servo: Merge #5461 - Implement the :focus pseudo-class selector and element.focus/blur (from mbrubeck:focus); r=jdm

Fixes #5460. This supports for simple focusable elements that are their own DOM anchors, like text `input` fields.

Requires servo/rust-selectors#20.  r? @SimonSapin

Source-Repo: https://github.com/servo/servo
Source-Revision: b63fb0c0a7e9cd9208d66319c910750aaaac844c

servo/components/layout/wrapper.rs

@@ -581,6 +581,14 @@ impl<'le> TElement<'le> for LayoutElement<'le> {
         }
     }
 
+    #[inline]
+    fn get_focus_state(self) -> bool {
+        unsafe {
+            let node: &Node = NodeCast::from_actual(self.element);
+            node.get_focus_state_for_layout()
+        }
+    }
+
     #[inline]
     fn get_id(self) -> Option<Atom> {
         unsafe {

servo/components/script/dom/document.rs

@@ -454,7 +454,20 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
     /// transaction, or none if no elements requested it.
     fn commit_focus_transaction(self) {
         //TODO: dispatch blur, focus, focusout, and focusin events
+
+        if let Some(ref elem) = self.focused.get().root() {
+            let node: JSRef<Node> = NodeCast::from_ref(elem.r());
+            node.set_focus_state(false);
+        }
+
         self.focused.assign(self.possibly_focused.get());
+
+        if let Some(ref elem) = self.focused.get().root() {
+            let node: JSRef<Node> = NodeCast::from_ref(elem.r());
+            node.set_focus_state(true);
+        }
+        // TODO: Update the focus state for all elements in the focus chain.
+        // https://html.spec.whatwg.org/multipage/interaction.html#focus-chain
     }
 
     /// Handles any updates when the document's title has changed.

servo/components/script/dom/element.rs

@@ -1461,6 +1461,13 @@ impl<'a> style::node::TElement<'a> for JSRef<'a, Element> {
         let node: JSRef<Node> = NodeCast::from_ref(self);
         node.get_hover_state()
     }
+    fn get_focus_state(self) -> bool {
+        // TODO: Also check whether the top-level browsing context has the system focus,
+        // and whether this element is a browsing context container.
+        // https://html.spec.whatwg.org/multipage/scripting.html#selector-focus
+        let node: JSRef<Node> = NodeCast::from_ref(self);
+        node.get_focus_state()
+    }
     fn get_id(self) -> Option<Atom> {
         self.get_attribute(ns!(""), &atom!("id")).map(|attr| {
             let attr = attr.root();

servo/components/script/dom/htmlelement.rs

@@ -10,21 +10,21 @@ use dom::bindings::codegen::Bindings::HTMLElementBinding::HTMLElementMethods;
 use dom::bindings::codegen::Bindings::HTMLInputElementBinding::HTMLInputElementMethods;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::InheritTypes::{ElementCast, HTMLFrameSetElementDerived};
-use dom::bindings::codegen::InheritTypes::{EventTargetCast, HTMLInputElementCast};
+use dom::bindings::codegen::InheritTypes::{EventTargetCast, HTMLInputElementCast, NodeCast};
 use dom::bindings::codegen::InheritTypes::{HTMLElementDerived, HTMLBodyElementDerived};
 use dom::bindings::js::{JSRef, Temporary, MutNullableJS};
 use dom::bindings::error::ErrorResult;
 use dom::bindings::error::Error::Syntax;
 use dom::bindings::utils::Reflectable;
 use dom::cssstyledeclaration::{CSSStyleDeclaration, CSSModificationAccess};
-use dom::document::Document;
+use dom::document::{Document, DocumentHelpers};
 use dom::domstringmap::DOMStringMap;
 use dom::element::{Element, ElementTypeId, ActivationElementHelpers, AttributeHandlers};
 use dom::eventtarget::{EventTarget, EventTargetHelpers, EventTargetTypeId};
 use dom::htmlinputelement::HTMLInputElement;
 use dom::htmlmediaelement::HTMLMediaElementTypeId;
 use dom::htmltablecellelement::HTMLTableCellElementTypeId;
-use dom::node::{Node, NodeTypeId, window_from_node};
+use dom::node::{Node, NodeHelpers, NodeTypeId, document_from_node, window_from_node};
 use dom::virtualmethods::VirtualMethods;
 use dom::window::WindowHelpers;
 
