Don't force public variables to use Hungarian notation (#8774)

People generally have expressed a dislike for the Hungarian notation
used in member variables, especially in examples/templates, and our
styleguide shouldn't be forced on downstream consumers, so this removes
all Hungarian notation from the examples/templates.

There are _some_ benefits to Hungarian for private member variables
(like knowing what's a member vs. local in a PR review) so we'll keep
private member variables the same for now, but public variables should
no longer use Hungarian notation, since it looks much worse. A new PMD
XPath rule has been added to accomplish this goal. Some other
non-compliant variables were fixed for the new rule.

wpilibjExamples/src/test/java/org/wpilib/examples/armsimulation/ArmSimulationTest.java

@@ -25,12 +25,12 @@ import org.wpilib.util.Preferences;
 
 @ResourceLock("timing")
 class ArmSimulationTest {
-  private Robot m_robot;
-  private Thread m_thread;
+  private Robot robot;
+  private Thread thread;
 
-  private PWMMotorControllerSim m_motorSim;
-  private EncoderSim m_encoderSim;
-  private JoystickSim m_joystickSim;
+  private PWMMotorControllerSim motorSim;
+  private EncoderSim encoderSim;
+  private JoystickSim joystickSim;
 
   @BeforeEach
   void startThread() {
@@ -38,27 +38,27 @@ class ArmSimulationTest {
     SimHooks.pauseTiming();
     SimHooks.setProgramStarted(false);
     DriverStationSim.resetData();
-    m_robot = new Robot();
-    m_thread = new Thread(m_robot::startCompetition);
-    m_encoderSim = EncoderSim.createForChannel(Constants.kEncoderAChannel);
-    m_motorSim = new PWMMotorControllerSim(Constants.kMotorPort);
-    m_joystickSim = new JoystickSim(Constants.kJoystickPort);
+    robot = new Robot();
+    thread = new Thread(robot::startCompetition);
+    encoderSim = EncoderSim.createForChannel(Constants.kEncoderAChannel);
+    motorSim = new PWMMotorControllerSim(Constants.kMotorPort);
+    joystickSim = new JoystickSim(Constants.kJoystickPort);
 
-    m_thread.start();
+    thread.start();
     SimHooks.waitForProgramStart();
   }
 
   @AfterEach
   void stopThread() {
-    m_robot.endCompetition();
+    robot.endCompetition();
     try {
-      m_thread.interrupt();
-      m_thread.join();
+      thread.interrupt();
+      thread.join();
     } catch (InterruptedException ex) {
       Thread.currentThread().interrupt();
     }
-    m_robot.close();
-    m_encoderSim.resetData();
+    robot.close();
+    encoderSim.resetData();
     Preferences.remove(Constants.kArmPKey);
     Preferences.remove(Constants.kArmPositionKey);
     Preferences.removeAll();
@@ -80,7 +80,7 @@ class ArmSimulationTest {
       DriverStationSim.setEnabled(true);
       DriverStationSim.notifyNewData();
 
-      assertTrue(m_encoderSim.getInitialized());
+      assertTrue(encoderSim.getInitialized());
     }
 
     {
@@ -88,50 +88,50 @@ class ArmSimulationTest {
       SimHooks.stepTiming(3);
 
       // Ensure arm is still at minimum angle.
-      assertEquals(Constants.kMinAngleRads, m_encoderSim.getDistance(), 2.0);
+      assertEquals(Constants.kMinAngleRads, encoderSim.getDistance(), 2.0);
     }
 
     {
       // Press button to reach setpoint
-      m_joystickSim.setTrigger(true);
-      m_joystickSim.notifyNewData();
+      joystickSim.setTrigger(true);
+      joystickSim.notifyNewData();
 
       // advance 75 timesteps
       SimHooks.stepTiming(1.5);
 
-      assertEquals(setpoint, Units.radiansToDegrees(m_encoderSim.getDistance()), 2.0);
+      assertEquals(setpoint, Units.radiansToDegrees(encoderSim.getDistance()), 2.0);
 
