Use word-break to decide how glyph runs should be created

4 files changed, 15 insertions, 72 deletions

diff --git a/components/gfx/font.rs b/components/gfx/font.rs
index 7e1cf5236d5..c955c042eff 100644
--- a/components/gfx/font.rs
+++ b/components/gfx/font.rs
@@ -148,6 +148,8 @@ bitflags! {
         const DISABLE_KERNING_SHAPING_FLAG = 0x04,
         #[doc = "Text direction is right-to-left."]
         const RTL_FLAG = 0x08,
+        #[doc = "Set if word-break is set to keep-all."]
+        const KEEP_ALL_FLAG = 0x10,
     }
 }
 
diff --git a/components/gfx/text/text_run.rs b/components/gfx/text/text_run.rs
index 9455c862aeb..7ab8f4a870f 100644
--- a/components/gfx/text/text_run.rs
+++ b/components/gfx/text/text_run.rs
@@ -3,8 +3,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use app_units::Au;
-use font::{Font, FontHandleMethods, FontMetrics, IS_WHITESPACE_SHAPING_FLAG, RunMetrics};
-use font::ShapingOptions;
+use font::{Font, FontHandleMethods, FontMetrics, IS_WHITESPACE_SHAPING_FLAG, KEEP_ALL_FLAG};
+use font::{RunMetrics, ShapingOptions};
 use platform::font_template::FontTemplateData;
 use range::Range;
 use std::cell::Cell;
@@ -135,53 +135,6 @@ impl<'a> Iterator for NaturalWordSliceIterator<'a> {
     }
 }
 
-pub struct SoftWrapSliceIterator<'a> {
-    text: &'a str,
-    glyph_run: Option<&'a GlyphRun>,
-    glyph_run_iter: Iter<'a, GlyphRun>,
-    range: Range<ByteIndex>,
-}
-
-// This is like NaturalWordSliceIterator, except that soft-wrap opportunities
-// are allowed. That is, word boundaries are defined solely by UAX#29,
-// regardless of whether the sequence being broken into different slices is
-// a sequence of alphanumeric characters. This shouldn't make a difference in
-// the case of Latin text, but it does in ideographic characters, as well as
-// scripts such as Thai.
-impl<'a> Iterator for SoftWrapSliceIterator<'a> {
-    type Item = TextRunSlice<'a>;
-
-    #[inline(always)]
-    fn next(&mut self) -> Option<TextRunSlice<'a>> {
-        let glyph_run = match self.glyph_run {
-            None => return None,
-            Some(glyph_run) => glyph_run,
-        };
-
-        let text_start = self.range.begin();
-        let text = &self.text[text_start.to_usize()..glyph_run.range.end().to_usize()];
-        let slice_text = match LineBreakIterator::new(text).next() {
-            Some((idx, _)) => &text[0..idx],
-            None => unreachable!()
-        };
-
-        let slice_len = ByteIndex(slice_text.len() as isize);
-        self.range.adjust_by(slice_len, -slice_len);
-        if self.range.is_empty() {
-            self.glyph_run = None
-        } else if self.range.intersect(&glyph_run.range).is_empty() {
-            self.glyph_run = self.glyph_run_iter.next();
-        }
-
-        let index_within_glyph_run = text_start - glyph_run.range.begin();
-        Some(TextRunSlice {
-            glyphs: &*glyph_run.glyph_store,
-            offset: glyph_run.range.begin(),
-            range: Range::new(index_within_glyph_run, slice_len),
-        })
-    }
-}
-
 pub struct CharacterSliceIterator<'a> {
     text: &'a str,
     glyph_run: Option<&'a GlyphRun>,
@@ -256,8 +209,9 @@ impl<'a> TextRun {
                 .take_while(|&(_, c)| char_is_whitespace(c)).last() {
                     whitespace.start = slice.start + i;
                     slice.end = whitespace.start;
-                } else if idx != text.len() {
-                    // If there's no whitespace, try increasing the slice.
+                } else if idx != text.len() && options.flags.contains(KEEP_ALL_FLAG) {
+                    // If there's no whitespace and word-break is set to
+                    // keep-all, try increasing the slice.
                     continue;
                 }
             if slice.len() > 0 {
@@ -392,24 +346,6 @@ impl<'a> TextRun {
         }
     }
 
