script: Implement Range::getClientRects and Range::getBoundingClientRect (#35993)

* Add doc comments to boundary point

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

* Allow querying content box of text fragments

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

* Implement Range::getBoundingClientRect

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

* Update WPT expectations

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

---------

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

components/layout_2020/fragment_tree/fragment_tree.rs

@@ -155,6 +155,7 @@ impl FragmentTree {
                     }
                 },
                 Fragment::Positioning(fragment) => fragment.borrow().rect.cast_unit(),
+                Fragment::Text(text_fragment) => text_fragment.borrow().rect,
                 _ => return None,
             };
 

components/script/dom/abstractrange.rs

@@ -94,10 +94,13 @@ impl AbstractRangeMethods<crate::DomTypeHolder> for AbstractRange {
     }
 }
 
+/// <https://dom.spec.whatwg.org/#concept-range-bp>
 #[derive(DenyPublicFields, JSTraceable, MallocSizeOf)]
 #[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
 pub(crate) struct BoundaryPoint {
+    /// <https://dom.spec.whatwg.org/#boundary-point-node>
     node: MutDom<Node>,
+    /// <https://dom.spec.whatwg.org/#concept-range-bp-offset>
     offset: Cell<u32>,
 }
 

components/script/dom/range.rs

@@ -4,6 +4,7 @@
 
 use std::cell::UnsafeCell;
 use std::cmp::{Ordering, PartialOrd};
+use std::iter;
 
 use dom_struct::dom_struct;
 use js::jsapi::JSTracer;
@@ -29,9 +30,11 @@ use crate::dom::bindings::weakref::{WeakRef, WeakRefVec};
 use crate::dom::characterdata::CharacterData;
 use crate::dom::document::Document;
 use crate::dom::documentfragment::DocumentFragment;
+use crate::dom::domrect::DOMRect;
+use crate::dom::domrectlist::DOMRectList;
 use crate::dom::element::Element;
 use crate::dom::htmlscriptelement::HTMLScriptElement;
-use crate::dom::node::{Node, ShadowIncluding, UnbindContext};
+use crate::dom::node::{Node, NodeTraits, ShadowIncluding, UnbindContext};
 use crate::dom::selection::Selection;
 use crate::dom::text::Text;
 use crate::dom::window::Window;
@@ -324,6 +327,23 @@ impl Range {
     pub(crate) fn collapsed(&self) -> bool {
         self.abstract_range().Collapsed()
     }
+
+    fn client_rects(
+        &self,
+        can_gc: CanGc,
+    ) -> impl Iterator<Item = euclid::Rect<app_units::Au, euclid::UnknownUnit>> {
+        // FIXME: For text nodes that are only partially selected, this should return the client
+        // rect of the selected part, not the whole text node.
+        let start = self.start_container();
+        let end = self.end_container();
+        let document = start.owner_doc();
+        let end_clone = end.clone();
+        start
+            .following_nodes(document.upcast::<Node>())
+            .take_while(move |node| node != &end)
+            .chain(iter::once(end_clone))
+            .flat_map(move |node| node.content_boxes(can_gc))
+    }
 }
 
 impl RangeMethods<crate::DomTypeHolder> for Range {
@@ -1105,6 +1125,51 @@ impl RangeMethods<crate::DomTypeHolder> for Range {
         // Step 5.
         Ok(fragment_node)
     }
+
+    /// <https://drafts.csswg.org/cssom-view/#dom-range-getclientrects>
+    fn GetClientRects(&self, can_gc: CanGc) -> DomRoot<DOMRectList> {
+        let start = self.start_container();
+        let window = start.owner_window();
+
+        let client_rects = self
+            .client_rects(can_gc)
+            .map(|rect| {
+                DOMRect::new(
+                    window.upcast(),
+                    rect.origin.x.to_f64_px(),
+                    rect.origin.y.to_f64_px(),
+                    rect.size.width.to_f64_px(),
+                    rect.size.height.to_f64_px(),
+                    can_gc,
+                )
+            })
+            .collect();
+
+        DOMRectList::new(&window, client_rects, can_gc)
+    }
+
+    /// <https://drafts.csswg.org/cssom-view/#dom-range-getboundingclientrect>
+    fn GetBoundingClientRect(&self, can_gc: CanGc) -> DomRoot<DOMRect> {
+        let window = self.start_container().owner_window();
+
+        // Step 1. Let list be the result of invoking getClientRects() on the same range this method was invoked on.
+        let list = self.client_rects(can_gc);
+
+        // Step 2. If list is empty return a DOMRect object whose x, y, width and height members are zero.
+        // Step 3. If all rectangles in list have zero width or height, return the first rectangle in list.
+        // Step 4. Otherwise, return a DOMRect object describing the smallest rectangle that includes all
+        // of the rectangles in list of which the height or width is not zero.
+        let bounding_rect = list.fold(euclid::Rect::zero(), |acc, rect| acc.union(&rect));
+
+        DOMRect::new(
+            window.upcast(),
+            bounding_rect.origin.x.to_f64_px(),
+            bounding_rect.origin.y.to_f64_px(),
+            bounding_rect.size.width.to_f64_px(),
+            bounding_rect.size.height.to_f64_px(),
+            can_gc,
+        )
+    }
 }
 
