servo/components/style/properties/shorthand/background.mako.rs
2018-04-02 19:34:58 +02:00

253 lines
11 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/. */
<%namespace name="helpers" file="/helpers.mako.rs" />
// TODO: other background-* properties
<%helpers:shorthand name="background"
sub_properties="background-color background-position-x background-position-y background-repeat
background-attachment background-image background-size background-origin
background-clip"
spec="https://drafts.csswg.org/css-backgrounds/#the-background">
use properties::longhands::{background_position_x, background_position_y, background_repeat};
use properties::longhands::{background_attachment, background_image, background_size, background_origin};
use properties::longhands::background_clip;
use properties::longhands::background_clip::single_value::computed_value::T as Clip;
use properties::longhands::background_origin::single_value::computed_value::T as Origin;
use values::specified::{Color, Position, PositionComponent};
use parser::Parse;
// FIXME(emilio): Should be the same type!
impl From<background_origin::single_value::SpecifiedValue> for background_clip::single_value::SpecifiedValue {
fn from(origin: background_origin::single_value::SpecifiedValue) ->
background_clip::single_value::SpecifiedValue {
match origin {
background_origin::single_value::SpecifiedValue::ContentBox =>
background_clip::single_value::SpecifiedValue::ContentBox,
background_origin::single_value::SpecifiedValue::PaddingBox =>
background_clip::single_value::SpecifiedValue::PaddingBox,
background_origin::single_value::SpecifiedValue::BorderBox =>
background_clip::single_value::SpecifiedValue::BorderBox,
}
}
}
pub fn parse_value<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Longhands, ParseError<'i>> {
let mut background_color = None;
% for name in "image position_x position_y repeat size attachment origin clip".split():
// Vec grows from 0 to 4 by default on first push(). So allocate
// with capacity 1, so in the common case of only one item we don't
// way overallocate. Note that we always push at least one item if
// parsing succeeds.
let mut background_${name} = background_${name}::SpecifiedValue(Vec::with_capacity(1));
% endfor
input.parse_comma_separated(|input| {
// background-color can only be in the last element, so if it
// is parsed anywhere before, the value is invalid.
if background_color.is_some() {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
% for name in "image position repeat size attachment origin clip".split():
let mut ${name} = None;
% endfor
loop {
if background_color.is_none() {
if let Ok(value) = input.try(|i| Color::parse(context, i)) {
background_color = Some(value);
continue
}
}
if position.is_none() {
if let Ok(value) = input.try(|input| Position::parse(context, input)) {
position = Some(value);
// Parse background size, if applicable.
size = input.try(|input| {
input.expect_delim('/')?;
background_size::single_value::parse(context, input)
}).ok();
continue
}
}
% for name in "image repeat attachment origin clip".split():
if ${name}.is_none() {
if let Ok(value) = input.try(|input| background_${name}::single_value
::parse(context, input)) {
${name} = Some(value);
continue
}
}
% endfor
break
}
if clip.is_none() {
if let Some(origin) = origin {
clip = Some(background_clip::single_value::SpecifiedValue::from(origin));
}
}
let mut any = false;
% for name in "image position repeat size attachment origin clip".split():
any = any || ${name}.is_some();
% endfor
any = any || background_color.is_some();
if any {
if let Some(position) = position {
background_position_x.0.push(position.horizontal);
background_position_y.0.push(position.vertical);
} else {
background_position_x.0.push(PositionComponent::zero());
background_position_y.0.push(PositionComponent::zero());
}
% for name in "image repeat size attachment origin clip".split():
if let Some(bg_${name}) = ${name} {
background_${name}.0.push(bg_${name});
} else {
background_${name}.0.push(background_${name}::single_value
::get_initial_specified_value());
}
% endfor
Ok(())
} else {
Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
}
})?;
Ok(expanded! {
background_color: background_color.unwrap_or(Color::transparent()),
background_image: background_image,
background_position_x: background_position_x,
background_position_y: background_position_y,
background_repeat: background_repeat,
background_attachment: background_attachment,
background_size: background_size,
background_origin: background_origin,
background_clip: background_clip,
})
}
impl<'a> ToCss for LonghandsToSerialize<'a> {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
let len = self.background_image.0.len();
// There should be at least one declared value
if len == 0 {
return Ok(());
}
// If a value list length is differs then we don't do a shorthand serialization.
// The exceptions to this is color which appears once only and is serialized
// with the last item.
% for name in "image position_x position_y size repeat origin clip attachment".split():
if len != self.background_${name}.0.len() {
return Ok(());
}
% endfor
for i in 0..len {
% for name in "image position_x position_y repeat size attachment origin clip".split():
let ${name} = &self.background_${name}.0[i];
% endfor
if i != 0 {
dest.write_str(", ")?;
}
if i == len - 1 {
self.background_color.to_css(dest)?;
dest.write_str(" ")?;
}
image.to_css(dest)?;
% for name in "repeat attachment".split():
dest.write_str(" ")?;
${name}.to_css(dest)?;
% endfor
dest.write_str(" ")?;
Position {
horizontal: position_x.clone(),
vertical: position_y.clone()
}.to_css(dest)?;
if *size != background_size::single_value::get_initial_specified_value() {
dest.write_str(" / ")?;
size.to_css(dest)?;
}
if *origin != Origin::PaddingBox || *clip != Clip::BorderBox {
dest.write_str(" ")?;
origin.to_css(dest)?;
if *clip != From::from(*origin) {
dest.write_str(" ")?;
clip.to_css(dest)?;
}
}
}
Ok(())
}
}
</%helpers:shorthand>
<%helpers:shorthand name="background-position"
sub_properties="background-position-x background-position-y"
spec="https://drafts.csswg.org/css-backgrounds-4/#the-background-position">
use properties::longhands::{background_position_x, background_position_y};
use values::specified::AllowQuirks;
use values::specified::position::Position;
pub fn parse_value<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Longhands, ParseError<'i>> {
// Vec grows from 0 to 4 by default on first push(). So allocate with
// capacity 1, so in the common case of only one item we don't way
// overallocate. Note that we always push at least one item if parsing
// succeeds.
let mut position_x = background_position_x::SpecifiedValue(Vec::with_capacity(1));
let mut position_y = background_position_y::SpecifiedValue(Vec::with_capacity(1));
let mut any = false;
input.parse_comma_separated(|input| {
let value = Position::parse_quirky(context, input, AllowQuirks::Yes)?;
position_x.0.push(value.horizontal);
position_y.0.push(value.vertical);
any = true;
Ok(())
})?;
if !any {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok(expanded! {
background_position_x: position_x,
background_position_y: position_y,
})
}
impl<'a> ToCss for LonghandsToSerialize<'a> {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
let len = self.background_position_x.0.len();
if len == 0 || len != self.background_position_y.0.len() {
return Ok(());
}
for i in 0..len {
Position {
horizontal: self.background_position_x.0[i].clone(),
vertical: self.background_position_y.0[i].clone()
}.to_css(dest)?;
if i < len - 1 {
dest.write_str(", ")?;
}
}
Ok(())
}
}
</%helpers:shorthand>