Add animated value for stroke-*.

SMIL animation which fill mode equal 'freeze' will use the specified from/to value,
current servo use SvgLengthOrPercentageOrNumber, so animated value when an animation
is finished will be LengthOrPercentage value.

i.e.
 If we animate between '20' and '10px'(<animate from='20' to='10px' fill='freeze'>):
    0%   -> 20
    50%  -> 15
    100% -> 10px

 The result of computed value contains unit since smil use specified 'to' value.

SMIL implementation of gecko side will call Servo_ParseProperty when specified
fill='freeze' and animation finished.

So this PR add animated value for stroke-* property. This animated value
contains the calc() value, but gecko side implementation doesn't support calc().
For detail, see https://bugzilla.mozilla.org/show_bug.cgi?id=1386967.

components/style/properties/helpers/animated_properties.mako.rs

@@ -43,21 +43,21 @@ use values::animated::effects::BoxShadowList as AnimatedBoxShadowList;
 use values::animated::effects::Filter as AnimatedFilter;
 use values::animated::effects::FilterList as AnimatedFilterList;
 use values::animated::effects::TextShadowList as AnimatedTextShadowList;
+use values::animated::svg::SvgLengthOrPercentageOrNumber as AnimatedSvgLengthOrPercentageOrNumber;
 use values::computed::{Angle, BorderCornerRadius, CalcLengthOrPercentage};
 use values::computed::{ClipRect, Context, ComputedUrl, ComputedValueAsSpecified};
 use values::computed::{LengthOrPercentage, LengthOrPercentageOrAuto};
 use values::computed::{LengthOrPercentageOrNone, MaxLength, NonNegativeAu};
-use values::computed::{NonNegativeNumber, Number, NumberOrPercentage, Percentage};
-use values::computed::{PositiveIntegerOrAuto, ToComputedValue};
-#[cfg(feature = "gecko")] use values::computed::MozLength;
+use values::computed::{NonNegativeNumber, Percentage, PositiveIntegerOrAuto};
+use values::computed::ToComputedValue;
 use values::computed::length::{NonNegativeLengthOrAuto, NonNegativeLengthOrNormal};
 use values::computed::length::NonNegativeLengthOrPercentage;
 use values::computed::transform::DirectionVector;
 use values::distance::{ComputeSquaredDistance, SquaredDistance};
 use values::generics::NonNegative;
 use values::generics::effects::Filter;
 use values::generics::position as generic_position;
-use values::generics::svg::{SVGLength,  SvgLengthOrPercentageOrNumber, SVGPaint};
+use values::generics::svg::{SVGLength, SVGPaint};
 use values::generics::svg::{SVGPaintKind, SVGStrokeDashArray, SVGOpacity};
 
 /// https://drafts.csswg.org/css-transitions/#animtype-repeatable-list
@@ -713,7 +713,7 @@ impl ToAnimatedZero for AnimationValue {
 impl RepeatableListAnimatable for LengthOrPercentage {}
 impl RepeatableListAnimatable for Either<f32, LengthOrPercentage> {}
 impl RepeatableListAnimatable for Either<NonNegativeNumber, NonNegativeLengthOrPercentage> {}
-impl RepeatableListAnimatable for SvgLengthOrPercentageOrNumber<NonNegativeLengthOrPercentage, NonNegativeNumber> {}
+impl RepeatableListAnimatable for AnimatedSvgLengthOrPercentageOrNumber {}
 
 macro_rules! repeated_vec_impl {
     ($($ty:ty),*) => {
@@ -2277,112 +2277,6 @@ impl ToAnimatedZero for IntermediateSVGPaint {
     }
 }
 
