servo/components/style/values/generics/background.rs
2019-04-12 12:19:52 +02:00

63 lines
1.8 KiB
Rust

/* 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 https://mozilla.org/MPL/2.0/. */
//! Generic types for CSS values related to backgrounds.
use crate::values::generics::length::{GenericLengthPercentageOrAuto, LengthPercentageOrAuto};
fn width_and_height_are_auto<L>(
width: &LengthPercentageOrAuto<L>,
height: &LengthPercentageOrAuto<L>,
) -> bool {
width.is_auto() && height.is_auto()
}
/// A generic value for the `background-size` property.
#[derive(
Animate,
Clone,
ComputeSquaredDistance,
Copy,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToAnimatedValue,
ToAnimatedZero,
ToComputedValue,
ToCss,
ToShmem,
)]
#[repr(C, u8)]
pub enum GenericBackgroundSize<LengthPercent> {
/// `<width> <height>`
ExplicitSize {
/// Explicit width.
width: GenericLengthPercentageOrAuto<LengthPercent>,
/// Explicit height.
/// NOTE(emilio): We should probably simplify all these in case `width`
/// and `height` are the same, but all other browsers agree on only
/// special-casing `auto`.
#[css(contextual_skip_if = "width_and_height_are_auto")]
height: GenericLengthPercentageOrAuto<LengthPercent>,
},
/// `cover`
#[animation(error)]
Cover,
/// `contain`
#[animation(error)]
Contain,
}
pub use self::GenericBackgroundSize as BackgroundSize;
impl<LengthPercentage> BackgroundSize<LengthPercentage> {
/// Returns `auto auto`.
pub fn auto() -> Self {
GenericBackgroundSize::ExplicitSize {
width: LengthPercentageOrAuto::Auto,
height: LengthPercentageOrAuto::Auto,
}
}
}