Add a unit test

Author: AndyZe

src/xml_parsing.cpp

@@ -548,7 +548,7 @@ void VerifyXML(const std::string& xml_text,
           auto child_type = child_search->second;
           if(child_type == NodeType::CONTROL &&
              ((child_name == "ThreadedAction") || (child_name == "StatefulActionNode") ||
-              (child_name == "CoroActionNode")))
+              (child_name == "CoroActionNode") || (child_name == "AsyncSequence")))
           {
             ThrowError(line_number, std::string("The first child of a ReactiveSequence "
                                                 "cannot be asynchronous"));

tests/gtest_reactive.cpp

@@ -156,3 +156,31 @@ TEST(Reactive, TestLogging)
   ASSERT_EQ(observer.getStatistics("testA").success_count, num_ticks);
   ASSERT_EQ(observer.getStatistics("success").success_count, num_ticks);
 }
+
+TEST(Reactive, TwoAsyncNodesInReactiveSequence)
+{
+  static const char* reactive_xml_text = R"(
+<root BTCPP_format="4" >
+  <BehaviorTree ID="MainTree">
+    <ReactiveSequence>
+      <AsyncSequence name="first">
+        <TestA/>
+        <TestB/>
+        <TestC/>
+      </AsyncSequence>
+      <AsyncSequence name="second">
+        <TestD/>
+        <TestE/>
+        <TestF/>
+      </AsyncSequence>
+    </ReactiveSequence>
+  </BehaviorTree>
+</root>
+)";
+
+  BT::BehaviorTreeFactory factory;
+  std::array<int, 6> counters;
+  RegisterTestTick(factory, "Test", counters);
+
+  EXPECT_ANY_THROW(auto tree = factory.createTreeFromText(reactive_xml_text));
+}