-impl From<NonNegativeLengthOrPercentage> for NumberOrPercentage {
-    fn from(lop: NonNegativeLengthOrPercentage) -> NumberOrPercentage {
-        lop.0.into()
-    }
-}
-
-impl From<NonNegativeNumber> for NumberOrPercentage {
-    fn from(num: NonNegativeNumber) -> NumberOrPercentage {
-        num.0.into()
-    }
-}
-
-impl From<LengthOrPercentage> for NumberOrPercentage {
-    fn from(lop: LengthOrPercentage) -> NumberOrPercentage {
-        match lop {
-            LengthOrPercentage::Length(len) => {
-                NumberOrPercentage::Number(len.to_f32_px())
-            },
-            LengthOrPercentage::Percentage(p) => {
-                NumberOrPercentage::Percentage(p)
-            },
-            LengthOrPercentage::Calc(_) => {
-                panic!("We dont't expected calc interpolation for SvgLengthOrPercentageOrNumber");
-            },
-        }
-    }
-}
-
-impl From<Number> for NumberOrPercentage {
-    fn from(num: Number) -> NumberOrPercentage {
-        NumberOrPercentage::Number(num)
-    }
-}
-
-fn convert_to_number_or_percentage<L, N>(from: SvgLengthOrPercentageOrNumber<L, N>)
-    -> NumberOrPercentage
-    where
-        L: Into<NumberOrPercentage>,
-        N: Into<NumberOrPercentage>
-{
-    match from {
-        SvgLengthOrPercentageOrNumber::LengthOrPercentage(lop) =>
-        {
-            lop.into()
-        }
-        SvgLengthOrPercentageOrNumber::Number(num) =>
-        {
-            num.into()
-        }
-    }
-}
-
-fn convert_from_number_or_percentage<L, N>(from: NumberOrPercentage)
-    -> SvgLengthOrPercentageOrNumber<L, N>
-    where
-        L: From<LengthOrPercentage>,
-        N: From<Number>
-{
-    match from {
-        NumberOrPercentage::Number(num) =>
-            SvgLengthOrPercentageOrNumber::Number(From::from(num)),
-        NumberOrPercentage::Percentage(p) =>
-            SvgLengthOrPercentageOrNumber::LengthOrPercentage(
-                (LengthOrPercentage::Percentage(p)).into())
-    }
-}
-
-impl <L, N> Animate for SvgLengthOrPercentageOrNumber<L, N>
-where
-    L: Animate + From<LengthOrPercentage> + Into<NumberOrPercentage> + Copy,
-    N: Animate + From<Number> + Into<NumberOrPercentage>,
-    LengthOrPercentage: From<L>,
-    Self: Copy,
-{
-    #[inline]
-    fn animate(&self, other: &Self, procedure: Procedure) -> Result<Self, ()> {
-        if self.has_calc() || other.has_calc() {
-            // TODO: We need to treat calc value.
-            // https://bugzilla.mozilla.org/show_bug.cgi?id=1386967
-            return Err(());
-        }
-
-        let this = convert_to_number_or_percentage(*self);
-        let other = convert_to_number_or_percentage(*other);
-
-        match (this, other) {
-            (
-                NumberOrPercentage::Number(ref this),
-                NumberOrPercentage::Number(ref other),
-            ) => {
-                Ok(convert_from_number_or_percentage(
-                    NumberOrPercentage::Number(this.animate(other, procedure)?)
-                ))
-            },
-            (
-                NumberOrPercentage::Percentage(ref this),
-                NumberOrPercentage::Percentage(ref other),
-            ) => {
-                Ok(convert_from_number_or_percentage(
-                    NumberOrPercentage::Percentage(this.animate(other, procedure)?)
-                ))
-            },
-            _ => Err(()),
-        }
-    }
-}
 
 impl<L> Animate for SVGLength<L>
 where

components/style/properties/longhand/inherited_svg.mako.rs

@@ -68,7 +68,7 @@ ${helpers.predefined_type(
     "::values::computed::NonNegativeAu::from_px(1).into()",
     products="gecko",
     boxed="True",
-    animation_value_type="::values::computed::SVGWidth",
+    animation_value_type="<::values::computed::SVGWidth as ToAnimatedValue>::AnimatedValue",
     spec="https://www.w3.org/TR/SVG2/painting.html#StrokeWidth")}
 
 ${helpers.single_keyword("stroke-linecap", "butt round square",
@@ -94,7 +94,7 @@ ${helpers.predefined_type(
     "SVGStrokeDashArray",
     "Default::default()",
     products="gecko",
-    animation_value_type="::values::computed::SVGStrokeDashArray",
+    animation_value_type="<::values::computed::SVGStrokeDashArray as ToAnimatedValue>::AnimatedValue",
     spec="https://www.w3.org/TR/SVG2/painting.html#StrokeDashing",
 )}
 
@@ -103,7 +103,7 @@ ${helpers.predefined_type(
     "Au(0).into()",
     products="gecko",
     boxed="True",
-    animation_value_type="ComputedValue",
+    animation_value_type="<::values::computed::SVGLength as ToAnimatedValue>::AnimatedValue",
     spec="https://www.w3.org/TR/SVG2/painting.html#StrokeDashing")}
 
 // Section 14 - Clipping, Masking and Compositing

components/style/values/animated/mod.rs

@@ -27,6 +27,7 @@ use values::specified::url::SpecifiedUrl;
 
 pub mod color;
 pub mod effects;
+pub mod svg;
 
