Respect YAML::Null node by parsing

Co-authored-by: Evgueni Driouk <[email protected]>

Author: spcaipers-arm

libs/ymltree/src/YmlFormatter.cpp

@@ -25,8 +25,12 @@ static void EmitElement(YAML::Emitter& emitter, XMLTreeElement* element)
   auto& attributes = element->GetAttributes();
   const string& text = element->GetText();
   auto& children = element->GetChildren();
-  if (!text.empty() && attributes.empty() && children.empty()) {
-    emitter << text;
+  if (attributes.empty() && children.empty()) {
+    if(!text.empty()) {
+      emitter << text;
+    } else {
+      emitter << YAML::Null;
+    }
     return;
   }
 
@@ -40,9 +44,14 @@ static void EmitElement(YAML::Emitter& emitter, XMLTreeElement* element)
   }
    // treat everything else as a map
   emitter << YAML::BeginMap;
-  if (!attributes.empty()) {
-    for (auto [k, v] : attributes) {
-      emitter << YAML::Key << k << YAML::Value << v;
+  if(!attributes.empty()) {
+    for(auto [k, v] : attributes) {
+      emitter << YAML::Key << k;
+      if(!v.empty()) {
+        emitter << YAML::Value << v;
+      } else {
+        emitter << YAML::Null;
+      }
     }
   }
 
@@ -70,6 +79,7 @@ std::string YmlFormatter::FormatElement(XMLTreeElement* rootElement,
     return RteUtils::EMPTY_STRING;
   }
   YAML::Emitter emitter;
+  emitter.SetNullFormat(YAML::EmptyNull);
   emitter << YAML::BeginMap;
   if (rootElement->GetChildCount() > 1 && rootElement->GetTag().empty()) {
     for (auto child : rootElement->GetChildren()) {

libs/ymltree/src/YmlTreeParserInterface.cpp

@@ -92,8 +92,9 @@ bool YmlTreeParserInterface::ParseMapNode(const YAML::Node& node)
     auto& key = it.first;
     auto& val = it.second;
     const string tag = key.as<string>();
-    if (val.IsScalar() && builder->HasRoot()) {
-      builder->AddAttribute(tag, val.as<string>());
+    if ((val.IsScalar() || val.IsNull()) && builder->HasRoot()) {
+      const string value = val.IsScalar() ? val.as<string>() : "";
+      builder->AddAttribute(tag, value);
     } else {
       if(!ParseNode(val, tag)) {
         return false;
@@ -134,7 +135,6 @@ bool YmlTreeParserInterface::DoParseNode(const YAML::Node& node, const string& t
     return ParseMapNode(node);
 
   case NodeType::Null:
-    return false;
   case NodeType::Undefined:
   default:
     break;

libs/ymltree/test/YmlTreeTest.cpp

@@ -130,20 +130,42 @@ TEST(YmlTreeTest, KeyVal) {
   EXPECT_TRUE(tree.GetRoot());
   root = tree.GetRoot() ? tree.GetRoot()->GetFirstChild() : nullptr;
   EXPECT_TRUE(root);
+  EXPECT_EQ(root->GetTag(), "key1");
+  EXPECT_EQ(root->GetText(), "val1");
 
   xmlContent = xmlFormatter.FormatElement(root);
   EXPECT_EQ(xmlContent, expected_output1);
+  string ymlContent1 = ymlFormatter.FormatElement(root);
+  EXPECT_EQ(ymlContent1, yaml_input1);
+
+  const string yaml_input2 = "key2: "; // null node type  (trailing space is intentional because added by emitter)
+  const string expected_output2 = XML_HEADER + "<key2/>\n";
+
+   tree.Clear();
+  EXPECT_TRUE(tree.ParseString(yaml_input2));
+  EXPECT_TRUE(tree.GetRoot());
+  root = tree.GetRoot() ? tree.GetRoot()->GetFirstChild() : nullptr;
+  EXPECT_TRUE(root);
+  EXPECT_EQ(root->GetTag(), "key2");
+  EXPECT_EQ(root->GetText(), "");
+
+  xmlContent = xmlFormatter.FormatElement(root);
+  EXPECT_EQ(xmlContent, expected_output2);
+  string ymlContent2 = ymlFormatter.FormatElement(root);
+  EXPECT_EQ(ymlContent2, yaml_input2);
+
 }
 
 TEST(YmlTreeTest, Map) {
   const string yaml_input =
  "map:\n\
+  nul: \n\
   one: 1\n\
   two: 2";
 
-  const string json_input = "map: {one: 1, two: 2}\n";
+  const string json_input = "map: {nul:, one: 1, two: 2}\n";
 
-  const string expected_output = XML_HEADER + "<map one=\"1\" two=\"2\"/>\n";
+  const string expected_output = XML_HEADER + "<map nul=\"\" one=\"1\" two=\"2\"/>\n";
 
   YmlTree tree;
   EXPECT_TRUE(tree.ParseString(yaml_input));
@@ -175,6 +197,7 @@ TEST(YmlTreeTest, Nested) {
   one: 1\n\
   two: 2\n\
   three:\n\
+    s_null: \n\
     s_one: 3.1\n\
     s_two: 3.2\n\
   four:\n\
@@ -183,7 +206,7 @@ TEST(YmlTreeTest, Nested) {
       4.2.b: b";
   const string expected_output = XML_HEADER +
     "<nested one=\"1\" two=\"2\">\n\
-  <three s_one=\"3.1\" s_two=\"3.2\"/>\n\
+  <three s_null=\"\" s_one=\"3.1\" s_two=\"3.2\"/>\n\
   <four>\n\
     <->4.1</->\n\
     <- 4.2.a=\"a\" 4.2.b=\"b\"/>\n\