Implement the correct ToCss for UrlSource.

1 files changed, 19 insertions, 2 deletions

diff --git a/components/style/font_face.rs b/components/style/font_face.rs
index 7e4b45c2482..31ba80faddc 100644
--- a/components/style/font_face.rs
+++ b/components/style/font_face.rs
@@ -24,6 +24,7 @@ use std::fmt::{self, Write};
 use str::CssStringWriter;
 use style_traits::{Comma, CssWriter, OneOrMoreSeparated, ParseError};
 use style_traits::{StyleParseErrorKind, ToCss};
+use style_traits::values::SequenceWriter;
 use values::computed::font::FamilyName;
 #[cfg(feature = "gecko")]
 use values::specified::font::{SpecifiedFontFeatureSettings, SpecifiedFontVariationSettings};
@@ -49,15 +50,31 @@ impl OneOrMoreSeparated for Source {
 ///
 /// <https://drafts.csswg.org/css-fonts/#src-desc>
 #[cfg_attr(feature = "servo", derive(Deserialize, Serialize))]
-#[derive(Clone, Debug, Eq, PartialEq, ToCss)]
+#[derive(Clone, Debug, Eq, PartialEq)]
 pub struct UrlSource {
     /// The specified url.
     pub url: SpecifiedUrl,
     /// The format hints specified with the `format()` function.
-    #[css(skip)]
     pub format_hints: Vec<String>,
 }
 
+impl ToCss for UrlSource {
+    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
+        self.url.to_css(dest)?;
+        if !self.format_hints.is_empty() {
+            dest.write_str(" format(")?;
+            {
+                let mut writer = SequenceWriter::new(dest, ", ");
+                for hint in self.format_hints.iter() {
+                    writer.item(hint)?;
+                }
+            }
+            dest.write_char(')')?;
+        }
+        Ok(())
+    }
+}
+
 /// A font-display value for a @font-face rule.
 /// The font-display descriptor determines how a font face is displayed based
 /// on whether and when it is downloaded and ready to use.