style: Clamp to non-negative value after doing interpolation for circle(), ellipse(), and inset().

Replace LengthOrPercentage with NonNegativeLengthOrPercentage on
ShapeRadius, Circle, Ellipse. And derive ToAnimatedValue for ShapeSource and
its related types, so we clamp its interpolated results into non-negative
values. (i.e. The radius of circle()/ellipse() and the border-radius of
inset().)

Note: We may get negative values when using a negative easing function, so the
clamp is necessary to avoid the incorrect result or any undefined behavior.

Differential Revision: https://phabricator.services.mozilla.com/D14654

components/style/values/animated/mod.rs

@@ -12,7 +12,9 @@ use crate::properties::PropertyId;
 use crate::values::computed::length::CalcLengthOrPercentage;
 use crate::values::computed::url::ComputedUrl;
 use crate::values::computed::Angle as ComputedAngle;
+use crate::values::computed::Image;
 use crate::values::CSSFloat;
+use crate::values::specified::SVGPathData;
 use app_units::Au;
 use euclid::{Point2D, Size2D};
 use smallvec::SmallVec;
@@ -338,6 +340,19 @@ trivial_to_animated_value!(ComputedAngle);
 trivial_to_animated_value!(ComputedUrl);
 trivial_to_animated_value!(bool);
 trivial_to_animated_value!(f32);
+// Note: This implementation is for ToAnimatedValue of ShapeSource.
+//
+// SVGPathData uses Box<[T]>. If we want to derive ToAnimatedValue for all the
+// types, we have to do "impl ToAnimatedValue for Box<[T]>" first.
+// However, the general version of "impl ToAnimatedValue for Box<[T]>" needs to
+// clone |T| and convert it into |T::AnimatedValue|. However, for SVGPathData
+// that is unnecessary--moving |T| is sufficient. So here, we implement this
+// trait manually.
+trivial_to_animated_value!(SVGPathData);
+// FIXME: Bug 1514342, Image is not animatable, but we still need to implement
+// this to avoid adding this derive to generic::Image and all its arms. We can
+// drop this after landing Bug 1514342.
+trivial_to_animated_value!(Image);
 
 impl ToAnimatedZero for Au {
     #[inline]

components/style/values/computed/basic_shape.rs

@@ -23,20 +23,26 @@ pub type ClippingShape = generic::ClippingShape<BasicShape, ComputedUrl>;
 pub type FloatAreaShape = generic::FloatAreaShape<BasicShape, Image>;
 
 /// A computed basic shape.
-pub type BasicShape =
-    generic::BasicShape<LengthOrPercentage, LengthOrPercentage, LengthOrPercentage, NonNegativeLengthOrPercentage>;
+pub type BasicShape = generic::BasicShape<
+    LengthOrPercentage,
+    LengthOrPercentage,
+    LengthOrPercentage,
+    NonNegativeLengthOrPercentage,
+>;
 
 /// The computed value of `inset()`
 pub type InsetRect = generic::InsetRect<LengthOrPercentage, NonNegativeLengthOrPercentage>;
 
 /// A computed circle.
-pub type Circle = generic::Circle<LengthOrPercentage, LengthOrPercentage, LengthOrPercentage>;
+pub type Circle =
+    generic::Circle<LengthOrPercentage, LengthOrPercentage, NonNegativeLengthOrPercentage>;
 
 /// A computed ellipse.
-pub type Ellipse = generic::Ellipse<LengthOrPercentage, LengthOrPercentage, LengthOrPercentage>;
+pub type Ellipse =
+    generic::Ellipse<LengthOrPercentage, LengthOrPercentage, NonNegativeLengthOrPercentage>;
 
 /// The computed value of `ShapeRadius`
-pub type ShapeRadius = generic::ShapeRadius<LengthOrPercentage>;
+pub type ShapeRadius = generic::ShapeRadius<NonNegativeLengthOrPercentage>;
 
 impl ToCss for Circle {
     fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result

