Auto merge of #8935 - Ms2ger:get_or_create, r=Manishearth

Avoid some rooting in parsing.

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components/script/dom/servohtmlparser.rs

@@ -16,13 +16,12 @@ use dom::bindings::trace::JSTraceable;
 use dom::document::Document;
 use dom::node::Node;
 use dom::servoxmlparser::ServoXMLParser;
-use dom::text::Text;
 use dom::window::Window;
 use encoding::all::UTF_8;
 use encoding::types::{DecoderTrap, Encoding};
 use html5ever::tokenizer;
 use html5ever::tree_builder;
-use html5ever::tree_builder::{NodeOrText, TreeBuilder, TreeBuilderOpts};
+use html5ever::tree_builder::{TreeBuilder, TreeBuilderOpts};
 use hyper::header::ContentType;
 use hyper::mime::{Mime, SubLevel, TopLevel};
 use js::jsapi::JSTracer;
@@ -36,7 +35,6 @@ use std::cell::UnsafeCell;
 use std::default::Default;
 use std::ptr;
 use url::Url;
-use util::str::DOMString;
 
 #[must_root]
 #[derive(JSTraceable, HeapSizeOf)]
@@ -45,21 +43,6 @@ pub struct Sink {
     pub document: JS<Document>,
 }
 
-impl Sink {
-    #[allow(unrooted_must_root)] // method is only run at parse time
-    pub fn get_or_create(&self, child: NodeOrText<JS<Node>>) -> Root<Node> {
-        match child {
-            NodeOrText::AppendNode(n) => Root::from_ref(&*n),
-            NodeOrText::AppendText(t) => {
-                // FIXME(ajeffrey): convert directly from tendrils to DOMStrings
-                let s: String = t.into();
-                let text = Text::new(DOMString::from(s), &self.document);
-                Root::upcast(text)
-            }
-        }
-    }
-}
-
 /// FragmentContext is used only to pass this group of related values
 /// into functions.
 #[derive(Copy, Clone)]

components/script/dom/servoxmlparser.rs

@@ -11,7 +11,6 @@ use dom::bindings::trace::JSTraceable;
 use dom::document::Document;
 use dom::node::Node;
 use dom::servohtmlparser::ParserRef;
-use dom::text::Text;
 use dom::window::Window;
 use js::jsapi::JSTracer;
 use msg::constellation_msg::PipelineId;
@@ -19,9 +18,8 @@ use parse::Parser;
 use script_task::ScriptTask;
 use std::cell::Cell;
 use url::Url;
-use util::str::DOMString;
 use xml5ever::tokenizer;
-use xml5ever::tree_builder::{self, NodeOrText, XmlTreeBuilder};
+use xml5ever::tree_builder::{self, XmlTreeBuilder};
 
 pub type Tokenizer = tokenizer::XmlTokenizer<XmlTreeBuilder<JS<Node>, Sink>>;
 
@@ -32,19 +30,6 @@ pub struct Sink {
     pub document: JS<Document>,
 }
 
-impl Sink {
-    #[allow(unrooted_must_root)] // method is only run at parse time
-    pub fn get_or_create(&self, child: NodeOrText<JS<Node>>) -> Root<Node> {
-        match child {
-            NodeOrText::AppendNode(n) => Root::from_ref(&*n),
-            NodeOrText::AppendText(t) => {
-                let s: String = t.into();
-                let text = Text::new(DOMString::from(s), &self.document);
-                Root::upcast(text)
-            }
-        }
-    }
-}
 #[must_root]
 #[dom_struct]
 pub struct ServoXMLParser {

components/script/parse/html.rs

@@ -24,6 +24,7 @@ use dom::node::{document_from_node, window_from_node};
 use dom::processinginstruction::ProcessingInstruction;
 use dom::servohtmlparser;
 use dom::servohtmlparser::{FragmentContext, ServoHTMLParser};
+use dom::text::Text;
 use encoding::types::Encoding;
 use html5ever::Attribute;
 use html5ever::serialize::TraversalScope;
@@ -39,6 +40,20 @@ use tendril::StrTendril;
 use url::Url;
 use util::str::DOMString;
 
+fn insert(parent: &Node, reference_child: Option<&Node>, child: NodeOrText<JS<Node>>) {
+    match child {
+        NodeOrText::AppendNode(n) => {
+            assert!(parent.InsertBefore(&n, reference_child).is_ok());
+        },
+        NodeOrText::AppendText(t) => {
+            // FIXME(ajeffrey): convert directly from tendrils to DOMStrings
+            let s: String = t.into();
+            let text = Text::new(DOMString::from(s), &parent.owner_doc());
+            assert!(parent.InsertBefore(text.upcast(), reference_child).is_ok());
+        }
+    }
+}
+
 impl<'a> TreeSink for servohtmlparser::Sink {
     type Handle = JS<Node>;
 
@@ -91,8 +106,7 @@ impl<'a> TreeSink for servohtmlparser::Sink {
             None => return Err(new_node),
         };
 
-        let child = self.get_or_create(new_node);
-        assert!(parent.InsertBefore(child.r(), Some(&*sibling)).is_ok());
+        insert(&parent, Some(&*sibling), new_node);
         Ok(())
     }
 
@@ -105,10 +119,8 @@ impl<'a> TreeSink for servohtmlparser::Sink {
     }
 
     fn append(&mut self, parent: JS<Node>, child: NodeOrText<JS<Node>>) {
-        let child = self.get_or_create(child);
-
         // FIXME(#3701): Use a simpler algorithm and merge adjacent text nodes
-        assert!(parent.AppendChild(child.r()).is_ok());
+        insert(&parent, None, child);
     }
 
     fn append_doctype_to_document(&mut self, name: StrTendril, public_id: StrTendril,