Issue with using polymorphic_path with FactoryGirl build object
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I am using factory_girl and rspec2 for my testing. I have an issue with the following code:

    let(:book) { build(:book, id: 1) }
    book_path(book)

book_path statement is generating **/books** url instead of **/books/1**. I can use create, but any suggestions on how to fix this using build strategy?

I am using 

    rspec-rails (2.11.0)
    factory_girl (3.5.0)