       // advance 25 timesteps to see setpoint is held.
       SimHooks.stepTiming(0.5);
 
-      assertEquals(setpoint, Units.radiansToDegrees(m_encoderSim.getDistance()), 2.0);
+      assertEquals(setpoint, Units.radiansToDegrees(encoderSim.getDistance()), 2.0);
     }
 
     {
       // Unpress the button to go back down
-      m_joystickSim.setTrigger(false);
-      m_joystickSim.notifyNewData();
+      joystickSim.setTrigger(false);
+      joystickSim.notifyNewData();
 
       // advance 150 timesteps
       SimHooks.stepTiming(3.0);
 
-      assertEquals(Constants.kMinAngleRads, m_encoderSim.getDistance(), 2.0);
+      assertEquals(Constants.kMinAngleRads, encoderSim.getDistance(), 2.0);
     }
 
     {
       // Press button to go back up
-      m_joystickSim.setTrigger(true);
-      m_joystickSim.notifyNewData();
+      joystickSim.setTrigger(true);
+      joystickSim.notifyNewData();
 
       // advance 75 timesteps
       SimHooks.stepTiming(1.5);
 
-      assertEquals(setpoint, Units.radiansToDegrees(m_encoderSim.getDistance()), 2.0);
+      assertEquals(setpoint, Units.radiansToDegrees(encoderSim.getDistance()), 2.0);
 
       // advance 25 timesteps to see setpoint is held.
       SimHooks.stepTiming(0.5);
 
-      assertEquals(setpoint, Units.radiansToDegrees(m_encoderSim.getDistance()), 2.0);
+      assertEquals(setpoint, Units.radiansToDegrees(encoderSim.getDistance()), 2.0);
     }
 
     {
@@ -142,8 +142,8 @@ class ArmSimulationTest {
       // advance 75 timesteps
       SimHooks.stepTiming(3.5);
 
-      assertEquals(0.0, m_motorSim.getThrottle(), 0.01);
-      assertEquals(Constants.kMinAngleRads, m_encoderSim.getDistance(), 2.0);
+      assertEquals(0.0, motorSim.getThrottle(), 0.01);
+      assertEquals(Constants.kMinAngleRads, encoderSim.getDistance(), 2.0);
     }
   }
 }

wpilibjExamples/src/test/java/org/wpilib/examples/elevatorsimulation/ElevatorSimulationTest.java

@@ -22,12 +22,12 @@ import org.wpilib.simulation.SimHooks;
 
 @ResourceLock("timing")
 class ElevatorSimulationTest {
-  private Robot m_robot;
-  private Thread m_thread;
+  private Robot robot;
+  private Thread thread;
 
-  private PWMMotorControllerSim m_motorSim;
-  private EncoderSim m_encoderSim;
-  private JoystickSim m_joystickSim;
+  private PWMMotorControllerSim motorSim;
+  private EncoderSim encoderSim;
+  private JoystickSim joystickSim;
 
   @BeforeEach
   void startThread() {
@@ -35,27 +35,27 @@ class ElevatorSimulationTest {
     SimHooks.pauseTiming();
     SimHooks.setProgramStarted(false);
     DriverStationSim.resetData();
-    m_robot = new Robot();
-    m_thread = new Thread(m_robot::startCompetition);
-    m_encoderSim = EncoderSim.createForChannel(Constants.kEncoderAChannel);
-    m_motorSim = new PWMMotorControllerSim(Constants.kMotorPort);
-    m_joystickSim = new JoystickSim(Constants.kJoystickPort);
+    robot = new Robot();
+    thread = new Thread(robot::startCompetition);
+    encoderSim = EncoderSim.createForChannel(Constants.kEncoderAChannel);
+    motorSim = new PWMMotorControllerSim(Constants.kMotorPort);
+    joystickSim = new JoystickSim(Constants.kJoystickPort);
 
