feat: add should_have_a_subscription_tier_range_with_no_upper_limit test

Author: adrianliz

exercises/tiered_pricing/solutions/adrianliz/java/src/main/java/tv/codely/checkout/SubscriptionTier.java

@@ -24,4 +24,8 @@ public double unitPrice() {
     public double getTotalPrice(int numberOfSubscriptions) {
         return unitPrice() * numberOfSubscriptions;
     }
+
+    public boolean isLast() {
+        return range.isLast();
+    }
 }

exercises/tiered_pricing/solutions/adrianliz/java/src/main/java/tv/codely/checkout/SubscriptionTierRange.java

@@ -10,8 +10,16 @@ public SubscriptionTierRange(int numberOfSubscriptionsFrom, int numberOfSubscrip
         this.numberOfSubscriptionsTo = numberOfSubscriptionsTo;
     }
 
+    public static SubscriptionTierRange last(int numberOfSubscriptionsFrom) {
+        return new SubscriptionTierRange(numberOfSubscriptionsFrom, Integer.MAX_VALUE);
+    }
+
     public boolean isSuitableFor(int numberOfSubscriptions) {
         return numberOfSubscriptions >= numberOfSubscriptionsFrom
             && numberOfSubscriptions <= numberOfSubscriptionsTo;
     }
+
+    public boolean isLast() {
+        return numberOfSubscriptionsTo == Integer.MAX_VALUE;
+    }
 }

exercises/tiered_pricing/solutions/adrianliz/java/src/test/java/tv/codely/checkout/TieredPricingShould.java

@@ -1,6 +1,7 @@
 package tv.codely.checkout;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.util.List;
@@ -25,7 +26,7 @@ private static List<SubscriptionTier> defaultSubscriptionTiers() {
                 new SubscriptionTierRange(26, 50),
                 new SubscriptionTierPrice(199)),
             new SubscriptionTier(
-                new SubscriptionTierRange(51, 100),
+                SubscriptionTierRange.last(51),
                 new SubscriptionTierPrice(149)));
     }
 
@@ -47,6 +48,18 @@ void return_total_price_based_on_number_of_subscriptions() {
         assertEquals(expectedPrice, totalPrice);
     }
 
+    @Test
+    void should_have_a_subscription_tier_range_with_no_upper_limit() {
+        final var subscriptionTiers = SubscriptionTierMother.randoms();
+        final var lastSubscriptionTier =
+            subscriptionTiers.stream()
+                .filter(SubscriptionTier::isLast)
+                .findFirst()
+                .orElse(null);
+
+        assertNotNull(lastSubscriptionTier);
+    }
+
     @Test
     void return_total_price_for_1_subscription() {
         final var tieredPricing = new TieredPricing(defaultSubscriptionTiers());

exercises/tiered_pricing/solutions/adrianliz/java/src/test/java/tv/codely/checkout/mother/SubscriptionTierRangeMother.java

@@ -13,6 +13,10 @@ public static SubscriptionTierRange create(
         return new SubscriptionTierRange(numberOfSubscriptionsFrom, numberOfSubscriptionsTo);
     }
 
+    public static SubscriptionTierRange last(final int numberOfSubscriptionsFrom) {
+        return SubscriptionTierRange.last(numberOfSubscriptionsFrom);
+    }
+
     public static List<SubscriptionTierRange> randoms() {
         final var subscriptionTiers = new ArrayList<SubscriptionTierRange>();
         final var numberOfTiers = IntegerMother.randomBetween(1, 6);
@@ -23,6 +27,11 @@ public static List<SubscriptionTierRange> randoms() {
         var lastNumberOfSubscriptionsTo = 0;
 
         for (int i = 0; i < numberOfTiers; i++) {
+            if (i == numberOfTiers - 1) {
+                subscriptionTiers.add(last(lastNumberOfSubscriptionsTo + 1));
+                break;
+            }
+
             final var numberOfSubscriptionsFrom = lastNumberOfSubscriptionsTo + 1;
             final var numberOfSubscriptionsTo =
                 IntegerMother.randomBetween(