-    /// Returns an iterator that will iterate over all slices of glyphs that represent natural
-    /// words in the given range, where soft wrap opportunities are taken into account.
-    pub fn soft_wrap_slices_in_range(&'a self, range: &Range<ByteIndex>)
-                                        -> SoftWrapSliceIterator<'a> {
-        let index = match self.index_of_first_glyph_run_containing(range.begin()) {
-            None => self.glyphs.len(),
-            Some(index) => index,
-        };
-        let mut glyph_run_iter = self.glyphs[index..].iter();
-        let first_glyph_run = glyph_run_iter.next();
-        SoftWrapSliceIterator {
-            text: &self.text,
-            glyph_run: first_glyph_run,
-            glyph_run_iter: glyph_run_iter,
-            range: *range,
-        }
-    }
-
     /// Returns an iterator that will iterate over all slices of glyphs that represent individual
     /// characters in the given range.
     pub fn character_slices_in_range(&'a self, range: &Range<ByteIndex>)
diff --git a/components/layout/fragment.rs b/components/layout/fragment.rs
index 93a19f14af1..2dc8db47f60 100644
--- a/components/layout/fragment.rs
+++ b/components/layout/fragment.rs
@@ -1640,7 +1640,7 @@ impl Fragment {
             word_break::T::normal => {
                 // Break at normal word boundaries, allowing for soft wrap opportunities.
                 let soft_wrap_breaking_strategy =
-                    text_fragment_info.run.soft_wrap_slices_in_range(&text_fragment_info.range);
+                    text_fragment_info.run.natural_word_slices_in_range(&text_fragment_info.range);
                 self.calculate_split_position_using_breaking_strategy(
                     soft_wrap_breaking_strategy,
                     max_inline_size,
diff --git a/components/layout/text.rs b/components/layout/text.rs
index 18d2cbf3c08..237f339ea71 100644
--- a/components/layout/text.rs
+++ b/components/layout/text.rs
@@ -10,7 +10,7 @@ use app_units::Au;
 use fragment::{Fragment, REQUIRES_LINE_BREAK_AFTERWARD_IF_WRAPPING_ON_NEWLINES, ScannedTextFlags};
 use fragment::{SELECTED, ScannedTextFragmentInfo, SpecificFragmentInfo, UnscannedTextFragmentInfo};
 use gfx::font::{DISABLE_KERNING_SHAPING_FLAG, FontMetrics, IGNORE_LIGATURES_SHAPING_FLAG};
-use gfx::font::{RTL_FLAG, RunMetrics, ShapingFlags, ShapingOptions};
+use gfx::font::{KEEP_ALL_FLAG, RTL_FLAG, RunMetrics, ShapingFlags, ShapingOptions};
 use gfx::font_context::FontContext;
 use gfx::text::glyph::ByteIndex;
 use gfx::text::text_run::TextRun;
@@ -24,7 +24,7 @@ use std::collections::LinkedList;
 use std::mem;
 use std::sync::Arc;
 use style::computed_values::{line_height, text_orientation, text_rendering, text_transform};
-use style::computed_values::white_space;
+use style::computed_values::{word_break, white_space};
 use style::logical_geometry::{LogicalSize, WritingMode};
 use style::properties::ServoComputedValues;
 use style::properties::style_structs;
@@ -151,6 +151,7 @@ impl TextRunScanner {
             let letter_spacing;
             let word_spacing;
             let text_rendering;
+            let word_break;
             {
                 let in_fragment = self.clump.front().unwrap();
                 let font_style = in_fragment.style().get_font_arc();
@@ -169,6 +170,7 @@ impl TextRunScanner {
                                .map(|lop| lop.to_hash_key())
                                .unwrap_or((Au(0), NotNaN::new(0.0).unwrap()));
                 text_rendering = inherited_text_style.text_rendering;
+                word_break = inherited_text_style.word_break;
             }
 
             // First, transform/compress text of all the nodes.
@@ -289,6 +291,9 @@ impl TextRunScanner {
                 flags.insert(IGNORE_LIGATURES_SHAPING_FLAG);
                 flags.insert(DISABLE_KERNING_SHAPING_FLAG)
             }
+            if word_break == word_break::T::keep_all {
+                flags.insert(KEEP_ALL_FLAG);
+            }
             let options = ShapingOptions {
                 letter_spacing: letter_spacing,
                 word_spacing: word_spacing,