Auto merge of #22891 - georgeroman:implement_cdatasection, r=Manishearth

Implement CDATASection interface and createCDATASection method

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #22846

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/22891)
<!-- Reviewable:end -->

10 files changed, 96 insertions, 18 deletions

diff --git a/components/script/dom/cdatasection.rs b/components/script/dom/cdatasection.rs
new file mode 100644
index 00000000000..f4c788fd722
--- /dev/null
+++ b/components/script/dom/cdatasection.rs
@@ -0,0 +1,32 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::codegen::Bindings::CDATASectionBinding;
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::bindings::str::DOMString;
+use crate::dom::document::Document;
+use crate::dom::node::Node;
+use crate::dom::text::Text;
+use dom_struct::dom_struct;
+
+#[dom_struct]
+pub struct CDATASection {
+    text: Text,
+}
+
+impl CDATASection {
+    fn new_inherited(text: DOMString, document: &Document) -> CDATASection {
+        CDATASection {
+            text: Text::new_inherited(text, document),
+        }
+    }
+
+    pub fn new(text: DOMString, document: &Document) -> DomRoot<CDATASection> {
+        Node::reflect_node(
+            Box::new(CDATASection::new_inherited(text, document)),
+            document,
+            CDATASectionBinding::Wrap,
+        )
+    }
+}
diff --git a/components/script/dom/characterdata.rs b/components/script/dom/characterdata.rs
index 24d042a3c12..54f3ab0e360 100644
--- a/components/script/dom/characterdata.rs
+++ b/components/script/dom/characterdata.rs
@@ -8,12 +8,13 @@ use crate::dom::bindings::cell::DomRefCell;
 use crate::dom::bindings::codegen::Bindings::CharacterDataBinding::CharacterDataMethods;
 use crate::dom::bindings::codegen::Bindings::NodeBinding::NodeBinding::NodeMethods;
 use crate::dom::bindings::codegen::Bindings::ProcessingInstructionBinding::ProcessingInstructionMethods;
-use crate::dom::bindings::codegen::InheritTypes::{CharacterDataTypeId, NodeTypeId};
+use crate::dom::bindings::codegen::InheritTypes::{CharacterDataTypeId, NodeTypeId, TextTypeId};
 use crate::dom::bindings::codegen::UnionTypes::NodeOrString;
 use crate::dom::bindings::error::{Error, ErrorResult, Fallible};
 use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::root::{DomRoot, LayoutDom};
 use crate::dom::bindings::str::DOMString;
+use crate::dom::cdatasection::CDATASection;
 use crate::dom::comment::Comment;
 use crate::dom::document::Document;
 use crate::dom::element::Element;
@@ -50,7 +51,10 @@ impl CharacterData {
                 let pi = self.downcast::<ProcessingInstruction>().unwrap();
                 DomRoot::upcast(ProcessingInstruction::new(pi.Target(), data, &document))
             },
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => {
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::CDATASection)) => {
+                DomRoot::upcast(CDATASection::new(data, &document))
+            },
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::Text)) => {
                 DomRoot::upcast(Text::new(data, &document))
             },
             _ => unreachable!(),
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 91ccc829719..b589d4e5b79 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -35,6 +35,7 @@ use crate::dom::bindings::xmlname::XMLName::InvalidXMLName;
 use crate::dom::bindings::xmlname::{
     namespace_from_domstring, validate_and_extract, xml_name_type,
 };
+use crate::dom::cdatasection::CDATASection;
 use crate::dom::closeevent::CloseEvent;
 use crate::dom::comment::Comment;
 use crate::dom::compositionevent::CompositionEvent;
@@ -3610,6 +3611,22 @@ impl DocumentMethods for Document {
         Text::new(data, self)
     }
 
