Bug 1374233 - Part 1: Add NonNegativeNumber and GreaterThanOrEqualToOneNumber.

NonNegativeNumber: for -moz-box-flex, flex-grow, and flex-shrink.
GreaterThanOrEqualToOneNumber: for stroke-miterlimit.

MozReview-Commit-ID: Kgbt99BPdVA

12 files changed, 181 insertions, 26 deletions

diff --git a/components/layout/flex.rs b/components/layout/flex.rs
index 353c939f58b..577e9a167de 100644
--- a/components/layout/flex.rs
+++ b/components/layout/flex.rs
@@ -137,8 +137,8 @@ impl FlexItem {
             min_size: Au(0),
             max_size: MAX_AU,
             index: index,
-            flex_grow: flex_grow,
-            flex_shrink: flex_shrink,
+            flex_grow: flex_grow.into(),
+            flex_shrink: flex_shrink.into(),
             order: order,
             is_frozen: false,
             is_strut: false
diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 839fdeb1dc7..e256394dea5 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -397,14 +397,14 @@ impl ${style_struct.gecko_struct_name} {
 <%def name="impl_simple_setter(ident, gecko_ffi_name)">
     #[allow(non_snake_case)]
     pub fn set_${ident}(&mut self, v: longhands::${ident}::computed_value::T) {
-        ${set_gecko_property(gecko_ffi_name, "v")}
+        ${set_gecko_property(gecko_ffi_name, "From::from(v)")}
     }
 </%def>
 
 <%def name="impl_simple_clone(ident, gecko_ffi_name)">
     #[allow(non_snake_case)]
     pub fn clone_${ident}(&self) -> longhands::${ident}::computed_value::T {
-        self.gecko.${gecko_ffi_name}
+        From::from(self.gecko.${gecko_ffi_name})
     }
 </%def>
 
@@ -1088,6 +1088,7 @@ impl Clone for ${style_struct.gecko_struct_name} {
     predefined_types = {
         "length::LengthOrAuto": impl_style_coord,
         "length::LengthOrNormal": impl_style_coord,
+        "GreaterThanOrEqualToOneNumber": impl_simple,
         "Length": impl_absolute_length,
         "Position": impl_position,
         "LengthOrPercentage": impl_style_coord,
@@ -1097,6 +1098,7 @@ impl Clone for ${style_struct.gecko_struct_name} {
         "LengthOrNormal": impl_style_coord,
         "MaxLength": impl_style_coord,
         "MozLength": impl_style_coord,
+        "NonNegativeNumber": impl_simple,
         "Number": impl_simple,
         "Integer": impl_simple,
         "Opacity": impl_simple,
diff --git a/components/style/properties/helpers/animated_properties.mako.rs b/components/style/properties/helpers/animated_properties.mako.rs
index 4419e2921fe..1957c7d3268 100644
--- a/components/style/properties/helpers/animated_properties.mako.rs
+++ b/components/style/properties/helpers/animated_properties.mako.rs
@@ -43,6 +43,8 @@ use values::computed::{Angle, LengthOrPercentageOrAuto, LengthOrPercentageOrNone
 use values::computed::{BorderCornerRadius, ClipRect};
 use values::computed::{CalcLengthOrPercentage, Color, Context, ComputedValueAsSpecified};
 use values::computed::{LengthOrPercentage, MaxLength, MozLength, Percentage, ToComputedValue};
+use values::computed::NonNegativeNumber;
+use values::generics::{GreaterThanOrEqualToOne, NonNegative};
 use values::generics::border::BorderCornerRadius as GenericBorderCornerRadius;
 use values::generics::effects::Filter;
 use values::generics::position as generic_position;
@@ -3366,3 +3368,49 @@ sorted_shorthands = [(p, position) for position, p in enumerate(sorted_shorthand
         % endfor
     }
 }
+
+impl<T> Animatable for NonNegative<T>
+    where T: Animatable + Clone
+{
+    #[inline]
+    fn add_weighted(&self, other: &Self, self_portion: f64, other_portion: f64) -> Result<Self, ()> {
+        self.0.add_weighted(&other.0, self_portion, other_portion).map(NonNegative::<T>)
+    }
+
+    #[inline]
+    fn compute_distance(&self, other: &Self) -> Result<f64, ()> {
+        self.0.compute_distance(&other.0)
+    }
+}
+
+impl<T> ToAnimatedZero for NonNegative<T>
+    where T: ToAnimatedZero
+{
+    #[inline]
+    fn to_animated_zero(&self) -> Result<Self, ()> {
+        self.0.to_animated_zero().map(NonNegative::<T>)
+    }
+}
+
+impl<T> Animatable for GreaterThanOrEqualToOne<T>
+    where T: Animatable + Clone
+{
+    #[inline]
+    fn add_weighted(&self, other: &Self, self_portion: f64, other_portion: f64) -> Result<Self, ()> {
+        self.0.add_weighted(&other.0, self_portion, other_portion).map(GreaterThanOrEqualToOne::<T>)
+    }
+
+    #[inline]
+    fn compute_distance(&self, other: &Self) -> Result<f64, ()> {
+        self.0.compute_distance(&other.0)
+    }
+}
+
+impl<T> ToAnimatedZero for GreaterThanOrEqualToOne<T>
+    where T: ToAnimatedZero
+{
+    #[inline]
+    fn to_animated_zero(&self) -> Result<Self, ()> {
+        self.0.to_animated_zero().map(GreaterThanOrEqualToOne::<T>)
+    }
+}
diff --git a/components/style/properties/longhand/inherited_svg.mako.rs b/components/style/properties/longhand/inherited_svg.mako.rs
index a5bd2fdb35e..9828ca030dd 100644
--- a/components/style/properties/longhand/inherited_svg.mako.rs
+++ b/components/style/properties/longhand/inherited_svg.mako.rs
@@ -80,9 +80,10 @@ ${helpers.single_keyword("stroke-linejoin", "miter round bevel",
                          products="gecko", animation_value_type="discrete",
                          spec="https://www.w3.org/TR/SVG11/painting.html#StrokeLinejoinProperty")}
 
