Auto merge of #5858 - pgonda:tabindex-focus-flag, r=jdm

Added support for the tabindex field, also added its correct defaults (-2 TODOs for things not supported in Servo yet).  Also added tabindex logic into Element::is_focusable_area.

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components/script/dom/element.rs

@@ -54,7 +54,7 @@ use dom::htmltablecellelement::{HTMLTableCellElement, HTMLTableCellElementHelper
 use dom::htmltablerowelement::{HTMLTableRowElement, HTMLTableRowElementHelpers};
 use dom::htmltablesectionelement::{HTMLTableSectionElement, HTMLTableSectionElementHelpers};
 use dom::htmltextareaelement::{HTMLTextAreaElement, RawLayoutHTMLTextAreaElementHelpers};
-use dom::node::{CLICK_IN_PROGRESS, LayoutNodeHelpers, Node, NodeHelpers, NodeTypeId};
+use dom::node::{CLICK_IN_PROGRESS, LayoutNodeHelpers, Node, NodeHelpers, NodeTypeId, SEQUENTIALLY_FOCUSABLE};
 use dom::node::{document_from_node, NodeDamage};
 use dom::node::{window_from_node};
 use dom::nodelist::NodeList;
@@ -757,9 +757,11 @@ impl<'a> FocusElementHelpers for JSRef<'a, Element> {
             return false;
         }
         // TODO: Check whether the element is being rendered (i.e. not hidden).
-        // TODO: Check the tabindex focus flag.
-        // https://html.spec.whatwg.org/multipage/#specially-focusable
         let node: JSRef<Node> = NodeCast::from_ref(self);
+        if node.get_flag(SEQUENTIALLY_FOCUSABLE) {
+            return true;
+        }
+        // https://html.spec.whatwg.org/multipage/#specially-focusable
         match node.type_id() {
             NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLAnchorElement)) |
             NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLInputElement)) |
@@ -979,6 +981,9 @@ impl<'a> AttributeHandlers for JSRef<'a, Element> {
 
             self.attrs.borrow_mut().remove(idx);
             attr.r().set_owner(None);
+            if attr.r().namespace() == &ns!("") {
+                vtable_for(&NodeCast::from_ref(self)).after_remove_attr(attr.r().name());
+            }
 
             let node: JSRef<Node> = NodeCast::from_ref(self);
             if node.is_in_doc() {

components/script/dom/htmlelement.rs

@@ -4,6 +4,7 @@
 
 use dom::attr::Attr;
 use dom::attr::AttrHelpers;
+use dom::attr::AttrValue;
 use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::Bindings::HTMLElementBinding;
 use dom::bindings::codegen::Bindings::HTMLElementBinding::HTMLElementMethods;
@@ -24,7 +25,7 @@ use dom::eventtarget::{EventTarget, EventTargetHelpers, EventTargetTypeId};
 use dom::htmlinputelement::HTMLInputElement;
 use dom::htmlmediaelement::HTMLMediaElementTypeId;
 use dom::htmltablecellelement::HTMLTableCellElementTypeId;
-use dom::node::{Node, NodeHelpers, NodeTypeId, document_from_node, window_from_node};
+use dom::node::{Node, NodeHelpers, NodeTypeId, document_from_node, window_from_node, SEQUENTIALLY_FOCUSABLE};
 use dom::virtualmethods::VirtualMethods;
 use dom::window::WindowHelpers;
 
@@ -70,6 +71,7 @@ impl HTMLElement {
 
 trait PrivateHTMLElementHelpers {
     fn is_body_or_frameset(self) -> bool;
+    fn update_sequentially_focusable_status(self);
 }
 
