fix input type deduction for default conversions (#59)

Author: Schmluk

config_utilities/include/config_utilities/internal/visitor.h

@@ -169,13 +169,15 @@ struct Visitor {
   // Dispatch populating field input info from conversions.
   template <typename Conversion,
             typename ConfigT,
+            typename IntermediateT,
             typename std::enable_if<!hasFieldInputInfo<Conversion>() || isConfig<ConfigT>(), bool>::type = true>
-  static void getFieldInputInfo(const std::string& field_name);
+  static void getFieldInputInfo(const IntermediateT& intermediate, const std::string& field_name);
 
   template <typename Conversion,
             typename ConfigT,
+            typename IntermediateT,
             typename std::enable_if<hasFieldInputInfo<Conversion>() && !isConfig<ConfigT>(), bool>::type = true>
-  static void getFieldInputInfo(const std::string& field_name);
+  static void getFieldInputInfo(const IntermediateT& intermediate, const std::string& field_name);
 
   // Computes the default values for all fields in the meta data. This assumes that the meta data is already created,
   // and the meta data was created from ConfigT.

config_utilities/include/config_utilities/internal/visitor_impl.hpp

@@ -211,14 +211,13 @@ void Visitor::visitField(T& field, const std::string& field_name, const std::str
     auto intermediate = Conversion::toIntermediate(field, error);
     if (!error.empty()) {
       visitor.data.errors.emplace_back(new Warning(field_name, error));
-      error.clear();
     }
 
     Visitor::visitField(intermediate, field_name, unit);
 
     // Get type information if requested.
     if (visitor.mode == Visitor::Mode::kGetInfo) {
-      Visitor::getFieldInputInfo<Conversion, T>(field_name);
+      Visitor::getFieldInputInfo<Conversion, T>(intermediate, field_name);
     }
   }
 }
@@ -457,8 +456,9 @@ void Visitor::getDefaultValues(const ConfigT& config, MetaData& data) {
 // intentional no-op
 template <typename Conversion,
           typename ConfigT,
+          typename IntermediateT,
           typename std::enable_if<!hasFieldInputInfo<Conversion>() || isConfig<ConfigT>(), bool>::type>
-void Visitor::getFieldInputInfo(const std::string& field_name) {
+void Visitor::getFieldInputInfo(const IntermediateT&, const std::string& field_name) {
   static_assert(!isConfig<ConfigT>() || !hasFieldInputInfo<Conversion>(),
                 "Config types (with declare_config) cannot have field input information!");
 
@@ -471,14 +471,18 @@ void Visitor::getFieldInputInfo(const std::string& field_name) {
     visitor.data.errors.emplace_back(
         new Warning(field_name, "Invalid parsing state! Field info should already exist!"));
   } else {
-    visitor.data.field_infos.back().input_info.reset();  // clear field input info for underlying intermediate type
+    // Default: Create the field input info of the intermediate type.
+    auto input_info = createFieldInputInfo<IntermediateT>();
+    auto& info = visitor.data.field_infos.back();
+    info.input_info = FieldInputInfo::merge(input_info, info.input_info);
   }
 }
 
 template <typename Conversion,
           typename ConfigT,
+          typename IntermediateT,
           typename std::enable_if<hasFieldInputInfo<Conversion>() && !isConfig<ConfigT>(), bool>::type>
-void Visitor::getFieldInputInfo(const std::string& field_name) {
+void Visitor::getFieldInputInfo(const IntermediateT&, const std::string& field_name) {
   auto input_info = Conversion::getFieldInputInfo();
 
   auto& visitor = Visitor::instance();

config_utilities/test/tests/conversions.cpp

@@ -243,8 +243,10 @@ TEST(Conversions, FieldInputInfo) {
   ConversionStruct without_info;
   data = internal::Visitor::getInfo(without_info);
   EXPECT_EQ(data.field_infos.size(), 2);
-  EXPECT_FALSE(data.field_infos[0].input_info);
-  EXPECT_FALSE(data.field_infos[1].input_info);
+  EXPECT_TRUE(data.field_infos[0].input_info);
+  EXPECT_TRUE(data.field_infos[1].input_info);
+  EXPECT_EQ(data.field_infos[0].input_info->type, internal::FieldInputInfo::Type::kInt);     // num_threads
+  EXPECT_EQ(data.field_infos[1].input_info->type, internal::FieldInputInfo::Type::kString);  // some_character
 }
 
 TEST(Conversions, ConversionDeclareConfigDispatch) {

config_utilities_ros/config_utilities_ros/gui/dynamic_config_gui.py

@@ -314,6 +314,10 @@ def parse_rec(config, indent, prefix):
             prefix_str = "".join([f"{p}{NS_SEP}" for p in prefix])
             for field in config["fields"]:
                 if field["type"] == "field":
+                    # Default the input info to just strings if no details are present.
+                    if "input_info" not in field:
+                        field["input_info"] = {"type": "yaml"}
+
                     # Data for each field (leaves of the config).
                     field["id"] = f"{prefix_str}{field['name']}"
                     field["indent"] = indent