Use Opal::Builder to simpify opal-parser.js

lib/opal.rb

@@ -18,6 +18,10 @@ def self.parse(source, options = {})
     Parser.new.parse(source, options)
   end
 
+  def self.gem_dir
+    File.expand_path('..', __FILE__.untaint)
+  end
+
   def self.core_dir
     File.expand_path('../../corelib', __FILE__.untaint)
   end

lib/opal/builder.rb

@@ -10,8 +10,8 @@ def self.build(name)
       Builder.new.build name
     end
 
-    def initialize
-      @paths = Opal.paths.clone
+    def initialize(paths = nil)
+      @paths = paths || Opal.paths.clone
       @handled = {}
     end
 

stdlib/opal-parser.js.erb

@@ -1,10 +1,4 @@
-<% require_asset 'racc' %>
-<% require_asset 'strscan' %>
-
-// We need (some) of the libs from our real ruby parser (not in sprockets load path)
-<% %w(opal/version opal/grammar opal/lexer opal/parser opal/target_scope opal/sexp opal/lexer_scope opal/grammar_helpers opal/fragment opal).each do |f| %>
-<%= Opal::RequireParser.parse File.read(File.join Opal.core_dir, '..', 'lib', "#{f}.rb") %>
-<% end %>
+<%= Opal::Builder.new([Opal.gem_dir, Opal.std_dir]).build('opal') %>
 
 Opal.parse = function(str) {
   return Opal.Opal.Parser.$new().$parse(str);

stdlib/racc/parser.rb.rb

@@ -0,0 +1,3 @@
+require 'racc/parser'
+
+# FIXME: Builder cannot currently handle require('racc/parser.rb') with extname