 pub(crate) struct WeakRangeVec {

components/script_bindings/codegen/Bindings.conf

@@ -469,7 +469,7 @@ DOMInterfaces = {
 },
 
 'Range': {
-    'canGc': ['CloneContents', 'CloneRange', 'CreateContextualFragment', 'ExtractContents', 'SurroundContents', 'InsertNode'],
+    'canGc': ['CloneContents', 'CloneRange', 'CreateContextualFragment', 'ExtractContents', 'SurroundContents', 'InsertNode', 'GetClientRects', 'GetBoundingClientRect'],
     'weakReferenceable': True,
 },
 

components/script_bindings/webidls/Range.webidl

@@ -73,7 +73,6 @@ partial interface Range {
 
 // http://dev.w3.org/csswg/cssom-view/#extensions-to-the-range-interface
 partial interface Range {
-  // sequence<DOMRect> getClientRects();
-  // [NewObject]
-  // DOMRect getBoundingClientRect();
+  DOMRectList getClientRects();
+  [NewObject] DOMRect getBoundingClientRect();
 };

tests/wpt/meta/css/cssom-view/DOMRectList.html.ini

@@ -1,3 +0,0 @@
-[DOMRectList.html]
-  [Range getClientRects()]
-    expected: FAIL

tests/wpt/meta/css/cssom-view/getBoundingClientRect-svg.html.ini

@@ -1,9 +0,0 @@
-[getBoundingClientRect-svg.html]
-  [Element.getBoundingClientRect() and Range.getBoudingClientRect() should match for an SVG <text>]
-    expected: FAIL
-
-  [Element.getBoundingClientRect() and Range.getBoudingClientRect() should match for an SVG <text> with a transform]
-    expected: FAIL
-
-  [Element.getBoundingClientRect() and Range.getBoudingClientRect() should match for an SVG <text> with a rotate]
-    expected: FAIL

tests/wpt/meta/css/cssom-view/idlharness.html.ini

@@ -26,9 +26,6 @@
   [Element interface: document.createElement("div") must inherit property "getBoxQuads(BoxQuadOptions)" with the proper type]
     expected: FAIL
 
-  [Range interface: new Range() must inherit property "getBoundingClientRect()" with the proper type]
-    expected: FAIL
-
   [Element interface: calling convertRectFromNode(DOMRectReadOnly, GeometryNode, ConvertCoordinateOptions) on document.createElementNS("x", "y") with too few arguments must throw TypeError]
     expected: FAIL
 
@@ -62,9 +59,6 @@
   [CaretPosition interface: attribute offset]
     expected: FAIL
 
-  [Range interface: operation getBoundingClientRect()]
-    expected: FAIL
-
   [Partial dictionary MouseEventInit: member names are unique]
     expected: FAIL
 
@@ -98,9 +92,6 @@
   [CaretPosition interface: existence and properties of interface prototype object]
     expected: FAIL
 
-  [Range interface: operation getClientRects()]
-    expected: FAIL
-
   [Element interface: document.createElementNS("x", "y") must inherit property "convertRectFromNode(DOMRectReadOnly, GeometryNode, ConvertCoordinateOptions)" with the proper type]
     expected: FAIL
 
@@ -272,9 +263,6 @@
   [Element interface: document.createElement("img") must inherit property "convertPointFromNode(DOMPointInit, GeometryNode, ConvertCoordinateOptions)" with the proper type]
     expected: FAIL
 
-  [Range interface: new Range() must inherit property "getClientRects()" with the proper type]
-    expected: FAIL
-
   [Window interface: window must inherit property "screenLeft" with the proper type]
     expected: FAIL