fix issue #605: strip whitespaces and better error message

Author: facontidavide

include/behaviortree_cpp/basic_types.h

@@ -263,17 +263,21 @@ class PortInfo
   };
 
   PortInfo(PortDirection direction = PortDirection::INOUT) :
-    type_(direction), type_info_(typeid(AnyTypeAllowed))
+    type_(direction), type_info_(typeid(AnyTypeAllowed)),
+    type_str_("AnyTypeAllowed")
   {}
 
   PortInfo(PortDirection direction, std::type_index type_info, StringConverter conv) :
-    type_(direction), type_info_(type_info), converter_(conv)
+    type_(direction), type_info_(type_info), converter_(conv), 
+    type_str_(BT::demangle(type_info))
   {}
 
   [[nodiscard]] PortDirection direction() const;
 
   [[nodiscard]] const std::type_index& type() const;
 
+  [[nodiscard]] const std::string& typeName() const;
+
   [[nodiscard]] Any parseString(const char* str) const;
 
   [[nodiscard]] Any parseString(const std::string& str) const;
@@ -319,6 +323,7 @@ class PortInfo
   std::string description_;
   Any default_value_;
   std::string default_value_str_;
+  std::string type_str_;
 };
 
 template <typename T = PortInfo::AnyTypeAllowed> [[nodiscard]]

include/behaviortree_cpp/scripting/operators.hpp

@@ -479,7 +479,8 @@ struct ExprAssignment : ExprBase
         // fail otherwise
         auto msg = StrCat("The blackboard entry [", key,
                           "] doesn't exist, yet.\n"
-                          "If you want to create a new one, use the operator "
+                          "If you want to create a new one, "
+                          "use the operator "
                           "[:=] instead of [=]");
         throw RuntimeError(msg);
       }
@@ -531,11 +532,12 @@ struct ExprAssignment : ExprBase
         {
           value.copyInto(*dst_ptr);
         }
-        catch (RuntimeError&)
+        catch (std::exception&)
         {
           auto msg = StrCat(errorPrefix(), "\nThe right operand has type [",
                             BT::demangle(value.type()),
-                            "] and can't be converted");
+                            "] and can't be converted to [",
+                            BT::demangle(dst_ptr->type()), "]");
           throw RuntimeError(msg);
         }
       }

include/behaviortree_cpp/tree_node.h

@@ -284,10 +284,9 @@ class TreeNode
   // in the port (no remapping and no conversion to a type)
   [[nodiscard]] StringView getRawPortValue(const std::string& key) const;
 
-  /// Check a string and return true if it matches either one of these
-  /// two patterns:  {...} or ${...}
+  /// Check a string and return true if it matches the pattern:  {...}
   [[nodiscard]]
-  static bool isBlackboardPointer(StringView str);
+  static bool isBlackboardPointer(StringView str, StringView* stripped_pointer = nullptr);
 
   [[nodiscard]]
   static StringView stripBlackboardPointer(StringView str);

src/basic_types.cpp

@@ -335,6 +335,11 @@ const std::type_index& PortInfo::type() const
   return type_info_;
 }
 
+const std::string &PortInfo::typeName() const
+{
+  return type_str_;
+}
+
 Any PortInfo::parseString(const char* str) const
 {
   if (converter_)

src/tree_node.cpp

@@ -346,36 +346,38 @@ StringView TreeNode::getRawPortValue(const std::string& key) const
   return remap_it->second;
 }
 
-bool TreeNode::isBlackboardPointer(StringView str)
+bool TreeNode::isBlackboardPointer(StringView str, StringView* stripped_pointer)
 {
-  const auto size = str.size();
-  if (size >= 3 && str.back() == '}')
+  if (str.size() < 3)
   {
-    if (str[0] == '{')
-    {
-      return true;
-    }
-    if (size >= 4 && str[0] == '$' && str[1] == '{')
-    {
-      return true;
-    }
+    return false;
+  }
+  // strip leading and following spaces
+  size_t front_index = 0;
+  size_t last_index = str.size()-1;
+  while(str[front_index] == ' ' && front_index <= last_index)
+  {
+    front_index++;
+  }
+  while(str[last_index] == ' ' && front_index <= last_index)
+  {
+    last_index--;
+  }
+  const auto size = (last_index-front_index) + 1;
+  auto valid = size >= 3 && str[front_index] == '{' && str[last_index] == '}';
+  if(valid && stripped_pointer)
+  {
+    *stripped_pointer = StringView( &str[front_index+1], size-2);
   }
-  return false;
+  return valid;
 }
 
 StringView TreeNode::stripBlackboardPointer(StringView str)
 {
-  const auto size = str.size();
-  if (size >= 3 && str.back() == '}')
+  StringView out;
+  if(isBlackboardPointer(str, &out))
   {
-    if (str[0] == '{')
-    {
-      return str.substr(1, size - 2);
-    }
-    if (str[0] == '$' && str[1] == '{')
-    {
-      return str.substr(2, size - 3);
-    }
+    return out;
   }
   return {};
 }
@@ -387,9 +389,10 @@ Expected<StringView> TreeNode::getRemappedKey(StringView port_name,
   {
     return {port_name};
   }
-  if (isBlackboardPointer(remapped_port))
+  StringView stripped;
+  if (isBlackboardPointer(remapped_port, &stripped))
   {
-    return {stripBlackboardPointer(remapped_port)};
+    return {stripped};
   }
   return nonstd::make_unexpected("Not a blackboard pointer");
 }

tests/gtest_blackboard.cpp

@@ -360,3 +360,34 @@ TEST(BlackboardTest, SetStringView)
 
   ASSERT_NO_THROW(bb->set("string_view", string_view_const));
 }
+
+TEST(ParserTest, Issue605_whitespaces)
+{
+  BT::BehaviorTreeFactory factory;
+
+  const std::string xml_text = R"(
+  <root BTCPP_format="4" >
+    <BehaviorTree ID="MySubtree">
+      <Script code=" sub_value:=false " />
+    </BehaviorTree>
+
+    <BehaviorTree ID="MyMainTree">
+      <Sequence>
+        <Script code=" my_value:=true " />
+        <SubTree ID="MySubtree" sub_value="{my_value}  "/>
+      </Sequence>
+    </BehaviorTree>
+  </root> )";
+
+  factory.registerBehaviorTreeFromText(xml_text);
+  auto tree = factory.createTree("MyMainTree");
+  const auto status = tree.tickWhileRunning();
+
+  for(auto const& subtree: tree.subtrees)
+  {
+    subtree->blackboard->debugMessage();
+  }
+
+  ASSERT_EQ(status, BT::NodeStatus::SUCCESS);
+  ASSERT_EQ(false, tree.rootBlackboard()->get<bool>("my_value"));
+}