Auto merge of #6940 - pcwalton:inline-pseudo-repair-jumpiness, r=mbrubeck

layout: When repairing styles for incremental reflow, only repair styles of nodes that represent the dirty node, *including its pseudo-element*.

r? @mbrubeck

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6 files changed, 55 insertions, 13 deletions

diff --git a/components/layout/construct.rs b/components/layout/construct.rs
index 9ab1dfc6675..5060eaa3bbd 100644
--- a/components/layout/construct.rs
+++ b/components/layout/construct.rs
@@ -105,7 +105,7 @@ pub enum ConstructionItem {
     /// Inline fragments and associated {ib} splits that have not yet found flows.
     InlineFragments(InlineFragmentsConstructionResult),
     /// Potentially ignorable whitespace.
-    Whitespace(OpaqueNode, Arc<ComputedValues>, RestyleDamage),
+    Whitespace(OpaqueNode, PseudoElementType<()>, Arc<ComputedValues>, RestyleDamage),
     /// TableColumn Fragment
     TableColumnFragment(Fragment),
 }
@@ -217,6 +217,7 @@ impl InlineFragmentsAccumulator {
             fragments: IntermediateInlineFragments::new(),
             enclosing_node: Some(InlineFragmentNodeInfo {
                 address: node.opaque(),
+                pseudo: node.get_pseudo_element_type().strip(),
                 style: node.style().clone(),
             }),
             bidi_control_chars: None,
@@ -573,6 +574,7 @@ impl<'a> FlowConstructor<'a> {
             }
             ConstructionResult::ConstructionItem(ConstructionItem::Whitespace(
                     whitespace_node,
+                    whitespace_pseudo,
                     mut whitespace_style,
                     whitespace_damage)) => {
                 // Add whitespace results. They will be stripped out later on when
@@ -581,6 +583,7 @@ impl<'a> FlowConstructor<'a> {
                     UnscannedTextFragmentInfo::from_text(" ".to_owned()));
                 properties::modify_style_for_replaced_content(&mut whitespace_style);
                 let fragment = Fragment::from_opaque_node_and_style(whitespace_node,
+                                                                    whitespace_pseudo,
                                                                     whitespace_style,
                                                                     whitespace_damage,
                                                                     fragment_info);
@@ -712,6 +715,8 @@ impl<'a> FlowConstructor<'a> {
 
             fragments.fragments
                      .push_back(Fragment::from_opaque_node_and_style(node.opaque(),
+                                                                     node.get_pseudo_element_type()
+                                                                         .strip(),
                                                                      style.clone(),
                                                                      node.restyle_damage(),
                                                                      specific))
@@ -793,12 +798,14 @@ impl<'a> FlowConstructor<'a> {
                     } else {
                         // Push the absolutely-positioned kid as an inline containing block.
                         let kid_node = flow.as_block().fragment.node;
+                        let kid_pseudo = flow.as_block().fragment.pseudo.clone();
                         let kid_style = flow.as_block().fragment.style.clone();
                         let kid_restyle_damage = flow.as_block().fragment.restyle_damage;
                         let fragment_info = SpecificFragmentInfo::InlineAbsolute(
                             InlineAbsoluteFragmentInfo::new(flow));
                         fragment_accumulator.push(Fragment::from_opaque_node_and_style(
                                 kid_node,
+                                kid_pseudo,
                                 kid_style,
                                 kid_restyle_damage,
                                 fragment_info));
@@ -826,6 +833,7 @@ impl<'a> FlowConstructor<'a> {
                 }
                 ConstructionResult::ConstructionItem(ConstructionItem::Whitespace(
                         whitespace_node,
+                        whitespace_pseudo,
                         mut whitespace_style,
                         whitespace_damage)) => {
                     // Instantiate the whitespace fragment.
@@ -833,6 +841,7 @@ impl<'a> FlowConstructor<'a> {
                         UnscannedTextFragmentInfo::from_text(" ".to_owned()));
                     properties::modify_style_for_replaced_content(&mut whitespace_style);
                     let fragment = Fragment::from_opaque_node_and_style(whitespace_node,
+                                                                        whitespace_pseudo,
                                                                         whitespace_style,
                                                                         whitespace_damage,
                                                                         fragment_info);
@@ -875,6 +884,7 @@ impl<'a> FlowConstructor<'a> {
         if node.is_ignorable_whitespace() {
             return ConstructionResult::ConstructionItem(ConstructionItem::Whitespace(
                 node.opaque(),
+                node.get_pseudo_element_type().strip(),
                 node.style().clone(),
                 node.restyle_damage()))
         }
@@ -1295,10 +1305,14 @@ impl<'a> FlowConstructor<'a> {
                 for fragment in inline_fragments_construction_result.fragments
                                                                     .fragments
                                                                     .iter_mut() {
-                    // Only mutate the styles of fragments that represent the dirty node.
+                    // Only mutate the styles of fragments that represent the dirty node (including
+                    // pseudo-element).
                     if fragment.node != node.opaque() {
                         continue
                     }
+                    if fragment.pseudo != node.get_pseudo_element_type().strip() {
+                        continue
+                    }
 
