Break text runs by unicode script

components/gfx/Cargo.toml

@@ -23,6 +23,7 @@ serde_macros = "0.5"
 smallvec = "0.1"
 string_cache = "0.1"
 time = "0.1.12"
+unicode-script = { version = "0.1", features = ["harfbuzz"] }
 
 [dependencies.plugins]
 path = "../plugins"

components/gfx/font.rs

@@ -18,6 +18,7 @@ use style::properties::style_structs::Font as FontStyle;
 use text::Shaper;
 use text::glyph::{GlyphId, GlyphStore};
 use text::shaping::ShaperMethods;
+use unicode_script::Script;
 use util::cache::HashCache;
 use util::geometry::Au;
 
@@ -117,6 +118,8 @@ pub struct ShapingOptions {
     pub letter_spacing: Option<Au>,
     /// Spacing to add between each word. Corresponds to the CSS 2.1 `word-spacing` property.
     pub word_spacing: Au,
+    /// The Unicode script property of the characters in this run.
+    pub script: Script,
     /// Various flags.
     pub flags: ShapingFlags,
 }

components/gfx/lib.rs

@@ -72,6 +72,7 @@ extern crate smallvec;
 extern crate string_cache;
 extern crate style;
 extern crate time;
+extern crate unicode_script;
 extern crate url;
 
 

components/gfx/text/shaping/harfbuzz.rs

@@ -215,6 +215,8 @@ impl ShaperMethods for Shaper {
                 HB_DIRECTION_LTR
             });
 
+            hb_buffer_set_script(hb_buffer, options.script.to_hb_script());
+
             hb_buffer_add_utf8(hb_buffer,
                                text.as_ptr() as *const c_char,
                                text.len() as c_int,