 /// Animate from one value to another.
 ///

components/style/values/animated/svg.rs

@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//! Animated types for CSS values in SVG
+
+use values::computed::{Number, Percentage};
+use values::computed::length::CalcLengthOrPercentage;
+
+/// Stroke-* value support unit less value, so servo interpolate length value as
+/// number unlike computed value and specified value.
+#[derive(Animate, Clone, ComputeSquaredDistance, Copy, Debug, PartialEq, ToAnimatedZero)]
+pub enum SvgLengthOrPercentageOrNumber {
+    /// Real number value.
+    Number(Number),
+    /// Percentage value.
+    Percentage(Percentage),
+    /// Calc value, this type can hold percentage value. For present, percentage
+    /// value store the Percentage type.(i.e. Servo doesn't use CalcLengthOrPercentage
+    /// for storing the percentage value)
+    /// TODO: We need to support interpolation of calc value.
+    /// https://bugzilla.mozilla.org/show_bug.cgi?id=1386967
+    #[animation(error)]
+    Calc(CalcLengthOrPercentage),
+}

components/style/values/generics/svg.rs

@@ -4,13 +4,16 @@
 
 //! Generic types for CSS values in SVG
 
+use app_units::Au;
 use cssparser::Parser;
 use parser::{Parse, ParserContext};
 use std::fmt;
 use style_traits::{ParseError, StyleParseError, ToCss};
-use values::computed::NumberOrPercentage;
-use values::computed::length::LengthOrPercentage;
-use values::distance::{ComputeSquaredDistance, SquaredDistance};
+use values::animated::ToAnimatedValue;
+use values::animated::svg::SvgLengthOrPercentageOrNumber as AnimatedSvgLengthOrPercentageOrNumber;
+use values::computed::{NonNegativeNumber, Number};
+use values::computed::length::{CalcLengthOrPercentage, LengthOrPercentage};
+use values::computed::length::NonNegativeLengthOrPercentage;
 
 /// An SVG paint value
 ///
@@ -104,65 +107,97 @@ impl<ColorType: Parse, UrlPaintServer: Parse> Parse for SVGPaint<ColorType, UrlP
 /// A value of <length> | <percentage> | <number> for svg which allow unitless length.
 /// https://www.w3.org/TR/SVG11/painting.html#StrokeProperties
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-#[derive(Clone, Copy, Debug, PartialEq, ToAnimatedValue)]
-#[derive(ToAnimatedZero, ToComputedValue, ToCss)]
+#[derive(Clone, Copy, Debug, PartialEq, ToComputedValue, ToCss)]
 pub enum SvgLengthOrPercentageOrNumber<L, N> {
     /// <length> | <percentage>
     LengthOrPercentage(L),
     /// <number>
     Number(N),
 }
 
-impl<L, N> ComputeSquaredDistance for SvgLengthOrPercentageOrNumber<L, N>
+/// Following From implements use for converting animated value.
+impl<L, N> ToAnimatedValue for SvgLengthOrPercentageOrNumber<L, N>
     where
-        L: ComputeSquaredDistance + Copy + Into<NumberOrPercentage>,
-        N: ComputeSquaredDistance + Copy + Into<NumberOrPercentage>
+        L: Into<AnimatedSvgLengthOrPercentageOrNumber> + From<LengthOrPercentage>,
+        N: Into<AnimatedSvgLengthOrPercentageOrNumber> + From<Number>
 {
+    type AnimatedValue = AnimatedSvgLengthOrPercentageOrNumber;
+
     #[inline]
-    fn compute_squared_distance(&self, other: &Self) -> Result<SquaredDistance, ()> {
-        match (self, other) {
-            (
-                &SvgLengthOrPercentageOrNumber::LengthOrPercentage(ref from),
-                &SvgLengthOrPercentageOrNumber::LengthOrPercentage(ref to)
-            ) => {
-                from.compute_squared_distance(to)
-            },
-            (
-                &SvgLengthOrPercentageOrNumber::Number(ref from),
-                &SvgLengthOrPercentageOrNumber::Number(ref to)
-            ) => {
-                from.compute_squared_distance(to)
+    fn to_animated_value(self) -> Self::AnimatedValue {
+        match self {
+            SvgLengthOrPercentageOrNumber::LengthOrPercentage(lop) => lop.into(),
+            SvgLengthOrPercentageOrNumber::Number(num) => num.into(),
+        }
+    }
+
+    #[inline]
+    fn from_animated_value(animated: Self::AnimatedValue) -> Self {
+        match animated {
+            AnimatedSvgLengthOrPercentageOrNumber::Number(num) =>
+            {
+                SvgLengthOrPercentageOrNumber::Number(From::from(num))
             },
-            (
-                &SvgLengthOrPercentageOrNumber::LengthOrPercentage(from),
-                &SvgLengthOrPercentageOrNumber::Number(to)
-            ) => {
-                from.into().compute_squared_distance(&to.into())
+            AnimatedSvgLengthOrPercentageOrNumber::Percentage(p) =>
+            {
+                SvgLengthOrPercentageOrNumber::LengthOrPercentage(
+                    From::from(LengthOrPercentage::Percentage(p)))
             },
-            (
-                &SvgLengthOrPercentageOrNumber::Number(from),
-                &SvgLengthOrPercentageOrNumber::LengthOrPercentage(to)
-            ) => {
-                from.into().compute_squared_distance(&to.into())
+            AnimatedSvgLengthOrPercentageOrNumber::Calc(calc) =>
+            {
+                SvgLengthOrPercentageOrNumber::LengthOrPercentage(
+                    From::from(LengthOrPercentage::Calc(calc)))
             },
         }
     }
 }
 
