all the little things (rubyonales)

@sandimetz Mar 2014 sandi metz all the little things Friday,
March 7, 14

@sandimetz Mar 2014 Want better apps? Friday, March 7, 14

@sandimetz Mar 2014 make smaller things Friday, March 7, 14

@sandimetz Mar 2014 The Gilded Rose Kata Friday, March 7,
14

@sandimetz Mar 2014 class GildedRose attr_reader :name, :quality, :days_remaining
def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick # ... end end Friday, March 7, 14

@sandimetz Mar 2014 def tick if
@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end # 21 more lines def tick if name != 'Aged Brie' && name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if quality < 50 @quality += 1 if name == 'Backstage passes to a TAFKAL80ETC concert' if days_remaining < 11 if quality < 50 @quality += 1 end end if days_remaining < 6 if quality < 50 @quality += 1 end end end end end if name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if days_remaining < 0 if name != "Aged Brie" if name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = quality -‐ quality end else if quality < 50 @quality += 1 end end end end end Friday, March 7, 14

@sandimetz Mar 2014 def tick #
22 previous lines if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end def tick if name != 'Aged Brie' && name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if quality < 50 @quality += 1 if name == 'Backstage passes to a TAFKAL80ETC concert' if days_remaining < 11 if quality < 50 @quality += 1 end end if days_remaining < 6 if quality < 50 @quality += 1 end end end end end if name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if days_remaining < 0 if name != "Aged Brie" if name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = quality -‐ quality end else if quality < 50 @quality += 1 end end end end end Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 44.7 0 25 50 big conditional Complexity (Flog) Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 44.7 0 25 50 big conditional Complexity (Flog) 50 Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 44.7 0 25 50 big conditional Complexity (Flog) 45 tick 50 Friday, March 7, 14

@sandimetz Mar 2014 Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end Squint Test Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end changes in shape Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 2 Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end changes in color Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 16 if statements Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 16 if statements 7 != Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 16 if statements 7 != 2 != with && Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 16 if statements 7 != 2 != with && 3 magic strings Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end 16 if statements 7 != 2 != with && 3 magic strings ? magic numbers Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end magic strings Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end ‘Aged Brie’ magic strings Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end ‘Aged Brie’ ‘Sulfuras, Hand of Ragnaros’ magic strings Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end ‘Aged Brie’ ‘Sulfuras, Hand of Ragnaros’ ‘Backstage passes to a TAFKAL80ETC concert’ magic strings Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end it has tests Friday, March 7, 14

@sandimetz Mar 2014 # Running: S..S.S...S..........S....S..... Fabulous run in 0.002800s,
11071.4286 runs/s, 17857.1429 assertions/s. 31 runs, 50 assertions, 0 failures, 0 errors, 6 skips Friday, March 7, 14

@sandimetz Mar 2014 class GildedRoseTest < Minitest::Test def test_normal_item_before_sell_date
def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound def test_backstage_pass_very_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_lower_bound def test_backstage_pass_very_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_on_sell_date def test_backstage_pass_after_sell_date Friday, March 7, 14

def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound def test_backstage_pass_very_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_lower_bound def test_backstage_pass_very_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_on_sell_date def test_backstage_pass_after_sell_date brie Friday, March 7, 14

def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound def test_backstage_pass_very_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_lower_bound def test_backstage_pass_very_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_on_sell_date def test_backstage_pass_after_sell_date brie sulfuras Friday, March 7, 14

def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound def test_backstage_pass_very_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_lower_bound def test_backstage_pass_very_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_on_sell_date def test_backstage_pass_after_sell_date brie sulfuras backstage pass Friday, March 7, 14

def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound def test_backstage_pass_very_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_lower_bound def test_backstage_pass_very_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_on_sell_date def test_backstage_pass_after_sell_date brie sulfuras backstage pass normal Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound let’s look at a test Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound name Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound name quality Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound name quality days_remaining Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound Friday, March 7, 14

item = GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound reduced by 1 Friday, March 7, 14

@sandimetz Mar 2014 class GildedRoseTest < Minitest::Test def test_conjured_item_before_sell_date
def test_conjured_item_at_zero_quality def test_conjured_item_on_sell_date def test_conjured_item_on_sell_date_at_zero_quality def test_conjured_item_after_sell_date def test_conjured_item_after_sell_date_at_zero_quality end Friday, March 7, 14

def test_conjured_item_at_zero_quality def test_conjured_item_on_sell_date def test_conjured_item_on_sell_date_at_zero_quality def test_conjured_item_after_sell_date def test_conjured_item_after_sell_date_at_zero_quality end 6 skipped tests Friday, March 7, 14

