Added Mustang V8 as runtime

lib/execjs.rb

@@ -7,6 +7,7 @@ module ExecJS
 
   autoload :ExternalRuntime,  "execjs/external_runtime"
   autoload :RubyRacerRuntime, "execjs/ruby_racer_runtime"
+  autoload :MustangRuntime,   "execjs/mustang_runtime"
   autoload :RubyRhinoRuntime, "execjs/ruby_rhino_runtime"
   autoload :Runtimes,         "execjs/runtimes"
 

lib/execjs/mustang_runtime.rb

@@ -0,0 +1,73 @@
+module ExecJS
+  class MustangRuntime
+    def name
+      "Mustang (Mustang::V8)"
+    end
+
+    def exec(source)
+      context = Context.new
+      context.exec(source)
+    end
+
+    def eval(source)
+      context = Context.new
+      context.eval(source)
+    end
+
+    def compile(source)
+      Context.new(source)
+    end
+
+    def available?
+      require "mustang"
+      true
+    rescue LoadError
+      false
+    end
+
+  end
+end
+
+module ExecJS
+  class MustangRuntime::Context
+
+    def initialize(source = "")
+      @v8_context = ::Mustang::Context.new
+      @v8_context.eval(source)
+    end
+
+    def exec(source, options = {})
+      if /\S/ =~ source
+        eval "(function(){#{source}})()", options
+      end
+    end
+
+    def eval(source, options = {})
+      if /\S/ =~ source
+        unbox @v8_context.eval("(#{source})")
+      end
+    end
+
+    def call(properties, *args)
+      unbox @v8_context.eval(properties).call(*args)
+    rescue NoMethodError
+      raise ProgramError
+    end
+
+    def unbox(value)
+      case value
+      when Mustang::V8::NullClass, Mustang::V8::UndefinedClass, Mustang::V8::Function
+        nil
+      when Mustang::V8::Array
+        value.map { |v| unbox(v) }
+      when Mustang::V8::SyntaxError
+        raise RuntimeError
+      when Mustang::V8::Error
+        raise ProgramError
+      else
+        value.respond_to?(:delegate) ? value.delegate : value
+      end
+    end
+
+  end
+end

lib/execjs/runtimes.rb

@@ -2,6 +2,8 @@ module ExecJS
   module Runtimes
     RubyRacer = RubyRacerRuntime.new
 
+    Mustang = MustangRuntime.new
+
     RubyRhino = RubyRhinoRuntime.new
 
     Node = ExternalRuntime.new(
@@ -37,6 +39,7 @@ module ExecJS
     def self.runtimes
       @runtimes ||= [
         RubyRacer,
+        Mustang,
         RubyRhino,
         Node,
         JavaScriptCore,

test/test_runtimes.rb

@@ -57,6 +57,7 @@ module TestRuntime
 end
 
 runtimes = [
+  "Mustang",
   "RubyRacer",
   "RubyRhino",
   "Node",