Split the two command implementations into separate libraries (#2012)

This will allow us at the user code side to determine to include old commands, new commands or both.

wpilibOldCommands/src/main/native/cpp/commands/Subsystem.cpp

@@ -0,0 +1,134 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2011-2019 FIRST. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "frc/commands/Subsystem.h"
+
+#include "frc/WPIErrors.h"
+#include "frc/commands/Command.h"
+#include "frc/commands/Scheduler.h"
+#include "frc/livewindow/LiveWindow.h"
+#include "frc/smartdashboard/SendableBuilder.h"
+#include "frc/smartdashboard/SendableRegistry.h"
+
+using namespace frc;
+
+Subsystem::Subsystem(const wpi::Twine& name) {
+  SendableRegistry::GetInstance().AddLW(this, name, name);
+  Scheduler::GetInstance()->RegisterSubsystem(this);
+}
+
+void Subsystem::SetDefaultCommand(Command* command) {
+  if (command == nullptr) {
+    m_defaultCommand = nullptr;
+  } else {
+    const auto& reqs = command->GetRequirements();
+    if (std::find(reqs.begin(), reqs.end(), this) == reqs.end()) {
+      wpi_setWPIErrorWithContext(
+          CommandIllegalUse, "A default command must require the subsystem");
+      return;
+    }
+
+    m_defaultCommand = command;
+  }
+}
+
+Command* Subsystem::GetDefaultCommand() {
+  if (!m_initializedDefaultCommand) {
+    m_initializedDefaultCommand = true;
+    InitDefaultCommand();
+  }
+  return m_defaultCommand;
+}
+
+wpi::StringRef Subsystem::GetDefaultCommandName() {
+  Command* defaultCommand = GetDefaultCommand();
+  if (defaultCommand) {
+    return SendableRegistry::GetInstance().GetName(defaultCommand);
+  } else {
+    return wpi::StringRef();
+  }
+}
+
+void Subsystem::SetCurrentCommand(Command* command) {
+  m_currentCommand = command;
+  m_currentCommandChanged = true;
+}
+
+Command* Subsystem::GetCurrentCommand() const { return m_currentCommand; }
+
+wpi::StringRef Subsystem::GetCurrentCommandName() const {
+  Command* currentCommand = GetCurrentCommand();
+  if (currentCommand) {
+    return SendableRegistry::GetInstance().GetName(currentCommand);
+  } else {
+    return wpi::StringRef();
+  }
+}
+
+void Subsystem::Periodic() {}
+
+void Subsystem::InitDefaultCommand() {}
+
+std::string Subsystem::GetName() const {
+  return SendableRegistry::GetInstance().GetName(this);
+}
+
+void Subsystem::SetName(const wpi::Twine& name) {
+  SendableRegistry::GetInstance().SetName(this, name);
+}
+
+std::string Subsystem::GetSubsystem() const {
+  return SendableRegistry::GetInstance().GetSubsystem(this);
+}
+
+void Subsystem::SetSubsystem(const wpi::Twine& name) {
+  SendableRegistry::GetInstance().SetSubsystem(this, name);
+}
+
+void Subsystem::AddChild(const wpi::Twine& name,
+                         std::shared_ptr<Sendable> child) {
+  AddChild(name, *child);
+}
+
+void Subsystem::AddChild(const wpi::Twine& name, Sendable* child) {
+  AddChild(name, *child);
+}
+
+void Subsystem::AddChild(const wpi::Twine& name, Sendable& child) {
+  auto& registry = SendableRegistry::GetInstance();
+  registry.AddLW(&child, registry.GetSubsystem(this), name);
+  registry.AddChild(this, &child);
+}
+
+void Subsystem::AddChild(std::shared_ptr<Sendable> child) { AddChild(*child); }
+
+void Subsystem::AddChild(Sendable* child) { AddChild(*child); }
+
+void Subsystem::AddChild(Sendable& child) {
+  auto& registry = SendableRegistry::GetInstance();
+  registry.SetSubsystem(&child, registry.GetSubsystem(this));
+  registry.EnableLiveWindow(&child);
+  registry.AddChild(this, &child);
+}
+
+void Subsystem::ConfirmCommand() {
+  if (m_currentCommandChanged) m_currentCommandChanged = false;
+}
+
+void Subsystem::InitSendable(SendableBuilder& builder) {
+  builder.SetSmartDashboardType("Subsystem");
+
+  builder.AddBooleanProperty(
+      ".hasDefault", [=]() { return m_defaultCommand != nullptr; }, nullptr);
+  builder.AddStringProperty(".default",
+                            [=]() { return GetDefaultCommandName(); }, nullptr);
+
+  builder.AddBooleanProperty(
+      ".hasCommand", [=]() { return m_currentCommand != nullptr; }, nullptr);
+  builder.AddStringProperty(".command",
+                            [=]() { return GetCurrentCommandName(); }, nullptr);
+}