Source code
Revision control
Copy as Markdown
Other Tools
/* 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
//! CSS handling for the specified value of
//! [`image`][image]s
//!
use crate::color::mix::ColorInterpolationMethod;
use crate::parser::{Parse, ParserContext};
use crate::stylesheets::CorsMode;
use crate::values::generics::color::ColorMixFlags;
use crate::values::generics::image::{
self as generic, Circle, Ellipse, GradientCompatMode, ShapeExtent,
};
use crate::values::generics::image::{GradientFlags, PaintWorklet};
use crate::values::generics::position::Position as GenericPosition;
use crate::values::generics::NonNegative;
use crate::values::specified::position::{HorizontalPositionKeyword, VerticalPositionKeyword};
use crate::values::specified::position::{Position, PositionComponent, Side};
use crate::values::specified::url::SpecifiedImageUrl;
use crate::values::specified::{
Angle, AngleOrPercentage, Color, Length, LengthPercentage, NonNegativeLength,
NonNegativeLengthPercentage, Resolution,
};
use crate::values::specified::{Number, NumberOrPercentage, Percentage};
use crate::Atom;
use cssparser::{Delimiter, Parser, Token};
use selectors::parser::SelectorParseErrorKind;
use std::cmp::Ordering;
use std::fmt::{self, Write};
use style_traits::{CssType, CssWriter, KeywordsCollectFn, ParseError};
use style_traits::{SpecifiedValueInfo, StyleParseErrorKind, ToCss};
#[inline]
fn gradient_color_interpolation_method_enabled() -> bool {
static_prefs::pref!("layout.css.gradient-color-interpolation-method.enabled")
}
/// Specified values for an image according to CSS-IMAGES.
pub type Image = generic::Image<Gradient, SpecifiedImageUrl, Color, Percentage, Resolution>;
size_of_test!(Image, 16);
/// Specified values for a CSS gradient.
pub type Gradient = generic::Gradient<
LineDirection,
LengthPercentage,
NonNegativeLength,
NonNegativeLengthPercentage,
Position,
Angle,
AngleOrPercentage,
Color,
>;
/// Specified values for CSS cross-fade
/// cross-fade( CrossFadeElement, ...)
pub type CrossFade = generic::CrossFade<Image, Color, Percentage>;
/// CrossFadeElement = percent? CrossFadeImage
pub type CrossFadeElement = generic::CrossFadeElement<Image, Color, Percentage>;
/// CrossFadeImage = image | color
pub type CrossFadeImage = generic::CrossFadeImage<Image, Color>;
/// `image-set()`
pub type ImageSet = generic::ImageSet<Image, Resolution>;
/// Each of the arguments to `image-set()`
pub type ImageSetItem = generic::ImageSetItem<Image, Resolution>;
type LengthPercentageItemList = crate::OwnedSlice<generic::GradientItem<Color, LengthPercentage>>;
impl Color {
fn has_modern_syntax(&self) -> bool {
match self {
Self::Absolute(absolute) => !absolute.color.is_legacy_syntax(),
Self::ColorMix(mix) => {
if mix.flags.contains(ColorMixFlags::RESULT_IN_MODERN_SYNTAX) {
true
} else {
mix.left.has_modern_syntax() || mix.right.has_modern_syntax()
}
},
Self::LightDark(ld) => ld.light.has_modern_syntax() || ld.dark.has_modern_syntax(),
// The default is that this color doesn't have any modern syntax.
_ => false,
}
}
}
fn default_color_interpolation_method<T>(
items: &[generic::GradientItem<Color, T>],
) -> ColorInterpolationMethod {
let has_modern_syntax_item = items.iter().any(|item| match item {
generic::GenericGradientItem::SimpleColorStop(color) => color.has_modern_syntax(),
generic::GenericGradientItem::ComplexColorStop { color, .. } => color.has_modern_syntax(),
generic::GenericGradientItem::InterpolationHint(_) => false,
});
if has_modern_syntax_item {
ColorInterpolationMethod::oklab()
} else {
ColorInterpolationMethod::srgb()
}
}
#[cfg(feature = "gecko")]
fn cross_fade_enabled() -> bool {
static_prefs::pref!("layout.css.cross-fade.enabled")
}
#[cfg(feature = "servo")]
fn cross_fade_enabled() -> bool {
false
}
impl SpecifiedValueInfo for Gradient {
const SUPPORTED_TYPES: u8 = CssType::GRADIENT;
fn collect_completion_keywords(f: KeywordsCollectFn) {
// This list here should keep sync with that in Gradient::parse.