-    m_thread.start();
+    thread.start();
     SimHooks.waitForProgramStart();
   }
 
   @AfterEach
   void stopThread() {
-    m_robot.endCompetition();
+    robot.endCompetition();
     try {
-      m_thread.interrupt();
-      m_thread.join();
+      thread.interrupt();
+      thread.join();
     } catch (InterruptedException ex) {
       Thread.currentThread().interrupt();
     }
-    m_robot.close();
-    m_encoderSim.resetData();
+    robot.close();
+    encoderSim.resetData();
     RoboRioSim.resetData();
     DriverStationSim.resetData();
     DriverStationSim.notifyNewData();
@@ -69,7 +69,7 @@ class ElevatorSimulationTest {
       DriverStationSim.setEnabled(true);
       DriverStationSim.notifyNewData();
 
-      assertTrue(m_encoderSim.getInitialized());
+      assertTrue(encoderSim.getInitialized());
     }
 
     {
@@ -77,50 +77,50 @@ class ElevatorSimulationTest {
       SimHooks.stepTiming(1);
 
       // Ensure elevator is still at 0.
-      assertEquals(0.0, m_encoderSim.getDistance(), 0.05);
+      assertEquals(0.0, encoderSim.getDistance(), 0.05);
     }
 
     {
       // Press button to reach setpoint
-      m_joystickSim.setTrigger(true);
-      m_joystickSim.notifyNewData();
+      joystickSim.setTrigger(true);
+      joystickSim.notifyNewData();
 
       // advance 75 timesteps
       SimHooks.stepTiming(1.5);
 
-      assertEquals(Constants.kSetpoint, m_encoderSim.getDistance(), 0.05);
+      assertEquals(Constants.kSetpoint, encoderSim.getDistance(), 0.05);
 
       // advance 25 timesteps to see setpoint is held.
       SimHooks.stepTiming(0.5);
 
-      assertEquals(Constants.kSetpoint, m_encoderSim.getDistance(), 0.05);
+      assertEquals(Constants.kSetpoint, encoderSim.getDistance(), 0.05);
     }
 
     {
       // Unpress the button to go back down
-      m_joystickSim.setTrigger(false);
-      m_joystickSim.notifyNewData();
+      joystickSim.setTrigger(false);
+      joystickSim.notifyNewData();
 
       // advance 75 timesteps
       SimHooks.stepTiming(1.5);
 
-      assertEquals(0.0, m_encoderSim.getDistance(), 0.05);
+      assertEquals(0.0, encoderSim.getDistance(), 0.05);
     }
 
     {
       // Press button to go back up
-      m_joystickSim.setTrigger(true);
-      m_joystickSim.notifyNewData();
+      joystickSim.setTrigger(true);
+      joystickSim.notifyNewData();
 
       // advance 75 timesteps
       SimHooks.stepTiming(1.5);
 
-      assertEquals(Constants.kSetpoint, m_encoderSim.getDistance(), 0.05);
+      assertEquals(Constants.kSetpoint, encoderSim.getDistance(), 0.05);
 
       // advance 25 timesteps to see setpoint is held.
       SimHooks.stepTiming(0.5);
 
-      assertEquals(Constants.kSetpoint, m_encoderSim.getDistance(), 0.05);
+      assertEquals(Constants.kSetpoint, encoderSim.getDistance(), 0.05);
     }
 
     {
@@ -131,8 +131,8 @@ class ElevatorSimulationTest {
       // advance 75 timesteps
       SimHooks.stepTiming(1.5);
 
-      assertEquals(0.0, m_motorSim.getThrottle(), 0.05);
-      assertEquals(0.0, m_encoderSim.getDistance(), 0.05);
+      assertEquals(0.0, motorSim.getThrottle(), 0.05);
+      assertEquals(0.0, encoderSim.getDistance(), 0.05);
     }
   }
 }

wpilibjExamples/src/test/java/org/wpilib/examples/unittest/subsystems/IntakeTest.java

