gistfile1.rb

class Show < ActiveRecord::Base
  attr_accessible :artist_tokens, :cost, :booking_url, :door_charge, :venue_id, :date, :time, :starts_at
  attr_reader :artist_tokens, :date, :time

  validate :is_time
  validate :is_date
  before_save :save_date_and_time

  has_many :performances
  has_many :artists, :through => :performances
  belongs_to :user
  belongs_to :venue

  def artist_tokens=(tokens)
    self.artist_ids = Artist.ids_from_tokens(tokens)
  end

  def date
    if @date
      @date
    else
      starts_at ? starts_at.in_time_zone(Venue.get_venue_timezone(self.venue_id)).strftime("%A, %B #{starts_at.day.ordinalize}") : ""
    end
  end

  def date=(d)
    @date = d
  end

  def time
    if @time
      @time
    else
      starts_at ? starts_at.in_time_zone(Venue.get_venue_timezone(self.venue_id)).strftime("%l:%M %p") : ""
    end
  end

  def time=(t)
    @time = t
  end
    
private

  def is_time
    errors.add(:time, 'must be a valid time') if ((DateTime.parse(@time) rescue ArgumentError) == ArgumentError)
  end

  def is_date
    errors.add(:date, 'must be a valid date') if ((DateTime.parse(@date) rescue ArgumentError) == ArgumentError)
  end
  
  def save_date_and_time
    time_zone = Venue.get_venue_timezone(venue_id)
    self.starts_at = ActiveSupport::TimeZone[time_zone].parse(@date + " " + @time)
  end

end

When is date called? On form render on on submit? I don't understand why it would be called on new?

date and time in the save_date_and_time instances are blank, which makes me think they are being pulled from the DB (via the above methods) rather than using form params?

Line 36 should probably use the instance variables, rather than the getter method:

starts_at = Chronic.parse(@date + @time)