f(&[
"linear-gradient",
"-webkit-linear-gradient",
"-moz-linear-gradient",
"repeating-linear-gradient",
"-webkit-repeating-linear-gradient",
"-moz-repeating-linear-gradient",
"radial-gradient",
"-webkit-radial-gradient",
"-moz-radial-gradient",
"repeating-radial-gradient",
"-webkit-repeating-radial-gradient",
"-moz-repeating-radial-gradient",
"-webkit-gradient",
"conic-gradient",
"repeating-conic-gradient",
]);
}
}
// Need to manually implement as whether or not cross-fade shows up in
// completions & etc is dependent on it being enabled.
impl<Image, Color, Percentage> SpecifiedValueInfo for generic::CrossFade<Image, Color, Percentage> {
const SUPPORTED_TYPES: u8 = 0;
fn collect_completion_keywords(f: KeywordsCollectFn) {
if cross_fade_enabled() {
f(&["cross-fade"]);
}
}
}
impl<Image, Resolution> SpecifiedValueInfo for generic::ImageSet<Image, Resolution> {
const SUPPORTED_TYPES: u8 = 0;
fn collect_completion_keywords(f: KeywordsCollectFn) {
f(&["image-set"]);
}
}
/// A specified gradient line direction.
///
/// FIXME(emilio): This should be generic over Angle.
#[derive(Clone, Debug, MallocSizeOf, PartialEq, ToShmem)]
pub enum LineDirection {
/// An angular direction.
Angle(Angle),
/// A horizontal direction.
Horizontal(HorizontalPositionKeyword),
/// A vertical direction.
Vertical(VerticalPositionKeyword),
/// A direction towards a corner of a box.
Corner(HorizontalPositionKeyword, VerticalPositionKeyword),
}
/// A specified ending shape.
pub type EndingShape = generic::EndingShape<NonNegativeLength, NonNegativeLengthPercentage>;
bitflags! {
#[derive(Clone, Copy)]
struct ParseImageFlags: u8 {
const FORBID_NONE = 1 << 0;
const FORBID_IMAGE_SET = 1 << 1;
const FORBID_NON_URL = 1 << 2;
}
}
impl Parse for Image {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Image, ParseError<'i>> {
Image::parse_with_cors_mode(context, input, CorsMode::None, ParseImageFlags::empty())
}
}
impl Image {
fn parse_with_cors_mode<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
cors_mode: CorsMode,
flags: ParseImageFlags,
) -> Result<Image, ParseError<'i>> {
if !flags.contains(ParseImageFlags::FORBID_NONE) &&
input.try_parse(|i| i.expect_ident_matching("none")).is_ok()
{
return Ok(generic::Image::None);
}
if let Ok(url) = input
.try_parse(|input| SpecifiedImageUrl::parse_with_cors_mode(context, input, cors_mode))
{
return Ok(generic::Image::Url(url));
}
if !flags.contains(ParseImageFlags::FORBID_IMAGE_SET) {
if let Ok(is) =
input.try_parse(|input| ImageSet::parse(context, input, cors_mode, flags))
{
return Ok(generic::Image::ImageSet(Box::new(is)));
}
}
if flags.contains(ParseImageFlags::FORBID_NON_URL) {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
if let Ok(gradient) = input.try_parse(|i| Gradient::parse(context, i)) {
return Ok(generic::Image::Gradient(Box::new(gradient)));
}
let function = input.expect_function()?.clone();
input.parse_nested_block(|input| {
Ok(match_ignore_ascii_case! { &function,
#[cfg(feature = "servo")]
"paint" => Self::PaintWorklet(PaintWorklet::parse_args(context, input)?),
"cross-fade" if cross_fade_enabled() => Self::CrossFade(Box::new(CrossFade::parse_args(context, input, cors_mode, flags)?)),
#[cfg(feature = "gecko")]
"-moz-element" => Self::Element(Self::parse_element(input)?),
_ => return Err(input.new_custom_error(StyleParseErrorKind::UnexpectedFunction(function))),
})
})
}
}
impl Image {
/// Creates an already specified image value from an already resolved URL
/// for insertion in the cascade.
#[cfg(feature = "servo")]
pub fn for_cascade(url: ::servo_arc::Arc<::url::Url>) -> Self {
use crate::values::CssUrl;
generic::Image::Url(CssUrl::for_cascade(url))
}
/// Parses a `-moz-element(# <element-id>)`.
