Auto merge of #259 - servo:form-owner, r=nox

Implement support for form owner

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Author: bors-servo

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "html5ever"
-version = "0.13.1"
+version = "0.14.0"
 authors = [ "The html5ever Project Developers" ]
 license = "MIT / Apache-2.0"
 repository = "https://github.com/servo/html5ever"

examples/noop-tree-builder.rs

@@ -57,6 +57,10 @@ impl TreeSink for Sink {
         x == y
     }
 
+    fn same_tree(&self, _x: usize, _y: usize) -> bool {
+        true
+    }
+
     fn elem_name(&self, target: usize) -> QualName {
         self.names.get(&target).expect("not an element").clone()
     }
@@ -71,13 +75,15 @@ impl TreeSink for Sink {
         self.get_id()
     }
 
+    fn has_parent_node(&self, _node: usize) -> bool {
+        // `node` will have a parent unless a script moved it, and we're
+        // not running scripts.  Therefore we can aways return true.
+        true
+    }
+
     fn append_before_sibling(&mut self,
             _sibling: usize,
-            _new_node: NodeOrText<usize>) -> Result<(), NodeOrText<usize>> {
-        // `sibling` will have a parent unless a script moved it, and we're
-        // not running scripts.  Therefore we can aways return `Ok(())`.
-        Ok(())
-    }
+            _new_node: NodeOrText<usize>) { }
 
     fn parse_error(&mut self, _msg: Cow<'static, str>) { }
     fn set_quirks_mode(&mut self, _mode: QuirksMode) { }

examples/print-tree-actions.rs

@@ -82,6 +82,12 @@ impl TreeSink for Sink {
         id
     }
 
+    fn has_parent_node(&self, _node: usize) -> bool  {
+        // `node` will have a parent unless a script moved it, and we're
+        // not running scripts.  Therefore we can aways return true
+        true
+    }
+
     fn append(&mut self, parent: usize, child: NodeOrText<usize>) {
         match child {
             AppendNode(n)
@@ -93,17 +99,13 @@ impl TreeSink for Sink {
 
     fn append_before_sibling(&mut self,
             sibling: usize,
-            new_node: NodeOrText<usize>) -> Result<(), NodeOrText<usize>> {
+            new_node: NodeOrText<usize>) {
         match new_node {
             AppendNode(n)
                 => println!("Append node {} before {}", n, sibling),
             AppendText(t)
                 => println!("Append text before {}: \"{}\"", sibling, escape_default(&t)),
         }
-
-        // `sibling` will have a parent unless a script moved it, and we're
-        // not running scripts.  Therefore we can aways return `Ok(())`.
-        Ok(())
     }
 
     fn append_doctype_to_document(&mut self,
@@ -121,6 +123,12 @@ impl TreeSink for Sink {
         }
     }
 
+    fn associate_with_form(&mut self, _target: usize, _form: usize) {
+        // No form owner support. Since same_tree always returns
+        // true we cannot be sure that this associate_with_form call is
+        // valid
+    }
+
     fn remove_from_parent(&mut self, target: usize) {
         println!("Remove {} from parent", target);
     }

src/rcdom.rs

@@ -223,6 +223,11 @@ impl TreeSink for RcDom {
         new_node(Comment(text))
     }
 
+    fn has_parent_node(&self, node: Handle) -> bool {
+        let node = node.borrow();
+        node.parent.is_some()
+    }
+
     fn append(&mut self, parent: Handle, child: NodeOrText<Handle>) {
         // Append to an existing Text node if we have one.
         match child {
@@ -241,8 +246,9 @@ impl TreeSink for RcDom {
 
     fn append_before_sibling(&mut self,
             sibling: Handle,
-            child: NodeOrText<Handle>) -> Result<(), NodeOrText<Handle>> {
-        let (parent, i) = unwrap_or_return!(get_parent_and_index(&sibling), Err(child));
+            child: NodeOrText<Handle>) {
+        let (parent, i) = get_parent_and_index(&sibling)
+            .expect("append_before_sibling called on node without parent");
 
         let child = match (child, i) {
             // No previous node.
@@ -253,7 +259,7 @@ impl TreeSink for RcDom {
                 let parent = parent.borrow();
                 let prev = &parent.children[i-1];
                 if append_to_existing_text(prev, &text) {
-                    return Ok(());
+                    return;
                 }
                 new_node(Text(text))
             }
@@ -271,7 +277,6 @@ impl TreeSink for RcDom {
 
         child.borrow_mut().parent = Some(Rc::downgrade(&parent));
         parent.borrow_mut().children.insert(i, child);
-        Ok(())
     }
 
