To allow new domain to replace god object antipattern, make business logic work in gilded rose item classes

php/src/GildedRoseItem/BackstagePassItem.php

@@ -15,5 +15,22 @@ class BackstagePassItem implements GildedRoseItem
 
     public function ageByOneDay(): void
     {
+        $this->item->sellIn -= 1;
+
+        if ($this->item->quality < 50) {
+            $this->item->quality += 1;
+
+            if ($this->item->sellIn <= 10 && $this->item->quality < 50) {
+                $this->item->quality += 1;
+            }
+
+            if ($this->item->sellIn <= 5 && $this->item->quality < 50) {
+                $this->item->quality += 1;
+            }
+        }
+
+        if ($this->item->sellIn < 0) {
+            $this->item->quality = 0;
+        }
     }
 }

php/src/GildedRoseItem/BrieItem.php

@@ -15,5 +15,10 @@ class BrieItem implements GildedRoseItem
 
     public function ageByOneDay(): void
     {
+        $this->item->sellIn -= 1;
+
+        if ($this->item->quality < 50) {
+            $this->item->quality += 1;
+        }
     }
 }

php/src/GildedRoseItem/DefaultItem.php

@@ -13,5 +13,10 @@ class DefaultItem implements GildedRoseItem
 
     public function ageByOneDay(): void
     {
+        $this->item->sellIn -= 1;
+
+        if ($this->item->quality >= 1) {
+            $this->item->quality -= 1;
+        }
     }
 }

php/tests/phpunit/GildedRoseItem/BackstagePassItemTest.php

@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitTests\GildedRoseItem;
+
+use ApprovalTests\Approvals;
+use GildedRose\GildedRoseItem;
+use GildedRose\GildedRoseItem\BackstagePassItem;
+use GildedRose\GildedRoseItemFactory;
+use GildedRose\Item;
+use PHPUnit\Framework\TestCase;
+
+class BackstagePassItemTest extends TestCase
+{
+    public function testQualityIncreases(): void
+    {
+        $item = new Item(BackstagePassItem::NAME, 20, 20);
+        $gildedRoseItem = new BackstagePassItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(21, $item->quality);
+    }
+
+    public function testQualityIncreasesFasterUnder10Days(): void
+    {
+        $item = new Item(BackstagePassItem::NAME, 10, 20);
+        $gildedRoseItem = new BackstagePassItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(22, $item->quality);
+    }
+
+    public function testQualityIncreasesEvenFasterUnder5Days(): void
+    {
+        $item = new Item(BackstagePassItem::NAME, 5, 20);
+        $gildedRoseItem = new BackstagePassItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(23, $item->quality);
+    }
+
+    public function testQualityIsZeroAfterConcert(): void
+    {
+        $item = new Item(BackstagePassItem::NAME, 0, 20);
+        $gildedRoseItem = new BackstagePassItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(0, $item->quality);
+    }
+}

php/tests/phpunit/GildedRoseItem/BrieItemTest.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitTests\GildedRoseItem;
+
+use ApprovalTests\Approvals;
+use GildedRose\GildedRoseItem;
+use GildedRose\GildedRoseItem\BrieItem;
+use GildedRose\GildedRoseItemFactory;
+use GildedRose\Item;
+use PHPUnit\Framework\TestCase;
+
+class BrieItemTest extends TestCase
+{
+    public function testQualityIncreases(): void
+    {
+        $item = new Item(BrieItem::NAME, 20, 20);
+        $gildedRoseItem = new BrieItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(21, $item->quality);
+    }
+
+    public function testQualityCantGoOver50(): void
+    {
+        $item = new Item(BrieItem::NAME, 20, 50);
+        $gildedRoseItem = new BrieItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(50, $item->quality);
+    }
+}

php/tests/phpunit/GildedRoseItem/DefaultItemTest.php

@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitTests\GildedRoseItem;
+
+use ApprovalTests\Approvals;
+use GildedRose\GildedRoseItem;
+use GildedRose\GildedRoseItem\DefaultItem;
+use GildedRose\GildedRoseItemFactory;
+use GildedRose\Item;
+use PHPUnit\Framework\TestCase;
+
+class DefaultItemTest extends TestCase
+{
+    public function testNormalQualityReduction(): void
+    {
+        $item = new Item('foo', 20, 20);
+        $gildedRoseItem = new DefaultItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(19, $item->quality);
+        $this->assertEquals(19, $item->sellIn);
+    }
+
+    public function testQualityCantBeNegative(): void
+    {
+        $item = new Item('foo', 20, 0);
+        $gildedRoseItem = new DefaultItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(0, $item->quality);
+    }
+}

php/tests/phpunit/GildedRoseItem/SulfurasItemTest.php

@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitTests\GildedRoseItem;
+
+use ApprovalTests\Approvals;
+use GildedRose\GildedRoseItem;
+use GildedRose\GildedRoseItem\SulfurasItem;
+use GildedRose\GildedRoseItemFactory;
+use GildedRose\Item;
+use PHPUnit\Framework\TestCase;
+
+class SulfurasItemTest extends TestCase
+{
+    public function testTimelessness(): void
+    {
+        $item = new Item(SulfurasItem::NAME, 20, 20);
+        $gildedRoseItem = new SulfurasItem($item);
+        $gildedRoseItem->ageByOneDay();
+
+        $this->assertEquals(20, $item->quality);
+        $this->assertEquals(20, $item->sellIn);
+    }
+}