Implementing the RoyFilter

.gitignore

@@ -1,5 +1,6 @@
 *.gem
 *.rbc
+*.swp
 .bundle
 .config
 .yardoc

lib/rake-pipeline-web-filters.rb

@@ -25,4 +25,5 @@ module Filters
 require "rake-pipeline-web-filters/chained_filter"
 require "rake-pipeline-web-filters/less_filter"
 require "rake-pipeline-web-filters/handlebars_filter"
+require "rake-pipeline-web-filters/roy_filter"
 require "rake-pipeline-web-filters/helpers"

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

@@ -92,6 +92,12 @@ def less(*args, &block)
     def handlebars(*args, &block)
       filter(Rake::Pipeline::Web::Filters::HandlebarsFilter, *args, &block)
     end
+
+    # Add a new {RoyFilter} to the pipeline.
+    # @see RoyFilter#initialize
+    def roy(*args, &block)
+      filter(Rake::Pipeline::Web::Filters::RoyFilter, *args, &block)
+    end
   end
 
   module ProjectHelpers

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

@@ -0,0 +1,56 @@
+require 'rake-pipeline-web-filters/filter_with_dependencies'
+
+module Rake::Pipeline::Web::Filters
+  # Public: The RoyFilter compiles scripts written in Roy to JavaScript.
+  #
+  # This filter depends on the roy-lang gem.
+  #
+  # Examples
+  #
+  #   The following is an example Assetfile usage.
+  #
+  #   output "public"
+  #
+  #   input "assets" do
+  #     match "*.roy" do
+  #       roy
+  #     end
+  #   end
+  class RoyFilter < Rake::Pipeline::Filter
+    include Rake::Pipeline::Web::Filters::FilterWithDependencies
+
+    # Public: Returns the hash of options used when compiling.
+    attr_reader :options
+
+    # Public: Initializes a RoyFilter.
+    #
+    # options - The Hash of options to use when compiling (default: {}):
+    #           See the roy-lang gem for available options.
+    # block   - A block to map input names to ouput names (defaults to
+    #           mapping .roy files to .js).
+    def initialize(options = {}, &block)
+      super &(block || ->input {input.sub(/\.roy\z/, ".js")})
+      @options = options
+    end
+
+    protected
+    # Internal: Generates a JavaScript output file containing each
+    # compiled input.
+    #
+    # inputs - Array of FileWrappers of Roy files.
+    # output - A FileWrapper of a JavaScript file.
+    def generate_output(inputs, output)
+      inputs.each do |input|
+        output.write Roy.compile(input.read, @options)
+      end
+    end
+
+    private
+    # Internal: Defines the external dependencies of this filter.
+    #
+    # Returns an Array of the dependencies.
+    def external_dependencies
+      ["roy-lang"]
+    end
+  end
+end

rake-pipeline-web-filters.gemspec

@@ -27,5 +27,7 @@ Gem::Specification.new do |gem|
   gem.add_development_dependency "yui-compressor"
   gem.add_development_dependency "uglifier"
   gem.add_development_dependency "less"
+  gem.add_development_dependency "therubyracer"
   gem.add_development_dependency "json"
+  gem.add_development_dependency "roy-lang"
 end

spec/coffee_script_filter_spec.rb

@@ -102,7 +102,7 @@ def setup_filter(filter)
       tasks = filter.generate_rake_tasks
       lambda {
         tasks.each(&:invoke)
-      }.should raise_error(ExecJS::RuntimeError, /Error compiling input.coffee. reserved word "function" on line 1/i)
+      }.should raise_error(ExecJS::RuntimeError, /Error compiling input.coffee\..*reserved word "function" on line 1/i)
     end
   end
 

spec/helpers_spec.rb

@@ -95,6 +95,13 @@ def filter
       filter.should be_kind_of(Rake::Pipeline::Web::Filters::HandlebarsFilter)
     end
   end
+
+  describe "#roy" do
+    it "creates a RoyFilter" do
+      dsl.roy
+      filter.should be_kind_of(Rake::Pipeline::Web::Filters::RoyFilter)
+    end
+  end
 end
 
 describe "ProjectHelpers" do

spec/roy_filter_spec.rb

@@ -0,0 +1,45 @@
+describe "RoyFilter" do
+  let(:file_wrapper_class){Rake::Pipeline::SpecHelpers::MemoryFileWrapper}
+  let(:rake_app){Rake::Application.new}
+
+  let(:encoding){"UTF-8"}
+  let(:input_path){"/in"}
+  let(:output_path){"/out"}
+  let(:input_name){"a.roy"}
+  let(:output_name){"a.js"}
+
+  let(:input_file){file_wrapper_class.new(input_path, input_name, encoding, input)}
+  let(:output_file){file_wrapper_class.new(output_path, output_name, encoding)}
+
+  subject {
+    filter = Rake::Pipeline::Web::Filters::RoyFilter.new(options)
+    filter.file_wrapper_class = file_wrapper_class
+    filter.input_files = [input_file]
+    filter.output_root = output_path
+    filter.rake_application = rake_app
+    filter
+  }
+
+  describe "#generate_output" do
+    context "when default options are used" do
+      let(:options){{}}
+      let(:output){<<-JS.gsub(/^\s*/,"")
+          (function() {
+            var x = 10;
+          })();
+        JS
+      }
+      context "when the input is valid" do
+        let(:input){"let x = 10"}
+        before{subject.generate_rake_tasks.each(&:invoke)}
+        specify{subject.output_files.should == [output_file]}
+        specify{file_wrapper_class.files["#{output_path}/#{output_name}"].body.should == output}
+        specify{file_wrapper_class.files["#{output_path}/#{output_name}"].encoding.should == encoding}
+      end
+      context "when the input is invalid" do
+        let(:input){"var = x, 10"}
+        specify{->{subject.generate_rake_tasks.each(&:invoke)}.should raise_error}
+      end
+    end
+  end
+end

spec/spec_helper.rb

@@ -101,4 +101,8 @@ def tmp
   config.after do
     Dir.chdir(original)
   end
+
+  config.treat_symbols_as_metadata_keys_with_true_values = true
+  config.run_all_when_everything_filtered = true
+  config.filter_run :focus
 end