+    // https://dom.spec.whatwg.org/#dom-document-createcdatasection
+    fn CreateCDATASection(&self, data: DOMString) -> Fallible<DomRoot<CDATASection>> {
+        // Step 1
+        if self.is_html_document {
+            return Err(Error::NotSupported);
+        }
+
+        // Step 2
+        if data.contains("]]>") {
+            return Err(Error::InvalidCharacter);
+        }
+
+        // Step 3
+        Ok(CDATASection::new(data, self))
+    }
+
     // https://dom.spec.whatwg.org/#dom-document-createcomment
     fn CreateComment(&self, data: DOMString) -> DomRoot<Comment> {
         Comment::new(data, self)
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index b8f288a7e4e..e7ea25c565f 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -245,6 +245,7 @@ pub mod bluetoothuuid;
 pub mod canvasgradient;
 pub mod canvaspattern;
 pub mod canvasrenderingcontext2d;
+pub mod cdatasection;
 pub mod channelmergernode;
 pub mod channelsplitternode;
 pub mod characterdata;
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 7b5d4157bc0..3331686eef4 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -19,7 +19,7 @@ use crate::dom::bindings::conversions::{self, DerivedFrom};
 use crate::dom::bindings::error::{Error, ErrorResult, Fallible};
 use crate::dom::bindings::inheritance::{Castable, CharacterDataTypeId, ElementTypeId};
 use crate::dom::bindings::inheritance::{EventTargetTypeId, HTMLElementTypeId, NodeTypeId};
-use crate::dom::bindings::inheritance::{SVGElementTypeId, SVGGraphicsElementTypeId};
+use crate::dom::bindings::inheritance::{SVGElementTypeId, SVGGraphicsElementTypeId, TextTypeId};
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
 use crate::dom::bindings::root::{Dom, DomRoot, DomSlice, LayoutDom, MutNullableDom};
 use crate::dom::bindings::str::{DOMString, USVString};
@@ -559,7 +559,7 @@ impl Node {
         }
 
         match self.type_id() {
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => self
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::Text)) => self
                 .parent_node
                 .get()
                 .unwrap()
@@ -1577,7 +1577,7 @@ impl Node {
 
         // Step 4-5.
         match node.type_id() {
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => {
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) => {
                 if parent.is::<Document>() {
                     return Err(Error::HierarchyRequest);
                 }
@@ -2081,7 +2081,12 @@ impl NodeMethods for Node {
     // https://dom.spec.whatwg.org/#dom-node-nodetype
     fn NodeType(&self) -> u16 {
         match self.type_id() {
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => NodeConstants::TEXT_NODE,
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::Text)) => {
+                NodeConstants::TEXT_NODE
+            },
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::CDATASection)) => {
+                NodeConstants::CDATA_SECTION_NODE
+            },
             NodeTypeId::CharacterData(CharacterDataTypeId::ProcessingInstruction) => {
                 NodeConstants::PROCESSING_INSTRUCTION_NODE
             },
@@ -2097,7 +2102,12 @@ impl NodeMethods for Node {
     fn NodeName(&self) -> DOMString {
         match self.type_id() {
             NodeTypeId::Element(..) => self.downcast::<Element>().unwrap().TagName(),
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => DOMString::from("#text"),
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::Text)) => {
+                DOMString::from("#text")
+            },
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(TextTypeId::CDATASection)) => {
+                DOMString::from("#cdata-section")
+            },
             NodeTypeId::CharacterData(CharacterDataTypeId::ProcessingInstruction) => {
                 self.downcast::<ProcessingInstruction>().unwrap().Target()
             },
@@ -2253,7 +2263,7 @@ impl NodeMethods for Node {
 
         // Step 4-5.
         match node.type_id() {
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) if self.is::<Document>() => {
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) if self.is::<Document>() => {
                 return Err(Error::HierarchyRequest);
             },
             NodeTypeId::DocumentType if !self.is::<Document>() => {
@@ -2476,7 +2486,7 @@ impl NodeMethods for Node {
                 {
                     return false;
                 }
-                NodeTypeId::CharacterData(CharacterDataTypeId::Text) |
+                NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) |
                 NodeTypeId::CharacterData(CharacterDataTypeId::Comment)
                     if !is_equal_characterdata(this, node) =>
                 {
@@ -2931,7 +2941,7 @@ impl Into<LayoutNodeType> for NodeTypeId {
     fn into(self) -> LayoutNodeType {
         match self {
             NodeTypeId::Element(e) => LayoutNodeType::Element(e.into()),
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => LayoutNodeType::Text,
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) => LayoutNodeType::Text,
             x => unreachable!("Layout should not traverse nodes of type {:?}", x),
         }
     }
diff --git a/components/script/dom/range.rs b/components/script/dom/range.rs
index 5a81ba595b6..630c4acd245 100644
--- a/components/script/dom/range.rs
+++ b/components/script/dom/range.rs
@@ -707,14 +707,14 @@ impl RangeMethods for Range {
         }
         match start_node.type_id() {
             // Handled under step 2.
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => (),
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) => (),
             NodeTypeId::CharacterData(_) => return Err(Error::HierarchyRequest),
             _ => (),
         }
 
