Bugfix: Handle data nodes when mutating element value

rapidxml.hpp

@@ -799,6 +799,8 @@ namespace rapidxml
         }
         void value(view_type const & v) {
             m_value = v;
+            this->value_raw("");
+            if (this->m_parent) this->m_parent->dirty_parent();
         }
         // Return true if the value has been decoded.
         bool value_decoded() const {
@@ -945,7 +947,18 @@ namespace rapidxml
         }
 
         void value(view_type const & v) {
+            if (this->m_type == node_element) {
+                // Set the first data node to the value, if one exists.
+                for (auto node = m_first_node; node; node = node->m_next_sibling) {
+                    if (node->type() == node_data) {
+                        node->value(v);
+                        break;
+                    }
+                }
+            }
             m_value = v;
+            this->value_raw("");
+            dirty();
         }
 
         bool value_decoded() const {

test/round-trips.cpp

@@ -121,6 +121,23 @@ TEST(RoundTrip, SimpleLtBody) {
     EXPECT_EQ(input, std::string(buffer.data(), buffer.size() - 1));
 }
 
+TEST(RoundTrip, MutateBody) {
+    const char input[] = "<simple arg=\"&apos;\">&lt;</simple>";
+    const char expected[] = "<simple arg=\"'\">&lt;</simple>";
+    const char expected2[] = "<simple arg=\"'\">new value</simple>";
+    std::vector<char> buffer{input, input + sizeof(input)};
+    rapidxml::xml_document<> doc;
+    doc.parse<rapidxml::parse_full>(buffer.data());
+    auto output = print(doc);
+    EXPECT_EQ(expected, output);
+    // Have we mutated the underlying buffer?
+    EXPECT_EQ(input, std::string(buffer.data(), buffer.size() - 1));
+    doc.first_node()->value("new value");
+    EXPECT_EQ(doc.first_node()->value_raw(), "");
+    EXPECT_EQ(doc.first_node()->value(), "new value");
+    EXPECT_EQ(expected2, print(doc));
+}
+
 TEST(RoundTrip, Everything) {
     const char input[] = "<?xml charset='utf-8' ?><!DOCTYPE ><simple arg=\"&apos;\"><!-- Comment here --></simple>";
     const char expected[] = "<?xml charset=\"utf-8\"?><!DOCTYPE ><simple arg=\"'\"><!-- Comment here --></simple>";