@sandimetz Mar 2014 Task: Friday, March 7, 14

@sandimetz Mar 2014 Task: Implement Conjured Friday, March 7, 14

def test_conjured_item_at_zero_quality def test_conjured_item_on_sell_date def test_conjured_item_on_sell_date_at_zero_quality def test_conjured_item_after_sell_date def test_conjured_item_after_sell_date_at_zero_quality end I tried Friday, March 7, 14

def test_conjured_item_at_zero_quality def test_conjured_item_on_sell_date def test_conjured_item_on_sell_date_at_zero_quality def test_conjured_item_after_sell_date def test_conjured_item_after_sell_date_at_zero_quality end but failed Friday, March 7, 14

def test_conjured_item_at_zero_quality def test_conjured_item_on_sell_date def test_conjured_item_on_sell_date_at_zero_quality def test_conjured_item_after_sell_date def test_conjured_item_after_sell_date_at_zero_quality end miserably Friday, March 7, 14

@sandimetz Mar 2014 the pattern failed me Friday, March 7,
14

@sandimetz Mar 2014 Task: Friday, March 7, 14

@sandimetz Mar 2014 Task: Refactor code so I can Implement
Conjured Friday, March 7, 14

def test_normal_item_on_sell_date def test_normal_item_after_sell_date def test_normal_item_of_zero_quality normal Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end # .... def tick if name != 'Aged Brie' && name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if quality < 50 @quality += 1 if name == 'Backstage passes to a TAFKAL80ETC concert' if days_remaining < 11 if quality < 50 @quality += 1 end end if days_remaining < 6 if quality < 50 @quality += 1 end end end end end if name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if days_remaining < 0 if name != "Aged Brie" if name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = quality -‐ quality end else if quality < 50 @quality += 1 end end end end end Friday, March 7, 14

@name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end def tick if name == 'normal' return end if name != 'Aged Brie' && name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if quality < 50 @quality += 1 if name == 'Backstage passes to a TAFKAL80ETC concert' if days_remaining < 11 if quality < 50 @quality += 1 end end if days_remaining < 6 if quality < 50 @quality += 1 end end end end end if name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if days_remaining < 0 if name != "Aged Brie" if name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = quality -‐ quality end else if quality < 50 @quality += 1 end end end end end Friday, March 7, 14

name == 'normal' return end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end def tick if name == 'normal' return end if name != 'Aged Brie' && name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if quality < 50 @quality += 1 if name == 'Backstage passes to a TAFKAL80ETC concert' if days_remaining < 11 if quality < 50 @quality += 1 end end if days_remaining < 6 if quality < 50 @quality += 1 end end end end end if name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if days_remaining < 0 if name != "Aged Brie" if name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = quality -‐ quality end else if quality < 50 @quality += 1 end end end end end Friday, March 7, 14

@sandimetz Mar 2014 # Running: .S...S...S..SFF....F.....SS.F.. Fabulous run in 0.020340s,
1524.0905 runs/s, 2310.7178 assertions/s. 1) Failure: GildedRoseTest#test_normal_item_of_zero_quality [gilded_rose_test.rb:37]: Expected: 4 Actual: 5 2) Failure: GildedRoseTest#test_normal_item_before_sell_date [gilded_rose_test.rb:12]: Expected: 9 Actual: 10 3) Failure: GildedRoseTest#test_normal_item_on_sell_date [gilded_rose_test.rb:20]: Expected: 8 Actual: 10 4) Failure: GildedRoseTest#test_normal_item_after_sell_date [gilded_rose_test.rb:28]: Expected: 8 Actual: 10 31 runs, 47 assertions, 4 failures, 0 errors, 6 skips Friday, March 7, 14

1524.0905 runs/s, 2310.7178 assertions/s. 1) Failure: GildedRoseTest#test_normal_item_of_zero_quality [gilded_rose_test.rb:37]: Expected: 4 Actual: 5 2) Failure: GildedRoseTest#test_normal_item_before_sell_date [gilded_rose_test.rb:12]: Expected: 9 Actual: 10 3) Failure: GildedRoseTest#test_normal_item_on_sell_date [gilded_rose_test.rb:20]: Expected: 8 Actual: 10 4) Failure: GildedRoseTest#test_normal_item_after_sell_date [gilded_rose_test.rb:28]: Expected: 8 Actual: 10 31 runs, 47 assertions, 4 failures, 0 errors, 6 skips 4 failures Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def tick
if name == 'normal' return end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end end Friday, March 7, 14

if name == 'normal' return end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end def normal_tick end end Friday, March 7, 14

if name == 'normal' return normal_tick end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end def normal_tick end end Friday, March 7, 14

1524.0905 runs/s, 2310.7178 assertions/s. 1) Failure: GildedRoseTest#test_normal_item_of_zero_quality [gilded_rose_test.rb:37]: Expected: 4 Actual: 5 2) Failure: GildedRoseTest#test_normal_item_before_sell_date [gilded_rose_test.rb:12]: Expected: 9 Actual: 10 3) Failure: GildedRoseTest#test_normal_item_on_sell_date [gilded_rose_test.rb:20]: Expected: 8 Actual: 10 4) Failure: GildedRoseTest#test_normal_item_after_sell_date [gilded_rose_test.rb:28]: Expected: 8 Actual: 10 31 runs, 47 assertions, 4 failures, 0 errors, 6 skips 4 failures Friday, March 7, 14