 impl<'a> PrivateHTMLElementHelpers for JSRef<'a, HTMLElement> {
@@ -77,6 +79,44 @@ impl<'a> PrivateHTMLElementHelpers for JSRef<'a, HTMLElement> {
         let eventtarget: JSRef<EventTarget> = EventTargetCast::from_ref(self);
         eventtarget.is_htmlbodyelement() || eventtarget.is_htmlframesetelement()
     }
+
+    fn update_sequentially_focusable_status(self) {
+        let element = ElementCast::from_ref(self);
+        let node = NodeCast::from_ref(self);
+        if element.has_attribute(&atom!("tabindex")) {
+            node.set_flag(SEQUENTIALLY_FOCUSABLE, true);
+        } else {
+            match node.type_id() {
+                NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLButtonElement)) |
+                NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLSelectElement)) |
+                NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLIFrameElement)) |
+                NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTextAreaElement))
+                    => node.set_flag(SEQUENTIALLY_FOCUSABLE, true),
+                NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLinkElement)) |
+                NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLAnchorElement)) => {
+                    if element.has_attribute(&atom!("href")) {
+                        node.set_flag(SEQUENTIALLY_FOCUSABLE, true);
+                    }
+                },
+                _ => {
+                    if let Some(attr) = element.get_attribute(&ns!(""), &atom!("draggable")) {
+                        let attr = attr.root();
+                        let attr = attr.r();
+                        let value = attr.value();
+                        let is_true = match *value {
+                            AttrValue::String(ref string) => string == "true",
+                            _ => false,
+                        };
+                        node.set_flag(SEQUENTIALLY_FOCUSABLE, is_true);
+                    } else {
+                        node.set_flag(SEQUENTIALLY_FOCUSABLE, false);
+                    }
+                    //TODO set SEQUENTIALLY_FOCUSABLE flag if editing host
+                    //TODO set SEQUENTIALLY_FOCUSABLE flag if "sorting interface th elements"
+                },
+            }
+        }
+    }
 }
 
 impl<'a> HTMLElementMethods for JSRef<'a, HTMLElement> {
@@ -220,6 +260,19 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLElement> {
         Some(element as &VirtualMethods)
     }
 
+    fn before_remove_attr(&self, attr: JSRef<Attr>) {
+        if let Some(ref s) = self.super_type() {
+            s.before_remove_attr(attr);
+        }
+    }
+
+    fn after_remove_attr(&self, name: &Atom) {
+        if let Some(ref s) = self.super_type() {
+            s.after_remove_attr(name);
+        }
+        self.update_sequentially_focusable_status();
+    }
+
     fn after_set_attr(&self, attr: JSRef<Attr>) {
         if let Some(ref s) = self.super_type() {
             s.after_set_attr(attr);
@@ -236,6 +289,13 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLElement> {
                                                   &name[2..],
                                                   (**attr.value()).to_owned());
         }
+        self.update_sequentially_focusable_status();
+    }
+    fn bind_to_tree(&self, tree_in_doc: bool) {
+        if let Some(ref s) = self.super_type() {
+            s.bind_to_tree(tree_in_doc);
+        }
+        self.update_sequentially_focusable_status();
     }
 }
 

components/script/dom/node.rs

@@ -158,6 +158,9 @@ bitflags! {
         const CLICK_IN_PROGRESS = 0x100,
         #[doc = "Specifies whether this node has the focus."]
         const IN_FOCUS_STATE = 0x200,
+        #[doc = "Specifies whether this node is focusable and whether it is supposed \
+                 to be reachable with using sequential focus navigation."]
+        const SEQUENTIALLY_FOCUSABLE = 0x400,
     }
 }
 

components/script/dom/virtualmethods.rs

@@ -91,6 +91,14 @@ pub trait VirtualMethods {
         }
     }
 
+    /// Called when changing or removing attributes, after all modification
+    /// has taken place.
+    fn after_remove_attr(&self, name: &Atom) {
+        if let Some(ref s) = self.super_type() {
+            s.after_remove_attr(name);
+        }
+    }
+
     /// Returns the right AttrValue variant for the attribute with name `name`
     /// on this element.
     fn parse_plain_attribute(&self, name: &Atom, value: DOMString) -> AttrValue {

tests/wpt/metadata/html/semantics/disabled-elements/disabledElement.html.ini

@@ -1,5 +0,0 @@
-[disabledElement.html]
-  type: testharness
-  [A disabled <span> should be focusable]
-    expected: FAIL
-

tests/wpt/metadata/html/semantics/selectors/pseudo-classes/focus.html.ini

@@ -3,12 +3,5 @@
   [input3 has the attribute autofocus]
     expected: FAIL
 
-  [tabindex attribute makes the element focusable]
-    expected: FAIL
-
   [editable elements are focusable]
     expected: FAIL
-
-  [':focus' matches focussed body with tabindex]
-    expected: FAIL
-