components/style/values/generics/basic_shape.rs

@@ -20,7 +20,16 @@ pub type ClippingShape<BasicShape, Url> = ShapeSource<BasicShape, GeometryBox, U
 /// <https://drafts.fxtf.org/css-masking-1/#typedef-geometry-box>
 #[allow(missing_docs)]
 #[derive(
-    Animate, Clone, Copy, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue, ToCss,
+    Animate,
+    Clone,
+    Copy,
+    Debug,
+    MallocSizeOf,
+    PartialEq,
+    SpecifiedValueInfo,
+    ToAnimatedValue,
+    ToComputedValue,
+    ToCss,
 )]
 pub enum GeometryBox {
     FillBox,
@@ -45,6 +54,7 @@ pub type FloatAreaShape<BasicShape, Image> = ShapeSource<BasicShape, ShapeBox, I
     Parse,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
     ToCss,
 )]
@@ -59,7 +69,15 @@ pub enum ShapeBox {
 #[allow(missing_docs)]
 #[animation(no_bound(ImageOrUrl))]
 #[derive(
-    Animate, Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue, ToCss,
+    Animate,
+    Clone,
+    Debug,
+    MallocSizeOf,
+    PartialEq,
+    SpecifiedValueInfo,
+    ToAnimatedValue,
+    ToComputedValue,
+    ToCss,
 )]
 pub enum ShapeSource<BasicShape, ReferenceBox, ImageOrUrl> {
     #[animation(error)]
@@ -82,13 +100,14 @@ pub enum ShapeSource<BasicShape, ReferenceBox, ImageOrUrl> {
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
     ToCss,
 )]
 pub enum BasicShape<H, V, LengthOrPercentage, NonNegativeLengthOrPercentage> {
     Inset(#[css(field_bound)] InsetRect<LengthOrPercentage, NonNegativeLengthOrPercentage>),
-    Circle(#[css(field_bound)] Circle<H, V, LengthOrPercentage>),
-    Ellipse(#[css(field_bound)] Ellipse<H, V, LengthOrPercentage>),
+    Circle(#[css(field_bound)] Circle<H, V, NonNegativeLengthOrPercentage>),
+    Ellipse(#[css(field_bound)] Ellipse<H, V, NonNegativeLengthOrPercentage>),
     Polygon(Polygon<LengthOrPercentage>),
 }
 
@@ -103,6 +122,7 @@ pub enum BasicShape<H, V, LengthOrPercentage, NonNegativeLengthOrPercentage> {
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
 )]
 pub struct InsetRect<LengthOrPercentage, NonNegativeLengthOrPercentage> {
@@ -122,11 +142,12 @@ pub struct InsetRect<LengthOrPercentage, NonNegativeLengthOrPercentage> {
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
 )]
-pub struct Circle<H, V, LengthOrPercentage> {
+pub struct Circle<H, V, NonNegativeLengthOrPercentage> {
     pub position: Position<H, V>,
-    pub radius: ShapeRadius<LengthOrPercentage>,
+    pub radius: ShapeRadius<NonNegativeLengthOrPercentage>,
 }
 
 /// <https://drafts.csswg.org/css-shapes/#funcdef-ellipse>
@@ -141,12 +162,13 @@ pub struct Circle<H, V, LengthOrPercentage> {
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
 )]
-pub struct Ellipse<H, V, LengthOrPercentage> {
+pub struct Ellipse<H, V, NonNegativeLengthOrPercentage> {
     pub position: Position<H, V>,
-    pub semiaxis_x: ShapeRadius<LengthOrPercentage>,
-    pub semiaxis_y: ShapeRadius<LengthOrPercentage>,
+    pub semiaxis_x: ShapeRadius<NonNegativeLengthOrPercentage>,
+    pub semiaxis_y: ShapeRadius<NonNegativeLengthOrPercentage>,
 }
 
 /// <https://drafts.csswg.org/css-shapes/#typedef-shape-radius>
@@ -160,11 +182,12 @@ pub struct Ellipse<H, V, LengthOrPercentage> {
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
     ToCss,
 )]
-pub enum ShapeRadius<LengthOrPercentage> {
-    Length(LengthOrPercentage),
+pub enum ShapeRadius<NonNegativeLengthOrPercentage> {
+    Length(NonNegativeLengthOrPercentage),
     #[animation(error)]
     ClosestSide,
     #[animation(error)]
@@ -175,7 +198,16 @@ pub enum ShapeRadius<LengthOrPercentage> {
 ///
 /// <https://drafts.csswg.org/css-shapes/#funcdef-polygon>
 #[css(comma, function)]
-#[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue, ToCss)]
+#[derive(
+    Clone,
+    Debug,
+    MallocSizeOf,
+    PartialEq,
+    SpecifiedValueInfo,
+    ToAnimatedValue,
+    ToComputedValue,
+    ToCss,
+)]
 pub struct Polygon<LengthOrPercentage> {
     /// The filling rule for a polygon.
     #[css(skip_if = "fill_is_default")]
@@ -186,7 +218,16 @@ pub struct Polygon<LengthOrPercentage> {
 }
 
