For those of you that are familiar with composed_of/aggregations, I've created a patch to address a small bug in the writer's behavior when the converter returns nil.
Currently the writer first checks for nil assignment, and only then does it set the mapped attributes to nil. If the assigned value is not nil, then it calls the converter and, finally, applies the mapping rules. The problem occurs when the converter returns nil: the mapping methods are invoked on nil.
My patch runs the converter first (BUT NOT with nil assignments) and then looks for nil values to decide to map or convert mapped attributes to nil.
I've created a nice test case which exercises the theoretical difference between to_s and to_str.
Reaction-provoking comment?: :allow_nil => false's behavior seems contrived now that we have all the goodness of :converter and :constructor. At a minimum, someone should consider making the default for :allow_nil be true. But I was too scared to add that to my patch.
Comments/votes welcome: #2747 Aggregation writer doesn't behave nicely when converter returns nil - Ruby on Rails - rails
