Auto merge of #17215 - servo:derive-all-the-things, r=emilio

Derive more ToCss impls

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15 files changed, 54 insertions, 96 deletions

diff --git a/components/layout/display_list_builder.rs b/components/layout/display_list_builder.rs
index 4a7f2814cbf..b97aeb4c1fa 100644
--- a/components/layout/display_list_builder.rs
+++ b/components/layout/display_list_builder.rs
@@ -2853,8 +2853,8 @@ impl ServoComputedValuesCursorUtility for ServoComputedValues {
     fn get_cursor(&self, default_cursor: Cursor) -> Option<Cursor> {
         match (self.get_pointing().pointer_events, self.get_pointing().cursor) {
             (pointer_events::T::none, _) => None,
-            (pointer_events::T::auto, cursor::Keyword::AutoCursor) => Some(default_cursor),
-            (pointer_events::T::auto, cursor::Keyword::SpecifiedCursor(cursor)) => Some(cursor),
+            (pointer_events::T::auto, cursor::Keyword::Auto) => Some(default_cursor),
+            (pointer_events::T::auto, cursor::Keyword::Cursor(cursor)) => Some(cursor),
         }
     }
 }
diff --git a/components/style/counter_style/mod.rs b/components/style/counter_style/mod.rs
index a018f9b8286..55d1010259c 100644
--- a/components/style/counter_style/mod.rs
+++ b/components/style/counter_style/mod.rs
@@ -7,8 +7,8 @@
 //! [counter-style]: https://drafts.csswg.org/css-counter-styles/
 
 use Atom;
-use cssparser::{AtRuleParser, DeclarationListParser, DeclarationParser, Parser, Token};
-use cssparser::{serialize_string, serialize_identifier};
+use cssparser::{AtRuleParser, DeclarationListParser, DeclarationParser};
+use cssparser::{Parser, Token, serialize_identifier};
 #[cfg(feature = "gecko")] use gecko::rules::CounterStyleDescriptors;
 #[cfg(feature = "gecko")] use gecko_bindings::structs::nsCSSCounterDesc;
 use parser::{ParserContext, log_css_error, Parse};
@@ -361,7 +361,7 @@ impl Parse for Symbol {
 impl ToCss for Symbol {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
         match *self {
-            Symbol::String(ref s) => serialize_string(s, dest),
+            Symbol::String(ref s) => s.to_css(dest),
             Symbol::Ident(ref s) => serialize_identifier(s, dest),
         }
     }
diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 3905400ce8d..5b87bdc853d 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -4241,8 +4241,8 @@ clip-path
         use style_traits::cursor::Cursor;
 
         self.gecko.mCursor = match v.keyword {
-            Keyword::AutoCursor => structs::NS_STYLE_CURSOR_AUTO,
-            Keyword::SpecifiedCursor(cursor) => match cursor {
+            Keyword::Auto => structs::NS_STYLE_CURSOR_AUTO,
+            Keyword::Cursor(cursor) => match cursor {
                 Cursor::None => structs::NS_STYLE_CURSOR_NONE,
                 Cursor::Default => structs::NS_STYLE_CURSOR_DEFAULT,
                 Cursor::Pointer => structs::NS_STYLE_CURSOR_POINTER,
diff --git a/components/style/properties/longhand/counters.mako.rs b/components/style/properties/longhand/counters.mako.rs
index e71d80c42af..55d054e8a27 100644
--- a/components/style/properties/longhand/counters.mako.rs
+++ b/components/style/properties/longhand/counters.mako.rs
@@ -70,9 +70,7 @@
         impl ToCss for ContentItem {
             fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
                 match *self {
-                    ContentItem::String(ref s) => {
-                        cssparser::serialize_string(&**s, dest)
-                    }
+                    ContentItem::String(ref s) => s.to_css(dest),
                     ContentItem::Counter(ref s, ref counter_style) => {
                         try!(dest.write_str("counter("));
                         try!(cssparser::serialize_identifier(&**s, dest));
@@ -84,9 +82,9 @@
                         try!(dest.write_str("counters("));
                         try!(cssparser::serialize_identifier(&**s, dest));
                         try!(dest.write_str(", "));
-                        try!(cssparser::serialize_string(&**separator, dest));
+                        separator.to_css(dest)?;
                         try!(dest.write_str(", "));
-                        try!(counter_style.to_css(dest));
+                        counter_style.to_css(dest)?;
                         dest.write_str(")")
                     }
                     ContentItem::OpenQuote => dest.write_str("open-quote"),
diff --git a/components/style/properties/longhand/font.mako.rs b/components/style/properties/longhand/font.mako.rs
index 825577b1e60..127a1856e3e 100644
--- a/components/style/properties/longhand/font.mako.rs
+++ b/components/style/properties/longhand/font.mako.rs
@@ -1894,11 +1894,9 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
 
