servo/components/style/values/computed/text.rs
2017-10-27 23:09:05 -05:00

76 lines
2.5 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 http://mozilla.org/MPL/2.0/. */
//! Computed types for text properties.
use std::fmt;
use style_traits::ToCss;
use values::{CSSInteger, CSSFloat};
use values::animated::ToAnimatedZero;
use values::computed::{NonNegativeLength, NonNegativeNumber};
use values::computed::length::{Length, LengthOrPercentage};
use values::generics::text::InitialLetter as GenericInitialLetter;
use values::generics::text::LineHeight as GenericLineHeight;
use values::generics::text::Spacing;
use values::specified::text::TextOverflowSide;
/// A computed value for the `initial-letter` property.
pub type InitialLetter = GenericInitialLetter<CSSFloat, CSSInteger>;
/// A computed value for the `letter-spacing` property.
pub type LetterSpacing = Spacing<Length>;
/// A computed value for the `word-spacing` property.
pub type WordSpacing = Spacing<LengthOrPercentage>;
/// A computed value for the `line-height` property.
pub type LineHeight = GenericLineHeight<NonNegativeNumber, NonNegativeLength>;
impl ToAnimatedZero for LineHeight {
#[inline]
fn to_animated_zero(&self) -> Result<Self, ()> { Err(()) }
}
#[derive(Clone, Debug, MallocSizeOf, PartialEq)]
/// text-overflow.
/// When the specified value only has one side, that's the "second"
/// side, and the sides are logical, so "second" means "end". The
/// start side is Clip in that case.
///
/// When the specified value has two sides, those are our "first"
/// and "second" sides, and they are physical sides ("left" and
/// "right").
pub struct TextOverflow {
/// First side
pub first: TextOverflowSide,
/// Second side
pub second: TextOverflowSide,
/// True if the specified value only has one side.
pub sides_are_logical: bool,
}
impl TextOverflow {
/// Returns the initial `text-overflow` value
pub fn get_initial_value() -> TextOverflow {
TextOverflow {
first: TextOverflowSide::Clip,
second: TextOverflowSide::Clip,
sides_are_logical: true,
}
}
}
impl ToCss for TextOverflow {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
if self.sides_are_logical {
debug_assert!(self.first == TextOverflowSide::Clip);
self.second.to_css(dest)?;
} else {
self.first.to_css(dest)?;
dest.write_str(" ")?;
self.second.to_css(dest)?;
}
Ok(())
}
}