         // Step 2.
-        let (reference_node, parent) =
-            if start_node.type_id() == NodeTypeId::CharacterData(CharacterDataTypeId::Text) {
+        let (reference_node, parent) = match start_node.type_id() {
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) => {
                 // Step 3.
                 let parent = match start_node.GetParentNode() {
                     Some(parent) => parent,
@@ -723,11 +723,13 @@ impl RangeMethods for Range {
                 };
                 // Step 5.
                 (Some(DomRoot::from_ref(&*start_node)), parent)
-            } else {
+            },
+            _ => {
                 // Steps 4-5.
                 let child = start_node.ChildNodes().Item(start_offset);
                 (child, DomRoot::from_ref(&*start_node))
-            };
+            },
+        };
 
         // Step 6.
         Node::ensure_pre_insertion_validity(node, &parent, reference_node.deref())?;
@@ -955,7 +957,7 @@ impl RangeMethods for Range {
             NodeTypeId::Document(_) | NodeTypeId::DocumentFragment => None,
             NodeTypeId::Element(_) => Some(DomRoot::downcast::<Element>(node).unwrap()),
             NodeTypeId::CharacterData(CharacterDataTypeId::Comment) |
-            NodeTypeId::CharacterData(CharacterDataTypeId::Text) => node.GetParentElement(),
+            NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) => node.GetParentElement(),
             NodeTypeId::CharacterData(CharacterDataTypeId::ProcessingInstruction) |
             NodeTypeId::DocumentType => unreachable!(),
         };
diff --git a/components/script/dom/servoparser/html.rs b/components/script/dom/servoparser/html.rs
index 45ef625a5ee..fe6d06064f4 100644
--- a/components/script/dom/servoparser/html.rs
+++ b/components/script/dom/servoparser/html.rs
@@ -232,7 +232,7 @@ impl<'a> Serialize for &'a Node {
                         serializer.write_doctype(&doctype.name())?;
                     },
 
-                    NodeTypeId::CharacterData(CharacterDataTypeId::Text) => {
+                    NodeTypeId::CharacterData(CharacterDataTypeId::Text(_)) => {
                         let cdata = n.downcast::<CharacterData>().unwrap();
                         serializer.write_text(&cdata.data())?;
                     },
diff --git a/components/script/dom/text.rs b/components/script/dom/text.rs
index 49deffb071a..a3b66583d83 100644
--- a/components/script/dom/text.rs
+++ b/components/script/dom/text.rs
@@ -24,7 +24,7 @@ pub struct Text {
 }
 
 impl Text {
-    fn new_inherited(text: DOMString, document: &Document) -> Text {
+    pub fn new_inherited(text: DOMString, document: &Document) -> Text {
         Text {
             characterdata: CharacterData::new_inherited(text, document),
         }
diff --git a/components/script/dom/webidls/CDATASection.webidl b/components/script/dom/webidls/CDATASection.webidl
new file mode 100644
index 00000000000..cddd6edef6f
--- /dev/null
+++ b/components/script/dom/webidls/CDATASection.webidl
@@ -0,0 +1,10 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+/*
+ * The origin of this IDL file is
+ * https://dom.spec.whatwg.org/#interface-cdatasection
+ */
+
+interface CDATASection : Text {
+};
diff --git a/components/script/dom/webidls/Document.webidl b/components/script/dom/webidls/Document.webidl
index 91e82cfcd65..ccc3d339377 100644
--- a/components/script/dom/webidls/Document.webidl
+++ b/components/script/dom/webidls/Document.webidl
@@ -40,6 +40,8 @@ interface Document : Node {
   DocumentFragment createDocumentFragment();
   [NewObject]
   Text createTextNode(DOMString data);
+  [NewObject, Throws]
+  CDATASection createCDATASection(DOMString data);
   [NewObject]
   Comment createComment(DOMString data);
   [NewObject, Throws]