@@ -135,6 +135,32 @@ impl<'a> HTMLElementMethods for JSRef<'a, HTMLElement> {
         // https://www.w3.org/Bugs/Public/show_bug.cgi?id=27430 ?
         element.as_maybe_activatable().map(|a| a.synthetic_click_activation(false, false, false, false));
     }
+
+    // https://html.spec.whatwg.org/multipage/interaction.html#dom-focus
+    fn Focus(self) {
+        // TODO: Mark the element as locked for focus and run the focusing steps.
+        // https://html.spec.whatwg.org/multipage/interaction.html#focusing-steps
+        let element: JSRef<Element> = ElementCast::from_ref(self);
+        let document = document_from_node(self).root();
+        let document = document.r();
+        document.begin_focus_transaction();
+        document.request_focus(element);
+        document.commit_focus_transaction();
+    }
+
+    // https://html.spec.whatwg.org/multipage/interaction.html#dom-blur
+    fn Blur(self) {
+        // TODO: Run the unfocusing steps.
+        let node: JSRef<Node> = NodeCast::from_ref(self);
+        if !node.get_focus_state() {
+            return;
+        }
+        // https://html.spec.whatwg.org/multipage/interaction.html#unfocusing-steps
+        let document = document_from_node(self).root();
+        document.r().begin_focus_transaction();
+        // If `request_focus` is not called, focus will be set to None.
+        document.r().commit_focus_transaction();
+    }
 }
 
 // https://html.spec.whatwg.org/#attr-data-*

servo/components/script/dom/node.rs

@@ -152,6 +152,8 @@ bitflags! {
         #[doc = "Specifies whether or not there is an authentic click in progress on \
                  this element."]
         const CLICK_IN_PROGRESS = 0x100,
+        #[doc = "Specifies whether this node has the focus."]
+        const IN_FOCUS_STATE = 0x200,
     }
 }
 
@@ -440,6 +442,9 @@ pub trait NodeHelpers<'a> {
     fn get_hover_state(self) -> bool;
     fn set_hover_state(self, state: bool);
 
+    fn get_focus_state(self) -> bool;
+    fn set_focus_state(self, state: bool);
+
     fn get_disabled_state(self) -> bool;
     fn set_disabled_state(self, state: bool);
 
@@ -618,6 +623,14 @@ impl<'a> NodeHelpers<'a> for JSRef<'a, Node> {
         self.set_flag(IN_HOVER_STATE, state)
     }
 
+    fn get_focus_state(self) -> bool {
+        self.get_flag(IN_FOCUS_STATE)
+    }
+
+    fn set_focus_state(self, state: bool) {
+        self.set_flag(IN_FOCUS_STATE, state)
+    }
+
     fn get_disabled_state(self) -> bool {
         self.get_flag(IN_DISABLED_STATE)
     }
@@ -1036,6 +1049,8 @@ pub trait RawLayoutNodeHelpers {
     #[allow(unsafe_code)]
     unsafe fn get_hover_state_for_layout(&self) -> bool;
     #[allow(unsafe_code)]
+    unsafe fn get_focus_state_for_layout(&self) -> bool;
+    #[allow(unsafe_code)]
     unsafe fn get_disabled_state_for_layout(&self) -> bool;
     #[allow(unsafe_code)]
     unsafe fn get_enabled_state_for_layout(&self) -> bool;
@@ -1050,6 +1065,11 @@ impl RawLayoutNodeHelpers for Node {
     }
     #[inline]
     #[allow(unsafe_code)]
+    unsafe fn get_focus_state_for_layout(&self) -> bool {
+        self.flags.get().contains(IN_FOCUS_STATE)
+    }
+    #[inline]
+    #[allow(unsafe_code)]
     unsafe fn get_disabled_state_for_layout(&self) -> bool {
         self.flags.get().contains(IN_DISABLED_STATE)
     }

servo/components/script/dom/webidls/HTMLElement.webidl

@@ -25,8 +25,8 @@ interface HTMLElement : Element {
            attribute boolean hidden;
   void click();
   //         attribute long tabIndex;
-  //void focus();
-  //void blur();
+  void focus();
+  void blur();
   //         attribute DOMString accessKey;
   //readonly attribute DOMString accessKeyLabel;
   //         attribute boolean draggable;

servo/components/servo/Cargo.lock

@@ -831,7 +831,7 @@ dependencies = [
 [[package]]
 name = "selectors"
 version = "0.1.0"
-source = "git+https://github.com/servo/rust-selectors#12d3ce84a12ded4cf1def63651ccab06e1cfa80e"
+source = "git+https://github.com/servo/rust-selectors#0d7d846090c21d71ebb1bc17921806933a38f52b"
 dependencies = [
  "bitflags 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.2.0 (git+https://github.com/servo/rust-cssparser)",

