Embed lambdas and procs into V8::Context

This adds the ability embed basic Ruby code blocks into a javascript
context and invoke it.

  cxt = V8::Context.new
  cxt['twice'] = lambda {|str| "#{str}#{str}"}
  cxt.eval('twice("hi")') #=> "hihi"

Note that error handling is not accounted for yet. If an exception
happens inside the called proc, it will cause terrible, awful things
to happen because portions of the C++ stack will not be unwound leaving
the Isolate in an indeterminate state.

lib/v8/conversion.rb

@@ -140,3 +140,28 @@ class Symbol
     V8::C::Symbol::For(context.isolate.native, V8::C::String::NewFromUtf8(isolate, to_s))
   end
 end
+
+class Object
+  def to_v8(context)
+    V8::C::Object::New(context.isolate.native)
+  end
+end
+
+class Proc
+  def to_v8(context)
+    isolate = context.isolate.native
+    callback = lambda do |info|
+      args = []
+      arity = info.Length()
+      if self.arity > -1
+        arity = self.arity
+      end
+      arity.times do |i|
+        args << context.to_ruby(info[i])
+      end
+      result = context.to_v8 self.call(*args)
+      info.GetReturnValue().Set(result)
+    end
+    V8::C::Function::New(isolate, callback)
+  end
+end

lib/v8/conversion/fundamental.rb

@@ -43,7 +43,18 @@ class V8::Conversion
     # First it checks to see if there is an entry in the id map for
     # this object. Otherwise, it will run the default conversion.
     def to_v8(context, ruby_object)
-      rb_idmap[ruby_object.object_id] || ruby_object.to_v8(context)
+      if v8_object = rb_idmap[ruby_object.object_id]
+        v8_object
+      else
+        v8_object = ruby_object.to_v8(context)
+        if v8_object.kind_of? V8::C::Object
+          v8_object.tap do
+            equate ruby_object, v8_object
+          end
+        else
+          v8_object
+        end
+      end
     end
 
     ##

spec/v8/context_spec.rb

@@ -93,12 +93,12 @@ describe "V8::Context" do
       end
     end
 
-    # xit "unwraps ruby objects returned by embedded ruby code to maintain referential integrity" do
+    it "unwraps ruby objects returned by embedded ruby code to maintain referential integrity" do
-    #   Object.new.tap do |o|
+      Object.new.tap do |o|
-    #     @cxt['get'] = lambda {o}
+        @cxt['get'] = lambda {o}
-    #     @cxt.eval('get()').should be(o)
+        @cxt.eval('get()').should be(o)
-    #   end
+      end
-    # end
+    end
 
     it "always returns the same ruby object for a single javascript object" do
       obj = @cxt.eval('obj = {}')
@@ -133,25 +133,25 @@ describe "V8::Context" do
     # end
   end
 
-#   describe "Calling Ruby Code From Within Javascript", :compat => '0.1.0' do
+  describe "Calling Ruby Code From Within Javascript" do
 
-#     before(:each) do
+     before(:each) do
 #       @class = Class.new
 #       @instance = @class.new
-#       @cxt = V8::Context.new
+       @cxt = V8::Context.new
 #       @cxt['o'] = @instance
-#     end
+     end
 
-#     xit "can embed a closure into a context and call it" do
+    it "can embed a closure into a context and call it" do
-#       @cxt["say"] = lambda { |*args| args[-2] * args[-1] }
+      @cxt["say"] = lambda { |*args| args[-2] * args[-1] }
-#       @cxt.eval("say('Hello', 2)").should == "HelloHello"
+      @cxt.eval("say('Hello', 2)").should == "HelloHello"
-#     end
+    end
 
-#     xit "recognizes the same closure embedded into the same context as the same function object" do
+    it "recognizes the same closure embedded into the same context as the same function object" do
-#       @cxt['say'] = @cxt['declare'] = lambda { |*args| args }
+      @cxt['say'] = @cxt['declare'] = lambda { |*args| args }
-#       @cxt.eval('say == declare').should be(true)
+      @cxt.eval('say == declare').should be(true)
-#       @cxt.eval('say === declare').should be(true)
+      @cxt.eval('say === declare').should be(true)
-#     end
+    end
 
 #     xit "translates ruby Array to Javascript Array" do
 #       class_eval do
@@ -275,17 +275,17 @@ describe "V8::Context" do
 #       @cxt.eval('typeof(RObject)').should == 'function'
 #     end
 
-#     xit "truncates lambda arguments passed in to match the arity of the function", :compat => '0.4.2' do
+    it "truncates lambda arguments passed in to match the arity of the function", :compat => '0.4.2' do
-#       @cxt['testing'] = lambda { |arg| arg }
+      @cxt['testing'] = lambda { |arg| arg }
-#       lambda {
+      lambda {
-#         @cxt.eval('testing(1,2,3)')
+        @cxt.eval('testing(1,2,3)')
-#       }.should_not raise_error
+      }.should_not raise_error
 
-#       @cxt['testing'] = lambda { }
+      @cxt['testing'] = lambda { }
-#       lambda {
+      lambda {
-#         @cxt.eval('testing(1,2,3)')
+        @cxt.eval('testing(1,2,3)')
-#       }.should_not raise_error
+      }.should_not raise_error
-#     end
+    end
 
 #     xit "truncates method arguments passed in to match the arity of the function", :compat => '0.4.3' do
 #       @instance.instance_eval do
@@ -652,7 +652,7 @@ describe "V8::Context" do
 #       @class.class_eval &body
 #     end
 
-#   end
+  end
 
    describe "Calling JavaScript Code From Within Ruby", :compat => '0.1.0' do