[command] Rename PerpetualCommand to EndlessCommand (#4177)

wpilibNewCommands/src/main/native/include/frc2/command/EndlessCommand.h

@@ -0,0 +1,79 @@
+// 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
+
+#ifdef _WIN32
+#pragma warning(push)
+#pragma warning(disable : 4521)
+#endif
+
+#include <memory>
+#include <utility>
+
+#include "frc2/command/CommandBase.h"
+#include "frc2/command/CommandGroupBase.h"
+#include "frc2/command/CommandHelper.h"
+
+namespace frc2 {
+/**
+ * A command that runs another command endlessly, ignoring that command's
+ * end conditions.  While this class does not extend {@link CommandGroupBase},
+ * it is still considered a CommandGroup, as it allows one to compose another
+ * command within it; the command instances that are passed to it cannot be
+ * added to any other groups, or scheduled individually.
+ *
+ * <p>As a rule, CommandGroups require the union of the requirements of their
+ * component commands.
+ *
+ * This class is provided by the NewCommands VendorDep
+ */
+class EndlessCommand : public CommandHelper<CommandBase, EndlessCommand> {
+ public:
+  /**
+   * Creates a new EndlessCommand. Will run another command endlessly,
+   * ignoring that command's end conditions, unless this command itself is
+   * interrupted.
+   *
+   * @param command the command to run endlessly
+   */
+  explicit EndlessCommand(std::unique_ptr<Command>&& command);
+
+  /**
+   * Creates a new EndlessCommand. Will run another command endlessly,
+   * ignoring that command's end conditions, unless this command itself is
+   * interrupted.
+   *
+   * @param command the command to run endlessly
+   */
+  template <class T, typename = std::enable_if_t<std::is_base_of_v<
+                         Command, std::remove_reference_t<T>>>>
+  explicit EndlessCommand(T&& command)
+      : EndlessCommand(std::make_unique<std::remove_reference_t<T>>(
+            std::forward<T>(command))) {}
+
+  EndlessCommand(EndlessCommand&& other) = default;
+
+  // No copy constructors for command groups
+  EndlessCommand(const EndlessCommand& other) = delete;
+
+  // Prevent template expansion from emulating copy ctor
+  EndlessCommand(EndlessCommand&) = delete;
+
+  void Initialize() override;
+
+  void Execute() override;
+
+  void End(bool interrupted) override;
+
+  EndlessCommand Endlessly() && override;
+
+ private:
+  std::unique_ptr<Command> m_command;
+};
+}  // namespace frc2
+
+#ifdef _WIN32
+#pragma warning(pop)
+#endif