date_select’s :discard_month and :discard_day choose different default days

Imported from Lighthouse. Original ticket at: http://rails.lighthouseapp.com/projects/8994/tickets/6589 Created by Edward Ocampo-Gooding - 2011-03-17 04:29:10 UTC

When setting :discard_day as an option in the date_select view helper, the default day chosen is the first of the month.

However, when setting :discard_month, and it implicitly sets :discard_day, the default day chosen is the current day instead of the first of the month.

Which behaviour is correct? Either way, that feels like a bug.