Extract Backstage Passes

ruby/gilded_rose.rb

@@ -9,6 +9,8 @@ class GildedRose
       case item.name
       when 'Aged Brie'
         update_aged_brie_quality(item)
+      when 'Backstage passes to a TAFKAL80ETC concert'
+        update_backstage_passes_quality(item)
       when 'Sulfuras, Hand of Ragnaros'
         update_sulfuras_quality(item)
       else
@@ -61,6 +63,16 @@ class GildedRose
     item.quality = 50 if item.quality > 50
   end
 
+  def update_backstage_passes_quality(item)
+    item.sell_in -= 1
+    return item.quality = 0 if item.sell_in.negative?
+
+    item.quality += 1
+    item.quality += 1 if item.sell_in < 10
+    item.quality += 1 if item.sell_in < 5
+    item.quality = 50 if item.quality > 50
+  end
+
   def update_sulfuras_quality(item); end
 end
 

ruby/specs/gilded_rose_spec.rb

@@ -188,7 +188,7 @@ describe GildedRose do
       context 'when 1 day left' do
         let(:sell_in) { 1 }
 
-        it 'increases quality by 1' do
+        it 'increases quality by 3' do
           subject.update_quality
           expect(items[0].quality).to eq 6
         end
@@ -202,7 +202,7 @@ describe GildedRose do
       context 'when sell by date has passed' do
         let(:sell_in) { 0 }
 
-        it 'increases quality by 2' do
+        it 'sets the quality to 0' do
           subject.update_quality
           expect(items[0].quality).to eq 0
         end