     fn append_doctype_to_document(&mut self,

src/tree_builder/actions.rs

@@ -210,40 +210,8 @@ impl<Handle, Sink> TreeBuilderActions<Handle>
 
     // Insert at the "appropriate place for inserting a node".
     fn insert_appropriately(&mut self, child: NodeOrText<Handle>, override_target: Option<Handle>) {
-        declare_tag_set!(foster_target = "table" "tbody" "tfoot" "thead" "tr");
-        let target = override_target.unwrap_or_else(|| self.current_node());
-        if !(self.foster_parenting && self.elem_in(target.clone(), foster_target)) {
-            if self.html_elem_named(target.clone(), local_name!("template")) {
-                // No foster parenting (inside template).
-                let contents = self.sink.get_template_contents(target);
-                self.sink.append(contents, child);
-            } else {
-                // No foster parenting (the common case).
-                self.sink.append(target, child);
-            }
-            return;
-        }
-
-        // Foster parenting
-        let mut iter = self.open_elems.iter().rev().peekable();
-        while let Some(elem) = iter.next() {
-            if self.html_elem_named(elem.clone(), local_name!("template")) {
-                let contents = self.sink.get_template_contents(elem.clone());
-                self.sink.append(contents, child);
-                return;
-            } else if self.html_elem_named(elem.clone(), local_name!("table")) {
-                // Try inserting "inside last table's parent node, immediately before last table"
-                if let Err(child) = self.sink.append_before_sibling(elem.clone(), child) {
-                    // If last_table has no parent, we regain ownership of the child.
-                    // Insert "inside previous element, after its last child (if any)"
-                    let previous_element = (*iter.peek().unwrap()).clone();
-                    self.sink.append(previous_element, child);
-                }
-                return;
-            }
-        }
-        let html_elem = self.html_elem();
-        self.sink.append(html_elem, child);
+        let insertion_point = self.appropriate_place_for_insertion(override_target);
+        self.insert_at(insertion_point, child);
     }
 
     fn adoption_agency(&mut self, subject: LocalName) {
@@ -775,10 +743,40 @@ impl<Handle, Sink> TreeBuilderActions<Handle>
         // FIXME: application cache selection algorithm
     }
 
+    // https://html.spec.whatwg.org/multipage/#create-an-element-for-the-token
     fn insert_element(&mut self, push: PushFlag, ns: Namespace, name: LocalName, attrs: Vec<Attribute>)
             -> Handle {
-        let elem = self.sink.create_element(QualName::new(ns, name), attrs);
-        self.insert_appropriately(AppendNode(elem.clone()), None);
+        declare_tag_set!(form_associatable =
+            "button" "fieldset" "input" "object"
+            "output" "select" "textarea" "img");
+
+        declare_tag_set!(listed = [form_associatable] - "img");
+
+        // Step 7.
+        let qname = QualName::new(ns, name);
+        let elem = self.sink.create_element(qname.clone(), attrs.clone());
+
+        let insertion_point = self.appropriate_place_for_insertion(None);
+        let tree_node = match insertion_point {
+            LastChild(ref p) |
+            BeforeSibling(ref p) => p.clone()
+        };
+
+        // Step 12.
+        if form_associatable(qname.clone()) &&
+           self.form_elem.is_some() &&
+           !self.in_html_elem_named(local_name!("template")) &&
+           !(listed(qname.clone()) &&
+                attrs.iter().any(|a| a.name == qualname!("","form"))) {
+
+               let form = self.form_elem.as_ref().unwrap().clone();
+               if self.sink.same_tree(tree_node, form.clone()) {
+                   self.sink.associate_with_form(elem.clone(), form)
+               }
+        }
+
+        self.insert_at(insertion_point, AppendNode(elem.clone()));
+
         match push {
             Push => self.push(&elem),
             NoPush => (),

src/tree_builder/interface.rs

@@ -72,6 +72,11 @@ pub trait TreeSink {
     /// Do two handles refer to the same node?
     fn same_node(&self, x: Self::Handle, y: Self::Handle) -> bool;
 
+    /// Are two handles present in the same tree
+    fn same_tree(&self, x: Self::Handle, y: Self::Handle) -> bool {
+        true
+    }
+
     /// What is the name of this element?
     ///
     /// Should never be called on a non-element node;
@@ -93,15 +98,18 @@ pub trait TreeSink {
     /// Create a comment node.
     fn create_comment(&mut self, text: StrTendril) -> Self::Handle;
 
+    /// Does the node have a parent?
+    fn has_parent_node(&self, node: Self::Handle) -> bool;
+
     /// Append a node as the last child of the given node.  If this would
     /// produce adjacent sibling text nodes, it should concatenate the text
     /// instead.
     ///
     /// The child node will not already have a parent.
     fn append(&mut self, parent: Self::Handle, child: NodeOrText<Self::Handle>);
 
