Move some of the box splitting logic into inline.rs

src/components/main/layout/box_.rs

@@ -1131,12 +1131,22 @@ impl Box {
         }
     }
 
-    /// Attempts to split this box so that its width is no more than `max_width`.
+    /// Attempts to find the split positions of a text box so that its width is
+    /// no more than `max_width`.
     ///
     /// A return value of `None` indicates that the box could not be split.
-    /// Otherwise the split boxes are returned. The left and right boxes are
+    /// Otherwise tuples of the width of the splits, the index into the text
-    /// optional due to the possibility of them being whitespace.
+    /// boxes to the left and right side of the split, and the respective text
-    pub fn split_to_width(&self, max_width: Au, starts_line: bool) -> Option<(Option<Box>, Option<Box>)> {
+    /// box info are returned. The left and right boxes are optional due to the
+    /// possibility of them being whitespace.
+    ///
+    // TODO: The returned box info values should be removed along with the box
+    // splitting logic in inline.rs
+    pub fn find_split_positions(&self, start: CharIndex, max_width: Au, starts_line: bool) -> Option<(
+        Option<(Range<CharIndex>, Au)>,
+        Option<(Range<CharIndex>, Au)>,
+        Arc<~TextRun>, // TODO: remove
+    )> {
         match self.specific {
             GenericBox | IframeBox(_) | ImageBox(_) | TableBox | TableCellBox |
             TableRowBox | TableWrapperBox => None,
@@ -1145,7 +1155,7 @@ impl Box {
             ScannedTextBox(ref text_box_info) => {
                 let mut pieces_processed_count: uint = 0;
                 let mut remaining_width: Au = max_width;
-                let mut left_range = Range::new(text_box_info.range.begin(), CharIndex(0));
+                let mut left_range = Range::new(text_box_info.range.begin() + start, CharIndex(0));
                 let mut right_range: Option<Range<CharIndex>> = None;
 
                 debug!("split_to_width: splitting text box (strlen={:u}, range={}, \
@@ -1217,25 +1227,17 @@ impl Box {
                 if (pieces_processed_count == 1 || !left_is_some) && !starts_line {
                     None
                 } else {
-                    let left_box = if left_is_some {
+                    let left = if left_is_some {
-                        let new_text_box_info = ScannedTextBoxInfo::new(text_box_info.run.clone(), left_range);
+                        Some((left_range, text_box_info.run.advance_for_range(&left_range)))
-                        let width = new_text_box_info.run.advance_for_range(&left_range);
-                        let height = self.border_box.size.height;
-                        let size = Size2D(width, height);
-                        Some(self.transform(size, ScannedTextBox(new_text_box_info)))
                     } else {
                         None
                     };
 
-                    let right_box = right_range.map(|right_range| {
+                    let right = right_range.map(|right_range| {
-                        let new_text_box_info = ScannedTextBoxInfo::new(text_box_info.run.clone(), right_range);
+                        (right_range, text_box_info.run.advance_for_range(&right_range))
-                        let width = new_text_box_info.run.advance_for_range(&right_range);
-                        let height = self.border_box.size.height;
-                        let size = Size2D(width, height);
-                        (self.transform(size, ScannedTextBox(new_text_box_info)))
                     });
 
-                    Some((left_box, right_box))
+                    Some((left, right, text_box_info.run.clone()))
                 }
             }
         }

src/components/main/layout/inline.rs

@@ -3,7 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use css::node_style::StyledNode;
-use layout::box_::Box;
+use layout::box_::{Box, ScannedTextBox, ScannedTextBoxInfo};
 use layout::context::LayoutContext;
 use layout::floats::{FloatLeft, Floats, PlacementInfo};
 use layout::flow::{BaseFlow, FlowClass, Flow, InlineFlowClass};
@@ -492,7 +492,20 @@ impl LineboxScanner {
         }
 
         let available_width = green_zone.width - self.pending_line.bounds.size.width;
-        match in_box.split_to_width(available_width, line_is_empty) {
+        match in_box.find_split_positions(CharIndex(0), available_width, line_is_empty).map(
+            |(left, right, run)| {
+                let make_box = |(range, width): (Range<CharIndex>, Au)| {
+                    let info = ScannedTextBoxInfo::new(run.clone(), range);
+                    let specific = ScannedTextBox(info);
+                    let size = Size2D(width, in_box.border_box.size.height);
+                    // TODO: Remove box splitting
+                    in_box.transform(size, specific)
+                };
+
+                (left.map(|x|  { debug!("LineboxScanner: Left split {}",  x); make_box(x) }),
+                 right.map(|x| { debug!("LineboxScanner: Right split {}", x); make_box(x) }))
+            }
+        ) {
             None => {
                 debug!("LineboxScanner: Tried to split unsplittable render box! Deferring to next \
                        line. {}", in_box);