@@ -18,18 +18,18 @@ import org.wpilib.simulation.PWMMotorControllerSim;
 
 class IntakeTest {
   static final double DELTA = 1e-2; // acceptable deviation range
-  Intake m_intake;
-  PWMMotorControllerSim m_simMotor;
-  DoubleSolenoidSim m_simPiston;
+  Intake intake;
+  PWMMotorControllerSim simMotor;
+  DoubleSolenoidSim simPiston;
 
   @BeforeEach // this method will run before each test
   void setup() {
     assert HAL.initialize(500, 0); // initialize the HAL, crash if failed
-    m_intake = new Intake(); // create our intake
-    m_simMotor =
+    intake = new Intake(); // create our intake
+    simMotor =
         new PWMMotorControllerSim(
             IntakeConstants.kMotorPort); // create our simulation PWM motor controller
-    m_simPiston =
+    simPiston =
         new DoubleSolenoidSim(
             PneumaticsModuleType.CTRE_PCM,
             IntakeConstants.kPistonFwdChannel,
@@ -39,33 +39,33 @@ class IntakeTest {
   @SuppressWarnings("PMD.SignatureDeclareThrowsException")
   @AfterEach // this method will run after each test
   void shutdown() throws Exception {
-    m_intake.close(); // destroy our intake object
+    intake.close(); // destroy our intake object
   }
 
   @Test // marks this method as a test
   void doesntWorkWhenClosed() {
-    m_intake.retract(); // close the intake
-    m_intake.activate(0.5); // try to activate the motor
+    intake.retract(); // close the intake
+    intake.activate(0.5); // try to activate the motor
     assertEquals(
-        0.0, m_simMotor.getThrottle(), DELTA); // make sure that the value set to the motor is 0
+        0.0, simMotor.getThrottle(), DELTA); // make sure that the value set to the motor is 0
   }
 
   @Test
   void worksWhenOpen() {
-    m_intake.deploy();
-    m_intake.activate(0.5);
-    assertEquals(0.5, m_simMotor.getThrottle(), DELTA);
+    intake.deploy();
+    intake.activate(0.5);
+    assertEquals(0.5, simMotor.getThrottle(), DELTA);
   }
 
   @Test
   void retractTest() {
-    m_intake.retract();
-    assertEquals(DoubleSolenoid.Value.REVERSE, m_simPiston.get());
+    intake.retract();
+    assertEquals(DoubleSolenoid.Value.REVERSE, simPiston.get());
   }
 
   @Test
   void deployTest() {
-    m_intake.deploy();
-    assertEquals(DoubleSolenoid.Value.FORWARD, m_simPiston.get());
+    intake.deploy();
+    assertEquals(DoubleSolenoid.Value.FORWARD, simPiston.get());
   }
 }

wpilibjExamples/src/test/java/org/wpilib/snippets/digitalcommunication/DigitalCommunicationTest.java

@@ -23,12 +23,12 @@ import org.wpilib.simulation.SimHooks;
 
 @ResourceLock("timing")
 class DigitalCommunicationTest {
-  private Robot m_robot;
-  private Thread m_thread;
-  private final DIOSim m_allianceOutput = new DIOSim(Robot.kAlliancePort);
-  private final DIOSim m_enabledOutput = new DIOSim(Robot.kEnabledPort);
-  private final DIOSim m_autonomousOutput = new DIOSim(Robot.kAutonomousPort);
-  private final DIOSim m_alertOutput = new DIOSim(Robot.kAlertPort);
+  private Robot robot;
+  private Thread thread;
+  private final DIOSim allianceOutput = new DIOSim(Robot.kAlliancePort);
+  private final DIOSim enabledOutput = new DIOSim(Robot.kEnabledPort);
+  private final DIOSim autonomousOutput = new DIOSim(Robot.kAutonomousPort);
+  private final DIOSim alertOutput = new DIOSim(Robot.kAlertPort);
 
