Auto merge of #20196 - servo:derive-all-the-things, r=emilio

Derive some more ToCss implementations

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components/style/counter_style/mod.rs

@@ -444,7 +444,18 @@ impl Parse for Negative {
 ///
 /// Empty Vec represents 'auto'
 #[derive(Clone, Debug)]
-pub struct Ranges(pub Vec<Range<Option<i32>>>);
+pub struct Ranges(pub Vec<Range<CounterBound>>);
+
+/// A bound found in `Ranges`.
+#[derive(Clone, Copy, Debug, ToCss)]
+pub enum CounterBound {
+    /// An integer bound.
+    ///
+    /// FIXME(https://github.com/servo/servo/issues/20197)
+    Integer(i32),
+    /// The infinite bound.
+    Infinite,
+}
 
 impl Parse for Ranges {
     fn parse<'i, 't>(_context: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
@@ -454,7 +465,7 @@ impl Parse for Ranges {
             input.parse_comma_separated(|input| {
                 let opt_start = parse_bound(input)?;
                 let opt_end = parse_bound(input)?;
-                if let (Some(start), Some(end)) = (opt_start, opt_end) {
+                if let (CounterBound::Integer(start), CounterBound::Integer(end)) = (opt_start, opt_end) {
                     if start > end {
                         return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
                     }
@@ -465,11 +476,17 @@ impl Parse for Ranges {
     }
 }
 
-fn parse_bound<'i, 't>(input: &mut Parser<'i, 't>) -> Result<Option<i32>, ParseError<'i>> {
+fn parse_bound<'i, 't>(
+    input: &mut Parser<'i, 't>,
+) -> Result<CounterBound, ParseError<'i>> {
     let location = input.current_source_location();
     match *input.next()? {
-        Token::Number { int_value: Some(v), .. } => Ok(Some(v)),
+        Token::Number { int_value: Some(v), .. } => {
-        Token::Ident(ref ident) if ident.eq_ignore_ascii_case("infinite") => Ok(None),
+            Ok(CounterBound::Integer(v))
+        }
+        Token::Ident(ref ident) if ident.eq_ignore_ascii_case("infinite") => {
+            Ok(CounterBound::Infinite)
+        }
         ref t => Err(location.new_unexpected_token_error(t.clone())),
     }
 }
@@ -493,24 +510,13 @@ impl ToCss for Ranges {
     }
 }
 
-fn range_to_css<W>(range: &Range<Option<i32>>, dest: &mut CssWriter<W>) -> fmt::Result
+fn range_to_css<W>(range: &Range<CounterBound>, dest: &mut CssWriter<W>) -> fmt::Result
 where
     W: Write,
 {
-    bound_to_css(range.start, dest)?;
+    range.start.to_css(dest)?;
     dest.write_char(' ')?;
-    bound_to_css(range.end, dest)
+    range.end.to_css(dest)
-}
-
-fn bound_to_css<W>(range: Option<i32>, dest: &mut CssWriter<W>) -> fmt::Result
-where
-    W: Write,
-{
-    if let Some(finite) = range {
-        finite.to_css(dest)
-    } else {
-        dest.write_str("infinite")
-    }
 }
 
 /// <https://drafts.csswg.org/css-counter-styles/#counter-style-pad>

components/style/gecko/rules.rs

@@ -6,7 +6,7 @@
 
 use byteorder::{BigEndian, WriteBytesExt};
 use computed_values::{font_stretch, font_style, font_weight};
-use counter_style;
+use counter_style::{self, CounterBound};
 use cssparser::UnicodeRange;
 use font_face::{FontFaceRuleData, Source, FontDisplay, FontWeight};
 use gecko_bindings::bindings;
@@ -324,8 +324,8 @@ impl ToNsCssValue for counter_style::Ranges {
             nscssvalue.set_auto();
         } else {
             nscssvalue.set_pair_list(self.0.into_iter().map(|range| {
-                fn set_bound(bound: Option<i32>, nscssvalue: &mut nsCSSValue) {
+                fn set_bound(bound: CounterBound, nscssvalue: &mut nsCSSValue) {
-                    if let Some(finite) = bound {
+                    if let CounterBound::Integer(finite) = bound {
                         nscssvalue.set_integer(finite)
                     } else {
                         nscssvalue.set_enum(structs::NS_STYLE_COUNTER_RANGE_INFINITE as i32)

