requested changes

app/gilded-rose-refactor.ts

@@ -0,0 +1,69 @@
+export class Item {
+    name: string;
+    sellIn: number;
+    quality: number;
+
+    constructor(name, sellIn, quality) {
+        this.name = name;
+        this.sellIn = sellIn;
+        this.quality = quality;
+    }
+}
+
+export class GildedRose {
+    items: Array<Item>;
+
+    constructor(items = [] as Array<Item>) {
+        this.items = items;
+    }
+
+    updateQuality() {
+        for (let i = 0; i < this.items.length; i++)
+        {
+            if (this.items[i].name == 'Aged Brie')
+            {                
+                this.items[i].sellIn -= 1
+
+                if (this.items[i].quality < 50)
+                    this.items[i].quality += 1
+
+                if (this.items[i].sellIn < 0 &&
+                    this.items[i].quality < 50)
+                    this.items[i].quality += 1
+            }
+
+            if (this.items[i].name == 'Backstage passes to a TAFKAL80ETC concert')
+            {                
+                this.items[i].sellIn -= 1
+
+                if (this.items[i].sellIn < 0)
+                    this.items[i].quality = 0
+                else
+                    if (this.items[i].quality < 50)
+                    {
+                        this.items[i].quality += 1
+
+                        if (this.items[i].sellIn < 11 &&
+                            this.items[i].quality < 50)
+                            this.items[i].quality += 1
+
+                        if (this.items[i].sellIn < 6 &&
+                            this.items[i].quality < 50)
+                            this.items[i].quality += 1
+                    }
+            }
+
+            if (this.items[i].name != 'Aged Brie' &&
+                this.items[i].name != 'Backstage passes to a TAFKAL80ETC concert' &&
+                this.items[i].name != 'Sulfuras, Hand of Ragnaros') 
+            {
+                this.items[i].sellIn -= 1
+
+                if (this.items[i].quality > 0)
+                    this.items[i].quality -= 1
+            }
+        }
+
+        return this.items;
+    }
+}

app/gilded-rose.ts

@@ -16,7 +16,7 @@ export class GildedRose {
     constructor(items = [] as Array<Item>) {
         this.items = items;
     }
-
+    
     updateQuality() {
         for (let i = 0; i < this.items.length; i++) {
             if (this.items[i].name != 'Aged Brie' && this.items[i].name != 'Backstage passes to a TAFKAL80ETC concert') {

test/jest/gilded-rose.spec.ts

@@ -1,9 +1,9 @@
-import { Item, GildedRose } from '@/gilded-rose';
+import { Item, GildedRose } from '@/gilded-rose-refactor';
 
 describe('Gilded Rose', () => {
     it('should foo', () => {
         // Arrange
-        const gildedRose = new GildedRose([new Item('foo', 0, 0)]);
+        const gildedRose = new GildedRose([new Item('bar', 0, 0)]);
 
         // Act
         const items = gildedRose.updateQuality();
@@ -14,12 +14,74 @@ describe('Gilded Rose', () => {
 
     it('sword quality drops by 1', () => {
       // Arrange
-      const gildedRose = new GildedRose([new Item('Sword', 1, 1)]);
+      const gildedRose = new GildedRose([new Item('Sword', 1, 2)]);
 
       // Act
       const items = gildedRose.updateQuality();
 
       // Assert
       expect(items[0].quality).toBe(1);
     })
+
+    it('quality goes 0 on name \'Backstage passes to a TAFKAL80ETC concert\' and sellIn <= 0', () => {
+      // Arrange
+      const gildedRose = new GildedRose([new Item('Backstage passes to a TAFKAL80ETC concert', 0, -4)]);
+
+      // Act
+      const items = gildedRose.updateQuality();
+
+      // Assert
+      expect(items[0].quality).toBe(0);
+    })
+
+    it('name == \'Aged Brie\'', () => {
+      // Arrange
+      const gildedRose = new GildedRose([new Item('Aged Brie', 1, 49), new Item('Aged Brie', 0, 48), new Item('Aged Brie', 0, 70)]);
+
+      // Act
+      const items = gildedRose.updateQuality();
+
+      // Assert
+      expect(items[0].quality).toBe(50);
+      expect(items[1].quality).toBe(50);
+      expect(items[2].quality).toBe(70);
+    })
+
+    it('name == \'Backstage passes to a TAFKAL80ETC concert\'', () => {
+      // Arrange
+      const gildedRose = new GildedRose([new Item('Backstage passes to a TAFKAL80ETC concert', 5, 47), 
+                                         new Item('Backstage passes to a TAFKAL80ETC concert', 7, 45), 
+                                         new Item('Backstage passes to a TAFKAL80ETC concert', 7, 70)]);
+
+      // Act
+      const items = gildedRose.updateQuality();
+
+      // Assert
+      expect(items[0].quality).toBe(50);
+      expect(items[1].quality).toBe(47);
+      expect(items[2].quality).toBe(70);
+    })
+
+    it('name == \'Sulfuras, Hand of Ragnaros\'', () => {
+      // Arrange
+      const gildedRose = new GildedRose([new Item('Sulfuras, Hand of Ragnaros', 5, 48)]);
+
+      // Act
+      const items = gildedRose.updateQuality();
+
+      // Assert
+      expect(items[0].sellIn).toBe(5);
+      expect(items[0].quality).toBe(48);
+    })
+
+    it('foo name', () => {
+      // Arrange
+      const gildedRose = new GildedRose([new Item('foo', 5, 50)]);
+
+      // Act
+      const items = gildedRose.updateQuality();
+
+      // Assert
+      expect(items[0].quality).toBe(49);
+    })
 });