servo/components/style/values/specified/ui.rs

/* 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/. */

//! Specified types for UI properties.

use cssparser::Parser;
use parser::{Parse, ParserContext};
use std::fmt::{self, Write};
use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};

/// Specified value of `-moz-force-broken-image-icon`
#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, ToComputedValue)]
pub struct MozForceBrokenImageIcon(pub bool);

impl MozForceBrokenImageIcon {
    /// Return initial value of -moz-force-broken-image-icon which is false.
    #[inline]
    pub fn false_value() -> MozForceBrokenImageIcon {
        MozForceBrokenImageIcon(false)
    }
}

impl Parse for MozForceBrokenImageIcon {
    fn parse<'i, 't>(
        _context: &ParserContext,
        input: &mut Parser<'i, 't>,
    ) -> Result<MozForceBrokenImageIcon, ParseError<'i>> {
        // We intentionally don't support calc values here.
        match input.expect_integer()? {
            0 => Ok(MozForceBrokenImageIcon(false)),
            1 => Ok(MozForceBrokenImageIcon(true)),
            _ => Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError)),
        }
    }
}

impl ToCss for MozForceBrokenImageIcon {
    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
    where
        W: Write,
    {
        dest.write_str(if self.0 { "1" } else { "0" })
    }
}

impl From<u8> for MozForceBrokenImageIcon {
    fn from(bits: u8) -> MozForceBrokenImageIcon {
        MozForceBrokenImageIcon(bits == 1)
    }
}

impl From<MozForceBrokenImageIcon> for u8 {
    fn from(v: MozForceBrokenImageIcon) -> u8 {
        if v.0 {
            1
        } else {
            0
        }
    }
}