components/style/gecko/selector_parser.rs

@@ -66,7 +66,7 @@ apply_non_ts_list!(pseudo_class_name);
 impl ToCss for NonTSPseudoClass {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
         use cssparser::CssStringWriter;
-        use fmt::Write;
+        use std::fmt::Write;
         macro_rules! pseudo_class_serialize {
             (bare: [$(($css:expr, $name:ident, $gecko_type:tt, $state:tt, $flags:tt),)*],
              string: [$(($s_css:expr, $s_name:ident, $s_gecko_type:tt, $s_state:tt, $s_flags:tt),)*]) => {

components/style/lib.rs

@@ -133,9 +133,6 @@ pub mod traversal_flags;
 #[allow(non_camel_case_types)]
 pub mod values;
 
-use std::fmt::{self, Write};
-use style_traits::{CssWriter, ToCss};
-
 #[cfg(feature = "gecko")] pub use gecko_string_cache as string_cache;
 #[cfg(feature = "gecko")] pub use gecko_string_cache::Atom;
 #[cfg(feature = "gecko")] pub use gecko_string_cache::Namespace;
@@ -181,30 +178,6 @@ macro_rules! reexport_computed_values {
 }
 longhand_properties_idents!(reexport_computed_values);
 
-/// Serializes as CSS a comma-separated list of any `T` that supports being
-/// serialized as CSS.
-pub fn serialize_comma_separated_list<W, T>(
-    dest: &mut CssWriter<W>,
-    list: &[T],
-) -> fmt::Result
-where
-    W: Write,
-    T: ToCss,
-{
-    if list.is_empty() {
-        return Ok(());
-    }
-
-    list[0].to_css(dest)?;
-
-    for item in list.iter().skip(1) {
-        dest.write_str(", ")?;
-        item.to_css(dest)?;
-    }
-
-    Ok(())
-}
-
 #[cfg(feature = "gecko")] use gecko_string_cache::WeakAtom;
 #[cfg(feature = "servo")] use servo_atoms::Atom as WeakAtom;
 

components/style/media_queries.rs

@@ -13,7 +13,6 @@ use cssparser::{Token, ParserInput};
 use error_reporting::{ContextualParseError, ParseErrorReporter};
 use parser::{ParserContext, ParserErrorContext};
 use selectors::parser::SelectorParseErrorKind;
-use serialize_comma_separated_list;
 use std::fmt::{self, Write};
 use str::string_as_ascii_lowercase;
 use style_traits::{CssWriter, ToCss, ParseError, StyleParseErrorKind};
@@ -25,22 +24,14 @@ pub use servo::media_queries::{Device, Expression};
 pub use gecko::media_queries::{Device, Expression};
 
 /// A type that encapsulates a media query list.
-#[derive(Clone, Debug)]
 #[cfg_attr(feature = "servo", derive(MallocSizeOf))]
+#[css(comma, iterable)]
+#[derive(Clone, Debug, ToCss)]
 pub struct MediaList {
     /// The list of media queries.
     pub media_queries: Vec<MediaQuery>,
 }
 
