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/* 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
//! Resolved values. These are almost always computed values, but in some cases
//! there are used values.
use crate::media_queries::Device;
use crate::properties::ComputedValues;
use crate::ArcSlice;
use servo_arc::Arc;
use smallvec::SmallVec;
mod color;
mod counters;
use crate::values::computed;
/// Element-specific information needed to resolve property values.
pub struct ResolvedElementInfo<'a> {
/// Element we're resolving line-height against.
#[cfg(feature = "gecko")]
pub element: crate::gecko::wrapper::GeckoElement<'a>,
}
/// Information needed to resolve a given value.
pub struct Context<'a> {
/// The style we're resolving for. This is useful to resolve currentColor.
pub style: &'a ComputedValues,
/// The device / document we're resolving style for. Useful to do font metrics stuff needed for
/// line-height.
pub device: &'a Device,
/// The element-specific information to resolve the value.
pub element_info: ResolvedElementInfo<'a>,
}
/// A trait to represent the conversion between resolved and resolved values.
///
/// This trait is derivable with `#[derive(ToResolvedValue)]`.
///
/// The deriving code assumes that if the type isn't generic, then the trait can
/// be implemented as simple move. This means that a manual implementation with
/// `ResolvedValue = Self` is bogus if it returns anything else than a clone.
pub trait ToResolvedValue {
/// The resolved value type we're going to be converted to.
type ResolvedValue;
/// Convert a resolved value to a resolved value.
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue;
/// Convert a resolved value to resolved value form.
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self;
}
macro_rules! trivial_to_resolved_value {
($ty:ty) => {
impl $crate::values::resolved::ToResolvedValue for $ty {
type ResolvedValue = Self;
#[inline]
fn to_resolved_value(self, _: &Context) -> Self {
self
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
resolved
}
}
};
}
trivial_to_resolved_value!(());
trivial_to_resolved_value!(bool);
trivial_to_resolved_value!(f32);
trivial_to_resolved_value!(u8);
trivial_to_resolved_value!(i8);
trivial_to_resolved_value!(u16);
trivial_to_resolved_value!(i16);
trivial_to_resolved_value!(u32);
trivial_to_resolved_value!(i32);
trivial_to_resolved_value!(usize);
trivial_to_resolved_value!(String);
trivial_to_resolved_value!(Box<str>);
trivial_to_resolved_value!(crate::OwnedStr);
trivial_to_resolved_value!(crate::color::AbsoluteColor);
trivial_to_resolved_value!(crate::values::generics::color::ColorMixFlags);
trivial_to_resolved_value!(crate::Atom);
trivial_to_resolved_value!(crate::values::AtomIdent);
trivial_to_resolved_value!(app_units::Au);
trivial_to_resolved_value!(computed::url::ComputedUrl);
#[cfg(feature = "gecko")]
trivial_to_resolved_value!(computed::url::ComputedImageUrl);
#[cfg(feature = "servo")]
trivial_to_resolved_value!(crate::Namespace);
#[cfg(feature = "servo")]
trivial_to_resolved_value!(crate::Prefix);
trivial_to_resolved_value!(style_traits::values::specified::AllowedNumericType);
trivial_to_resolved_value!(computed::TimingFunction);
impl<A, B> ToResolvedValue for (A, B)
where
A: ToResolvedValue,
B: ToResolvedValue,
{
type ResolvedValue = (
<A as ToResolvedValue>::ResolvedValue,
<B as ToResolvedValue>::ResolvedValue,
);
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
(
self.0.to_resolved_value(context),
self.1.to_resolved_value(context),
)
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
(
A::from_resolved_value(resolved.0),
B::from_resolved_value(resolved.1),
)
}
}
impl<T> ToResolvedValue for Option<T>
where
T: ToResolvedValue,
{
type ResolvedValue = Option<<T as ToResolvedValue>::ResolvedValue>;
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
self.map(|item| item.to_resolved_value(context))
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
resolved.map(T::from_resolved_value)
}
}
impl<T> ToResolvedValue for SmallVec<[T; 1]>
where
T: ToResolvedValue,
{
type ResolvedValue = SmallVec<[<T as ToResolvedValue>::ResolvedValue; 1]>;
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
self.into_iter()
.map(|item| item.to_resolved_value(context))
.collect()
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
resolved.into_iter().map(T::from_resolved_value).collect()
}
}
impl<T> ToResolvedValue for Vec<T>
where
T: ToResolvedValue,
{
type ResolvedValue = Vec<<T as ToResolvedValue>::ResolvedValue>;
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
self.into_iter()
.map(|item| item.to_resolved_value(context))
.collect()
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
resolved.into_iter().map(T::from_resolved_value).collect()
}
}
impl<T> ToResolvedValue for Box<T>
where
T: ToResolvedValue,
{
type ResolvedValue = Box<<T as ToResolvedValue>::ResolvedValue>;
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
Box::new(T::to_resolved_value(*self, context))
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
Box::new(T::from_resolved_value(*resolved))
}
}
impl<T> ToResolvedValue for Box<[T]>
where
T: ToResolvedValue,
{
type ResolvedValue = Box<[<T as ToResolvedValue>::ResolvedValue]>;
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
Vec::from(self)
.to_resolved_value(context)
.into_boxed_slice()
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
Vec::from_resolved_value(Vec::from(resolved)).into_boxed_slice()
}
}
impl<T> ToResolvedValue for crate::OwnedSlice<T>
where
T: ToResolvedValue,
{
type ResolvedValue = crate::OwnedSlice<<T as ToResolvedValue>::ResolvedValue>;
#[inline]
fn to_resolved_value(self, context: &Context) -> Self::ResolvedValue {
self.into_box().to_resolved_value(context).into()
}
#[inline]
fn from_resolved_value(resolved: Self::ResolvedValue) -> Self {
Self::from(Box::from_resolved_value(resolved.into_box()))
}
}
// NOTE(emilio): This is implementable more generically, but it's unlikely what
// you want there, as it forces you to have an extra allocation.
//
// We could do that if needed, ideally with specialization for the case where
// ResolvedValue = T. But we don't need it for now.
impl<T> ToResolvedValue for Arc<T>
where
T: ToResolvedValue<ResolvedValue = T>,
{
type ResolvedValue = Self;
#[inline]
fn to_resolved_value(self, _: &Context) -> Self {
self
}
#[inline]
fn from_resolved_value(resolved: Self) -> Self {
resolved
}
}
// Same caveat as above applies.
impl<T> ToResolvedValue for ArcSlice<T>
where
T: ToResolvedValue<ResolvedValue = T>,
{
type ResolvedValue = Self;
#[inline]
fn to_resolved_value(self, _: &Context) -> Self {
self
}
#[inline]
fn from_resolved_value(resolved: Self) -> Self {
resolved
}
}