@sandimetz Mar 2014 def test_normal_item_before_sell_date item
= GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end Friday, March 7, 14

= GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end class GildedRose # ... def normal_tick end end Friday, March 7, 14

= GildedRose.new('normal', 10, 5) item.tick assert_equal 9, item.quality assert_equal 4, item.days_remaining end class GildedRose # ... def normal_tick @quality -‐= 1 @days_remaining -‐= 1 end end Friday, March 7, 14

@sandimetz Mar 2014 # Running: .....S...FS....FS.S...FS....S.. Fabulous run in 0.029178s,
1062.4443 runs/s, 1713.6199 assertions/s. 1) Failure: GildedRoseTest#test_normal_item_of_zero_quality [gilded_rose_test.rb:38]: Expected: 0 Actual: -‐1 2) Failure: GildedRoseTest#test_normal_item_after_sell_date [gilded_rose_test.rb:30]: Expected: 8 Actual: 9 3) Failure: GildedRoseTest#test_normal_item_on_sell_date [gilded_rose_test.rb:22]: Expected: 8 Actual: 9 31 runs, 50 assertions, 3 failures, 0 errors, 6 skips 3 failures Friday, March 7, 14

@sandimetz Mar 2014 def test_normal_item_on_sell_date item
= GildedRose.new('normal', 10, 0) item.tick assert_equal 8, item.quality assert_equal -‐1, item.days_remaining end class GildedRose # ... def normal_tick @quality -‐= 1 @days_remaining -‐= 1 end end Friday, March 7, 14

= GildedRose.new('normal', 10, 0) item.tick assert_equal 8, item.quality assert_equal -‐1, item.days_remaining end class GildedRose # ... def normal_tick if @days_remaining > 0 @quality -‐= 1 end @days_remaining -‐= 1 end end Friday, March 7, 14

= GildedRose.new('normal', 10, 0) item.tick assert_equal 8, item.quality assert_equal -‐1, item.days_remaining end class GildedRose # ... def normal_tick if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end @days_remaining -‐= 1 end end Friday, March 7, 14

@sandimetz Mar 2014 # Running: ...S.S.....S..S..SF.....S...... Fabulous run in 0.019924s,
1555.9125 runs/s, 2459.3455 assertions/s. 1) Failure: GildedRoseTest#test_normal_item_of_zero_quality [gilded_rose_test.rb:37]: Expected: 0 Actual: -‐1 31 runs, 49 assertions, 1 failures, 0 errors, 6 skips 1 failure ?? Friday, March 7, 14

@sandimetz Mar 2014 def test_normal_item_of_zero_quality item
= GildedRose.new('normal', 0, 5) item.tick assert_equal 0, item.quality assert_equal 4, item.days_remaining end class GildedRose # ... def normal_tick if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end @days_remaining -‐= 1 end end Friday, March 7, 14

@sandimetz Mar 2014 def test_normal_item_of_zero_quality item
= GildedRose.new('normal', 0, 5) item.tick assert_equal 0, item.quality assert_equal 4, item.days_remaining end class GildedRose # ... def normal_tick if @quality != 0 if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end @days_remaining -‐= 1 end end Friday, March 7, 14

@sandimetz Mar 2014 refactor under green Friday, March 7, 14

@sandimetz Mar 2014 def normal_tick if
@quality != 0 if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end @days_remaining -‐= 1 end Friday, March 7, 14

@sandimetz Mar 2014 def normal_tick end def
normal_tick if @quality != 0 if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end @days_remaining -‐= 1 end Friday, March 7, 14

@sandimetz Mar 2014 def normal_tick @days_remaining
-‐= 1 end def normal_tick if @quality != 0 if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end @days_remaining -‐= 1 end Friday, March 7, 14

-‐= 1 end def normal_tick if @quality != 0 if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end end Friday, March 7, 14

-‐= 1 return if @quality == 0 end def normal_tick if @quality != 0 if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end end Friday, March 7, 14

-‐= 1 return if @quality == 0 end def normal_tick if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 end def normal_tick if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def normal_tick if @days_remaining > 0 @quality -‐= 1 end if @days_remaining <= 0 @quality -‐= 2 end end Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def normal_tick end Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end Friday, March 7, 14

if name == 'normal' return normal_tick end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end end Reprise Friday, March 7, 14

if name == 'normal' return normal_tick end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end end Friday, March 7, 14

if name == 'normal' return normal_tick end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

if name == 'normal' return normal_tick end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' # ... 40 more lines end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end normal Friday, March 7, 14

@sandimetz Mar 2014 class GildedRoseTest < Minitest::Test # def test_normal
... etc def test_brie_before_sell_date def test_brie_before_sell_date_with_max_quality def test_brie_on_sell_date def test_brie_on_sell_date_near_max_quality def test_brie_on_sell_date_with_max_quality def test_brie_after_sell_date def test_brie_after_sell_date_with_max_quality # def test_sulfuras ... etc # def test_backstage ... etc end brie Friday, March 7, 14

