[commands] Add static Trigger factories for robot mode changes

wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/button/GameTriggers.java

@@ -0,0 +1,52 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+package edu.wpi.first.wpilibj2.command.button;
+
+import edu.wpi.first.wpilibj.DriverStation;
+
+/**
+ * A class containing static {@link Trigger} factories for running callbacks when the robot mode
+ * changes.
+ */
+public final class GameTriggers {
+  // Utility class
+  private GameTriggers() {}
+
+  /**
+   * Returns a trigger that is true when the robot is enabled in autonomous mode.
+   *
+   * @return A trigger that is true when the robot is enabled in autonomous mode.
+   */
+  public static Trigger autonomous() {
+    return new Trigger(DriverStation::isAutonomousEnabled);
+  }
+
+  /**
+   * Returns a trigger that is true when the robot is enabled in teleop mode.
+   *
+   * @return A trigger that is true when the robot is enabled in teleop mode.
+   */
+  public static Trigger teleop() {
+    return new Trigger(DriverStation::isTeleopEnabled);
+  }
+
+  /**
+   * Returns a trigger that is true when the robot is disabled.
+   *
+   * @return A trigger that is true when the robot is disabled.
+   */
+  public static Trigger disabled() {
+    return new Trigger(DriverStation::isDisabled);
+  }
+
+  /**
+   * Returns a trigger that is true when the robot is enabled in test mode.
+   *
+   * @return A trigger that is true when the robot is enabled in test mode.
+   */
+  public static Trigger test() {
+    return new Trigger(DriverStation::isTestEnabled);
+  }
+}

wpilibNewCommands/src/main/native/cpp/frc2/command/button/GameTriggers.cpp

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+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "frc2/command/button/GameTriggers.h"
+
+#include <frc/DriverStation.h>
+
+using namespace frc2;
+
+Trigger GameTriggers::Autonomous() {
+  return Trigger{&frc::DriverStation::IsAutonomousEnabled};
+}
+
+Trigger GameTriggers::Teleop() {
+  return Trigger{&frc::DriverStation::IsTeleopEnabled};
+}
+
+Trigger GameTriggers::Disabled() {
+  return Trigger{&frc::DriverStation::IsDisabled};
+}
+
+Trigger GameTriggers::Test() {
+  return Trigger{&frc::DriverStation::IsTestEnabled};
+}

wpilibNewCommands/src/main/native/include/frc2/command/button/GameTriggers.h

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+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#pragma once
+
+#include "frc2/command/button/Trigger.h"
+
+namespace frc2 {
+
+/**
+ * A class containing static Trigger factories for running callbacks when robot
+ * mode changes.
+ */
+class GameTriggers {
+ public:
+  GameTriggers() = delete;
+
+  /**
+   * Returns a trigger that is true when the robot is enabled in autonomous
+   * mode.
+   *
+   * @return A trigger that is true when the robot is enabled in autonomous
+   * mode.
+   */
+  static Trigger Autonomous();
+
+  /**
+   * Returns a trigger that is true when the robot is enabled in teleop mode.
+   *
+   * @return A trigger that is true when the robot is enabled in teleop mode.
+   */
+  static Trigger Teleop();
+
+  /**
+   * Returns a trigger that is true when the robot is disabled.
+   *
+   * @return A trigger that is true when the robot is disabled.
+   */
+  static Trigger Disabled();
+
+  /**
+   * Returns a trigger that is true when the robot is enabled in test mode.
+   *
+   * @return A trigger that is true when the robot is enabled in test mode.
+   */
+  static Trigger Test();
+};
+
+}  // namespace frc2

wpilibNewCommands/src/test/java/edu/wpi/first/wpilibj2/command/button/GameTriggersTest.java

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+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+package edu.wpi.first.wpilibj2.command.button;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import edu.wpi.first.wpilibj.DriverStation;
+import edu.wpi.first.wpilibj.simulation.DriverStationSim;
+import edu.wpi.first.wpilibj2.command.CommandTestBase;
+import org.junit.jupiter.api.Test;
+
+class GameTriggersTest extends CommandTestBase {
+  @Test
+  void autonomousTest() {
+    Trigger auto = GameTriggers.autonomous();
+    DriverStationSim.setAutonomous(true);
+    DriverStation.refreshData();
+    assertTrue(auto.getAsBoolean());
+  }
+}