formatted_date_range.rb

  def formatted_date_range(start_date, end_date = nil)
    if start_date && end_date
      same_month = start_date.month == end_date.month
      same_year = start_date.year == end_date.year
      
      date = "#{start_date.strftime("%B %e")} - #{end_date.strftime("%e, %Y")}" if same_month && same_year
      date = "#{start_date.strftime("%B %e")} - #{end_date.strftime("%B %e, %Y")}" if !same_month && same_year
      date = "#{start_date.strftime("%B %e, %Y")} - #{end_date.strftime("%B %e, %Y")}" if !same_year
    else
      date = start_date.strftime("%A, %B %e, %Y")
    end
    date
  end

  # rspec tests
  describe "formatted date range" do
    it "should print just start date if no end date is provided" do
      start_date = Date.parse("January 01 2010")
      formatted_date_range(start_date).should match("Friday,\s+January\s+1,\s+2010")
    end
    it "should only show year once if start date has the same year as end date" do
      start_date = Date.parse("January 01 2010")
      end_date = start_date + 2.months
      formatted_date_range(start_date, end_date).should match("January\s+1\s+-\s+March\s+1,\s+2010")
    end
    it "should show years from both start and end date if the dates have different years" do
      start_date = Date.parse("January 01 2010")
      end_date = start_date + 2.years
      formatted_date_range(start_date, end_date).should match(/January\s+1,\s+2010\s+-\s+January\s+1,\s+2012/)
    end
    it "should only show month once if start date has the same month as end date" do
      start_date = Date.parse("January 01 2010")
      end_date = start_date + 3.days
      formatted_date_range(start_date, end_date).should match(/January\s+1\s+-\s+4,\s+2010/)
    end
    it "should show months from both start and end date if the dates have different months" do
      start_date = Date.parse("January 01 2010")
      end_date = start_date + 2.months
      formatted_date_range(start_date, end_date).should match(/January\s+1\s+-\s+March\s+1,\s+2010/)
    end
  end