@sandimetz Mar 2014 def tick if name
== 'normal' return normal_tick end # ... end Friday, March 7, 14

@sandimetz Mar 2014 def tick case
name when 'normal' return normal_tick end # ... end Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick end # ... end Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick end # ... end def brie_tick end Friday, March 7, 14

@sandimetz Mar 2014 # Running: .F...F.....S.S.F..S.FF.S.F.FS.S Fabulous run in 0.027410s,
1130.9741 runs/s, 1678.2196 assertions/s. 1) Failure: GildedRoseTest#test_brie_on_sell_date_with_max_quality [gilded_rose_test.rb:78]: Expected: 4 Actual: 5 2) Failure: GildedRoseTest#test_brie_on_sell_date_near_max_quality [gilded_rose_test.rb:69]: Expected: 50 Actual: 49 3) Failure: GildedRoseTest#test_brie_on_sell_date [gilded_rose_test.rb:61]: Expected: 12 Actual: 10 4) Failure: GildedRoseTest#test_brie_after_sell_date_with_max_quality [gilded_rose_test.rb:94]: Expected: -‐11 Actual: -‐10 5) Failure: GildedRoseTest#test_brie_before_sell_date_with_max_quality [gilded_rose_test.rb:54]: Expected: 6 Actual: 7 7 failures Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick end # ... end def brie_tick end Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick end # ... end def brie_tick end fast forward... Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick end # ... end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick end # ... end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end brie Friday, March 7, 14

@sandimetz Mar 2014 # Running: ...S......S.....SS.....SS...... Fabulous run in 0.003862s,

@sandimetz Mar 2014 def normal_tick @days_remaining -‐=
1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end Similarity Friday, March 7, 14

@sandimetz Mar 2014 def normal_tick @days_remaining -‐=
1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end Friday, March 7, 14

@sandimetz Mar 2014 duplication is far cheaper than the wrong
abstraction Friday, March 7, 14

... etc # def test_brie ... etc def test_sulfuras_before_sell_date def test_sulfuras_on_sell_date def test_sulfuras_after_sell_date # def test_backstage ... etc end sulfuras Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick when 'Sulfuras, Hand of Ragnaros' return sulfuras_tick end # ... end def sulfuras_tick end Friday, March 7, 14

8026.9291 runs/s, 12946.6598 assertions/s. 31 runs, 50 assertions, 0 failures, 0 errors, 6 skips 0 failures ?!? Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick when 'Sulfuras, Hand of Ragnaros' return sulfuras_tick end # ... end def sulfuras_tick end Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick when 'Sulfuras, Hand of Ragnaros' return sulfuras_tick end # ... end def sulfuras_tick end nothing changes Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick when 'Sulfuras, Hand of Ragnaros' return sulfuras_tick end # ... end def sulfuras_tick end sulfuras Friday, March 7, 14

... etc # def test_brie ... etc # def test_sulfuras ... etc def test_backstage_pass_long_before_sell_date def test_backstage_pass_medium_close_to_sell_date_upper_bound def test_backstage_pass_medium_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_medium_close_to_sell_date_lower_bound def test_backstage_pass_medium_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_upper_bound def test_backstage_pass_very_close_to_sell_date_upper_bound_at_max_quality def test_backstage_pass_very_close_to_sell_date_lower_bound def test_backstage_pass_very_close_to_sell_date_lower_bound_at_max_quality def test_backstage_pass_on_sell_date def test_backstage_pass_after_sell_date end backstage Friday, March 7, 14

name when 'normal' when 'Aged Brie' when 'Sulfuras, Hand of Ragnaros' when 'Backstage passes to a TAFKAL80ETC concert' return backstage_tick end # ... end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end backstage Friday, March 7, 14

name when 'normal' return normal_tick when 'Aged Brie' return brie_tick when 'Sulfuras, Hand of Ragnaros' return sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' return backstage_tick end if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC c # ... end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick def sulfuras_tick def backstage_tick class GildedRose attr_reader :name, :quality, :days_remaining def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remai end def tick case name when 'normal' return normal_tick when 'Aged Brie' return brie_tick when 'Sulfuras, Hand of Ragnaros' return sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' return backstage_tick end if name != 'Aged Brie' && name != 'Backstage passes to a TAF if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if quality < 50 @quality += 1 if name == 'Backstage passes to a TAFKAL80ETC concert' if days_remaining < 11 if quality < 50 @quality += 1 end end if days_remaining < 6 if quality < 50 @quality += 1 end end end end end if name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if days_remaining < 0 if name != "Aged Brie" if name != 'Backstage passes to a TAFKAL80ETC concert' if quality > 0 if name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = quality -‐ quality end else if quality < 50 @quality += 1 end end end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end Friday, March 7, 14