servo/ports/cef/Cargo.lock

@@ -104,6 +104,7 @@ dependencies = [
  "libc 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
  "net 0.0.1",
+ "net_traits 0.0.1",
  "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile 0.0.1",
  "script_traits 0.0.1",
@@ -327,7 +328,7 @@ dependencies = [
  "layers 0.1.0 (git+https://github.com/servo/rust-layers)",
  "libc 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
- "net 0.0.1",
+ "net_traits 0.0.1",
  "plugins 0.0.1",
  "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile 0.0.1",
@@ -533,7 +534,7 @@ dependencies = [
  "layout_traits 0.0.1",
  "libc 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
- "net 0.0.1",
+ "net_traits 0.0.1",
  "plugins 0.0.1",
  "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile 0.0.1",
@@ -554,7 +555,7 @@ version = "0.0.1"
 dependencies = [
  "gfx 0.0.1",
  "msg 0.0.1",
- "net 0.0.1",
+ "net_traits 0.0.1",
  "profile 0.0.1",
  "script_traits 0.0.1",
  "url 0.2.23 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -645,18 +646,31 @@ dependencies = [
  "flate2 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "geom 0.1.0 (git+https://github.com/servo/rust-geom)",
  "hyper 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "net_traits 0.0.1",
  "openssl 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile 0.0.1",
  "regex 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex_macros 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "stb_image 0.1.0 (git+https://github.com/servo/rust-stb-image)",
  "time 0.1.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.2.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
 ]
 
+[[package]]
+name = "net_traits"
+version = "0.0.1"
+dependencies = [
+ "geom 0.1.0 (git+https://github.com/servo/rust-geom)",
+ "hyper 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "png 0.1.0 (git+https://github.com/servo/rust-png)",
+ "profile 0.0.1",
+ "stb_image 0.1.0 (git+https://github.com/servo/rust-stb-image)",
+ "url 0.2.23 (registry+https://github.com/rust-lang/crates.io-index)",
+ "util 0.0.1",
+]
+
 [[package]]
 name = "openssl"
 version = "0.5.1"
@@ -791,7 +805,7 @@ dependencies = [
  "js 0.1.0 (git+https://github.com/servo/rust-mozjs)",
  "libc 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
- "net 0.0.1",
+ "net_traits 0.0.1",
  "plugins 0.0.1",
  "profile 0.0.1",
  "rustc-serialize 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -814,7 +828,7 @@ dependencies = [
  "geom 0.1.0 (git+https://github.com/servo/rust-geom)",
  "libc 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
- "net 0.0.1",
+ "net_traits 0.0.1",
  "url 0.2.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
 ]
@@ -822,7 +836,7 @@ dependencies = [
 [[package]]
 name = "selectors"
 version = "0.1.0"
-source = "git+https://github.com/servo/rust-selectors#12d3ce84a12ded4cf1def63651ccab06e1cfa80e"
+source = "git+https://github.com/servo/rust-selectors#0d7d846090c21d71ebb1bc17921806933a38f52b"
 dependencies = [
  "bitflags 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.2.0 (git+https://github.com/servo/rust-cssparser)",
@@ -843,6 +857,7 @@ dependencies = [
  "layout 0.0.1",
  "msg 0.0.1",
  "net 0.0.1",
+ "net_traits 0.0.1",
  "png 0.1.0 (git+https://github.com/servo/rust-png)",
  "profile 0.0.1",
  "script 0.0.1",

servo/ports/gonk/Cargo.lock

@@ -761,7 +761,7 @@ dependencies = [
 [[package]]
 name = "selectors"
 version = "0.1.0"
-source = "git+https://github.com/servo/rust-selectors#12d3ce84a12ded4cf1def63651ccab06e1cfa80e"
+source = "git+https://github.com/servo/rust-selectors#0d7d846090c21d71ebb1bc17921806933a38f52b"
 dependencies = [
  "bitflags 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.2.0 (git+https://github.com/servo/rust-cssparser)",

servo/tests/content/test_document_activeElement.html

@@ -10,10 +10,9 @@
             is_not(document.activeElement, null, "test_1.1, document.activeElement");
             is(document.activeElement, document.body, "test_1.2, document.activeElement");
 
-            //TODO: uncomment following lines when focus() method will be available
-            //document.getElementById('foo').focus();
+            document.getElementById('foo').focus();
             is_not(document.activeElement, null, "test_2.1, document.activeElement");
-            //is(document.activeElement, document.getElementById("foo"), "test_2.2, document.activeElement");
+            is(document.activeElement, document.getElementById("foo"), "test_2.2, document.activeElement");
         </script>
     </body>
 </html>

servo/tests/content/test_focus_blur.html

@@ -0,0 +1,25 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="UTF-8">
+  <script src="harness.js"></script>
+</head>
+<body>
+  <input id="a">
+  <input id="b">
+  <script>
+    var a = document.getElementById("a");
+    var b = document.getElementById("b");
+
+    is(document.activeElement, document.body);
+    a.focus();
+    is(document.activeElement, a);
+    b.focus();
+    is(document.activeElement, b);
+    a.blur();
+    is(document.activeElement, b);
+    b.blur();
+    is(document.activeElement, document.body);
+  </script>
+</body>
+</html>