Add test for InterpolatingDoubleTreeMap class from WPI. To run unit t…

…ests, right-click on the test directory and choose the "Run Tests" option.

build.gradle

@@ -161,4 +161,9 @@ idea {
         // Exclude the .vscode directory from indexing and search
         excludeDirs+=file(".vscode" )
     }
+}
+
+test {
+    useJUnitPlatform()
+    systemProperty 'junit.jupiter.extensions.autodetection.enabled', 'true'
 }

src/test/java/InterpolationTest.java

@@ -0,0 +1,67 @@
+import edu.wpi.first.math.interpolation.InterpolatingDoubleTreeMap;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * Demonstrate how WPILib class InterpolatingDoubleTreeMap works
+ */
+class InterpolationTest {
+
+    static final InterpolatingDoubleTreeMap SHOOTER_ANGLE_LOW_FRONT = new InterpolatingDoubleTreeMap();
+    static {
+        // First number is the distance in feet. Second number is the shooter angle.
+        SHOOTER_ANGLE_LOW_FRONT.put(0.0, 54.0);
+        SHOOTER_ANGLE_LOW_FRONT.put(6.0, 27.0);
+        SHOOTER_ANGLE_LOW_FRONT.put(12.0, 24.0);
+        SHOOTER_ANGLE_LOW_FRONT.put(18.0, 22.0);
+        SHOOTER_ANGLE_LOW_FRONT.put(24.0, 20.0);
+    }
+
+    static final InterpolatingDoubleTreeMap SHOOTER_ANGLE_LOW_BACK = new InterpolatingDoubleTreeMap();
+    static {
+        // First number is the distance in feet. Second number is the shooter angle.
+        SHOOTER_ANGLE_LOW_BACK.put(0.0, 54.0);
+        SHOOTER_ANGLE_LOW_BACK.put(6.0, 27.0);
+        SHOOTER_ANGLE_LOW_BACK.put(12.0, 24.0);
+        SHOOTER_ANGLE_LOW_BACK.put(18.0, 22.0);
+        SHOOTER_ANGLE_LOW_BACK.put(24.0, 20.0);
+    }
+
+    @BeforeEach // this method will run before each test
+    void setup() {
+    }
+
+    @AfterEach // this method will run after each test
+    void shutdown() throws Exception {
+    }
+
+    @Test // marks this method as a test
+    void valuesThatWereMeasured() {
+        assertEquals(20.0, SHOOTER_ANGLE_LOW_FRONT.get(24.0));
+        assertEquals(54.0, SHOOTER_ANGLE_LOW_FRONT.get(0.0));
+    }
+
+    @Test // marks this method as a test
+    void valuesThatWereNotMeasured() {
+        // Test the angle halfway between two measured points
+        assertEquals(27.0 + (54.0 - 27.0)/2.0, SHOOTER_ANGLE_LOW_FRONT.get(3.0));
+        assertEquals(24.0 + (27.0 - 24.0)/2.0, SHOOTER_ANGLE_LOW_FRONT.get(9.0));
+    }
+    @Test // marks this method as a test
+    void valueGreaterThanLargestMeasurement() {
+        // The angle never goes lower than the last measurement made
+        assertEquals(20.0, SHOOTER_ANGLE_LOW_FRONT.get(90.0));
+    }
+
+    @Test
+    void valueVeryCloseToMeasuredValue() {
+        double shooterAngle = SHOOTER_ANGLE_LOW_FRONT.get(18.7);
+        System.out.print(shooterAngle);
+        assertNotEquals(22.0, shooterAngle);
+        assertTrue(shooterAngle < 22.0);
+        assertTrue(shooterAngle > 21.7);
+    }
+}