@sandimetz Mar 2014 small methods are simple Friday, March 7,
14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end small methods Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end class GildedRose attr_reader :name, :quality, :days_remaining def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end end big conditional small methods Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 25 50 big conditional Total Complexity 50 Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 25 50 big conditional small methods tick normal brie backstage other 40 Total Complexity 50 Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 25 50 big conditional small methods tick normal brie backstage other 12 40 45 Total Complexity 50 Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end Complexity 50 big conditional Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 45 90 Complexity 50 big conditional Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 45 90 Complexity 50 84 40 small methods big conditional 10 Refactorings Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick def brie_tick Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick def brie_tick def sulfuras_tick Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick def brie_tick def sulfuras_tick def backstage_tick Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick def brie_tick def sulfuras_tick def backstage_tick def conjured_tick Friday, March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick def brie_tick def sulfuras_tick def backstage_tick def conjured_tick ??? Friday, March 7, 14

@sandimetz Mar 2014 the pattern still fails me Friday, March
7, 14

@sandimetz Mar 2014 open / closed Friday, March 7, 14

@sandimetz Mar 2014 open for extension Friday, March 7, 14

@sandimetz Mar 2014 open for extension closed for modiﬁcation Friday,
March 7, 14

-‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end def normal_tick def brie_tick def sulfuras_tick def backstage_tick Friday, March 7, 14

@sandimetz Mar 2014 they’re screaming to get out Friday, March
7, 14

@sandimetz Mar 2014 GildedRose Friday, March 7, 14

@sandimetz Mar 2014 brie_tick backstage_tick sulfuras_tick normal_tick GildedRose Friday, March
7, 14

@sandimetz Mar 2014 Normal brie_tick backstage_tick sulfuras_tick normal_tick GildedRose Friday,
March 7, 14

@sandimetz Mar 2014 tick Normal brie_tick backstage_tick sulfuras_tick normal_tick GildedRose
Friday, March 7, 14

@sandimetz Mar 2014 tick Normal brie_tick backstage_tick sulfuras_tick GildedRose Friday,
March 7, 14

@sandimetz Mar 2014 tick Normal GildedRose brie_tick backstage_tick sulfuras_tick Friday,
March 7, 14

@sandimetz Mar 2014 def normal_tick
@days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end Friday, March 7, 14

@sandimetz Mar 2014 def tick
@days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end Friday, March 7, 14

@sandimetz Mar 2014 class Normal def
tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 class Normal def
initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 class Normal attr_reader
:quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 class Normal
attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def normal_tick
end class Normal attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) end class Normal attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end class Normal attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 tick Normal GildedRose brie_tick backstage_tick sulfuras_tick Friday,
March 7, 14

@sandimetz Mar 2014 normal is an object Friday, March 7,
14

@sandimetz Mar 2014 brie/sulfuras/backstage are not Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def quality end def days_remaining end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def quality return item.quality if item end def days_remaining end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def quality return item.quality if item @quality end def days_remaining end Friday, March 7, 14

@item = Normal.new(quality, days_remaining) item.tick end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def quality return item.quality if item @quality end def days_remaining return item.days_remaining if item @days_remaining end Friday, March 7, 14

@sandimetz Mar 2014 brie Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def brie_tick
@days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end Friday, March 7, 14

@days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end class Brie end Friday, March 7, 14

@days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end class Brie def tick end end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def brie_tick end
class Brie def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def brie_tick end
class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end Friday, March 7, 14

@item = Brie.new(quality, days_remaining) item.tick end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end Friday, March 7, 14

@sandimetz Mar 2014 sulfuras Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def sulfuras_tick end
Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def sulfuras_tick end
class Sulfuras attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def sulfuras_tick
@item = Sulfuras.new(quality, days_remaining) item.tick end class Sulfuras attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end Friday, March 7, 14

@sandimetz Mar 2014 backstage Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def backstage_tick
@days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end Friday, March 7, 14

@days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end class Backstage def tick end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def backstage_tick end
class Backstage def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose def backstage_tick end
class Backstage attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end Friday, March 7, 14

@item = Backstage.new(quality, days_remaining) item.tick end class Backstage attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end Friday, March 7, 14

@sandimetz Mar 2014 normal/brie/sulfuras/backstage are now objects Friday, March 7,
14

@sandimetz Mar 2014 GildedRose tick Normal tick Brie tick Sulfuras
attr_reader :item tick Backstage attr_reader :quality, :days_remaining Friday, March 7, 14

case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @item = Normal.new(quality, days_remaining) item.tick end def brie_tick @item = Brie.new(quality, days_remaining) item.tick end # etc Friday, March 7, 14