-impl<L, N> SvgLengthOrPercentageOrNumber<L, N>
-    where
-        L: Into<LengthOrPercentage> + Copy
-{
-    /// return true if this struct has calc value.
-    pub fn has_calc(&self) -> bool {
-        match self {
-            &SvgLengthOrPercentageOrNumber::LengthOrPercentage(lop) => {
-                match lop.into() {
-                    LengthOrPercentage::Calc(_) => true,
-                    _ => false,
-                }
+/// We need to a following conversion bounds for converting to an animated
+/// value of SvgLengthOrPercentageOrNumber.
+impl From<NonNegativeLengthOrPercentage> for AnimatedSvgLengthOrPercentageOrNumber {
+    fn from(lop: NonNegativeLengthOrPercentage) -> AnimatedSvgLengthOrPercentageOrNumber {
+        lop.0.into()
+    }
+}
+
+impl From<NonNegativeNumber> for AnimatedSvgLengthOrPercentageOrNumber {
+    fn from(num: NonNegativeNumber) -> AnimatedSvgLengthOrPercentageOrNumber {
+        num.0.into()
+    }
+}
+
+impl From<LengthOrPercentage> for AnimatedSvgLengthOrPercentageOrNumber {
+    fn from(lop: LengthOrPercentage) -> AnimatedSvgLengthOrPercentageOrNumber {
+        match lop {
+            LengthOrPercentage::Length(len) => {
+                AnimatedSvgLengthOrPercentageOrNumber::Number(len.to_f32_px())
+            },
+            LengthOrPercentage::Percentage(p) => {
+                AnimatedSvgLengthOrPercentageOrNumber::Percentage(p)
             },
-            _ => false,
+            LengthOrPercentage::Calc(calc) => {
+                AnimatedSvgLengthOrPercentageOrNumber::Calc(calc.into())
+            },
+        }
+    }
+
+}
+
+impl From<Number> for AnimatedSvgLengthOrPercentageOrNumber {
+    fn from(num: Number) -> AnimatedSvgLengthOrPercentageOrNumber {
+        AnimatedSvgLengthOrPercentageOrNumber::Number(num)
+    }
+}
+
+impl From<AnimatedSvgLengthOrPercentageOrNumber> for CalcLengthOrPercentage {
+    fn from(nopoc: AnimatedSvgLengthOrPercentageOrNumber) -> CalcLengthOrPercentage {
+        match nopoc {
+            AnimatedSvgLengthOrPercentageOrNumber::Number(num) =>
+                CalcLengthOrPercentage::new(Au::from_f32_px(num), None),
+            AnimatedSvgLengthOrPercentageOrNumber::Percentage(p) =>
+                CalcLengthOrPercentage::new(Au(0), Some(p)),
+            AnimatedSvgLengthOrPercentageOrNumber::Calc(calc) =>
+                calc.into(),
         }
     }
 }
@@ -197,7 +232,8 @@ pub enum SVGLength<LengthType> {
 
 /// Generic value for stroke-dasharray.
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-#[derive(Clone, ComputeSquaredDistance, Debug, PartialEq, ToAnimatedValue, ToComputedValue)]
+#[derive(Clone, ComputeSquaredDistance, Debug, PartialEq)]
+#[derive(ToAnimatedValue, ToComputedValue)]
 pub enum SVGStrokeDashArray<LengthType> {
     /// `[ <length> | <percentage> | <number> ]#`
     Values(Vec<LengthType>),