Adding Unit Test and Mocking Capability with Examples

build.gradle

@@ -88,6 +88,9 @@ dependencies {
     simulationRelease wpi.sim.enableRelease()
 
     testImplementation libs.junit.jupiter
+    testImplementation libs.mockito.core
+    testImplementation libs.mockito.junit.jupiter
+
     testRuntimeOnly libs.junit.platform.launcher
 }
 

gradle/libs.versions.toml

@@ -6,6 +6,8 @@ errorproneCore = "2.28.0"
 errorproneAnnotations = "2.28.0"
 junit = "5.10.1"
 junitPlatform = "1.10.1"
+mockito = "5.11.0"
+
 
 [libraries]
 wpilib-java = { module = "edu.wpi.first.gradle:edu.wpi.first.gradle.gradle.plugin", version.ref = "wpilib" }
@@ -17,6 +19,9 @@ errorprone-core = { module = "com.google.errorprone:error_prone_core", version.r
 
 junit-jupiter = { module = "org.junit.jupiter:junit-jupiter", version.ref = "junit" }
 junit-platform-launcher = { module = "org.junit.platform:junit-platform-launcher", version.ref = "junitPlatform" }
+mockito-core = { module = "org.mockito:mockito-core", version.ref = "mockito" }
+mockito-junit-jupiter = { module = "org.mockito:mockito-junit-jupiter", version.ref = "mockito" }
+
 [plugins]
 wpilib = { id = "edu.wpi.first.GradleRIO", version.ref = "wpilib" }
 spotless = { id = "com.diffplug.spotless", version.ref = "spotless" }

src/test/TestHowTo.md

@@ -0,0 +1,12 @@
+## How to Run Tests
+You can run the tests using the Gradle wrapper:
+
+```bash
+./gradlew test
+```
+
+## How to Debug Tests
+You can debug tests directly in VS Code:
+1. Open the test file (e.g., [src/test/java/frc/robot/ExampleTest.java](java/frc/robot/ExampleTest.java)).
+2. Click the "Run" or "Debug" codelens above the test method or class.
+3. Alternatively, use the Testing view in the sidebar to run or debug specific tests.

src/test/java/frc/robot/ExampleTest.java

@@ -0,0 +1,28 @@
+package frc.robot;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.function.DoubleSupplier;
+import org.junit.jupiter.api.Test;
+
+class ExampleTest {
+
+  @Test
+  void testMocking() {
+    // Create a mock object
+    DoubleSupplier mockSupplier = mock(DoubleSupplier.class);
+
+    // Define behavior
+    when(mockSupplier.getAsDouble()).thenReturn(10.0);
+
+    // Verify behavior
+    assertEquals(10.0, mockSupplier.getAsDouble(), 0.001);
+  }
+
+  @Test
+  void testBasicAssertion() {
+    assertEquals(2, 1 + 1);
+  }
+}

src/test/java/frc/robot/util/AllianceUtilsTest.java

@@ -0,0 +1,52 @@
+package frc.robot.util;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.mockStatic;
+
+import edu.wpi.first.wpilibj.DriverStation;
+import edu.wpi.first.wpilibj.DriverStation.Alliance;
+import java.util.Optional;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.MockedStatic;
+
+class AllianceUtilsTest {
+
+  private MockedStatic<DriverStation> mockedDriverStation;
+
+  @BeforeEach
+  void setUp() {
+    mockedDriverStation = mockStatic(DriverStation.class);
+  }
+
+  @AfterEach
+  void tearDown() {
+    mockedDriverStation.close();
+  }
+
+  @Test
+  void testIsBlue() {
+    mockedDriverStation.when(DriverStation::getAlliance).thenReturn(Optional.of(Alliance.Blue));
+
+    assertTrue(AllianceUtils.isBlue());
+    assertFalse(AllianceUtils.isRed());
+  }
+
+  @Test
+  void testIsRed() {
+    mockedDriverStation.when(DriverStation::getAlliance).thenReturn(Optional.of(Alliance.Red));
+
+    assertTrue(AllianceUtils.isRed());
+    assertFalse(AllianceUtils.isBlue());
+  }
+
+  @Test
+  void testNoAlliance() {
+    mockedDriverStation.when(DriverStation::getAlliance).thenReturn(Optional.empty());
+
+    assertFalse(AllianceUtils.isBlue());
+    assertFalse(AllianceUtils.isRed());
+  }
+}