better object id representation for inspect

lib/bson/types/objectid.rb

@@ -22,6 +22,10 @@ require 'digest/md5'
 
 module BSON
 
+  def BSON::ObjectID(s)
+    ObjectID.from_string(s)
+  end
+
   # Generates MongoDB object ids.
   #
   # @core objectids
@@ -129,11 +133,11 @@ module BSON
     end
 
     def inspect
-      {"$oid" => to_s}
+      "BSON::ObjectID('#{to_s}')"
     end
 
     # Convert to MongoDB extended JSON format. Since JSON includes type information,
-    # but lacks an ObjectID type, this JSON format encodes the type using an $id key.
+    # but lacks an ObjectID type, this JSON format encodes the type using an $oid key.
     #
     # @return [String] the object id represented as MongoDB extended JSON.
     def to_json(escaped=false)

test/mongo_bson/objectid_test.rb

@@ -1,4 +1,6 @@
 require 'test/test_helper'
+require 'rubygems'
+require 'json'
 
 class ObjectIDTest < Test::Unit::TestCase
 
@@ -49,9 +51,12 @@ class ObjectIDTest < Test::Unit::TestCase
     assert_equal 24, $1.length
   end
 
+  def test_method
+    assert_equal ObjectID.from_string(@o.to_s), BSON::ObjectID(@o.to_s)
+  end
+
   def test_inspect
-    obj = {'$oid' => @o.to_s}
-    assert_equal obj, @o.inspect
+    assert_equal "BSON::ObjectID('#{@o.to_s}')", @o.inspect
   end
 
   def test_save_and_restore