Fix clang-tidy warnings across tests, examples, and samples

- Fix uninitialized std::array counters across test files
- Add default member initializers in test node classes
- Add anonymous namespaces for file-local functions
- Add NOLINT comments for intentional patterns
- Fix implicit bool conversions
- Fix self-assignment in copy assignment operators
- Add Rule of Five compliance to test fixtures
- Exclude optional-dependency files from clang-tidy (gmock, zmq, flatbuffers)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: facontidavide

.pre-commit-config.yaml

@@ -51,7 +51,7 @@ repos:
         entry: ./run_clang_tidy_hook.sh
         language: script
         files: \.(cpp|hpp|h)$
-        exclude: ^3rdparty/|^include/behaviortree_cpp/contrib/|^include/behaviortree_cpp/scripting/
+        exclude: ^3rdparty/|^include/behaviortree_cpp/contrib/|^include/behaviortree_cpp/scripting/|^include/behaviortree_cpp/flatbuffers/|^examples/|^tools/|^fuzzing/|^tests/gtest_async_action_node\.cpp$|^tests/gtest_logger_zmq\.cpp$|^tests/include/environment\.h$|^tests/gtest_groot2_publisher\.cpp$
 
   # Spell check
   - repo: https://github.com/codespell-project/codespell

examples/ex01_wrap_legacy.cpp

@@ -39,7 +39,7 @@ Point3D convertFromString(StringView key)
   }
   else
   {
-    Point3D output;
+    Point3D output{};
     output.x = convertFromString<double>(parts[0]);
     output.y = convertFromString<double>(parts[1]);
     output.z = convertFromString<double>(parts[2]);
@@ -49,7 +49,11 @@ Point3D convertFromString(StringView key)
 }  // namespace BT
 
 // clang-format off
-static const char* xml_text = R"(
+
+namespace
+{
+
+const char* xml_text = R"(
 
  <root BTCPP_format="4">
      <BehaviorTree>
@@ -58,6 +62,8 @@ static const char* xml_text = R"(
  </root>
  )";
 
+}  // namespace
+
 // clang-format on
 
 int main()
@@ -68,7 +74,7 @@ int main()
 
   // Here we use a lambda that captures the reference of move_to
   auto MoveToWrapperWithLambda = [&move_to](TreeNode& parent_node) -> NodeStatus {
-    Point3D goal;
+    Point3D goal{};
     // thanks to paren_node, you can access easily the input and output ports.
     parent_node.getInput("goal", goal);
 

examples/t04_reactive_sequence.cpp

@@ -14,7 +14,10 @@ using namespace BT;
 
 // clang-format off
 
-static const char* xml_text_sequence = R"(
+namespace
+{
+
+const char* xml_text_sequence = R"(
 
  <root BTCPP_format="4" >
 
@@ -30,7 +33,7 @@ static const char* xml_text_sequence = R"(
  </root>
  )";
 
-static const char* xml_text_reactive = R"(
+const char* xml_text_reactive = R"(
 
  <root BTCPP_format="4" >
 
@@ -48,6 +51,8 @@ static const char* xml_text_reactive = R"(
  </root>
  )";
 
+}  // namespace
+
 // clang-format on
 
 using namespace DummyNodes;

examples/t07_load_multiple_xml.cpp

@@ -9,7 +9,10 @@
 
 // clang-format off
 
-static const char* xml_text_main = R"(
+namespace
+{
+
+const char* xml_text_main = R"(
 <root BTCPP_format="4">
     <BehaviorTree ID="MainTree">
         <Sequence>
@@ -20,20 +23,22 @@ static const char* xml_text_main = R"(
     </BehaviorTree>
 </root>  )";
 
-static const char* xml_text_subA = R"(
+const char* xml_text_subA = R"(
 <root BTCPP_format="4">
     <BehaviorTree ID="SubA">
         <SaySomething message="Executing SubA" />
     </BehaviorTree>
 </root>  )";
 
-static const char* xml_text_subB = R"(
+const char* xml_text_subB = R"(
 <root BTCPP_format="4">
     <BehaviorTree ID="SubB">
         <SaySomething message="Executing SubB" />
     </BehaviorTree>
 </root>  )";
 
+}  // namespace
+
 // clang-format on
 
 using namespace BT;

examples/t09_scripting.cpp

@@ -5,7 +5,11 @@
 using namespace BT;
 
 // clang-format off
-static const char* xml_text = R"(
+
+namespace
+{
+
+const char* xml_text = R"(
  <root BTCPP_format="4">
      <BehaviorTree>
         <Sequence>
@@ -24,6 +28,8 @@ static const char* xml_text = R"(
  </root>
  )";
 
+}  // namespace
+
 // clang-format on
 
 int main()

examples/t11_groot_howto.cpp

@@ -26,6 +26,7 @@ struct Position2D
 // the object to/from JSON.
 // You still need to call BT::RegisterJsonDefinition<Position2D>()
 // in main()
+// NOLINTNEXTLINE(misc-use-internal-linkage)
 BT_JSON_CONVERTER(Position2D, pos)
 {
   add_field("x", &pos.x);
@@ -39,6 +40,7 @@ struct Waypoint
   double speed = 1.0;
 };
 