     impl ToCss for SpecifiedValue {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            use cssparser;
             match *self {
                 SpecifiedValue::Normal => dest.write_str("normal"),
-                SpecifiedValue::Override(ref lang) =>
-                    cssparser::serialize_string(lang, dest),
+                SpecifiedValue::Override(ref lang) => lang.to_css(dest),
                 SpecifiedValue::System(_) => Ok(())
             }
         }
@@ -1921,7 +1919,6 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
         use std::{fmt, str};
         use style_traits::ToCss;
         use byteorder::{BigEndian, ByteOrder};
-        use cssparser;
 
         impl ToCss for T {
             fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
@@ -1936,7 +1933,7 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
                 } else {
                     unsafe { str::from_utf8_unchecked(&buf) }
                 };
-                cssparser::serialize_string(slice.trim_right(), dest)
+                slice.trim_right().to_css(dest)
             }
         }
 
diff --git a/components/style/properties/longhand/inherited_text.mako.rs b/components/style/properties/longhand/inherited_text.mako.rs
index f78059017b5..c5301e31378 100644
--- a/components/style/properties/longhand/inherited_text.mako.rs
+++ b/components/style/properties/longhand/inherited_text.mako.rs
@@ -427,8 +427,8 @@ ${helpers.predefined_type("word-spacing",
     no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
-        #[derive(Debug, Clone, PartialEq)]
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
+        #[derive(Clone, Debug, PartialEq, ToCss)]
         pub enum T {
             Keyword(KeywordValue),
             None,
@@ -443,33 +443,14 @@ ${helpers.predefined_type("word-spacing",
         }
     }
 
-    #[derive(Debug, Clone, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
+    #[derive(Clone, Debug, PartialEq, ToCss)]
     pub enum SpecifiedValue {
         Keyword(KeywordValue),
         None,
         String(String),
     }
 
-    impl ToCss for computed_value::T {
-        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            match *self {
-                computed_value::T::Keyword(ref keyword) => keyword.to_css(dest),
-                computed_value::T::None => dest.write_str("none"),
-                computed_value::T::String(ref string) => write!(dest, "\"{}\"", string),
-            }
-        }
-    }
-    impl ToCss for SpecifiedValue {
-        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            match *self {
-                SpecifiedValue::Keyword(ref keyword) => keyword.to_css(dest),
-                SpecifiedValue::None => dest.write_str("none"),
-                SpecifiedValue::String(ref string) => write!(dest, "\"{}\"", string),
-            }
-        }
-    }
-
     #[derive(Debug, Clone, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     pub enum KeywordValue {
diff --git a/components/style/properties/longhand/list.mako.rs b/components/style/properties/longhand/list.mako.rs
index 620695f3eba..649b04c3eaf 100644
--- a/components/style/properties/longhand/list.mako.rs
+++ b/components/style/properties/longhand/list.mako.rs
@@ -33,9 +33,6 @@ ${helpers.single_keyword("list-style-position", "outside inside", animation_valu
 % else:
     <%helpers:longhand name="list-style-type" animation_value_type="none" boxed="True"
                        spec="https://drafts.csswg.org/css-lists/#propdef-list-style-type">
-        use cssparser;
-        use std::fmt;
-        use style_traits::ToCss;
         use values::CustomIdent;
         use values::computed::ComputedValueAsSpecified;
         use values::generics::CounterStyleOrNone;
@@ -46,7 +43,7 @@ ${helpers.single_keyword("list-style-position", "outside inside", animation_valu
             use values::generics::CounterStyleOrNone;
 