-${helpers.predefined_type("stroke-miterlimit", "Number", "4.0",
-                          "parse_at_least_one", products="gecko",
-                          animation_value_type="ComputedValue",
+${helpers.predefined_type("stroke-miterlimit", "GreaterThanOrEqualToOneNumber",
+                          "From::from(4.0)",
+                          products="gecko",
+                          animation_value_type="::values::computed::GreaterThanOrEqualToOneNumber",
                           spec="https://www.w3.org/TR/SVG11/painting.html#StrokeMiterlimitProperty")}
 
 ${helpers.predefined_type("stroke-opacity", "SVGOpacity", "Default::default()",
diff --git a/components/style/properties/longhand/position.mako.rs b/components/style/properties/longhand/position.mako.rs
index dd1cb9d5724..c5e06f235cd 100644
--- a/components/style/properties/longhand/position.mako.rs
+++ b/components/style/properties/longhand/position.mako.rs
@@ -117,17 +117,17 @@ ${helpers.single_keyword("flex-wrap", "nowrap wrap wrap-reverse",
 % endif
 
 // Flex item properties
-${helpers.predefined_type("flex-grow", "Number",
-                          "0.0", "parse_non_negative",
+${helpers.predefined_type("flex-grow", "NonNegativeNumber",
+                          "From::from(0.0)",
                           spec="https://drafts.csswg.org/css-flexbox/#flex-grow-property",
                           extra_prefixes="webkit",
-                          animation_value_type="ComputedValue")}
+                          animation_value_type="NonNegativeNumber")}
 
-${helpers.predefined_type("flex-shrink", "Number",
-                          "1.0", "parse_non_negative",
+${helpers.predefined_type("flex-shrink", "NonNegativeNumber",
+                          "From::from(1.0)",
                           spec="https://drafts.csswg.org/css-flexbox/#flex-shrink-property",
                           extra_prefixes="webkit",
-                          animation_value_type="ComputedValue")}
+                          animation_value_type="NonNegativeNumber")}
 
 // https://drafts.csswg.org/css-align/#align-self-property
 % if product == "servo":
diff --git a/components/style/properties/longhand/xul.mako.rs b/components/style/properties/longhand/xul.mako.rs
index 5d9ec6623e2..6802f60460c 100644
--- a/components/style/properties/longhand/xul.mako.rs
+++ b/components/style/properties/longhand/xul.mako.rs
@@ -24,9 +24,9 @@ ${helpers.single_keyword("-moz-box-direction", "normal reverse",
                          alias="-webkit-box-direction",
                          spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/box-direction)")}
 
-${helpers.predefined_type("-moz-box-flex", "Number", "0.0", "parse_non_negative",
+${helpers.predefined_type("-moz-box-flex", "NonNegativeNumber", "From::from(0.)",
                           products="gecko", gecko_ffi_name="mBoxFlex",
-                          animation_value_type="ComputedValue",
+                          animation_value_type="NonNegativeNumber",
                           alias="-webkit-box-flex",
                           spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/box-flex)")}
 
diff --git a/components/style/properties/shorthand/position.mako.rs b/components/style/properties/shorthand/position.mako.rs
index c7653a48e15..acc98a990a3 100644
--- a/components/style/properties/shorthand/position.mako.rs
+++ b/components/style/properties/shorthand/position.mako.rs
@@ -46,12 +46,13 @@
                     extra_prefixes="webkit"
                     derive_serialize="True"
                     spec="https://drafts.csswg.org/css-flexbox/#flex-property">
-    use values::specified::Number;
+    use parser::Parse;
+    use values::specified::NonNegativeNumber;
 
     fn parse_flexibility<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                                 -> Result<(Number, Option<Number>),ParseError<'i>> {
-        let grow = Number::parse_non_negative(context, input)?;
-        let shrink = input.try(|i| Number::parse_non_negative(context, i)).ok();
+                                 -> Result<(NonNegativeNumber, Option<NonNegativeNumber>),ParseError<'i>> {
+        let grow = NonNegativeNumber::parse(context, input)?;
+        let shrink = input.try(|i| NonNegativeNumber::parse(context, i)).ok();
         Ok((grow, shrink))
     }
 
