diff --git a/php/test/gilded_rose_test.php b/php/test/gilded_rose_test.php
index c18bfa05..cfab2e0f 100644
--- a/php/test/gilded_rose_test.php
+++ b/php/test/gilded_rose_test.php
@@ -2,13 +2,163 @@
 
 require_once 'gilded_rose.php';
 
-class GildedRoseTest extends PHPUnit_Framework_TestCase {
+/**
+ * A PHP port from https://gist.github.com/trikitrok/4627e7586180e48fe24d
+ */
+class GildedRoseTest extends PHPUnit_Framework_TestCase
+{
+    /**
+     * @var GildedRose
+     */
+    private $gildedRose;
 
-    function testFoo() {
-        $items = array(new Item("foo", 0, 0));
-        $gildedRose = new GildedRose($items);
-        $gildedRose->update_quality();
-        $this->assertEquals("fixme", $items[0]->name);
+    public function test_sulfurasIsInmutable()
+    {
+        $sulfuras = new Item("Sulfuras, Hand of Ragnaros", 0, 80);
+        $this->gildedRose = $this->aGildedRoseWithItems($sulfuras);
+
+        $this->afterDays(10);
+
+        $this->assertItemsQuality(80, $sulfuras);
+        $this->assertEquals(0, $sulfuras->sell_in);
     }
 
+
+    public function test_sellInDecreasesByOneEachDay()
+    {
+        $notSulfuras = new Item("notSulfuras", 2, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($notSulfuras);
+
+        $this->afterDays(10);
+
+        $this->assertEquals(-8, $notSulfuras->sell_in);
+    }
+
+
+    public function test_agedBrieQualityIncreasesByOneEachDayBeforeSellDate()
+    {
+        $agedBrie = new Item("Aged Brie", 2, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($agedBrie);
+
+        $this->afterDays(2);
+
+        $this->assertItemsQuality(2, $agedBrie);
+    }
+
+
+    public function test_agedBrieQualityIncreasesByTwoEachDayAfterSellDate()
+    {
+        $agedBrie = new Item("Aged Brie", 0, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($agedBrie);
+
+        $this->afterDays(2);
+
+        $this->assertItemsQuality(4, $agedBrie);
+    }
+
+
+    public function test_qualityCannotBeMoreThanFifty()
+    {
+        $agedBrie = new Item("Aged Brie", 2, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($agedBrie);
+
+        $this->afterDays(300);
+
+        $this->assertItemsQuality(50, $agedBrie);
+    }
+
+
+    public function test_backstagePassesQualityIncreasesByOneEachDayBeforeTenDaysFromSellDate()
+    {
+        $backstagePasses = new Item("Backstage passes to a TAFKAL80ETC concert", 15, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($backstagePasses);
+
+        $this->afterDays(5);
+
+        $this->assertItemsQuality(5, $backstagePasses);
+    }
+
+
+    public function test_backstagePassesQualityIncreasesByTwoEachDayBetweenTenAndFiveDaysBeforeSellDate()
+    {
+        $backstagePasses = new Item("Backstage passes to a TAFKAL80ETC concert", 15, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($backstagePasses);
+
+        $this->afterDays(7);
+
+        $this->assertItemsQuality(9, $backstagePasses);
+    }
+
+
+    public function test_backstagePassesQualityIncreasesByThreeEachDayBetweenFiveDaysFromSellDateAndSellDate()
+    {
+        $backstagePasses = new Item("Backstage passes to a TAFKAL80ETC concert", 15, 0);
+        $this->gildedRose = $this->aGildedRoseWithItems($backstagePasses);
+
+        $this->afterDays(15);
+
+        $this->assertItemsQuality(30, $backstagePasses);
+    }
+
+
+    public function test_backstagePassesQualityIsZeroAfterTheSellDate()
+    {
+        $backstagePasses = new Item("Backstage passes to a TAFKAL80ETC concert", 15, 20);
+        $this->gildedRose = $this->aGildedRoseWithItems($backstagePasses);
+
+        $this->afterDays(16);
+
+        $this->assertItemsQuality(0, $backstagePasses);
+    }
+
+
+    public function test_perishableItemsQualityDecreasesByOneEachDayBeforeSellDate()
+    {
+        $regularItem = new Item("+5 Dexterity Vest", 10, 20);
+        $this->gildedRose = $this->aGildedRoseWithItems($regularItem);
+
+        $this->afterDays(10);
+
+        $this->assertItemsQuality(10, $regularItem);
+    }
+
+
+    public function test_perishableItemsQualityDecreasesByTwoEachDayAfterSellDate()
+    {
+        $perishableItem = new Item("+5 Dexterity Vest", 10, 20);
+        $this->gildedRose = $this->aGildedRoseWithItems($perishableItem);
+
+        $this->afterDays(15);
+
+        $this->assertItemsQuality(0, $perishableItem);
+    }
+
+
+    public function test_perishableItemsQualityCannotBeLessThanZero()
+    {
+        $perishableItem = new Item("+5 Dexterity Vest", 10, 20);
+        $this->gildedRose = $this->aGildedRoseWithItems($perishableItem);
+
+        $this->afterDays(200);
+
+        $this->assertItemsQuality(0, $perishableItem);
+    }
+
+
+    private function afterDays($numberOfDays)
+    {
+        for ($i = 0; $i < $numberOfDays; ++$i) {
+            $this->gildedRose->update_quality();
+        }
+    }
+
+    private function assertItemsQuality($quality, $item)
+    {
+        $this->assertEquals($quality, $item->quality);
+    }
+
+    private function aGildedRoseWithItems($items)
+    {
+        return new GildedRose(array($items));
+    }
 }