             /// <counter-style> | <string> | none
-            #[derive(Debug, Clone, PartialEq, Eq)]
+            #[derive(Debug, Clone, Eq, PartialEq, ToCss)]
             pub enum T {
                 CounterStyle(CounterStyleOrNone),
                 String(String),
@@ -56,15 +53,6 @@ ${helpers.single_keyword("list-style-position", "outside inside", animation_valu
         impl ComputedValueAsSpecified for SpecifiedValue {}
         no_viewport_percentage!(SpecifiedValue);
 
-        impl ToCss for SpecifiedValue {
-            fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-                match *self {
-                    SpecifiedValue::CounterStyle(ref s) => s.to_css(dest),
-                    SpecifiedValue::String(ref s) => cssparser::serialize_string(s, dest)
-                }
-            }
-        }
-
         #[cfg(feature = "gecko")]
         impl SpecifiedValue {
             /// Convert from gecko keyword to list-style-type.
diff --git a/components/style/properties/longhand/pointing.mako.rs b/components/style/properties/longhand/pointing.mako.rs
index bba9b160638..05f014a07da 100644
--- a/components/style/properties/longhand/pointing.mako.rs
+++ b/components/style/properties/longhand/pointing.mako.rs
@@ -17,17 +17,19 @@
     no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
+        #[cfg(feature = "gecko")]
         use std::fmt;
-        use style_traits::cursor::Cursor;
+        #[cfg(feature = "gecko")]
         use style_traits::ToCss;
+        use style_traits::cursor::Cursor;
         #[cfg(feature = "gecko")]
         use values::specified::url::SpecifiedUrl;
 
-        #[derive(Clone, PartialEq, Copy, Debug)]
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
+        #[derive(Clone, Copy, Debug, PartialEq, ToCss)]
         pub enum Keyword {
-            AutoCursor,
-            SpecifiedCursor(Cursor),
+            Auto,
+            Cursor(Cursor),
         }
 
         #[cfg(not(feature = "gecko"))]
@@ -47,15 +49,6 @@
             pub keyword: Keyword,
         }
 
-        impl ToCss for Keyword {
-            fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-                match *self {
-                    Keyword::AutoCursor => dest.write_str("auto"),
-                    Keyword::SpecifiedCursor(c) => c.to_css(dest),
-                }
-            }
-        }
-
         #[cfg(feature = "gecko")]
         impl ToCss for Image {
             fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
@@ -85,7 +78,7 @@
     #[cfg(not(feature = "gecko"))]
     #[inline]
     pub fn get_initial_value() -> computed_value::T {
-        computed_value::Keyword::AutoCursor
+        computed_value::Keyword::Auto
     }
 
     #[cfg(feature = "gecko")]
@@ -93,7 +86,7 @@
     pub fn get_initial_value() -> computed_value::T {
         computed_value::T {
             images: vec![],
-            keyword: computed_value::Keyword::AutoCursor
+            keyword: computed_value::Keyword::Auto
         }
     }
 
