From 1a249f9d852408fba6978725170ba272844c5642 Mon Sep 17 00:00:00 2001
From: Tim Ledbetter <timledbetter@gmail.com>
Date: Sun, 18 Feb 2024 14:27:25 +0000
Subject: [PATCH] LibWeb: Add ad-hoc method for serializing CDATASection nodes
 to string

Previously, CDATASection nodes were being serialized as if they were
text, which meant they were missing their start and end delimiters.
Occurrences of the '&', '<' and '>' characters were also being replaced
with their entity names.
---
 .../LibWeb/DOMParsing/XMLSerializer.cpp       | 23 ++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp b/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp
index c2d20365191..ea076a78487 100644
--- a/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp
+++ b/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp
@@ -161,6 +161,7 @@ static WebIDL::ExceptionOr<String> serialize_text(DOM::Text const& text, Require
 static WebIDL::ExceptionOr<String> serialize_document_fragment(DOM::DocumentFragment const& document_fragment, Optional<FlyString>& namespace_, HashMap<FlyString, Vector<Optional<FlyString>>>& namespace_prefix_map, u64& prefix_index, RequireWellFormed require_well_formed);
 static WebIDL::ExceptionOr<String> serialize_document_type(DOM::DocumentType const& document_type, RequireWellFormed require_well_formed);
 static WebIDL::ExceptionOr<String> serialize_processing_instruction(DOM::ProcessingInstruction const& processing_instruction, RequireWellFormed require_well_formed);
+static WebIDL::ExceptionOr<String> serialize_cdata_section(DOM::CDATASection const& cdata_section, RequireWellFormed require_well_formed);
 
 // https://w3c.github.io/DOM-Parsing/#dfn-xml-serialization-algorithm
 WebIDL::ExceptionOr<String> serialize_node_to_xml_string_impl(JS::NonnullGCPtr<DOM::Node const> root, Optional<FlyString>& namespace_, HashMap<FlyString, Vector<Optional<FlyString>>>& namespace_prefix_map, u64& prefix_index, RequireWellFormed require_well_formed)
@@ -194,7 +195,7 @@ WebIDL::ExceptionOr<String> serialize_node_to_xml_string_impl(JS::NonnullGCPtr<D
         return serialize_comment(static_cast<DOM::Comment const&>(*root), require_well_formed);
     }
 
-    if (is<DOM::Text>(*root) || is<DOM::CDATASection>(*root)) {
+    if (is<DOM::Text>(*root)) {
         // -> Text
         //    Run the algorithm for XML serializing a Text node node.
         return serialize_text(static_cast<DOM::Text const&>(*root), require_well_formed);
@@ -218,6 +219,12 @@ WebIDL::ExceptionOr<String> serialize_node_to_xml_string_impl(JS::NonnullGCPtr<D
         return serialize_processing_instruction(static_cast<DOM::ProcessingInstruction const&>(*root), require_well_formed);
     }
 
+    if (is<DOM::CDATASection>(*root)) {
+        // Note: Serialization of CDATASection nodes is not mentioned in the specification, but treating CDATASection nodes as
+        // text leads to incorrect serialization.
+        return serialize_cdata_section(static_cast<DOM::CDATASection const&>(*root), require_well_formed);
+    }
+
     if (is<DOM::Attr>(*root)) {
         // -> An Attr object
         //    Return an empty string.
@@ -898,4 +905,18 @@ static WebIDL::ExceptionOr<String> serialize_processing_instruction(DOM::Process
     return MUST(markup.to_string());
 }
 
+// FIXME: This is ad-hoc
+static WebIDL::ExceptionOr<String> serialize_cdata_section(DOM::CDATASection const& cdata_section, RequireWellFormed require_well_formed)
+{
+    if (require_well_formed == RequireWellFormed::Yes && cdata_section.data().contains("]]>"sv))
+        return WebIDL::InvalidStateError::create(cdata_section.realm(), "CDATA section data contains a CDATA section end delimiter"_fly_string);
+
+    StringBuilder markup;
+    markup.append("<![CDATA["sv);
+    markup.append(cdata_section.data());
+    markup.append("]]>"sv);
+
+    return MUST(markup.to_string());
+}
+
 }