Implement CSS text-align

src/servo/layout/box.rs

@@ -29,7 +29,7 @@ use newcss::values::{CSSBackgroundColorColor, CSSBackgroundColorTransparent, CSS
 use newcss::values::{CSSBorderWidthLength, CSSBorderWidthMedium, CSSDisplay};
 use newcss::values::{CSSFontFamilyFamilyName, CSSFontFamilyGenericFamily, CSSPositionAbsolute};
 use newcss::values::{CSSFontSizeLength, CSSFontStyleItalic, CSSFontStyleNormal};
-use newcss::values::{CSSFontStyleOblique, Specified};
+use newcss::values::{CSSFontStyleOblique, CSSTextAlign, Specified};
 use std::arc::ARC;
 use std::net::url::Url;
 
@@ -561,6 +561,13 @@ impl RenderBox : RenderBoxMethods {
             }
         }
     }
+
+    // Converts this node's ComputedStyle to a text alignment used in the inline layout code.
+    fn text_align(@self) -> CSSTextAlign {
+        do self.with_style_of_nearest_element |my_style| {
+            my_style.text_align()
+        }
+    }
 }
 
 impl RenderBox : BoxedDebugMethods {

src/servo/layout/inline.rs

@@ -13,6 +13,7 @@ use gfx::font::FontStyle;
 use gfx::geometry::Au;
 use gfx::text::util::*;
 use gfx::util::range::{MutableRange, Range};
+use newcss::values::{CSSTextAlignCenter, CSSTextAlignJustify, CSSTextAlignLeft, CSSTextAlignRight};
 use newcss::units::{BoxAuto, BoxLength, Px};
 use std::arc;
 
@@ -417,26 +418,29 @@ impl LineboxScanner {
         debug!("LineboxScanner: Setting horizontal offsets for boxes in line %u range: %?",
                self.line_spans.len(), line_range);
 
-        // TODO: use actual text align from box.style
+        // Get the text alignment.
-        enum CSSTextAlign {
+        let linebox_align;
-            AlignLeft,
+        if self.pending_line.range.begin() < self.new_boxes.len() {
-            AlignCenter,
+            let first_box = self.new_boxes[self.pending_line.range.begin()];
-            AlignRight,
+            linebox_align = first_box.text_align();
-            AlignJustify,
+        } else {
-        };
+            // Nothing to lay out, so assume left alignment.
-        let linebox_align = AlignRight;
+            // TODO: Is this a necessary check? --pcwalton
+            linebox_align = CSSTextAlignLeft;
+        }
+
         let slack_width = self.flow.d().position.size.width - self.pending_line.width;
         match linebox_align {
             // So sorry, but justified text is more complicated than shuffling linebox coordinates.
             // TODO(Issue #213): implement `text-align: justify`
-            AlignLeft | AlignJustify => {
+            CSSTextAlignLeft | CSSTextAlignJustify => {
                 for line_range.eachi |i| {
                     let box_data = &self.new_boxes[i].d();
                     box_data.position.origin.x = offset_x;
                     offset_x += box_data.position.size.width;
                 }
             },
-            AlignCenter => {
+            CSSTextAlignCenter => {
                 offset_x = slack_width.scale_by(0.5f);
                 for line_range.eachi |i| {
                     let box_data = &self.new_boxes[i].d();
@@ -444,7 +448,7 @@ impl LineboxScanner {
                     offset_x += box_data.position.size.width;
                 }
             },
-            AlignRight => {
+            CSSTextAlignRight => {
                 offset_x = slack_width;
                 for line_range.eachi |i| {
                     let box_data = &self.new_boxes[i].d();