@@ -103,9 +96,9 @@
             use style_traits::cursor::Cursor;
             let ident = try!(input.expect_ident());
             if ident.eq_ignore_ascii_case("auto") {
-                Ok(computed_value::Keyword::AutoCursor)
+                Ok(computed_value::Keyword::Auto)
             } else {
-                Cursor::from_css_keyword(&ident).map(computed_value::Keyword::SpecifiedCursor)
+                Cursor::from_css_keyword(&ident).map(computed_value::Keyword::Cursor)
             }
         }
     }
diff --git a/components/style/properties/longhand/position.mako.rs b/components/style/properties/longhand/position.mako.rs
index ebf4265cd0d..748f8a4ae81 100644
--- a/components/style/properties/longhand/position.mako.rs
+++ b/components/style/properties/longhand/position.mako.rs
@@ -354,7 +354,6 @@ ${helpers.predefined_type("object-position",
         animation_value_type="none"
         disable_when_testing="True"
         boxed="True">
-    use cssparser::serialize_string;
     use std::collections::HashMap;
     use std::fmt;
     use std::ops::Range;
@@ -486,7 +485,7 @@ ${helpers.predefined_type("object-position",
                 if i != 0 {
                     dest.write_str(" ")?;
                 }
-                serialize_string(string, dest)?;
+                string.to_css(dest)?;
             }
             Ok(())
         }
diff --git a/components/style/properties/longhand/text.mako.rs b/components/style/properties/longhand/text.mako.rs
index 08113b228f2..6ebf1e9d277 100644
--- a/components/style/properties/longhand/text.mako.rs
+++ b/components/style/properties/longhand/text.mako.rs
@@ -16,12 +16,11 @@
                    spec="https://drafts.csswg.org/css-ui/#propdef-text-overflow">
     use std::fmt;
     use style_traits::ToCss;
-    use cssparser;
 
     no_viewport_percentage!(SpecifiedValue);
 
-    #[derive(PartialEq, Eq, Clone, Debug)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
+    #[derive(Clone, Debug, Eq, PartialEq, ToCss)]
     pub enum Side {
         Clip,
         Ellipsis,
@@ -127,18 +126,6 @@
         }
     }
 
-    impl ToCss for Side {
-        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            match *self {
-                Side::Clip => dest.write_str("clip"),
-                Side::Ellipsis => dest.write_str("ellipsis"),
-                Side::String(ref s) => {
-                    cssparser::serialize_string(s, dest)
-                }
-            }
-        }
-    }
-
     impl ToCss for SpecifiedValue {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
             try!(self.first.to_css(dest));
diff --git a/components/style/properties/shorthand/position.mako.rs b/components/style/properties/shorthand/position.mako.rs
index 65586ab1ec2..6627edd92bf 100644
--- a/components/style/properties/shorthand/position.mako.rs
+++ b/components/style/properties/shorthand/position.mako.rs
@@ -250,7 +250,6 @@
                     spec="https://drafts.csswg.org/css-grid/#propdef-grid-template"
                     disable_when_testing="True"
                     products="gecko">
-    use cssparser::serialize_string;
     use parser::Parse;
     use properties::longhands::grid_template_rows;
     use properties::longhands::grid_template_areas::TemplateAreas;
@@ -370,7 +369,7 @@
                         concat_serialize_idents("[", "] ", names, " ", dest)?;
                     }
 
-                    serialize_string(string, dest)?;
+                    string.to_css(dest)?;
                     dest.write_str(" ")?;
                     size.to_css(dest)?;
                 }
diff --git a/components/style/stylesheets/document_rule.rs b/components/style/stylesheets/document_rule.rs
index 0c79b0bfd8e..f921eeb7631 100644
--- a/components/style/stylesheets/document_rule.rs
+++ b/components/style/stylesheets/document_rule.rs
@@ -6,7 +6,7 @@
 //! initially in CSS Conditional Rules Module Level 3, @document has been postponed to the level 4.
 //! We implement the prefixed `@-moz-document`.
 