   @BeforeEach
   void startThread() {
@@ -36,26 +36,26 @@ class DigitalCommunicationTest {
     SimHooks.pauseTiming();
     SimHooks.setProgramStarted(false);
     DriverStationSim.resetData();
-    m_robot = new Robot();
-    m_thread = new Thread(m_robot::startCompetition);
-    m_thread.start();
+    robot = new Robot();
+    thread = new Thread(robot::startCompetition);
+    thread.start();
     SimHooks.waitForProgramStart();
   }
 
   @AfterEach
   void stopThread() {
-    m_robot.endCompetition();
+    robot.endCompetition();
     try {
-      m_thread.interrupt();
-      m_thread.join();
+      thread.interrupt();
+      thread.join();
     } catch (InterruptedException ex) {
       Thread.currentThread().interrupt();
     }
-    m_robot.close();
-    m_allianceOutput.resetData();
-    m_enabledOutput.resetData();
-    m_autonomousOutput.resetData();
-    m_alertOutput.resetData();
+    robot.close();
+    allianceOutput.resetData();
+    enabledOutput.resetData();
+    autonomousOutput.resetData();
+    alertOutput.resetData();
   }
 
   @EnumSource(AllianceStationID.class)
@@ -64,12 +64,12 @@ class DigitalCommunicationTest {
     DriverStationSim.setAllianceStationId(alliance);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_allianceOutput.getInitialized());
-    assertFalse(m_allianceOutput.getIsInput());
+    assertTrue(allianceOutput.getInitialized());
+    assertFalse(allianceOutput.getIsInput());
 
     SimHooks.stepTiming(0.02);
 
-    assertEquals(alliance.name().startsWith("RED"), m_allianceOutput.getValue());
+    assertEquals(alliance.name().startsWith("RED"), allianceOutput.getValue());
   }
 
   @ValueSource(booleans = {true, false})
@@ -78,12 +78,12 @@ class DigitalCommunicationTest {
     DriverStationSim.setEnabled(enabled);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_enabledOutput.getInitialized());
-    assertFalse(m_enabledOutput.getIsInput());
+    assertTrue(enabledOutput.getInitialized());
+    assertFalse(enabledOutput.getIsInput());
 
     SimHooks.stepTiming(0.02);
 
-    assertEquals(enabled, m_enabledOutput.getValue());
+    assertEquals(enabled, enabledOutput.getValue());
   }
 
   @ValueSource(booleans = {true, false})
@@ -92,12 +92,12 @@ class DigitalCommunicationTest {
     DriverStationSim.setRobotMode(autonomous ? RobotMode.AUTONOMOUS : RobotMode.TELEOPERATED);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_autonomousOutput.getInitialized());
-    assertFalse(m_autonomousOutput.getIsInput());
+    assertTrue(autonomousOutput.getInitialized());
+    assertFalse(autonomousOutput.getIsInput());
 
     SimHooks.stepTiming(0.02);
 
-    assertEquals(autonomous, m_autonomousOutput.getValue());
+    assertEquals(autonomous, autonomousOutput.getValue());
   }
 
   @ValueSource(doubles = {45.0, 27.0, 23.0})
@@ -106,11 +106,11 @@ class DigitalCommunicationTest {
     DriverStationSim.setMatchTime(matchTime);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_alertOutput.getInitialized());
-    assertFalse(m_alertOutput.getIsInput());
+    assertTrue(alertOutput.getInitialized());
+    assertFalse(alertOutput.getIsInput());
 
     SimHooks.stepTiming(0.02);
 
-    assertEquals(matchTime <= 30 && matchTime >= 25, m_alertOutput.getValue());
+    assertEquals(matchTime <= 30 && matchTime >= 25, alertOutput.getValue());
   }
 }

wpilibjExamples/src/test/java/org/wpilib/snippets/i2ccommunication/I2CCommunicationTest.java

@@ -28,11 +28,11 @@ import org.wpilib.simulation.SimHooks;
 
