Auto merge of #20237 - servo:derive-all-the-things, r=emilio

Opt into field bounds when deriving ToCss, instead of opting out

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components/style/values/generics/basic_shape.rs

@@ -62,9 +62,9 @@ pub enum ShapeSource<BasicShape, ReferenceBox, ImageOrUrl> {
 #[derive(Animate, Clone, ComputeSquaredDistance, Debug, MallocSizeOf, PartialEq)]
 #[derive(ToComputedValue, ToCss)]
 pub enum BasicShape<H, V, LengthOrPercentage> {
-    Inset(InsetRect<LengthOrPercentage>),
-    Circle(Circle<H, V, LengthOrPercentage>),
-    Ellipse(Ellipse<H, V, LengthOrPercentage>),
+    Inset(#[css(field_bound)] InsetRect<LengthOrPercentage>),
+    Circle(#[css(field_bound)] Circle<H, V, LengthOrPercentage>),
+    Ellipse(#[css(field_bound)] Ellipse<H, V, LengthOrPercentage>),
     Polygon(Polygon<LengthOrPercentage>),
 }
 

components/style/values/generics/border.rs

@@ -32,7 +32,7 @@ pub struct BorderImageSlice<NumberOrPercentage> {
 /// A generic value for the `border-*-radius` longhand properties.
 #[derive(Animate, Clone, ComputeSquaredDistance, Copy, Debug)]
 #[derive(MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
-pub struct BorderCornerRadius<L>(pub Size<L>);
+pub struct BorderCornerRadius<L>(#[css(field_bound)] pub Size<L>);
 
 impl<L> BorderCornerRadius<L> {
     /// Trivially create a `BorderCornerRadius`.
@@ -44,7 +44,7 @@ impl<L> BorderCornerRadius<L> {
 /// A generic value for the `border-spacing` property.
 #[derive(Animate, Clone, ComputeSquaredDistance, Copy, Debug, MallocSizeOf)]
 #[derive(PartialEq, ToAnimatedValue, ToAnimatedZero, ToComputedValue, ToCss)]
-pub struct BorderSpacing<L>(pub Size<L>);
+pub struct BorderSpacing<L>(#[css(field_bound)] pub Size<L>);
 
 impl<L> BorderSpacing<L> {
     /// Trivially create a `BorderCornerRadius`.

components/style/values/generics/font.rs

@@ -68,8 +68,9 @@ where
 }
 
 /// A value both for font-variation-settings and font-feature-settings.
-#[derive(Clone, Debug, Eq, MallocSizeOf, PartialEq, ToComputedValue)]
-pub struct FontSettings<T>(pub Box<[T]>);
+#[css(comma)]
+#[derive(Clone, Debug, Eq, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
+pub struct FontSettings<T>(#[css(if_empty = "normal", iterable)] pub Box<[T]>);
 
 impl<T> FontSettings<T> {
     /// Default value of font settings as `normal`.
@@ -96,30 +97,6 @@ impl<T: Parse> Parse for FontSettings<T> {
     }
 }
 
-impl<T: ToCss> ToCss for FontSettings<T> {
-    /// https://drafts.csswg.org/css-fonts-4/#descdef-font-face-font-feature-settings
-    /// https://drafts.csswg.org/css-fonts-4/#font-variation-settings-def
-    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
-    where
-        W: Write,
-    {
-        if self.0.is_empty() {
-            return dest.write_str("normal");
-        }
-
-        let mut first = true;
-        for item in self.0.iter() {
-            if !first {
-                dest.write_str(", ")?;
-            }
-            first = false;
-            item.to_css(dest)?;
-        }
-
-        Ok(())
-    }
-}
-
 /// A font four-character tag, represented as a u32 for convenience.
 ///
 /// See:

components/style/values/generics/svg.rs

@@ -6,8 +6,7 @@
 
 use cssparser::Parser;
 use parser::{Parse, ParserContext};
-use std::fmt::{self, Write};
-use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
+use style_traits::{ParseError, StyleParseErrorKind};
 use values::{Either, None_};
 use values::computed::NumberOrPercentage;
 use values::computed::length::LengthOrPercentage;
@@ -199,41 +198,16 @@ pub enum SVGLength<LengthType> {
 }
 
