SPMetal Generating Duplicate Classes

Question

SPMetal is creating duplicate entities when I attempt to generate code with the following conditions.

I have a custom content type [Person] that inherits from [Contact].

I have created a list instance named [Persons] and deployed it to the server.

When I run SPMetal with the following parameters.xml file I get two classes generated

[Parameters.xml]
<List Name="Persons">
  <ContentType Name="Person" Class="Person" />
</List>

[GeneratedCode.cs]
public partial class Person : Contact
public partial class Person0 : Person

Am I doing something wrong? Is there a way to simply generate one class per content type?

UPDATE:

I have determined that SPMetal is generating two classes: [Person] and [Person0] because Person is a content type but it's fields were copied to the list definition schema file when I used it in a list definition. I verified this by removing the content type, but leaving the list, SPMetal only generates one instance of the person class in this case.

Not sure where I'm going from here but wanted to update the question in case someone else was following along.

Answer 1

I had the same problem and it bugged me for a bit but I found the fix. Simply remove the contenty type you have inside the list:

It seems that the content type in the list definition is there to provide an annotated class in the case that your list content type has a name that you don't prefer. I can imagine this would have other implications though; like not being able to choose which columns to include from the content type your list is inheriting from.

In the example here: http://msdn.microsoft.com/en-us/library/ee539978.aspx

It mentions that it is simply used to rename the output class.

Answer 2

This behavior is "By-design" and it CAN'T be overriden even if you want to. This is documented in MSDN at:

http://msdn.microsoft.com/en-us/library/ee537010.aspx

*Rules below that are marked with an asterisk cannot be overridden.

6.If a content type inherits from another content type, then the generated class that represents the former inherits from the class that represents the latter.