 @ResourceLock("timing")
 class I2CCommunicationTest {
-  private Robot m_robot;
-  private Thread m_thread;
-  private final I2CSim m_i2c = new I2CSim(Robot.kPort.value);
-  private CompletableFuture<String> m_future;
-  private CallbackStore m_callback;
+  private Robot robot;
+  private Thread thread;
+  private final I2CSim i2c = new I2CSim(Robot.kPort.value);
+  private CompletableFuture<String> future;
+  private CallbackStore callback;
 
   @BeforeEach
   void startThread() {
@@ -40,29 +40,29 @@ class I2CCommunicationTest {
     SimHooks.pauseTiming();
     SimHooks.setProgramStarted(false);
     DriverStationSim.resetData();
-    m_future = new CompletableFuture<>();
-    m_callback =
-        m_i2c.registerWriteCallback(
+    future = new CompletableFuture<>();
+    callback =
+        i2c.registerWriteCallback(
             (name, buffer, count) ->
-                m_future.complete(new String(buffer, 0, count, StandardCharsets.UTF_8)));
-    m_robot = new Robot();
-    m_thread = new Thread(m_robot::startCompetition);
-    m_thread.start();
+                future.complete(new String(buffer, 0, count, StandardCharsets.UTF_8)));
+    robot = new Robot();
+    thread = new Thread(robot::startCompetition);
+    thread.start();
     SimHooks.waitForProgramStart();
   }
 
   @AfterEach
   void stopThread() {
-    m_robot.endCompetition();
+    robot.endCompetition();
     try {
-      m_thread.interrupt();
-      m_thread.join();
+      thread.interrupt();
+      thread.join();
     } catch (InterruptedException ex) {
       Thread.currentThread().interrupt();
     }
-    m_robot.close();
-    m_callback.close();
-    m_i2c.resetData();
+    robot.close();
+    callback.close();
+    i2c.resetData();
   }
 
   @EnumSource(AllianceStationID.class)
@@ -71,11 +71,11 @@ class I2CCommunicationTest {
     DriverStationSim.setAllianceStationId(alliance);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_i2c.getInitialized());
+    assertTrue(i2c.getInitialized());
 
     SimHooks.stepTiming(0.02);
 
-    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> m_future.get());
+    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> future.get());
     char expected = alliance.name().startsWith("RED") ? 'R' : 'B';
     if (alliance.name().startsWith("UNKNOWN")) {
       expected = 'U';
@@ -90,11 +90,11 @@ class I2CCommunicationTest {
     DriverStationSim.setEnabled(enabled);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_i2c.getInitialized());
+    assertTrue(i2c.getInitialized());
 
     SimHooks.stepTiming(0.02);
 
-    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> m_future.get());
+    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> future.get());
     char expected = enabled ? 'E' : 'D';
 
     assertEquals(expected, str.charAt(1));
@@ -106,11 +106,11 @@ class I2CCommunicationTest {
     DriverStationSim.setRobotMode(autonomous ? RobotMode.AUTONOMOUS : RobotMode.TELEOPERATED);
     DriverStationSim.notifyNewData();
 
-    assertTrue(m_i2c.getInitialized());
+    assertTrue(i2c.getInitialized());
 
     SimHooks.stepTiming(0.02);
 
-    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> m_future.get());
+    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> future.get());
     char expected = autonomous ? 'A' : 'T';
 
     assertEquals(expected, str.charAt(2));
@@ -121,11 +121,11 @@ class I2CCommunicationTest {
   void matchTimeTest(double matchTime) {
     DriverStationSim.setMatchTime(matchTime);
     DriverStationSim.notifyNewData();
-    assertTrue(m_i2c.getInitialized());
+    assertTrue(i2c.getInitialized());
 
     SimHooks.stepTiming(0.02);
 
-    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> m_future.get());
+    String str = assertTimeoutPreemptively(Duration.ofMillis(20L), () -> future.get());
     String expected = String.format("%03d", (int) MatchState.getMatchTime());
 
     assertEquals(expected, str.substring(3));