 /// Generic value for stroke-dasharray.
-#[derive(Clone, ComputeSquaredDistance, Debug, MallocSizeOf, PartialEq, ToAnimatedValue,
-         ToComputedValue)]
+#[derive(Clone, ComputeSquaredDistance, Debug, MallocSizeOf, PartialEq)]
+#[derive(ToAnimatedValue, ToComputedValue, ToCss)]
 pub enum SVGStrokeDashArray<LengthType> {
     /// `[ <length> | <percentage> | <number> ]#`
-    Values(Vec<LengthType>),
+    #[css(comma)]
+    Values(#[css(if_empty = "none", iterable)] Vec<LengthType>),
     /// `context-value`
     ContextValue,
 }
 
-impl<LengthType> ToCss for SVGStrokeDashArray<LengthType> where LengthType: ToCss {
-    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
-    where
-        W: Write,
-    {
-        match self {
-            &SVGStrokeDashArray::Values(ref values) => {
-                let mut iter = values.iter();
-                if let Some(first) = iter.next() {
-                    first.to_css(dest)?;
-                    for item in iter {
-                        dest.write_str(", ")?;
-                        item.to_css(dest)?;
-                    }
-                    Ok(())
-                } else {
-                    dest.write_str("none")
-                }
-            }
-            &SVGStrokeDashArray::ContextValue => {
-                dest.write_str("context-value")
-            }
-        }
-    }
-}
-
 /// An SVG opacity value accepts `context-{fill,stroke}-opacity` in
 /// addition to opacity value.
 #[derive(Clone, ComputeSquaredDistance, Copy, Debug, MallocSizeOf)]

components/style/values/generics/transform.rs

@@ -7,8 +7,6 @@
 use app_units::Au;
 use euclid::{self, Rect, Transform3D};
 use num_traits::Zero;
-use std::fmt::{self, Write};
-use style_traits::{CssWriter, ToCss};
 use values::{computed, CSSFloat};
 use values::computed::length::Length as ComputedLength;
 use values::computed::length::LengthOrPercentage as ComputedLengthOrPercentage;
@@ -250,7 +248,6 @@ pub enum TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage>
     #[css(comma, function = "interpolatematrix")]
     InterpolateMatrix {
         #[compute(ignore_bound)]
-        #[css(ignore_bound)]
         from_list: Transform<
             TransformOperation<
                 Angle,
@@ -261,7 +258,6 @@ pub enum TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage>
             >,
         >,
         #[compute(ignore_bound)]
-        #[css(ignore_bound)]
         to_list: Transform<
             TransformOperation<
                 Angle,
@@ -279,7 +275,6 @@ pub enum TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage>
     #[css(comma, function = "accumulatematrix")]
     AccumulateMatrix {
         #[compute(ignore_bound)]
-        #[css(ignore_bound)]
         from_list: Transform<
             TransformOperation<
                 Angle,
@@ -290,7 +285,6 @@ pub enum TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage>
             >,
         >,
         #[compute(ignore_bound)]
-        #[css(ignore_bound)]
         to_list: Transform<
             TransformOperation<
                 Angle,
@@ -304,10 +298,9 @@ pub enum TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage>
     },
 }
 
-#[derive(Animate, ToComputedValue)]
-#[derive(Clone, Debug, MallocSizeOf, PartialEq)]
+#[derive(Animate, Clone, Debug, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
 /// A value of the `transform` property
-pub struct Transform<T>(pub Vec<T>);
+pub struct Transform<T>(#[css(if_empty = "none", iterable)] pub Vec<T>);
 
 impl<Angle, Number, Length, Integer, LengthOrPercentage>
     TransformOperation<Angle, Number, Length, Integer, LengthOrPercentage> {
@@ -515,27 +508,6 @@ where
     }
 }
 
-impl<T: ToCss> ToCss for Transform<T> {
-    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
-    where
-        W: Write,
-    {
-        if self.0.is_empty() {
-            return dest.write_str("none");
-        }
-
-        let mut first = true;
-        for operation in &self.0 {
-            if !first {
-                dest.write_str(" ")?;
-            }
-            first = false;
-            operation.to_css(dest)?
-        }
-        Ok(())
-    }
-}
-
 impl<T> Transform<T> {
     /// `none`
     pub fn none() -> Self {