@@ -63,8 +64,8 @@
 
         if input.try(|input| input.expect_ident_matching("none")).is_ok() {
             return Ok(expanded! {
-                flex_grow: Number::new(0.0),
-                flex_shrink: Number::new(0.0),
+                flex_grow: NonNegativeNumber::new(0.0),
+                flex_shrink: NonNegativeNumber::new(0.0),
                 flex_basis: longhands::flex_basis::SpecifiedValue::auto(),
             })
         }
@@ -89,8 +90,8 @@
             return Err(StyleParseError::UnspecifiedError.into())
         }
         Ok(expanded! {
-            flex_grow: grow.unwrap_or(Number::new(1.0)),
-            flex_shrink: shrink.unwrap_or(Number::new(1.0)),
+            flex_grow: grow.unwrap_or(NonNegativeNumber::new(1.0)),
+            flex_shrink: shrink.unwrap_or(NonNegativeNumber::new(1.0)),
             // Per spec, this should be SpecifiedValue::zero(), but all
             // browsers currently agree on using `0%`. This is a spec
             // change which hasn't been adopted by browsers:
diff --git a/components/style/values/animated/mod.rs b/components/style/values/animated/mod.rs
index 63d85254598..d6a4acea1b0 100644
--- a/components/style/values/animated/mod.rs
+++ b/components/style/values/animated/mod.rs
@@ -10,6 +10,8 @@
 
 use app_units::Au;
 use values::computed::Angle as ComputedAngle;
+use values::computed::GreaterThanOrEqualToOneNumber as ComputedGreaterThanOrEqualToOneNumber;
+use values::computed::NonNegativeNumber as ComputedNonNegativeNumber;
 use values::specified::url::SpecifiedUrl;
 
 pub mod effects;
@@ -88,6 +90,34 @@ where
     }
 }
 
+impl ToAnimatedValue for ComputedNonNegativeNumber {
+    type AnimatedValue = Self;
+
+    #[inline]
+    fn to_animated_value(self) -> Self {
+        self
+    }
+
+    #[inline]
+    fn from_animated_value(animated: Self::AnimatedValue) -> Self {
+        animated.0.max(0.).into()
+    }
+}
+
+impl ToAnimatedValue for ComputedGreaterThanOrEqualToOneNumber {
+    type AnimatedValue = Self;
+
+    #[inline]
+    fn to_animated_value(self) -> Self {
+        self
+    }
+
+    #[inline]
+    fn from_animated_value(animated: Self::AnimatedValue) -> Self {
+        animated.0.max(1.).into()
+    }
+}
+
 /// Returns a value similar to `self` that represents zero.
 pub trait ToAnimatedZero: Sized {
     /// Returns a value that, when added with an underlying value, will produce the underlying
diff --git a/components/style/values/computed/mod.rs b/components/style/values/computed/mod.rs
index d2b49ef5e22..f492279a559 100644
--- a/components/style/values/computed/mod.rs
+++ b/components/style/values/computed/mod.rs
@@ -18,6 +18,7 @@ use std::f64::consts::PI;
 use std::fmt;
 use style_traits::ToCss;
 use super::{CSSFloat, CSSInteger};
+use super::generics::{GreaterThanOrEqualToOne, NonNegative};
 use super::generics::grid::{TrackBreadth as GenericTrackBreadth, TrackSize as GenericTrackSize};
 use super::generics::grid::GridTemplateComponent as GenericGridTemplateComponent;
 use super::generics::grid::TrackList as GenericTrackList;
@@ -425,6 +426,40 @@ impl ComputedValueAsSpecified for specified::BorderStyle {}
 /// A `<number>` value.
 pub type Number = CSSFloat;
 
