rails/rails — pull request #4007 by exviva (2011-12-16 22:22:06+00:00)
Title: Fix expanding cache key for single element arrays

In short:
`expand_cache_key(element)` should not equal `expand_cache_key([element])`

This way a fragment cache key for an index page with only a single
element in the collection is different than a fragment cache for a
typical show page for that element.