layout_2020: Add support for transitions and animations

components/layout_2020/Cargo.toml

@@ -20,6 +20,7 @@ cssparser = "0.27"
 embedder_traits = { path = "../embedder_traits" }
 euclid = "0.20"
 fnv = "1.0"
+fxhash = "0.2"
 gfx = { path = "../gfx" }
 gfx_traits = { path = "../gfx_traits" }
 html5ever = "0.25"

components/layout_2020/flow/root.rs

@@ -26,6 +26,7 @@ use crate::style_ext::{Display, DisplayGeneratingBox};
 use crate::DefiniteContainingBlock;
 use app_units::Au;
 use euclid::default::{Point2D, Rect, Size2D};
+use fxhash::FxHashSet;
 use gfx_traits::print_tree::PrintTree;
 use script_layout_interface::wrapper_traits::LayoutNode;
 use script_layout_interface::{LayoutElementType, LayoutNodeType};
@@ -303,6 +304,15 @@ impl FragmentTree {
         })
     }
 
+    pub fn remove_nodes_in_fragment_tree_from_set(&self, set: &mut FxHashSet<OpaqueNode>) {
+        self.find(|fragment, _| {
+            if let Some(tag) = fragment.tag().as_ref() {
+                set.remove(tag);
+            }
+            None::<()>
+        });
+    }
+
     pub fn get_content_box_for_node(&self, requested_node: OpaqueNode) -> Rect<Au> {
         let mut bounding_box = PhysicalRect::zero();
         self.find(|fragment, containing_block| {

components/layout_thread_2020/lib.rs

@@ -27,7 +27,7 @@ use crossbeam_channel::{Receiver, Sender};
 use embedder_traits::resources::{self, Resource};
 use euclid::{default::Size2D as UntypedSize2D, Point2D, Rect, Scale, Size2D};
 use fnv::FnvHashMap;
-use fxhash::FxHashMap;
+use fxhash::{FxHashMap, FxHashSet};
 use gfx::font_cache_thread::FontCacheThread;
 use gfx::font_context;
 use gfx_traits::{node_id_from_scroll_id, Epoch};
@@ -80,9 +80,11 @@ use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
 use std::sync::{Arc, Mutex, MutexGuard};
 use std::thread;
 use std::time::Duration;
+use style::animation::ElementAnimationSet;
 use style::context::{
     QuirksMode, RegisteredSpeculativePainter, RegisteredSpeculativePainters, SharedStyleContext,
 };
+use style::dom::OpaqueNode;
 use style::dom::{TDocument, TElement, TNode};
 use style::driver;
 use style::error_reporting::RustLogReporter;
@@ -572,6 +574,7 @@ impl LayoutThread {
         snapshot_map: &'a SnapshotMap,
         origin: ImmutableOrigin,
         animation_timeline_value: f64,
+        animation_states: ServoArc<RwLock<FxHashMap<OpaqueNode, ElementAnimationSet>>>,
     ) -> LayoutContext<'a> {
         LayoutContext {
             id: self.id,
@@ -581,7 +584,7 @@ impl LayoutThread {
                 options: GLOBAL_STYLE_DATA.options.clone(),
                 guards,
                 visited_styles_enabled: false,
-                animation_states: Default::default(),
+                animation_states,
                 registered_speculative_painters: &self.registered_painters,
                 current_time_for_animations: animation_timeline_value,
                 traversal_flags: TraversalFlags::empty(),
@@ -1062,8 +1065,13 @@ impl LayoutThread {
         self.stylist.flush(&guards, Some(element), Some(&map));
 
         // Create a layout context for use throughout the following passes.
-        let mut layout_context =
-            self.build_layout_context(guards.clone(), &map, origin, data.animation_timeline_value);
+        let mut layout_context = self.build_layout_context(
+            guards.clone(),
+            &map,
+            origin,
+            data.animation_timeline_value,
+            data.animations.clone(),
+        );
 
         let traversal = RecalcStyle::new(layout_context);
         let token = {
@@ -1273,6 +1281,11 @@ impl LayoutThread {
         document: Option<&ServoLayoutDocument>,
         context: &mut LayoutContext,
     ) {
+        Self::cancel_animations_for_nodes_not_in_fragment_tree(
+            &mut *(context.style_context.animation_states.write()),
+            &fragment_tree,
+        );
+
         if self.trace_layout {
             if let Some(box_tree) = &*self.box_tree.borrow() {
                 layout_debug::begin_trace(box_tree.clone(), fragment_tree.clone());
@@ -1356,6 +1369,25 @@ impl LayoutThread {
             },
         })
     }
+
+    /// Cancel animations for any nodes which have been removed from fragment tree.
+    /// TODO(mrobinson): We should look into a way of doing this during flow tree construction.
+    /// This also doesn't yet handles nodes that have been reparented.
+    fn cancel_animations_for_nodes_not_in_fragment_tree(
+        animation_states: &mut FxHashMap<OpaqueNode, ElementAnimationSet>,
+        root: &FragmentTree,
+    ) {
+        // Assume all nodes have been removed until proven otherwise.
+        let mut invalid_nodes: FxHashSet<OpaqueNode> = animation_states.keys().cloned().collect();
+        root.remove_nodes_in_fragment_tree_from_set(&mut invalid_nodes);
+
+        // Cancel animations for any nodes that are no longer in the fragment tree.
+        for node in &invalid_nodes {
+            if let Some(state) = animation_states.get_mut(node) {
+                state.cancel_all_animations();
+            }
+        }
+    }
 }
 