                     match fragment.specific {
                         SpecificFragmentInfo::InlineBlock(ref mut inline_block_fragment) => {
@@ -1689,6 +1703,7 @@ fn control_chars_to_fragment(node: &InlineFragmentNodeInfo, text: &str,
     let info = SpecificFragmentInfo::UnscannedText(
         UnscannedTextFragmentInfo::from_text(String::from(text)));
     Fragment::from_opaque_node_and_style(node.address,
+                                         node.pseudo,
                                          node.style.clone(),
                                          restyle_damage,
                                          info)
diff --git a/components/layout/fragment.rs b/components/layout/fragment.rs
index 61a6042b6df..1f7ecce5fe9 100644
--- a/components/layout/fragment.rs
+++ b/components/layout/fragment.rs
@@ -17,7 +17,7 @@ use inline::{InlineFragmentContext, InlineFragmentNodeInfo, InlineMetrics};
 use layout_debug;
 use model::{self, IntrinsicISizes, IntrinsicISizesContribution, MaybeAuto, specified};
 use text;
-use wrapper::ThreadSafeLayoutNode;
+use wrapper::{PseudoElementType, ThreadSafeLayoutNode};
 
 use euclid::{Point2D, Rect, Size2D};
 use gfx::display_list::{BLUR_INFLATION_FACTOR, OpaqueNode};
@@ -107,6 +107,9 @@ pub struct Fragment {
     /// How damaged this fragment is since last reflow.
     pub restyle_damage: RestyleDamage,
 
+    /// The pseudo-element that this fragment represents.
+    pub pseudo: PseudoElementType<()>,
+
     /// A debug ID that is consistent for the life of this fragment (via transform etc).
     pub debug_id: u16,
 }
@@ -752,6 +755,7 @@ impl Fragment {
             margin: LogicalMargin::zero(writing_mode),
             specific: specific,
             inline_context: None,
+            pseudo: node.get_pseudo_element_type().strip(),
             debug_id: layout_debug::generate_unique_debug_id(),
         }
     }
@@ -782,12 +786,14 @@ impl Fragment {
             margin: LogicalMargin::zero(writing_mode),
             specific: specific,
             inline_context: None,
+            pseudo: node.get_pseudo_element_type().strip(),
             debug_id: layout_debug::generate_unique_debug_id(),
         }
     }
 
     /// Constructs a new `Fragment` instance from an opaque node.
     pub fn from_opaque_node_and_style(node: OpaqueNode,
+                                      pseudo: PseudoElementType<()>,
                                       style: Arc<ComputedValues>,
                                       restyle_damage: RestyleDamage,
                                       specific: SpecificFragmentInfo)
@@ -802,6 +808,7 @@ impl Fragment {
             margin: LogicalMargin::zero(writing_mode),
             specific: specific,
             inline_context: None,
+            pseudo: pseudo,
             debug_id: layout_debug::generate_unique_debug_id(),
         }
     }
@@ -834,6 +841,7 @@ impl Fragment {
             margin: self.margin,
             specific: info,
             inline_context: self.inline_context.clone(),
+            pseudo: self.pseudo.clone(),
             debug_id: self.debug_id,
         }
     }
diff --git a/components/layout/generated_content.rs b/components/layout/generated_content.rs
index a5803d2484c..6e9f5da9918 100644
--- a/components/layout/generated_content.rs
+++ b/components/layout/generated_content.rs
@@ -15,6 +15,7 @@ use fragment::{Fragment, GeneratedContentInfo, SpecificFragmentInfo, UnscannedTe
 use incremental::{self, RESOLVE_GENERATED_CONTENT};
 use smallvec::SmallVec;
 use text::TextRunScanner;
+use wrapper::PseudoElementType;
 
