.send "#{key}=", value
+      end
+      inputs.each do |input|
+        output.write Stylus.compile(input.read)
+      end
+    end
+
+  private
+
+    def external_dependencies
+      [ 'stylus' ]
+    end
+
+  end
+end

rake-pipeline-web-filters.gemspec

@@ -29,4 +29,5 @@ Gem::Specification.new do |gem|
   gem.add_development_dependency "less"
   gem.add_development_dependency "json"
   gem.add_development_dependency "therubyracer"
+  gem.add_development_dependency "stylus"
 end

spec/helpers_spec.rb

@@ -25,6 +25,13 @@ def filter
       filter.should be_kind_of(Rake::Pipeline::Web::Filters::SassFilter)
     end
   end
+
+  describe "#stylus" do
+    it "creates a StylusCompiler" do
+      dsl.stylus
+      filter.should be_kind_of(Rake::Pipeline::Web::Filters::StylusFilter)
+    end
+  end
 
   describe "#tilt" do
     it "creates a TiltFilter" do

spec/stylus_filter_spec.rb

@@ -0,0 +1,69 @@
+describe "StylusFilter" do
+  StylusFilter ||= Rake::Pipeline::Web::Filters::StylusFilter
+  MemoryFileWrapper ||= Rake::Pipeline::SpecHelpers::MemoryFileWrapper
+
+  let(:styl_input) { <<-STYLUS }
+border-radius()
+  -webkit-border-radius arguments
+  -moz-border-radius arguments
+  border-radius arguments
+  
+body
+  font 12px Helvetica, Arial, sans-serif
+  
+a.button
+  border-radius 5px
+STYLUS
+
+  let(:expected_css_output) { <<-CSS }
+body {
+  font: 12px Helvetica, Arial, sans-serif;
+}
+a.button {
+  -webkit-border-radius: 5px;
+  -moz-border-radius: 5px;
+  border-radius: 5px;
+}
+CSS
+
+  def input_file(name, content)
+    MemoryFileWrapper.new("/path/to/input", name, "UTF-8", content)
+  end
+
+  def output_file(name)
+    MemoryFileWrapper.new("/path/to/output", name, "UTF-8")
+  end
+
+  def setup_filter(filter, input=styl_input)
+    filter.file_wrapper_class = MemoryFileWrapper
+    filter.input_files = [input_file("border.styl", input)]
+    filter.output_root = "/path/to/output"
+    filter.rake_application = Rake::Application.new
+    filter
+  end
+
+  it "generates output" do
+    filter = setup_filter StylusFilter.new
+
+    filter.output_files.should == [output_file("border.css")]
+
+    tasks = filter.generate_rake_tasks
+    tasks.each(&:invoke)
+
+    file = MemoryFileWrapper.files["/path/to/output/border.css"]
+    file.body.should == expected_css_output
+    file.encoding.should == "UTF-8"
+  end
+
+  describe "naming output files" do
+    it "translates .styl extensions to .css by default" do
+      filter = setup_filter StylusFilter.new
+      filter.output_files.first.path.should == "border.css"
+    end
+
+    it "accepts a block to customize output file names" do
+      filter = setup_filter(StylusFilter.new { |input| "octopus" })
+      filter.output_files.first.path.should == "octopus"
+    end
+  end
+end