Add general purpose RakeHelper class for opal gems to use

Rakefile

@@ -2,6 +2,9 @@ require 'bundler'
 Bundler.require
 Bundler::GemHelper.install_tasks
 
+require 'opal/rake_helper'
+Opal::RakeHelper.install_tasks
+
 namespace :github do
   task :upload_assets do
     require 'octokit'
@@ -25,7 +28,7 @@ require 'rack'
 require 'webrick'
 require 'opal-sprockets'
 
-# mspec/rubyspec use a top level "language_version" to require relative specs.
+# rubyspec uses a top level "language_version" to require relative specs.
 # We can't do this at runtime, so we hijack the method (and make sure we only
 # do this at the top level). We figure out which file we are including, and
 # add it to our require list
@@ -61,8 +64,7 @@ class SpecEnvironment < Opal::Environment
   end
 
   def build_min file = 'build/specs.min.js'
-    require 'uglifier'
-    build Uglifier.compile(specs), file
+    build Opal::RakeHelper.uglify(specs), file
   end
 
   def build code = specs, file = 'build/specs.js'
@@ -105,17 +107,6 @@ class RunSpec
   def build_specs
     SpecEnvironment.new.build
   end
-
-  # Only if OPAL_UGLIFY is set
-  def uglify(str)
-    if ENV['OPAL_UGLIFY']
-      require 'uglifier'
-      puts " * uglifying"
-      Uglifier.compile(str)
-    else
-      str
-    end
-  end
 end
 
 require 'rspec/core/rake_task'
@@ -187,8 +178,8 @@ task :dist do
     puts "* building #{lib}..."
 
     src = env[lib].to_s
-    min = uglify src
-    gzp = gzip min
+    min = Opal::RakeHelper.uglify src
+    gzp = Opal::RakeHelper.gzip min
 
     File.open("build/#{lib}.js", 'w+')        { |f| f << src }
     File.open("build/#{lib}.min.js", 'w+')    { |f| f << min } if min
@@ -206,27 +197,3 @@ desc "Rebuild grammar.rb for opal parser"
 task :racc do
   %x(racc -l lib/opal/grammar.y -o lib/opal/grammar.rb)
 end
-
-# Used for uglifying source to minify
-def uglify(str)
-  IO.popen('uglifyjs', 'r+') do |i|
-    i.puts str
-    i.close_write
-    return i.read
-  end
-rescue Errno::ENOENT
-  $stderr.puts '"uglifyjs" command not found (install with: "npm install -g uglify-js")'
-  nil
-end
-
-# Gzip code to check file size
-def gzip(str)
-  IO.popen('gzip -f', 'r+') do |i|
-    i.puts str
-    i.close_write
-    return i.read
-  end
-rescue Errno::ENOENT
-  $stderr.puts '"gzip" command not found, it is required to produce the .gz version'
-  nil
-end

lib/opal/rake_helper.rb

@@ -0,0 +1,52 @@
+require 'opal'
+
+module Opal
+  class RakeHelper
+    include Rake::DSL if defined? Rake::DSL
+
+    class << self
+      attr_accessor :instance
+
+      def install_tasks
+        self.new.install_tasks
+      end
+
+      def expose(*names)
+        names.each do |name|
+          define_singleton_method(name) do |*args|
+            instance.__send__(name, *args)
+          end
+        end
+      end
+    end
+
+    expose :uglify, :gzip
+
+    def initialize
+      install_tasks
+
+      RakeHelper.instance = self
+    end
+
+    def install_tasks
+      namespace :opal do
+      end
+    end
+
+    def uglify(str)
+      IO.popen('uglifyjs', 'r+') do |i|
+        i.puts str
+        i.close_write
+        return i.read
+      end
+    end
+
+    def gzip(str)
+      IO.popen('gzip -f', 'r+') do |i|
+        i.puts str
+        i.close_write
+        return i.read
+      end
+    end
+  end
+end

opal.gemspec

@@ -20,7 +20,6 @@ Gem::Specification.new do |s|
   s.add_dependency 'source_map'
 
   s.add_development_dependency 'mspec', '1.5.18'
-  s.add_development_dependency 'uglifier'
   s.add_development_dependency 'rake'
   s.add_development_dependency 'racc'
   s.add_development_dependency 'opal-sprockets', '~> 0.2.1'