 use gfx::display_list::OpaqueNode;
 use std::collections::{LinkedList, HashMap};
@@ -174,6 +175,7 @@ impl<'a,'b> ResolveGeneratedContentFragmentMutator<'a,'b> {
                 GeneratedContentInfo::ListItem => {
                     new_info = self.traversal.list_item.render(self.traversal.layout_context,
                                                                fragment.node,
+                                                               fragment.pseudo.clone(),
                                                                fragment.style.clone(),
                                                                list_style_type,
                                                                RenderingMode::Suffix(".\u{00a0}"))
@@ -190,6 +192,7 @@ impl<'a,'b> ResolveGeneratedContentFragmentMutator<'a,'b> {
                                       .unwrap_or(&mut temporary_counter);
                     new_info = counter.render(self.traversal.layout_context,
                                               fragment.node,
+                                              fragment.pseudo.clone(),
                                               fragment.style.clone(),
                                               counter_style,
                                               RenderingMode::Plain)
@@ -204,6 +207,7 @@ impl<'a,'b> ResolveGeneratedContentFragmentMutator<'a,'b> {
                                       .unwrap_or(&mut temporary_counter);
                     new_info = counter.render(self.traversal.layout_context,
                                               fragment.node,
+                                              fragment.pseudo,
                                               fragment.style.clone(),
                                               counter_style,
                                               RenderingMode::All(&separator));
@@ -211,6 +215,7 @@ impl<'a,'b> ResolveGeneratedContentFragmentMutator<'a,'b> {
                 GeneratedContentInfo::ContentItem(ContentItem::OpenQuote) => {
                     new_info = Some(render_text(self.traversal.layout_context,
                                                 fragment.node,
+                                                fragment.pseudo,
                                                 fragment.style.clone(),
                                                 self.quote(&*fragment.style, false)));
                     self.traversal.quote += 1
@@ -222,6 +227,7 @@ impl<'a,'b> ResolveGeneratedContentFragmentMutator<'a,'b> {
 
                     new_info = Some(render_text(self.traversal.layout_context,
                                                 fragment.node,
+                                                fragment.pseudo,
                                                 fragment.style.clone(),
                                                 self.quote(&*fragment.style, true)));
                 }
@@ -356,6 +362,7 @@ impl Counter {
     fn render(&self,
               layout_context: &LayoutContext,
               node: OpaqueNode,
+              pseudo: PseudoElementType<()>,
               style: Arc<ComputedValues>,
               list_style_type: list_style_type::T,
               mode: RenderingMode)
@@ -392,7 +399,7 @@ impl Counter {
         if string.is_empty() {
             None
         } else {
-            Some(render_text(layout_context, node, style, string))
+            Some(render_text(layout_context, node, pseudo, style, string))
         }
     }
 }
@@ -418,12 +425,14 @@ struct CounterValue {
 /// Creates fragment info for a literal string.
 fn render_text(layout_context: &LayoutContext,
                node: OpaqueNode,
+               pseudo: PseudoElementType<()>,
                style: Arc<ComputedValues>,
                string: String)
                -> SpecificFragmentInfo {
     let mut fragments = LinkedList::new();
     let info = SpecificFragmentInfo::UnscannedText(UnscannedTextFragmentInfo::from_text(string));
     fragments.push_back(Fragment::from_opaque_node_and_style(node,
+                                                             pseudo,
                                                              style,
                                                              incremental::rebuild_and_reflow(),
                                                              info));
diff --git a/components/layout/inline.rs b/components/layout/inline.rs
index 6d4d67e6bbb..78363d0451c 100644
--- a/components/layout/inline.rs
+++ b/components/layout/inline.rs
@@ -15,6 +15,7 @@ use incremental::{REFLOW, REFLOW_OUT_OF_FLOW, RESOLVE_GENERATED_CONTENT};
 use layout_debug;
 use model::IntrinsicISizesContribution;
 use text;
+use wrapper::PseudoElementType;
 