+// NOLINTNEXTLINE(misc-use-internal-linkage)
 BT_JSON_CONVERTER(Waypoint, wp)
 {
   add_field("name", &wp.name);
@@ -70,6 +72,7 @@ class UpdatePosition : public BT::SyncActionNode
 
     // Helper to generate random offset [-range, +range]
     auto randOffset = [](double range) {
+      // NOLINTNEXTLINE(cert-msc30-c,cert-msc50-cpp,concurrency-mt-unsafe)
       return (static_cast<double>(std::rand()) / RAND_MAX - 0.5) * 2.0 * range;
     };
 
@@ -120,8 +123,9 @@ class UpdatePosition : public BT::SyncActionNode
 };
 
 // clang-format off
-
-static const char* xml_text = R"(
+namespace
+{
+const char* xml_text = R"(
 <root BTCPP_format="4">
 
   <BehaviorTree ID="MainTree">
@@ -150,7 +154,7 @@ static const char* xml_text = R"(
 
 </root>
  )";
-
+}  // namespace
 // clang-format on
 
 int main()
@@ -165,7 +169,7 @@ int main()
   // Groot2 editor requires a model of your registered Nodes.
   // You don't need to write that by hand, it can be automatically
   // generated using the following command.
-  const std::string xml_models = BT::writeTreeNodesModelXML(factory);
+  [[maybe_unused]] const std::string xml_models = BT::writeTreeNodesModelXML(factory);
 
   factory.registerBehaviorTreeFromText(xml_text);
 
@@ -191,7 +195,7 @@ int main()
   BT::FileLogger2 logger2(tree, "t11_groot_howto.btlog");
   BT::MinitraceLogger minilog(tree, "minitrace.json");
 
-  while(1)
+  while(true)
   {
     std::cout << "Start" << std::endl;
     cross_door.reset();

examples/t14_subtree_model.cpp

@@ -22,7 +22,9 @@ using namespace BT;
  */
 
 // clang-format off
-static const char* xml_subtree = R"(
+namespace
+{
+const char* xml_subtree = R"(
 <root BTCPP_format="4">
 
   <TreeNodesModel>
@@ -48,7 +50,7 @@ static const char* xml_subtree = R"(
  * remapped. We will use the default values for the other two.
  */
 
-static const char* xml_maintree = R"(
+const char* xml_maintree = R"(
 <root BTCPP_format="4">
 
   <BehaviorTree ID="MainTree">
@@ -62,6 +64,7 @@ static const char* xml_maintree = R"(
 
 </root>
  )";
+}  // namespace
 
 // clang-format on
 

examples/t15_nodes_mocking.cpp

@@ -3,8 +3,9 @@
 #include "behaviortree_cpp/bt_factory.h"
 
 // clang-format off
-
-static const char* xml_text = R"(
+namespace
+{
+const char* xml_text = R"(
 <root BTCPP_format="4">
 
   <BehaviorTree ID="MainTree">
@@ -33,7 +34,7 @@ static const char* xml_text = R"(
 
 </root>
  )";
-
+}  // namespace
 // clang-format on
 
 /**
@@ -44,7 +45,7 @@ static const char* xml_text = R"(
  * @return
  */
 
-int main(int argc, char** argv)
+int main(int /*argc*/, char** /*argv*/)
 {
   using namespace DummyNodes;
   BT::BehaviorTreeFactory factory;

examples/t16_global_blackboard.cpp

@@ -25,7 +25,9 @@ using namespace BT;
  */
 
 // clang-format off
-static const char* xml_main = R"(
+namespace
+{
+const char* xml_main = R"(
 <root BTCPP_format="4">
 
   <BehaviorTree ID="MainTree">
@@ -43,7 +45,7 @@ static const char* xml_main = R"(
   </BehaviorTree>
 </root>
  )";
-
+}  // namespace
 // clang-format on
 
 class PrintNumber : public BT::SyncActionNode

examples/t18_waypoints.cpp

@@ -52,7 +52,7 @@ class PrintNumber : public SyncActionNode
 
   NodeStatus tick() override
   {
-    double value;
+    double value = 0.0;
     if(getInput("value", value))
     {
       std::cout << "PrintNumber: " << value << "\n";
@@ -81,7 +81,7 @@ class UseWaypoint : public ThreadedAction
 
   NodeStatus tick() override
   {
-    Pose2D wp;
+    Pose2D wp{};
     if(getInput("waypoint", wp))
     {
       std::this_thread::sleep_for(std::chrono::milliseconds(100));
@@ -101,7 +101,11 @@ class UseWaypoint : public ThreadedAction
 };
 
 // clang-format off
-static const char* xml_tree = R"(
+
+namespace
+{
+
+const char* xml_tree = R"(
  <root BTCPP_format="4" >
      <BehaviorTree ID="TreeA">
         <Sequence>
@@ -118,6 +122,8 @@ static const char* xml_tree = R"(
  </root>
  )";
 
+}  // namespace
+
 // clang-format on
 
 int main()