-impl ToCss for MediaList {
-    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
-    where
-        W: Write,
-    {
-        serialize_comma_separated_list(dest, &self.media_queries)
-    }
-}
-
 impl MediaList {
     /// Create an empty MediaList.
     pub fn empty() -> Self {

components/style/properties/helpers.mako.rs

@@ -83,8 +83,10 @@
                           need_animatable=need_animatable, **kwargs)">
         #[allow(unused_imports)]
         use smallvec::SmallVec;
+        % if allow_empty:
         use std::fmt::{self, Write};
         use style_traits::{CssWriter, Separator, ToCss};
+        % endif
 
         pub mod single_value {
             #[allow(unused_imports)]
@@ -122,6 +124,14 @@
             % if need_animatable or animation_value_type == "ComputedValue":
             #[derive(Animate, ComputeSquaredDistance)]
             % endif
+            % if not allow_empty:
+            % if separator == "Comma":
+            #[css(comma, iterable)]
+            % else:
+            #[css(iterable)]
+            % endif
+            #[derive(ToCss)]
+            % endif
             pub struct T(
                 % if allow_empty and allow_empty != "NotInitial":
                 pub Vec<single_value::T>,
@@ -154,6 +164,7 @@
             }
         }
 
+        % if allow_empty:
         impl ToCss for computed_value::T {
             fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
             where
@@ -163,11 +174,7 @@
                 if let Some(val) = iter.next() {
                     val.to_css(dest)?;
                 } else {
-                    % if allow_empty:
+                    return dest.write_str("none");
-                        dest.write_str("none")?;
-                    % else:
-                        warn!("Found empty value for property ${name}");
-                    % endif
                 }
                 for i in iter {
                     dest.write_str(::style_traits::${separator}::separator())?;
@@ -176,11 +183,21 @@
                 Ok(())
             }
         }
+        % endif
 
         /// The specified value of ${name}.
         #[derive(Clone, Debug, MallocSizeOf, PartialEq)]
+        % if not allow_empty:
+        % if separator == "Comma":
+        #[css(comma, iterable)]
+        % else:
+        #[css(iterable)]
+        % endif
+        #[derive(ToCss)]
+        % endif
         pub struct SpecifiedValue(pub Vec<single_value::SpecifiedValue>);
 
+        % if allow_empty:
         impl ToCss for SpecifiedValue {
             fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
             where
@@ -190,11 +207,7 @@
                 if let Some(val) = iter.next() {
                     val.to_css(dest)?;
                 } else {
-                    % if allow_empty:
+                    return dest.write_str("none");
-                        dest.write_str("none")?;
-                    % else:
-                        warn!("Found empty value for property ${name}");
-                    % endif
                 }
                 for i in iter {
                     dest.write_str(::style_traits::${separator}::separator())?;
@@ -203,6 +216,7 @@
                 Ok(())
             }
         }
+        % endif
 
         pub fn get_initial_value() -> computed_value::T {
             % if allow_empty and allow_empty != "NotInitial":

components/style/properties/properties.mako.rs

@@ -1308,7 +1308,7 @@ impl ShorthandId {
 
 /// Servo's representation of a declared value for a given `T`, which is the
 /// declared value for that property.
-#[derive(Clone, Debug, Eq, PartialEq, ToCss)]
+#[derive(Clone, Debug, Eq, PartialEq)]
 pub enum DeclaredValue<'a, T: 'a> {
     /// A known specified value from the stylesheet.
     Value(&'a T),
@@ -1323,7 +1323,7 @@ pub enum DeclaredValue<'a, T: 'a> {
 /// extra discriminant word) and synthesize dependent DeclaredValues for
 /// PropertyDeclaration instances as needed.
 #[cfg_attr(feature = "gecko", derive(MallocSizeOf))]
-#[derive(Clone, Debug, Eq, PartialEq)]
+#[derive(Clone, Debug, Eq, PartialEq, ToCss)]
 pub enum DeclaredValueOwned<T> {
     /// A known specified value from the stylesheet.
     Value(T),
@@ -1756,7 +1756,7 @@ impl ToCss for CustomDeclaration {
     where
         W: fmt::Write,
     {
-        self.value.borrow().to_css(dest)
+        self.value.to_css(dest)
     }
 }