Auto merge of #6662 - tschneidereit:client-geometry, r=glennw,pcwatson

Implement Element.client{Top,Left,Width,Height}

This isn't done, but contains a working implementation of at least `clientTop`. Feedback would be much appreciated: it's probably far from ideal.

Implementing `clientLeft` is straight-forward, I think, but `clientWidth` and `clientHeight` require accessing the `border_box` - and I don't know how that works, yet.

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4 files changed, 39 insertions, 0 deletions

diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index dd6afd3061b..10b7950f82e 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -1317,6 +1317,26 @@ impl<'a> ElementMethods for &'a Element {
             rect.origin.x + rect.size.width)
     }
 
+    fn ClientTop(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().origin.y
+    }
+
+    fn ClientLeft(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().origin.x
+    }
+
+    fn ClientWidth(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().size.width
+    }
+
+    fn ClientHeight(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().size.height
+    }
+
     // https://dvcs.w3.org/hg/innerhtml/raw-file/tip/index.html#widl-Element-innerHTML
     fn GetInnerHTML(self) -> Fallible<DOMString> {
         //XXX TODO: XML case
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 42ad7608580..54535fdb7af 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -492,6 +492,7 @@ pub trait NodeHelpers {
 
     fn get_bounding_content_box(self) -> Rect<Au>;
     fn get_content_boxes(self) -> Vec<Rect<Au>>;
+    fn get_client_rect(self) -> Rect<i32>;
 
     fn before(self, nodes: Vec<NodeOrString>) -> ErrorResult;
     fn after(self, nodes: Vec<NodeOrString>) -> ErrorResult;
@@ -794,6 +795,10 @@ impl<'a> NodeHelpers for &'a Node {
         window_from_node(self).r().content_boxes_query(self.to_trusted_node_address())
     }
 
+    fn get_client_rect(self) -> Rect<i32> {
+        window_from_node(self).r().client_rect_query(self.to_trusted_node_address())
+    }
+
     // https://dom.spec.whatwg.org/#dom-childnode-before
     fn before(self, nodes: Vec<NodeOrString>) -> ErrorResult {
         match self.parent_node.get() {
diff --git a/components/script/dom/webidls/Element.webidl b/components/script/dom/webidls/Element.webidl
index 81c6f329b47..f2f18a5cc0b 100644
--- a/components/script/dom/webidls/Element.webidl
+++ b/components/script/dom/webidls/Element.webidl
@@ -59,6 +59,11 @@ interface Element : Node {
 partial interface Element {
   DOMRectList getClientRects();
   DOMRect getBoundingClientRect();
+
+  readonly attribute long clientTop;
+  readonly attribute long clientLeft;
+  readonly attribute long clientWidth;
+  readonly attribute long clientHeight;
 };
 
 // https://domparsing.spec.whatwg.org/#extensions-to-the-element-interface
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 04f6b3ee6ce..7bea165b46d 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -540,6 +540,7 @@ pub trait WindowHelpers {
     fn layout(&self) -> &LayoutRPC;
     fn content_box_query(self, content_box_request: TrustedNodeAddress) -> Rect<Au>;
     fn content_boxes_query(self, content_boxes_request: TrustedNodeAddress) -> Vec<Rect<Au>>;
+    fn client_rect_query(self, node_geometry_request: TrustedNodeAddress) -> Rect<i32>;
     fn handle_reflow_complete_msg(self, reflow_id: u32);
     fn set_fragment_name(self, fragment: Option<String>);
     fn steal_fragment_name(self) -> Option<String>;
@@ -771,6 +772,13 @@ impl<'a> WindowHelpers for &'a Window {
         rects
     }
 
+    fn client_rect_query(self, node_geometry_request: TrustedNodeAddress) -> Rect<i32> {
+        self.reflow(ReflowGoal::ForScriptQuery,
+                    ReflowQueryType::NodeGeometryQuery(node_geometry_request),
+                    ReflowReason::Query);
+        self.layout_rpc.node_geometry().client_rect
+    }
+
     fn handle_reflow_complete_msg(self, reflow_id: u32) {
         let last_reflow_id = self.last_reflow_id.get();
         if last_reflow_id == reflow_id {
@@ -1077,6 +1085,7 @@ fn debug_reflow_events(goal: &ReflowGoal, query_type: &ReflowQueryType, reason:
         ReflowQueryType::NoQuery => "\tNoQuery",
         ReflowQueryType::ContentBoxQuery(_n) => "\tContentBoxQuery",
         ReflowQueryType::ContentBoxesQuery(_n) => "\tContentBoxesQuery",
+        ReflowQueryType::NodeGeometryQuery(_n) => "\tNodeGeometryQuery",
     });
 
     debug_msg.push_str(match *reason {