+/// A wrapper of Number, but the value >= 0.
+pub type NonNegativeNumber = NonNegative<CSSFloat>;
+
+impl From<CSSFloat> for NonNegativeNumber {
+    #[inline]
+    fn from(number: CSSFloat) -> NonNegativeNumber {
+        NonNegative::<CSSFloat>(number)
+    }
+}
+
+impl From<NonNegativeNumber> for CSSFloat {
+    #[inline]
+    fn from(number: NonNegativeNumber) -> CSSFloat {
+        number.0
+    }
+}
+
+/// A wrapper of Number, but the value >= 1.
+pub type GreaterThanOrEqualToOneNumber = GreaterThanOrEqualToOne<CSSFloat>;
+
+impl From<CSSFloat> for GreaterThanOrEqualToOneNumber {
+    #[inline]
+    fn from(number: CSSFloat) -> GreaterThanOrEqualToOneNumber {
+        GreaterThanOrEqualToOne::<CSSFloat>(number)
+    }
+}
+
+impl From<GreaterThanOrEqualToOneNumber> for CSSFloat {
+    #[inline]
+    fn from(number: GreaterThanOrEqualToOneNumber) -> CSSFloat {
+        number.0
+    }
+}
+
 #[allow(missing_docs)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
 #[derive(Clone, Copy, Debug, PartialEq, ToCss)]
diff --git a/components/style/values/generics/mod.rs b/components/style/values/generics/mod.rs
index 9456f0061c5..f87b7a88de5 100644
--- a/components/style/values/generics/mod.rs
+++ b/components/style/values/generics/mod.rs
@@ -252,3 +252,13 @@ impl ToCss for FontSettingTagFloat {
         self.0.to_css(dest)
     }
 }
+
+/// A wrapper of Non-negative values.
+#[derive(Clone, Copy, Debug, HasViewportPercentage, PartialEq, PartialOrd, ToComputedValue, ToCss)]
+#[cfg_attr(feature = "servo", derive(HeapSizeOf, Deserialize, Serialize))]
+pub struct NonNegative<T>(pub T);
+
+/// A wrapper of greater-than-or-equal-to-one values.
+#[derive(Clone, Copy, Debug, HasViewportPercentage, PartialEq, PartialOrd, ToComputedValue, ToCss)]
+#[cfg_attr(feature = "servo", derive(HeapSizeOf, Deserialize, Serialize))]
+pub struct GreaterThanOrEqualToOne<T>(pub T);
diff --git a/components/style/values/specified/mod.rs b/components/style/values/specified/mod.rs
index 1728d4113d4..11183126df1 100644
--- a/components/style/values/specified/mod.rs
+++ b/components/style/values/specified/mod.rs
@@ -18,6 +18,7 @@ use style_traits::{ToCss, ParseError, StyleParseError};
 use style_traits::values::specified::AllowedNumericType;
 use super::{Auto, CSSFloat, CSSInteger, Either, None_};
 use super::computed::{self, Context, ToComputedValue};
+use super::generics::{GreaterThanOrEqualToOne, NonNegative};
 use super::generics::grid::{TrackBreadth as GenericTrackBreadth, TrackSize as GenericTrackSize};
 use super::generics::grid::TrackList as GenericTrackList;
 use values::computed::ComputedValueAsSpecified;
@@ -509,6 +510,33 @@ impl ToCss for Number {
     }
 }
 
+/// A Number which is >= 0.0.
+pub type NonNegativeNumber = NonNegative<Number>;
+
+impl Parse for NonNegativeNumber {
+    fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
+        parse_number_with_clamping_mode(context, input, AllowedNumericType::NonNegative)
+            .map(NonNegative::<Number>)
+    }
+}
+
+impl NonNegativeNumber {
+    /// Returns a new non-negative number with the value `val`.
+    pub fn new(val: CSSFloat) -> Self {
+        NonNegative::<Number>(Number::new(val.max(0.)))
+    }
+}
+
+/// A Number which is >= 1.0.
+pub type GreaterThanOrEqualToOneNumber = GreaterThanOrEqualToOne<Number>;
+
+impl Parse for GreaterThanOrEqualToOneNumber {
+    fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
+        parse_number_with_clamping_mode(context, input, AllowedNumericType::AtLeastOne)
+            .map(GreaterThanOrEqualToOne::<Number>)
+    }
+}
+
 /// <number> | <percentage>
 ///
 /// Accepts only non-negative numbers.
diff --git a/tests/unit/style/properties/serialization.rs b/tests/unit/style/properties/serialization.rs
index 59013d1a01e..9e5f639f8e7 100644
--- a/tests/unit/style/properties/serialization.rs
+++ b/tests/unit/style/properties/serialization.rs
@@ -556,12 +556,12 @@ mod shorthand_serialization {
 
     #[test]
     fn flex_should_serialize_all_available_properties() {
-        use style::values::specified::{Number, Percentage};
+        use style::values::specified::{NonNegativeNumber, Percentage};
 
         let mut properties = Vec::new();
 
-        let grow = Number::new(2f32);
-        let shrink = Number::new(3f32);
+        let grow = NonNegativeNumber::new(2f32);
+        let shrink = NonNegativeNumber::new(3f32);
         let basis =
             FlexBasis::Length(Percentage::new(0.5f32).into());