Day 17: One and thousand tests.

README.md

@@ -62,6 +62,7 @@ Here are the different challenges :
 - [Day 14: Do not use exceptions anymore.](exercise/day14/docs/challenge.md)
 - [Day 15: Put a code under tests.](exercise/day15/docs/challenge.md)
 - [Day 16: Make this code immutable.](exercise/day16/docs/challenge.md)
+- [Day 17: Design one test that has the impact of thousands.](exercise/day17/docs/challenge.md)
 
 ### Solutions
 A solution proposal will be published here every day during the `Advent Of Craft` containing `the code` and a `step by step` guide.

exercise/day17/docs/challenge.md

@@ -0,0 +1,23 @@
+## Day 17: One and thousand tests.
+
+Today, you are recovering at the nearby harbor to
+replenish your ship before the last week on the journey.
+
+Challenges are not going to lack and in order to face
+them, new skills are required.
+
+Today's exercise is about transforming your test in
+a way you've not done before.
+
+However, nothing is simple. You've got to think
+of your tests and your code differently.
+
+_What characteristic does my code have?_
+
+> **Day 17: Design one test that has the impact of thousands.**
+
+May your crafting journey bring you to new heights!
+
+- <u>💡HINT:</u> What PBT stands for.
+
+![snippet of the day](snippet.png)

exercise/day17/pom.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>com.advent-of-craft</groupId>
+        <artifactId>advent-of-craft2023</artifactId>
+        <version>1.0-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>fizzbuzz-part5</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <vavr.version>0.10.4</vavr.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.vavr</groupId>
+            <artifactId>vavr</artifactId>
+            <version>${vavr.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.vavr</groupId>
+            <artifactId>vavr-test</artifactId>
+            <version>${vavr.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>

exercise/day17/src/main/java/games/FizzBuzz.java

@@ -0,0 +1,39 @@
+package games;
+
+import io.vavr.collection.LinkedHashMap;
+import io.vavr.collection.Map;
+import io.vavr.control.Option;
+
+import static io.vavr.control.Option.none;
+import static io.vavr.control.Option.some;
+
+public class FizzBuzz {
+    public static final int MIN = 1;
+    public static final int MAX = 100;
+    private static final Map<Integer, String> mapping = LinkedHashMap.of(
+            15, "FizzBuzz",
+            3, "Fizz",
+            5, "Buzz"
+    );
+
+    public static Option<String> convert(int input) {
+        return isOutOfRange(input)
+                ? none()
+                : some(convertSafely(input));
+    }
+
+    private static String convertSafely(Integer input) {
+        return mapping
+                .find(p -> is(p._1, input))
+                .map(p -> p._2)
+                .getOrElse(input.toString());
+    }
+
+    private static boolean is(Integer divisor, Integer input) {
+        return input % divisor == 0;
+    }
+
+    private static boolean isOutOfRange(Integer input) {
+        return input < MIN || input > MAX;
+    }
+}

exercise/day17/src/test/java/games/FizzBuzzTests.java

@@ -0,0 +1,51 @@
+package games;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import java.util.stream.Stream;
+
+import static io.vavr.API.Some;
+import static org.assertj.core.api.Assertions.assertThat;
+
+class FizzBuzzTests {
+    private static Stream<Arguments> validInputs() {
+        return Stream.of(
+                Arguments.of(1, "1"),
+                Arguments.of(67, "67"),
+                Arguments.of(82, "82"),
+                Arguments.of(3, "Fizz"),
+                Arguments.of(66, "Fizz"),
+                Arguments.of(99, "Fizz"),
+                Arguments.of(5, "Buzz"),
+                Arguments.of(50, "Buzz"),
+                Arguments.of(85, "Buzz"),
+                Arguments.of(15, "FizzBuzz"),
+                Arguments.of(30, "FizzBuzz"),
+                Arguments.of(45, "FizzBuzz")
+        );
+    }
+
+    private static Stream<Arguments> invalidInputs() {
+        return Stream.of(
+                Arguments.of(0),
+                Arguments.of(-1),
+                Arguments.of(101)
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("validInputs")
+    void parse_successfully_numbers_between_1_and_100(int input, String expectedResult) {
+        assertThat(FizzBuzz.convert(input))
+                .isEqualTo(Some(expectedResult));
+    }
+
+    @ParameterizedTest
+    @MethodSource("invalidInputs")
+    void parse_fail_for_numbers_out_of_range(int input) {
+        assertThat(FizzBuzz.convert(input).isEmpty())
+                .isTrue();
+    }
+}

exercise/pom.xml

@@ -25,6 +25,7 @@
 		<module>day14</module>
 		<module>day15</module>
 		<module>day16</module>
+		<module>day17</module>
     </modules>
 
     <properties>