@sandimetz Mar 2014 rewind Friday, March 7, 14

case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @item = Normal.new(quality, days_remaining) item.tick end def brie_tick @item = Brie.new(quality, days_remaining) item.tick end # etc Friday, March 7, 14

case name when 'normal' when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @item = Normal.new(quality, days_remaining) item.tick end def brie_tick @item = Brie.new(quality, days_remaining) item.tick end # etc Friday, March 7, 14

case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick end def brie_tick @item = Brie.new(quality, days_remaining) item.tick end # etc Friday, March 7, 14

case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def brie_tick @item = Brie.new(quality, days_remaining) item.tick end # etc Friday, March 7, 14

case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' when 'Sulfuras, Hand of Ragnaros' when 'Backstage passes to a TAFKAL80ETC concert' end end def brie_tick @item = Brie.new(quality, days_remaining) item.tick end # etc Friday, March 7, 14

case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' @item = Brie.new(quality, days_remaining) item.tick when 'Sulfuras, Hand of Ragnaros' @item = Sulfuras.new(quality, days_remaining) item.tick when 'Backstage passes to a TAFKAL80ETC concert' @item = Backstage.new(quality, days_remaining) item.tick end end Friday, March 7, 14

@sandimetz Mar 2014 abstract away the duplication Friday, March 7,
14

case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' @item = Brie.new(quality, days_remaining) item.tick when 'Sulfuras, Hand of Ragnaros' @item = Sulfuras.new(quality, days_remaining) item.tick when 'Backstage passes to a TAFKAL80ETC concert' @item = Backstage.new(quality, days_remaining) item.tick end end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose attr_reader :name, :item
def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' @item = Brie.new(quality, days_remaining) item.tick when 'Sulfuras, Hand of Ragnaros' @item = Sulfuras.new(quality, days_remaining) item.tick when 'Backstage passes to a TAFKAL80ETC concert' @item = Backstage.new(quality, days_remaining) item.tick end end Friday, March 7, 14

def initialize(name, quality, days_remaining) @item = ??? end def tick case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' @item = Brie.new(quality, days_remaining) item.tick when 'Sulfuras, Hand of Ragnaros' @item = Sulfuras.new(quality, days_remaining) item.tick when 'Backstage passes to a TAFKAL80ETC concert' @item = Backstage.new(quality, days_remaining) item.tick end end Friday, March 7, 14

def initialize(name, quality, days_remaining) @item = ???.new(quality, days_remaining) end def tick case name when 'normal' @item = Normal.new(quality, days_remaining) item.tick when 'Aged Brie' @item = Brie.new(quality, days_remaining) item.tick when 'Sulfuras, Hand of Ragnaros' @item = Sulfuras.new(quality, days_remaining) item.tick when 'Backstage passes to a TAFKAL80ETC concert' @item = Backstage.new(quality, days_remaining) item.tick end end Friday, March 7, 14

def initialize(name, quality, days_remaining) @item = ???.new(quality, days_remaining) end def case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Sulfuras when 'Backstage passes to a TAFKAL80ETC concert' Backstage end Friday, March 7, 14

def initialize(name, quality, days_remaining) @item = ???.new(quality, days_remaining) end def case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Sulfuras when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

def initialize(name, quality, days_remaining) @item = ???.new(quality, days_remaining) end def klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Sulfuras when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

def initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Sulfuras when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

@sandimetz Mar 2014 class GildedRose attr_reader :item def
initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Sulfuras when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end Friday, March 7, 14

initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end def tick item.tick end Friday, March 7, 14

initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end def tick item.tick end def quality return item.quality if item @quality end def days_remaining return item.days_remaining if item @days_remaining end Friday, March 7, 14

initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end def tick item.tick end def quality return item.quality if item end def days_remaining return item.days_remaining if item end Friday, March 7, 14

initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end Friday, March 7, 14

initialize(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

@sandimetz Mar 2014 item is a role Friday, March 7,
14

@sandimetz Mar 2014 GildedRose tick Normal tick Brie tick Sulfuras
attr_reader :item tick Backstage attr_reader :quality, :days_remaining Friday, March 7, 14

@sandimetz Mar 2014 attr_reader :item GildedRose ItemRole def tick
def quality def days_remaining Friday, March 7, 14

@sandimetz Mar 2014 attr_reader :item ItemRole def tick def
quality def days_remaining GildedRose Friday, March 7, 14

@sandimetz Mar 2014 attr_reader :item def tick end def quality
end def days_remaining end ItemRole def tick def quality def days_remaining GildedRose Friday, March 7, 14

@sandimetz Mar 2014 attr_reader :item def tick item.tick end
def quality item.quality end def days_remaining item.days_remaining end GildedRose ItemRole def tick def quality def days_remaining Friday, March 7, 14

@sandimetz Mar 2014 Foo def tick item.tick end def
quality item.quality end def days_remaining item.days_remaining end attr_reader :item GildedRose ItemRole def tick def quality def days_remaining Friday, March 7, 14

quality item.quality end def days_remaining item.days_remaining end attr_reader :item attr_reader :rose GildedRose ItemRole def tick def quality def days_remaining Friday, March 7, 14

quality item.quality end def days_remaining item.days_remaining end attr_reader :item attr_reader :rose def doit rose.tick rose.quality rose.days_remaining end GildedRose ItemRole def tick def quality def days_remaining Friday, March 7, 14

quality item.quality end def days_remaining item.days_remaining end attr_reader :item attr_reader :rose def doit rose.tick rose.quality rose.days_remaining end GildedRose ItemRole def tick def quality def days_remaining Middleman Friday, March 7, 14