 impl ProfilerMetadataFactory for LayoutThread {

components/style/properties/longhands/box.mako.rs

@@ -161,7 +161,6 @@ ${helpers.predefined_type(
     "Time",
     "computed::Time::zero()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::Time::zero()",
     parse_method="parse_non_negative",
     vector=True,
@@ -176,7 +175,6 @@ ${helpers.predefined_type(
     "TimingFunction",
     "computed::TimingFunction::ease()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::TimingFunction::ease()",
     vector=True,
     need_index=True,
@@ -190,7 +188,6 @@ ${helpers.predefined_type(
     "TransitionProperty",
     "computed::TransitionProperty::all()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::TransitionProperty::all()",
     vector=True,
     allow_empty="NotInitial",
@@ -205,7 +202,6 @@ ${helpers.predefined_type(
     "Time",
     "computed::Time::zero()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::Time::zero()",
     vector=True,
     need_index=True,
@@ -221,7 +217,6 @@ ${helpers.predefined_type(
     "AnimationName",
     "computed::AnimationName::none()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::AnimationName::none()",
     vector=True,
     need_index=True,
@@ -236,7 +231,6 @@ ${helpers.predefined_type(
     "Time",
     "computed::Time::zero()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::Time::zero()",
     parse_method="parse_non_negative",
     vector=True,
@@ -253,7 +247,6 @@ ${helpers.predefined_type(
     "TimingFunction",
     "computed::TimingFunction::ease()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::TimingFunction::ease()",
     vector=True,
     need_index=True,
@@ -268,7 +261,6 @@ ${helpers.predefined_type(
     "AnimationIterationCount",
     "computed::AnimationIterationCount::one()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::AnimationIterationCount::one()",
     vector=True,
     need_index=True,
@@ -283,7 +275,6 @@ ${helpers.single_keyword(
     "animation-direction",
     "normal reverse alternate alternate-reverse",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     need_index=True,
     animation_value_type="none",
     vector=True,
@@ -299,7 +290,6 @@ ${helpers.single_keyword(
     "animation-play-state",
     "running paused",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     need_index=True,
     animation_value_type="none",
     vector=True,
@@ -328,7 +318,6 @@ ${helpers.predefined_type(
     "Time",
     "computed::Time::zero()",
     engines="gecko servo-2013 servo-2020",
-    servo_2020_pref="layout.2020.unimplemented",
     initial_specified_value="specified::Time::zero()",
     vector=True,
     need_index=True,

components/style/properties/shorthands/box.mako.rs

@@ -28,7 +28,6 @@ ${helpers.two_properties_shorthand(
          "(https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-clip-box)",
 )}
 
-#[cfg(any(feature = "gecko", feature = "servo-layout-2013"))]
 macro_rules! try_parse_one {
     ($context: expr, $input: expr, $var: ident, $prop_module: ident) => {
         if $var.is_none() {
@@ -43,7 +42,7 @@ macro_rules! try_parse_one {
 }
 
 <%helpers:shorthand name="transition"
-                    engines="gecko servo-2013"
+                    engines="gecko servo-2013 servo-2020"
                     extra_prefixes="moz:layout.css.prefixes.transitions webkit"
                     sub_properties="transition-property transition-duration
                                     transition-timing-function
@@ -189,7 +188,7 @@ macro_rules! try_parse_one {
 </%helpers:shorthand>
 
 <%helpers:shorthand name="animation"
-                    engines="gecko servo-2013"
+                    engines="gecko servo-2013 servo-2020"
                     extra_prefixes="moz:layout.css.prefixes.animations webkit"
                     sub_properties="animation-name animation-duration
                                     animation-timing-function animation-delay

tests/wpt/include-layout-2020.ini

@@ -9,6 +9,8 @@ skip: true
   skip: true
   [CSS2]
     skip: false
+  [css-animations]
+    skip: false
   [css-backgrounds]
     skip: false
   [css-content]
@@ -23,6 +25,8 @@ skip: true
     skip: false
   [css-transforms]
     skip: false
+  [css-transitions]
+    skip: false
   [css-ui]
     skip: false
   [filter-effects]