fix double save missing error by using copy not actual reference

lib/concern/has_custom_fields.rb

@@ -14,6 +14,10 @@ module Concern
       end
     end
 
+    def custom_fields=(data)
+      custom_fields.replace(data)
+    end
+
     protected
 
     def save_custom_fields
@@ -24,7 +28,7 @@ module Concern
           if dup[f.name] != f.value
             f.destroy
           else
-            dup.remove[f.name]
+            dup.delete(f.name)
           end
         end
 
@@ -32,7 +36,7 @@ module Concern
           _custom_fields.create(name: k, value: v)
         end
 
-        @custom_fields_orig = @custom_fields
+        @custom_fields_orig = dup
       end
     end
   end

spec/components/concern/has_custom_fields_spec.rb

@@ -51,6 +51,20 @@ describe Concern::HasCustomFields do
       test_item.custom_fields.should == {"jack" => "jill"}
     end
 
+    it "double save actually saves" do
+
+      test_item = TestItem.new
+      test_item.custom_fields = {"a" => "b"}
+      test_item.save
+
+      test_item.custom_fields["c"] = "d"
+      test_item.save
+
+      db_item = TestItem.find(test_item.id)
+      db_item.custom_fields.should == {"a" => "b", "c" => "d"}
+
+    end
+
 
     it "simple modifications don't interfere" do
       test_item = TestItem.new