 use euclid::{Point2D, Rect, Size2D};
 use gfx::display_list::OpaqueNode;
@@ -1349,8 +1350,7 @@ impl Flow for InlineFlow {
             self.base.block_container_explicit_block_size;
         for fragment in self.fragments.fragments.iter_mut() {
             fragment.update_late_computed_replaced_inline_size_if_necessary();
-            fragment.assign_replaced_block_size_if_necessary(
-                containing_block_block_size);
+            fragment.assign_replaced_block_size_if_necessary(containing_block_block_size);
         }
 
         // Reset our state, so that we handle incremental reflow correctly.
@@ -1687,6 +1687,7 @@ impl fmt::Debug for InlineFlow {
 pub struct InlineFragmentNodeInfo {
     pub address: OpaqueNode,
     pub style: Arc<ComputedValues>,
+    pub pseudo: PseudoElementType<()>,
 }
 
 #[derive(Clone)]
diff --git a/components/layout/wrapper.rs b/components/layout/wrapper.rs
index 26378daf40c..93e52192d64 100644
--- a/components/layout/wrapper.rs
+++ b/components/layout/wrapper.rs
@@ -588,13 +588,13 @@ impl<'le> TElementAttributes for LayoutElement<'le> {
 }
 
 #[derive(Copy, PartialEq, Clone)]
-pub enum PseudoElementType {
+pub enum PseudoElementType<T> {
     Normal,
-    Before(display::T),
-    After(display::T),
+    Before(T),
+    After(T),
 }
 
-impl PseudoElementType {
+impl<T> PseudoElementType<T> {
     pub fn is_before(&self) -> bool {
         match *self {
             PseudoElementType::Before(_) => true,
@@ -608,6 +608,14 @@ impl PseudoElementType {
             _ => false,
         }
     }
+
+    pub fn strip(&self) -> PseudoElementType<()> {
+        match *self {
+            PseudoElementType::Normal => PseudoElementType::Normal,
+            PseudoElementType::Before(_) => PseudoElementType::Before(()),
+            PseudoElementType::After(_) => PseudoElementType::After(()),
+        }
+    }
 }
 
 /// A thread-safe version of `LayoutNode`, used during flow construction. This type of layout
@@ -617,7 +625,7 @@ pub struct ThreadSafeLayoutNode<'ln> {
     /// The wrapped node.
     node: LayoutNode<'ln>,
 
-    pseudo: PseudoElementType,
+    pseudo: PseudoElementType<display::T>,
 }
 
 impl<'ln> ThreadSafeLayoutNode<'ln> {
@@ -639,7 +647,7 @@ impl<'ln> ThreadSafeLayoutNode<'ln> {
 
     /// Creates a new `ThreadSafeLayoutNode` for the same `LayoutNode`
     /// with a different pseudo-element type.
-    fn with_pseudo(&self, pseudo: PseudoElementType) -> ThreadSafeLayoutNode<'ln> {
+    fn with_pseudo(&self, pseudo: PseudoElementType<display::T>) -> ThreadSafeLayoutNode<'ln> {
         ThreadSafeLayoutNode {
             node: self.node.clone(),
             pseudo: pseudo,
@@ -697,7 +705,7 @@ impl<'ln> ThreadSafeLayoutNode<'ln> {
     }
 
     #[inline]
-    pub fn get_pseudo_element_type(&self) -> PseudoElementType {
+    pub fn get_pseudo_element_type(&self) -> PseudoElementType<display::T> {
         self.pseudo
     }
 
diff --git a/tests/html/inline-pseudo-repair-jumpiness.html b/tests/html/inline-pseudo-repair-jumpiness.html
new file mode 100644
index 00000000000..d95c12f939c
--- /dev/null
+++ b/tests/html/inline-pseudo-repair-jumpiness.html
@@ -0,0 +1 @@
+<body>a<br>b</body>