 /// Coordinates for Polygon.
-#[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue, ToCss)]
+#[derive(
+    Clone,
+    Debug,
+    MallocSizeOf,
+    PartialEq,
+    SpecifiedValueInfo,
+    ToAnimatedValue,
+    ToComputedValue,
+    ToCss,
+)]
 pub struct PolygonCoord<LengthOrPercentage>(pub LengthOrPercentage, pub LengthOrPercentage);
 
 // https://drafts.csswg.org/css-shapes/#typedef-fill-rule
@@ -204,6 +245,7 @@ pub struct PolygonCoord<LengthOrPercentage>(pub LengthOrPercentage, pub LengthOr
     Parse,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
     ToCss,
 )]
@@ -218,7 +260,15 @@ pub enum FillRule {
 /// https://drafts.csswg.org/css-shapes-2/#funcdef-path
 #[css(comma)]
 #[derive(
-    Animate, Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue, ToCss,
+    Animate,
+    Clone,
+    Debug,
+    MallocSizeOf,
+    PartialEq,
+    SpecifiedValueInfo,
+    ToAnimatedValue,
+    ToComputedValue,
+    ToCss,
 )]
 pub struct Path {
     /// The filling rule for the svg path.

components/style/values/generics/border.rs

@@ -95,6 +95,7 @@ impl<L> BorderSpacing<L> {
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
 )]
 pub struct BorderRadius<LengthOrPercentage> {

components/style/values/generics/position.rs

@@ -15,6 +15,7 @@
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToAnimatedZero,
     ToComputedValue,
 )]

components/style/values/generics/rect.rs

@@ -20,6 +20,7 @@ use style_traits::{CssWriter, ParseError, ToCss};
     MallocSizeOf,
     PartialEq,
     SpecifiedValueInfo,
+    ToAnimatedValue,
     ToComputedValue,
 )]
 pub struct Rect<T>(pub T, pub T, pub T, pub T);

components/style/values/specified/basic_shape.rs

@@ -32,19 +32,26 @@ pub type ClippingShape = generic::ClippingShape<BasicShape, SpecifiedUrl>;
 pub type FloatAreaShape = generic::FloatAreaShape<BasicShape, Image>;
 
 /// A specified basic shape.
-pub type BasicShape = generic::BasicShape<HorizontalPosition, VerticalPosition, LengthOrPercentage, NonNegativeLengthOrPercentage>;
+pub type BasicShape = generic::BasicShape<
+    HorizontalPosition,
+    VerticalPosition,
+    LengthOrPercentage,
+    NonNegativeLengthOrPercentage,
+>;
 
 /// The specified value of `inset()`
 pub type InsetRect = generic::InsetRect<LengthOrPercentage, NonNegativeLengthOrPercentage>;
 
 /// A specified circle.
-pub type Circle = generic::Circle<HorizontalPosition, VerticalPosition, LengthOrPercentage>;
+pub type Circle =
+    generic::Circle<HorizontalPosition, VerticalPosition, NonNegativeLengthOrPercentage>;
 
 /// A specified ellipse.
-pub type Ellipse = generic::Ellipse<HorizontalPosition, VerticalPosition, LengthOrPercentage>;
+pub type Ellipse =
+    generic::Ellipse<HorizontalPosition, VerticalPosition, NonNegativeLengthOrPercentage>;
 
 /// The specified value of `ShapeRadius`
-pub type ShapeRadius = generic::ShapeRadius<LengthOrPercentage>;
+pub type ShapeRadius = generic::ShapeRadius<NonNegativeLengthOrPercentage>;
 
 /// The specified value of `Polygon`
 pub type Polygon = generic::Polygon<LengthOrPercentage>;
@@ -309,7 +316,7 @@ impl Parse for ShapeRadius {
         context: &ParserContext,
         input: &mut Parser<'i, 't>,
     ) -> Result<Self, ParseError<'i>> {
-        if let Ok(lop) = input.try(|i| LengthOrPercentage::parse_non_negative(context, i)) {
+        if let Ok(lop) = input.try(|i| NonNegativeLengthOrPercentage::parse(context, i)) {
             return Ok(generic::ShapeRadius::Length(lop));
         }