What's New in Edge Rails #2

A lot of the activity over the past week went for removing Ruby 1.8.x support code from the Rails codebase. I'm not going to list out the dozens of commits from a bunch of contributors; suffice it to say that Rails, like many people I know, went on a sudden post-holiday diet.

Week of 12/25-31/2011

• Rails uses Rack 1.4.0 as of 0d01e09c6c78c2276433e69671af5c211e243d50. You should too - or else upgrade your older version of Rack to the latest point release to fix a security issue.
• With the extraction of ActiveRecord::Model into a module, there's a need to include configuration on those models. This is supplied in 93c1f11c0a5097a5431819a1551a02a869a16a38 as an ActiveRecord::Configuration module which provides a config_attribute macro - but this is not considered a public API, so use at your own risk.
• We're moving towards explicitly declaring which tables to eager load with an eager_load predicate, rather than trying to deduce them from other parts of an Active Record relation. c99d507fccca2e9e4d12e49b4387e007c5481ae9 has a chunk of work on this; Issue 950 is tracking overall progress.
• 8a130edb0f7b3aacf74d080d3da3b2d871f650d6 adds a second parameter, flush, to content_for. If this is set to true then the supplied block replaces any existing block rather than concatenating to it.