more Backstage passes tests

Java/src/test/java/com/gildedrose/GildedRoseBackstageTest.java

@@ -2,11 +2,13 @@ package com.gildedrose;
 
 import io.qameta.allure.Feature;
 import io.qameta.allure.Story;
+import lombok.val;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 
 import static com.gildedrose.TestHelper.assertItem;
 import static com.gildedrose.TestHelper.prepareApp;
+import static org.apache.commons.lang3.RandomUtils.nextInt;
 
 
 @Story("\"Backstage passes\", like aged brie, increases in Quality as its SellIn value approaches;\n" +
@@ -16,12 +18,63 @@ class GildedRoseBackstageTest {
 
     private static final String ITEM_NAME = "Backstage passes to a TAFKAL80ETC concert";
 
+    @Feature("Quality increases by 2 when there are 10 days or less")
+    @ParameterizedTest(name = "sellIn: {arguments}")
+    @ValueSource(ints = {10, 9, 8, 7, 6})
+    void shouldIncreaseQualityBy2WhenThereAre10DaysOrLess(int sellIn) {
+        // given
+        val initialQuality = nextInt(10, 40);
+        GildedRose app = prepareApp(new Item(ITEM_NAME, sellIn, initialQuality));
+
+        // when
+        app.updateQuality();
+
+        // then
+        final Item item = app.items[0];
+        assertItem(item, ITEM_NAME, sellIn - 1, initialQuality + 2);
+    }
+
+    @Feature("Quality increases by 3 when there are 5 days or less")
+    @ParameterizedTest(name = "sellIn: {arguments}")
+    @ValueSource(ints = {5, 4, 3, 2, 1})
+    void shouldIncreaseQualityBy32WhenThereAre5DaysOrLess(int sellIn) {
+        // given
+        val initialQuality = nextInt(10, 40);
+        GildedRose app = prepareApp(new Item(ITEM_NAME, sellIn, initialQuality));
+
+        // when
+        app.updateQuality();
+
+        // then
+        final Item item = app.items[0];
+        assertItem(item, ITEM_NAME, sellIn - 1, initialQuality + 3);
+    }
+
+
     @Feature("Quality drops to 0 after the concert")
     @ParameterizedTest(name = "sellIn: {arguments}")
     @ValueSource(ints = {0, -1})
     void shouldDropQualityToZeroAfterTheConcert(int sellIn) {
         // given
-        GildedRose app = prepareApp(new Item(ITEM_NAME, sellIn, 10));
+        val initialQuality = nextInt(10, 40);
+        GildedRose app = prepareApp(new Item(ITEM_NAME, sellIn, initialQuality));
+
+        // when
+        app.updateQuality();
+
+        // then
+        final Item item = app.items[0];
+        assertItem(item, ITEM_NAME, sellIn - 1, 0);
+    }
+
+
+    @Feature("The Quality of an item is never more than 50")
+    @ParameterizedTest(name = "sellIn: {arguments}")
+    @ValueSource(ints = {0, -1})
+    void shouldNotIncreaseQualityAbove50(int sellIn) {
+        // given
+        val initialQuality = nextInt(10, 40);
+        GildedRose app = prepareApp(new Item(ITEM_NAME, sellIn, initialQuality));
 
         // when
         app.updateQuality();