@sandimetz Mar 2014 Foo attr_reader :item attr_reader :rose GildedRose ItemRole
def tick def quality def days_remaining Friday, March 7, 14

@sandimetz Mar 2014 Foo attr_reader :item attr_reader :rose def getit
@rose = GildedRose.new( ‘normal’, ...) end GildedRose ItemRole def tick def quality def days_remaining Friday, March 7, 14

@sandimetz Mar 2014 Foo def initialize(name,...) @item =
klass_for(name). new( quality, days_remaining) end def klass_for(name) case name when 'normal' Normal attr_reader :item attr_reader :rose def getit @rose = GildedRose.new( ‘normal’, ...) end GildedRose ItemRole def tick def quality def days_remaining Friday, March 7, 14

@sandimetz Mar 2014 Foo def initialize(name,...) @item =
klass_for(name). new( quality, days_remaining) end def klass_for(name) case name when 'normal' Normal attr_reader :item attr_reader :rose def getit @rose = GildedRose.new( ‘normal’, ...) end GildedRose ItemRole def tick def quality def days_remaining Item Factory Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose attr_reader :item def

self.for(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

self.for(name, quality, days_remaining) @item = klass_for(name).new(quality, days_remaining) end def self.klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

self.for(name, quality, days_remaining) klass_for(name).new(quality, days_remaining) end def self.klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose def self.for(name, quality, days_remaining)
klass_for(name).new(quality, days_remaining) end def self.klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

klass_for(name).new(quality, days_remaining) end def self.klass_for(name) # ... end def tick item.tick end def quality item.quality end def days_remaining item.days_remaining end class Normal class Brie class Sulfuras class Backstage end Middleman Friday, March 7, 14

klass_for(name).new(quality, days_remaining) end def self.klass_for(name) # ... end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

@sandimetz Mar 2014 Foo def self.for(name,...) end attr_reader :rose def
getit @rose = GildedRose.for( ‘normal’, ...) end GildedRose Friday, March 7, 14

@sandimetz Mar 2014 Foo attr_reader :rose def getit @rose
= GildedRose.for( ‘normal’, ...) end ItemRole def tick def quality def days_remaining def self.for(name,...) end GildedRose Friday, March 7, 14

@sandimetz Mar 2014 extract common code Friday, March 7, 14

klass_for(name).new(quality, days_remaining) end def self.klass_for(name) # ... end class Normal class Brie class Sulfuras class Backstage end Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose class Normal
attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose class Item end
class Normal attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose class Item
attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal def tick # ... end end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick # ... end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end class Sulfuras < Item def tick end end class Backstage < Item def tick Friday, March 7, 14

@sandimetz Mar 2014 inheritance is not evil Friday, March 7,
14

@sandimetz Mar 2014 but programmers sometimes are Friday, March 7,
14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end class Sulfuras < Item def tick end end class Backstage < Item def tick Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end class Sulfuras < Item def tick end end class Backstage < Item def tick Item quality days_remaining Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end class Sulfuras < Item def tick end end class Backstage < Item def tick Item quality days_remaining Normal Brie Sulfuras Backstage quality days_remaining tick Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end class Sulfuras < Item def tick end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick # ... end end class Brie < Item def tick # ... end end class Sulfuras < Item def tick end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Sulfuras < Item def tick end end Friday, March 7, 14

def tick end end class Sulfuras < Item def tick end end Friday, March 7, 14

def tick end end class Sulfuras < Item def tick end end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Sulfuras when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

def tick end end class Sulfuras < Item def tick end end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Item when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

def tick end end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Item when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end Friday, March 7, 14

@sandimetz Mar 2014 extract conﬁguration Friday, March 7, 14

klass_for(name).new(quality, days_remaining) end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Item when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end end Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose DEFAULT_CLASS = Item
SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) klass_for(name).new(quality, days_remaining) end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Item when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end end Friday, March 7, 14

SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) klass_for(name). new(quality, days_remaining) end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Item when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end end Friday, March 7, 14

SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS). new(quality, days_remaining) end def self.klass_for(name) case name when 'normal' Normal when 'Aged Brie' Brie when 'Sulfuras, Hand of Ragnaros' Item when 'Backstage passes to a TAFKAL80ETC concert' Backstage end end end Friday, March 7, 14

SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS). new(quality, days_remaining) end end Friday, March 7, 14

@sandimetz Mar 2014 small objects Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end module GildedRose class Item attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, end end Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose class Brie < Item
def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end module GildedRose class Item attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, end end Friday, March 7, 14

SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS). new(quality, days_remaining) end end module GildedRose class Item attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, end end Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remainin end end small objects Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remainin end end small objects class GildedRose attr_reader :name, :quality, :days_remaining def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick if @name != 'Aged Brie' && @name != 'Backstage passes to a TAFKAL80ETC if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else if @quality < 50 @quality += 1 if @name == 'Backstage passes to a TAFKAL80ETC concert' if @days_remaining < 11 if @quality < 50 @quality += 1 end end if @days_remaining < 6 if @quality < 50 @quality += 1 end end end end end if @name != 'Sulfuras, Hand of Ragnaros' @days_remaining -‐= 1 end if @days_remaining < 0 if @name != "Aged Brie" if @name != 'Backstage passes to a TAFKAL80ETC concert' if @quality > 0 if @name != 'Sulfuras, Hand of Ragnaros' @quality -‐= 1 end end else @quality = @quality -‐ @quality end else if @quality < 50 @quality += 1 end end end end end big conditional Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remainin end end small methods class GildedRose attr_reader :name, :quality, :days_remaining def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end small objects Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 big conditional small methods small objects tick/for normal brie backstage other Total Complexity 40 50 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 big conditional small methods small objects tick/for normal brie backstage other 33 40 50 Total Complexity Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end big conditional small methods small objects 50 84 40 Total Complexity Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 45 90 big conditional small methods small objects 50 84 40 Total Complexity Friday, March 7, 14

def initialize(name, quality, days_remaining) @name, @quality, @days_remaining = name, quality, days_remaining end def tick case name when 'normal' normal_tick when 'Aged Brie' brie_tick when 'Sulfuras, Hand of Ragnaros' sulfuras_tick when 'Backstage passes to a TAFKAL80ETC concert' backstage_tick end end def normal_tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end def brie_tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end def sulfuras_tick end def backstage_tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end 0 45 90 big conditional small methods small objects 50 84 40 33 86 Total Complexity Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 big cond small meth small objs tick/for normal brie backstage other 33 Complexity 40 50 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose small meth small objs tick/for normal brie backstage other 33 Complexity 40 50 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose GildedRose(2) small objs tick/for normal brie backstage other 33 Complexity 40 50 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose GildedRose(2) many objs tick/for normal brie backstage other 33 Complexity 40 50 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose GildedRose(2) many objs Backstage tick/for normal brie backstage other 33 Complexity 40 50 12 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose GildedRose(2) many objs Backstage average tick/for normal brie backstage other 33 Complexity 40 50 7 12 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose Backstage Complexity 50 12 Friday, March 7, 14

attr_reader :quality, :days_remaining def initialize(quality, days_remaining) @quality, @days_remaining = quality, days_remaining end def tick end end class Normal < Item def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 1 @quality -‐= 1 if @days_remaining <= 0 end end class Brie < Item def tick @days_remaining -‐= 1 return if @quality >= 50 @quality += 1 @quality += 1 if @days_remaining <= 0 end end class Backstage < Item def tick @days_remaining -‐= 1 return if @quality >= 50 return @quality = 0 if @days_remaining < 0 @quality += 1 @quality += 1 if @days_remaining < 10 @quality += 1 if @days_remaining < 5 end end DEFAULT_CLASS = Item SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage } def self.for(name, quality, days_remaining) (SPECIALIZED_CLASSES[name] || DEFAULT_CLASS).new(quality, days_remaining) end end 0 25 50 GildedRose Backstage Complexity 50 12 75% Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose Friday, March 7, 14

@sandimetz Mar 2014 module GildedRose class Conjured < Item
def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 2 @quality -‐= 2 if @days_remaining <= 0 end end Friday, March 7, 14

def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 2 @quality -‐= 2 if @days_remaining <= 0 end end SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage} Friday, March 7, 14

def tick @days_remaining -‐= 1 return if @quality == 0 @quality -‐= 2 @quality -‐= 2 if @days_remaining <= 0 end end SPECIALIZED_CLASSES = { 'normal' => Normal, 'Aged Brie' => Brie, 'Backstage passes to a TAFKAL80ETC concert' => Backstage, 'Conjured Mana Cake' => Conjured } Friday, March 7, 14

@sandimetz Mar 2014 # Running: ............................... Fabulous run in 0.003917s,

@sandimetz Mar 2014 Summary Friday, March 7, 14

@sandimetz Mar 2014 duplication is far cheaper than the wrong
abstraction Friday, March 7, 14

@sandimetz Mar 2014 reach for open / closed Friday, March
7, 14

@sandimetz Mar 2014 small methods are simple Friday, March 7,
14

@sandimetz Mar 2014 small objects are simple Friday, March 7,
14

@sandimetz Mar 2014 refactor through complexity Friday, March 7, 14

@sandimetz Mar 2014 refactor into simplicity Friday, March 7, 14

@sandimetz Mar 2014 Thanks Friday, March 7, 14

@sandimetz Mar 2014 Thanks Jim Friday, March 7, 14

@sandimetz Mar 2014 Questions? Friday, March 7, 14

http://poodr.com Sandi Metz @sandimetz @sandimetz Mar 2014 Friday, March 7,
14

all the little things (rubyonales)

all the little things (rubyonales)

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