-use cssparser::{Parser, Token, SourceLocation, serialize_string};
+use cssparser::{Parser, Token, SourceLocation};
 use media_queries::Device;
 use parser::{Parse, ParserContext};
 use shared_lock::{DeepCloneWithLock, Locked, SharedRwLock, SharedRwLockReadGuard, ToCssWithGuard};
@@ -160,17 +160,17 @@ impl ToCss for UrlMatchingFunction {
             },
             UrlMatchingFunction::UrlPrefix(ref url_prefix) => {
                 dest.write_str("url-prefix(")?;
-                serialize_string(url_prefix, dest)?;
+                url_prefix.to_css(dest)?;
                 dest.write_str(")")
             },
             UrlMatchingFunction::Domain(ref domain) => {
                 dest.write_str("domain(")?;
-                serialize_string(domain, dest)?;
+                domain.to_css(dest)?;
                 dest.write_str(")")
             },
             UrlMatchingFunction::RegExp(ref regex) => {
                 dest.write_str("regexp(")?;
-                serialize_string(regex, dest)?;
+                regex.to_css(dest)?;
                 dest.write_str(")")
             },
         }
diff --git a/components/style/values/generics/mod.rs b/components/style/values/generics/mod.rs
index 40d3f4e46df..da0ba4a4301 100644
--- a/components/style/values/generics/mod.rs
+++ b/components/style/values/generics/mod.rs
@@ -143,12 +143,11 @@ impl<T> OneOrMoreCommaSeparated for FontSettingTag<T> {}
 impl<T: ToCss> ToCss for FontSettingTag<T> {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
         use byteorder::{BigEndian, ByteOrder};
-        use cssparser::serialize_string;
         use std::str;
 
         let mut raw = [0u8; 4];
         BigEndian::write_u32(&mut raw, self.tag);
-        serialize_string(str::from_utf8(&raw).unwrap_or_default(), dest)?;
+        str::from_utf8(&raw).unwrap_or_default().to_css(dest)?;
 
         self.value.to_css(dest)
     }
diff --git a/components/style/values/mod.rs b/components/style/values/mod.rs
index 506584c1e76..32b7df063c9 100644
--- a/components/style/values/mod.rs
+++ b/components/style/values/mod.rs
@@ -9,7 +9,7 @@
 #![deny(missing_docs)]
 
 use Atom;
-pub use cssparser::{RGBA, Token, Parser, serialize_identifier, serialize_string};
+pub use cssparser::{RGBA, Token, Parser, serialize_identifier};
 use parser::{Parse, ParserContext};
 use std::ascii::AsciiExt;
 use std::borrow::Cow;
@@ -166,7 +166,7 @@ impl ToCss for KeyframesName {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
         match *self {
             KeyframesName::Ident(ref ident) => ident.to_css(dest),
-            KeyframesName::QuotedString(ref atom) => serialize_string(&atom.to_string(), dest),
+            KeyframesName::QuotedString(ref atom) => atom.to_string().to_css(dest),
         }
     }
 }
diff --git a/components/style_traits/values.rs b/components/style_traits/values.rs
index 7c73f7bd4cf..406df824e37 100644
--- a/components/style_traits/values.rs
+++ b/components/style_traits/values.rs
@@ -5,11 +5,14 @@
 //! Helper types and traits for the handling of CSS values.
 
 use app_units::Au;
-use cssparser::UnicodeRange;
+use cssparser::{UnicodeRange, serialize_string};
 use std::fmt;
 
 /// Serialises a value according to its CSS representation.
 ///
+/// This trait is implemented for `str` and its friends, serialising the string
+/// contents as a CSS quoted string.
+///
 /// This trait is derivable with `#[derive(ToCss)]`, with the following behaviour:
 /// * unit variants get serialised as the `snake-case` representation
 ///   of their name;
@@ -38,6 +41,20 @@ impl<'a, T> ToCss for &'a T where T: ToCss + ?Sized {
     }
 }
 
+impl ToCss for str {
+    #[inline]
+    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+        serialize_string(self, dest)
+    }
+}
+
+impl ToCss for String {
+    #[inline]
+    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+        serialize_string(self, dest)
+    }
+}
+
 /// Marker trait to automatically implement ToCss for Vec<T>.
 pub trait OneOrMoreCommaSeparated {}
 
@@ -55,7 +72,7 @@ impl<T> ToCss for Vec<T> where T: ToCss + OneOrMoreCommaSeparated {
     }
 }
 
-impl<T: ToCss> ToCss for Box<T> {
+impl<T> ToCss for Box<T> where T: ?Sized + ToCss {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result
         where W: fmt::Write,
     {