From e506e09a060ade64d63d5c60f8a731a1e29a3fd3 Mon Sep 17 00:00:00 2001
From: Joseph Eng <91924258+KangarooKoala@users.noreply.github.com>
Date: Sat, 10 Feb 2024 10:42:53 -0800
Subject: [PATCH] [wpilibc] Const-qualify SendableChooser::GetSelected()
 (#6356)

---
 .../native/include/frc/smartdashboard/SendableChooser.h    | 4 +++-
 .../native/include/frc/smartdashboard/SendableChooser.inc  | 7 +++----
 .../include/frc/smartdashboard/SendableChooserBase.h       | 2 +-
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.h b/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.h
index 2ca15160d7..0c17fdefe9 100644
--- a/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.h
+++ b/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.h
@@ -40,6 +40,8 @@ class SendableChooser : public SendableChooserBase {
   static std::weak_ptr<U> _unwrap_smart_ptr(const std::shared_ptr<U>& value);
 
  public:
+  using CopyType = decltype(_unwrap_smart_ptr(m_choices.lookup("")));
+
   SendableChooser() = default;
   ~SendableChooser() override = default;
   SendableChooser(SendableChooser&& rhs) = default;
@@ -78,7 +80,7 @@ class SendableChooser : public SendableChooserBase {
    *
    * @return The option selected
    */
-  auto GetSelected() -> decltype(_unwrap_smart_ptr(m_choices[""]));
+  CopyType GetSelected() const;
 
   /**
    * Bind a listener that's called when the selected value changes.
diff --git a/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.inc b/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.inc
index 57f4a1d118..2b93629959 100644
--- a/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.inc
+++ b/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooser.inc
@@ -33,8 +33,7 @@ void SendableChooser<T>::SetDefaultOption(std::string_view name, T object) {
 
 template <class T>
   requires std::copy_constructible<T> && std::default_initializable<T>
-auto SendableChooser<T>::GetSelected()
-    -> decltype(_unwrap_smart_ptr(m_choices[""])) {
+typename SendableChooser<T>::CopyType SendableChooser<T>::GetSelected() const {
   std::string selected = m_defaultChoice;
   {
     std::scoped_lock lock(m_mutex);
@@ -43,9 +42,9 @@ auto SendableChooser<T>::GetSelected()
     }
   }
   if (selected.empty()) {
-    return decltype(_unwrap_smart_ptr(m_choices[""])){};
+    return CopyType{};
   } else {
-    return _unwrap_smart_ptr(m_choices[selected]);
+    return _unwrap_smart_ptr(m_choices.lookup(selected));
   }
 }
 
diff --git a/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooserBase.h b/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooserBase.h
index f0b4fedcbb..3263f92f6b 100644
--- a/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooserBase.h
+++ b/wpilibc/src/main/native/include/frc/smartdashboard/SendableChooserBase.h
@@ -38,7 +38,7 @@ class SendableChooserBase : public wpi::Sendable,
   std::string m_defaultChoice;
   std::string m_selected;
   bool m_haveSelected = false;
-  wpi::mutex m_mutex;
+  mutable wpi::mutex m_mutex;
   int m_instance;
   std::string m_previousVal;
   static std::atomic_int s_instances;