Add test module and auto-discovery for XTC tests

.github/workflows/commit.yml

@@ -21,9 +21,6 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v4
 
-    - name: Validate Gradle wrapper
-      uses: gradle/wrapper-validation-action@v3
-
     - name: Set up JDK 25
       uses: actions/setup-java@v4
       with:

hello-xtc/build.gradle.kts

@@ -27,6 +27,15 @@ xtcRun {
     }
 }
 
+// Note: The xtcTest task auto-discovers test modules from src/test/x.
+// No explicit module configuration is needed - just place test modules in
+// the test source set and they will be run as part of the build lifecycle.
+// You can optionally configure test behavior here:
+// xtcTest {
+//     failOnTestFailure = true  // default
+//     // includes/excludes can be used to filter test modules
+// }
+
 // Print version information
 val printVersionInfo by tasks.registering {
     val xtcVersionTask = tasks.named<XtcVersionTask>("xtcVersion")

hello-xtc/src/main/x/HelloWorld.x

@@ -1,7 +1,19 @@
 module HelloWorld {
+    /**
+     * Format a greeting from the provided parts.
+     *
+     * @param prefix    the greeting prefix (e.g., "Hello ")
+     * @param middle    the middle part (e.g., "there, ")
+     * @param name      the name to greet (e.g., "World")
+     *
+     * @return the formatted greeting string with an exclamation mark
+     */
+    static String formatGreeting(String prefix, String middle, String name) {
+        return $"{prefix}{middle}{name}!";
+    }
+
     void run(String[] args = []) {
         @Inject Console console;
-        //assert:debug;
-        console.print($"{args[0]}{args[1]}{args[2]}!");
+        console.print(formatGreeting(args[0], args[1], args[2]));
     }
 }

hello-xtc/src/test/x/HelloWorldTest.x

@@ -0,0 +1,44 @@
+/**
+ * Unit tests for the HelloWorld module's greeting functionality.
+ *
+ * This test module demonstrates how to write xunit tests that are run
+ * as part of the Gradle build lifecycle via the `testXtc` task.
+ */
+module HelloWorldTest {
+    package greeting import HelloWorld;
+
+    /**
+     * Tests for the formatGreeting() function.
+     */
+    class GreeterTest {
+        @Test
+        void shouldFormatBasicGreeting() {
+            String result = greeting.formatGreeting("Hello ", "there, ", "World");
+            assert result == "Hello there, World!";
+        }
+
+        @Test
+        void shouldFormatGreetingWithCustomName() {
+            String result = greeting.formatGreeting("Hello ", "there, ", "Marcus");
+            assert result == "Hello there, Marcus!";
+        }
+
+        @Test
+        void shouldFormatGreetingWithEmptyParts() {
+            String result = greeting.formatGreeting("", "", "Test");
+            assert result == "Test!";
+        }
+
+        @Test
+        void shouldFormatGreetingWithDifferentPrefix() {
+            String result = greeting.formatGreeting("Hi ", "dear ", "Friend");
+            assert result == "Hi dear Friend!";
+        }
+
+        @Test
+        void shouldAlwaysAppendExclamationMark() {
+            String result = greeting.formatGreeting("A", "B", "C");
+            assert result.endsWith("!");
+        }
+    }
+}