Week of January 29-February 4, 2012

Things are still moving along on the Rails 4 front, with a mix of tidying up and new features. Here are some of the commits that caught my eye last week.

• A whole mess of commits worked over some of the collection form helpers. Now collection_select and options_from_collection_for_select can take procs to evaluate their text and value in the current context, and there are new collection_check_boxes and collection_radio_buttons helpers. The easiest starting point is with f506c806 which documents the API changes.
• 8270e4a8 implements the null object pattern for Active Record relations. Post.none will return a relation containing no posts - which may seem daffy, but makes for much nicer chainable methods on your Active Record objects.
• b31eac56 replaces all for loops in the Rails source code with Enumerable#each. This should lead to considerably less confusion for new Rails developers.
• 336ff8a9 reworks the :dependent => :restrict construct for Active Record associations to deprecate raising an exception on violation.
• 66c04431 updates Rails' Unicode support from 6.0 to 6.1, making it pile of poo compatible.