Use ordered map in DataTree to avoid extra sorting

Author: zykure

include/gul17/DataTree.h

@@ -23,9 +23,9 @@
 #ifndef GUL17_DATA_TREE_H_
 #define GUL17_DATA_TREE_H_
 
+#include <map>
 #include <stdexcept>
 #include <string>
-#include <unordered_map>
 #include <variant>
 #include <vector>
 
@@ -68,7 +68,7 @@ class DataTree
     // Type definitions
 
     /// Type of an object (key-value pairs)
-    using Object = std::unordered_map<std::string, DataTree>;
+    using Object = std::map<std::string, DataTree>;
     /// Type of an array (list of values)
     using Array = std::vector<DataTree>;
     /// Underlying variant type to hold different data types

src/data_processors/json_processor.cc

@@ -439,23 +439,15 @@ struct JsonDataSerializer
         output_ << "{";
         if (!obj.empty())
         {
-            // Sort keys for consistent output
-            std::vector<DataTree::Object::key_type> keys;
-            std::transform(obj.begin(), obj.end(), std::back_inserter(keys),
-                           [](const auto& pair) { return pair.first; });
-            std::sort(keys.begin(), keys.end());
-
             output_ << newline;
-            for (size_t i = 0; i < keys.size(); ++i)
+            size_t i = 0;
+            for (const auto & [key, val] : obj)
             {
-                const auto& key = keys[i];
-                const auto& val = obj.at(key);
-
                 output_ << std::string(current_indent + indent, ' ');
                 output_ << "\"" << escape_string(key) << "\": ";
                 serialize_value(val, indent, current_indent + indent);
 
-                if (i < keys.size() - 1)
+                if (i++ < obj.size() - 1)
                     output_ << ",";
                 output_ << newline;
             }

src/data_processors/xml_processor.cc

@@ -139,7 +139,7 @@ struct XmlDataParser
         if (!attributes.empty() || !children.empty())
         {
             // Handle arrays for multiple same-tag children / attributes
-            std::unordered_map<std::string, DataTree> obj;
+            std::map<std::string, DataTree> obj;
             std::unordered_map<std::string, std::vector<DataTree>> child_groups;
 
             for (const auto& [child_tag, child_value] : children)
@@ -480,19 +480,10 @@ struct XmlDataSerializer
         {
             const auto& obj = value.as<DataTree::Object>();
 
-            // Sort keys for consistent output
-            std::vector<DataTree::Object::key_type> keys;
-            std::transform(obj.begin(), obj.end(), std::back_inserter(keys),
-                           [](const auto& pair) { return pair.first; });
-            std::sort(keys.begin(), keys.end());
-
             // Opening tag with attributes
             output_ << indent_str << opening_tag;
-            for (size_t i = 0; i < keys.size(); ++i)
+            for (const auto & [key, val] : obj)
             {
-                const auto& key = keys[i];
-                const auto& val = obj.at(key);
-
                 if (key.rfind("@", 0) == 0)
                 {
                     // Attribute
@@ -512,11 +503,8 @@ struct XmlDataSerializer
             output_ << newline;
 
             // Child elements and text content
-            for (size_t i = 0; i < keys.size(); ++i)
+            for (const auto & [key, val] : obj)
             {
-                const auto& key = keys[i];
-                const auto& val = obj.at(key);
-
                 // Skip already handled attributes and text content handled later
                 if (key.rfind("@", 0) == 0 || key == "#text")
                     continue;

src/data_processors/yaml_processor.cc

@@ -553,17 +553,8 @@ struct YamlDataSerializer
 
     void serialize_mapping(const DataTree::Object& obj, size_t indent, size_t current_indent)
     {
-        // Sort keys for consistent output
-        std::vector<DataTree::Object::key_type> keys;
-        std::transform(obj.begin(), obj.end(), std::back_inserter(keys),
-                        [](const auto& pair) { return pair.first; });
-        std::sort(keys.begin(), keys.end());
-
-        for (size_t i = 0; i < keys.size(); ++i)
+        for (const auto & [key, val] : obj)
         {
-            const auto& key = keys[i];
-            const auto& val = obj.at(key);
-
             output_ << std::string(current_indent, ' ') << key << ":";
 
             if (val.is_object() || val.is_array())