LibWeb: Move anonymous text run filtering to Rust

Libraries/LibWeb/Layout/LayoutRustBridge.cpp

@@ -1660,23 +1660,6 @@ bool can_replay_saved_abspos_layout_inputs_after_style_change(Box const& box)
     return true;
 }
 
-static bool can_skip_is_anonymous_text_run(Box& box)
-{
-    if (box.is_anonymous() && !box.is_generated_for_pseudo_element() && !box.first_child_of_type<BlockContainer>()) {
-        bool contains_only_white_space = true;
-        box.for_each_in_subtree([&](auto const& node) {
-            if (!is<TextNode>(node) || !static_cast<TextNode const&>(node).text().is_ascii_whitespace()) {
-                contains_only_white_space = false;
-                return TraversalDecision::Break;
-            }
-            return TraversalDecision::Continue;
-        });
-        if (contains_only_white_space)
-            return true;
-    }
-    return false;
-}
-
 RustFFI::FfiLayoutFcCallbacks LayoutRustBridge::formatting_context_callbacks()
 {
     static_assert(to_underlying(Painting::Paintable::ConflictingElementKind::Cell) == 0);
@@ -2112,7 +2095,6 @@ RustFFI::FfiLayoutFcCallbacks LayoutRustBridge::formatting_context_callbacks()
                 return;
             }
             box.set_default_scroll_shift(static_cast<Box*>(anchor)->make_weak_ptr(), horizontal, vertical); },
-        .can_skip_is_anonymous_text_run = [](void*, void* box) { return can_skip_is_anonymous_text_run(*static_cast<Box*>(box)); },
     };
 }
 

Libraries/LibWeb/Layout/TextNode.cpp

@@ -411,6 +411,7 @@ void TextNode::sync_text_content_to_arena() const
         view.has_ascii_storage() ? reinterpret_cast<u8 const*>(view.ascii_span().data()) : nullptr,
         view.has_ascii_storage() ? nullptr : reinterpret_cast<u16 const*>(view.utf16_span().data()),
         view.length_in_code_units(),
+        text().is_ascii_whitespace(),
         Unicode::may_require_bidi_processing(view));
     m_arena_text_content_in_sync = true;
 }

Libraries/LibWeb/Rust/src/layout/flex_formatting_context.rs

@@ -790,10 +790,7 @@ impl<'pass> FlexFormattingContext<'pass> {
             let next = self.callbacks.next_sibling(child);
             let facts = self.facts(child);
             if facts.is_box() {
-                // SAFETY: The callback only inspects the live layout subtree.
-                let skip = unsafe {
-                    (self.callbacks.can_skip_is_anonymous_text_run)(self.callbacks.context, self.callbacks.shell(child))
-                };
+                let skip = self.callbacks.can_skip_is_anonymous_text_run(child);
                 // Skip any "out-of-flow" children
                 if !skip && !facts.is_absolutely_positioned() {
                     // Flex inhibits floating, so only absolute positioning is out of flow here.

Libraries/LibWeb/Rust/src/layout/formatting_context.rs

@@ -4891,7 +4891,6 @@ pub struct FfiLayoutFcCallbacks {
     pub anchor_function_fallback: unsafe extern "C" fn(*mut c_void, *const c_void) -> FfiAnchorFallbackFacts,
     pub set_resolved_anchor_insets: unsafe extern "C" fn(*mut c_void, *mut c_void, FfiResolvedAnchorInsets),
     pub set_default_scroll_shift: unsafe extern "C" fn(*mut c_void, *mut c_void, *mut c_void, bool, bool),
-    pub can_skip_is_anonymous_text_run: unsafe extern "C" fn(*mut c_void, *mut c_void) -> bool,
 }
 
 impl FfiLayoutFcCallbacks {
@@ -4917,6 +4916,25 @@ impl FfiLayoutFcCallbacks {
         unsafe { &*std::ptr::from_ref(content) }
     }
 
+    pub(crate) fn can_skip_is_anonymous_text_run(&self, node: Node) -> bool {
+        let data = self.node_data(node);
+        if !crate::layout::has_flag(data, NodeFlag::Anonymous) || data.generated_for != 0 {
+            return false;
+        }
+
+        let mut child = data.first_child;
+        while !child.is_invalid() {
+            let data = self.node_data(child);
+            if !crate::layout::kind_is_text(data.kind)
+                || !self.text_content(child).untransformed_text_is_ascii_whitespace
+            {
+                return false;
+            }
+            child = data.next_sibling;
+        }
+        true
+    }
+
     pub(crate) fn shell(&self, node: Node) -> *mut c_void {
         let shell = self.node_data(node).shell;
         assert!(!shell.is_null());

Libraries/LibWeb/Rust/src/layout/grid_formatting_context.rs

@@ -1858,10 +1858,7 @@ impl<'pass> GridFormattingContext<'pass> {
             let next = self.callbacks.next_sibling(child);
             let box_facts = self.facts(child);
             if box_facts.is_box() && !box_facts.is_absolutely_positioned() {
-                // SAFETY: The callback only inspects this live layout node.
-                let skip = unsafe {
-                    (self.callbacks.can_skip_is_anonymous_text_run)(self.callbacks.context, self.callbacks.shell(child))
-                };
+                let skip = self.callbacks.can_skip_is_anonymous_text_run(child);
                 if !skip {
                     self.state.set_box_is_grid_item(&self.callbacks, child, true);
                     let child_grid = self.grid_facts_copy(child);

Libraries/LibWeb/Rust/src/layout/layout_node_arena.rs

@@ -134,6 +134,7 @@ struct SavedAbsposLayoutInputsSlot {
 #[derive(Default)]
 pub(crate) struct TextContent {
     pub(crate) text: Vec<u16>,
+    pub(crate) untransformed_text_is_ascii_whitespace: bool,
     pub(crate) may_require_bidi_processing: bool,
 }
 
@@ -643,7 +644,13 @@ impl LayoutNodeArena {
         }
     }
 
-    pub(crate) fn set_text_content(&mut self, id: NodeSlotId, text: Vec<u16>, may_require_bidi_processing: bool) {
+    pub(crate) fn set_text_content(
+        &mut self,
+        id: NodeSlotId,
+        text: Vec<u16>,
+        untransformed_text_is_ascii_whitespace: bool,
+        may_require_bidi_processing: bool,
+    ) {
         self.assert_owner_thread();
         self.data(id);
         let index = id.slot_index() as usize;
@@ -654,6 +661,7 @@ impl LayoutNodeArena {
             generation: id.generation(),
             content: Some(Box::new(TextContent {
                 text,
+                untransformed_text_is_ascii_whitespace,
                 may_require_bidi_processing,
             })),
         };
@@ -813,6 +821,7 @@ pub unsafe extern "C" fn layout_arena_set_text_content(
     ascii_text: *const u8,
     utf16_text: *const u16,
     length_in_code_units: usize,
+    untransformed_text_is_ascii_whitespace: bool,
     may_require_bidi_processing: bool,
 ) {
     abort_on_panic(|| {
@@ -834,7 +843,12 @@ pub unsafe extern "C" fn layout_arena_set_text_content(
         };
         // SAFETY: The C++ wrapper keeps the arena alive for this call and
         // serializes all access on the document thread.
-        unsafe { &mut *arena.cast::<LayoutNodeArena>() }.set_text_content(id, text, may_require_bidi_processing);
+        unsafe { &mut *arena.cast::<LayoutNodeArena>() }.set_text_content(
+            id,
+            text,
+            untransformed_text_is_ascii_whitespace,
+            may_require_bidi_processing,
+        );
     });
 }