Using Merge Keys in Fixtures and Unique Identifier Error

I'm trying to use merge keys with a Rai开发者_运维百科ls YAML fixture. I have:

BOOK: &BOOK
  name: To Kill a Mocking Bird
  upc: 0215192786624

item_a:
  owner: user_a
  <<: *BOOK

item_b:
  owner: user_b
  <<: *BOOK

However, this causes Sqlite to complain on some of our development machines about duplicate identical primary keys. Any ideas? I checked and all computers are running 1.9.2 p180, and the problem happens only on about half our machines. Thanks.

I wonder if this is due to an issue with merge keys not working in ruby 1.9. More specifically the switch to the psych yaml parser:

http://redmine.ruby-lang.org/issues/show/4300

You would have to specify concrete ids on item_a and item_b.