-    /// Append a node as the sibling immediately before the given node.  If that node
-    /// has no parent, do nothing and return Err(new_node).
+    /// Append a node as the sibling immediately before the given node.
+    /// This method will only be called if has_parent_node(sibling) is true
     ///
     /// The tree builder promises that `sibling` is not a text node.  However its
     /// old previous sibling, which would become the new node's previous sibling,
@@ -111,7 +119,7 @@ pub trait TreeSink {
     /// NB: `new_node` may have an old parent, from which it should be removed.
     fn append_before_sibling(&mut self,
         sibling: Self::Handle,
-        new_node: NodeOrText<Self::Handle>) -> Result<(), NodeOrText<Self::Handle>>;
+        new_node: NodeOrText<Self::Handle>);
 
     /// Append a `DOCTYPE` element to the `Document` node.
     fn append_doctype_to_document(&mut self,
@@ -124,6 +132,9 @@ pub trait TreeSink {
     /// with something else than an element.
     fn add_attrs_if_missing(&mut self, target: Self::Handle, attrs: Vec<Attribute>);
 
+    /// Associate the given form-associatable element with the form element
+    fn associate_with_form(&mut self, target: Self::Handle, form: Self::Handle) {}
+
     /// Detach the given node from its parent.
     fn remove_from_parent(&mut self, target: Self::Handle);
 

src/tree_builder/mod.rs

@@ -369,6 +369,54 @@ impl<Handle, Sink> TreeBuilder<Handle, Sink>
     pub fn is_fragment(&self) -> bool {
         self.context_elem.is_some()
     }
+
+    /// https://html.spec.whatwg.org/multipage/#appropriate-place-for-inserting-a-node
+    fn appropriate_place_for_insertion(&mut self,
+                                       override_target: Option<Handle>)
+                                       -> InsertionPoint<Handle> {
+        use self::tag_sets::*;
+
+        declare_tag_set!(foster_target = "table" "tbody" "tfoot" "thead" "tr");
+        let target = override_target.unwrap_or_else(|| self.current_node());
+        if !(self.foster_parenting && self.elem_in(target.clone(), foster_target)) {
+            if self.html_elem_named(target.clone(), local_name!("template")) {
+                // No foster parenting (inside template).
+                let contents = self.sink.get_template_contents(target);
+                return LastChild(contents);
+            } else {
+                // No foster parenting (the common case).
+                return LastChild(target);
+            }
+        }
+
+        // Foster parenting
+        let mut iter = self.open_elems.iter().rev().peekable();
+        while let Some(elem) = iter.next() {
+            if self.html_elem_named(elem.clone(), local_name!("template")) {
+                let contents = self.sink.get_template_contents(elem.clone());
+                return LastChild(contents);
+            } else if self.html_elem_named(elem.clone(), local_name!("table")) {
+                // Try inserting "inside last table's parent node, immediately before last table"
+                if self.sink.has_parent_node(elem.clone()) {
+                    return BeforeSibling(elem.clone());
+                } else {
+                    // If elem has no parent, we regain ownership of the child.
+                    // Insert "inside previous element, after its last child (if any)"
+                    let previous_element = (*iter.peek().unwrap()).clone();
+                    return LastChild(previous_element);
+                }
+            }
+        }
+        let html_elem = self.html_elem();
+        LastChild(html_elem)
+    }
+
+    fn insert_at(&mut self, insertion_point: InsertionPoint<Handle>, child: NodeOrText<Handle>) {
+        match insertion_point {
+            LastChild(parent) => self.sink.append(parent, child),
+            BeforeSibling(sibling) => self.sink.append_before_sibling(sibling, child)
+        }
+    }
 }
 
 impl<Handle, Sink> TokenSink
@@ -529,13 +577,18 @@ mod test {
             self.rcdom.create_comment(text)
         }
 
+        fn has_parent_node(&self, node: Handle) -> bool {
+            let node = node.borrow();
+            node.parent.is_some()
+        }
+
         fn append(&mut self, parent: Handle, child: NodeOrText<Handle>) {
             self.rcdom.append(parent, child)
         }
 
         fn append_before_sibling(&mut self,
                 sibling: Handle,
-                child: NodeOrText<Handle>) -> Result<(), NodeOrText<Handle>> {
+                child: NodeOrText<Handle>) {
             self.rcdom.append_before_sibling(sibling, child)
         }
 

src/tree_builder/types.rs

@@ -19,6 +19,7 @@ pub use self::SplitStatus::*;
 pub use self::Token::*;
 pub use self::ProcessResult::*;
 pub use self::FormatEntry::*;
+pub use self::InsertionPoint::*;
 
 #[derive(PartialEq, Eq, Copy, Clone, Debug)]
 pub enum InsertionMode {
@@ -80,3 +81,10 @@ pub enum FormatEntry<Handle> {
     Element(Handle, Tag),
     Marker,
 }
+
+pub enum InsertionPoint<Handle> {
+    /// Insert as last child in this parent.
+    LastChild(Handle),
+    /// Insert before this following sibling.
+    BeforeSibling(Handle)
+}