#[cfg(feature = "gecko")]
fn parse_element<'i>(input: &mut Parser<'i, '_>) -> Result<Atom, ParseError<'i>> {
let location = input.current_source_location();
Ok(match *input.next()? {
Token::IDHash(ref id) => Atom::from(id.as_ref()),
ref t => return Err(location.new_unexpected_token_error(t.clone())),
})
}
/// Provides an alternate method for parsing that associates the URL with
/// anonymous CORS headers.
pub fn parse_with_cors_anonymous<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Image, ParseError<'i>> {
Self::parse_with_cors_mode(
context,
input,
CorsMode::Anonymous,
ParseImageFlags::empty(),
)
}
/// Provides an alternate method for parsing, but forbidding `none`
pub fn parse_forbid_none<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Image, ParseError<'i>> {
Self::parse_with_cors_mode(context, input, CorsMode::None, ParseImageFlags::FORBID_NONE)
}
/// Provides an alternate method for parsing, but only for urls.
pub fn parse_only_url<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Image, ParseError<'i>> {
Self::parse_with_cors_mode(
context,
input,
CorsMode::None,
ParseImageFlags::FORBID_NONE | ParseImageFlags::FORBID_NON_URL,
)
}
}
impl CrossFade {
/// cross-fade() = cross-fade( <cf-image># )
fn parse_args<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
cors_mode: CorsMode,
flags: ParseImageFlags,
) -> Result<Self, ParseError<'i>> {
let elements = crate::OwnedSlice::from(input.parse_comma_separated(|input| {
CrossFadeElement::parse(context, input, cors_mode, flags)
})?);
Ok(Self { elements })
}
}
impl CrossFadeElement {
fn parse_percentage<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Option<Percentage> {
// We clamp our values here as this is the way that Safari and Chrome's
// implementation handle out-of-bounds percentages but whether or not
// this behavior follows the specification is still being discussed.
input
.try_parse(|input| Percentage::parse_non_negative(context, input))
.ok()
.map(|p| p.clamp_to_hundred())
}
/// <cf-image> = <percentage>? && [ <image> | <color> ]
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
cors_mode: CorsMode,
flags: ParseImageFlags,
) -> Result<Self, ParseError<'i>> {
// Try and parse a leading percent sign.
let mut percent = Self::parse_percentage(context, input);
// Parse the image
let image = CrossFadeImage::parse(context, input, cors_mode, flags)?;
// Try and parse a trailing percent sign.
if percent.is_none() {
percent = Self::parse_percentage(context, input);
}
Ok(Self {
percent: percent.into(),
image,
})
}
}
impl CrossFadeImage {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
cors_mode: CorsMode,
flags: ParseImageFlags,
) -> Result<Self, ParseError<'i>> {
if let Ok(image) = input.try_parse(|input| {
Image::parse_with_cors_mode(
context,
input,
cors_mode,
flags | ParseImageFlags::FORBID_NONE,
)
}) {
return Ok(Self::Image(image));
}
Ok(Self::Color(Color::parse(context, input)?))
}
}
impl ImageSet {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
cors_mode: CorsMode,
flags: ParseImageFlags,
) -> Result<Self, ParseError<'i>> {
let function = input.expect_function()?;
match_ignore_ascii_case! { &function,
"-webkit-image-set" | "image-set" => {},
_ => {
let func = function.clone();
return Err(input.new_custom_error(StyleParseErrorKind::UnexpectedFunction(func)));
}
}
let items = input.parse_nested_block(|input| {
input.parse_comma_separated(|input| {
ImageSetItem::parse(context, input, cors_mode, flags)
})
})?;
Ok(Self {
selected_index: std::usize::MAX,
items: items.into(),
})
}
}
impl ImageSetItem {
fn parse_type<'i>(p: &mut Parser<'i, '_>) -> Result<crate::OwnedStr, ParseError<'i>> {
p.expect_function_matching("type")?;
p.parse_nested_block(|input| Ok(input.expect_string()?.as_ref().to_owned().into()))
}
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
cors_mode: CorsMode,
flags: ParseImageFlags,
) -> Result<Self, ParseError<'i>> {
let image = match input.try_parse(|i| i.expect_url_or_string()) {
Ok(url) => Image::Url(SpecifiedImageUrl::parse_from_string(
url.as_ref().into(),
context,
cors_mode,
)),
Err(..) => Image::parse_with_cors_mode(
context,
input,
cors_mode,
flags | ParseImageFlags::FORBID_NONE | ParseImageFlags::FORBID_IMAGE_SET,
)?,
};
let mut resolution = input
.try_parse(|input| Resolution::parse(context, input))
.ok();
let mime_type = input.try_parse(Self::parse_type).ok();
// Try to parse resolution after type().
if mime_type.is_some() && resolution.is_none() {
resolution = input
.try_parse(|input| Resolution::parse(context, input))
.ok();
}
let resolution = resolution.unwrap_or_else(|| Resolution::from_x(1.0));
let has_mime_type = mime_type.is_some();
let mime_type = mime_type.unwrap_or_default();
Ok(Self {
image,
resolution,
has_mime_type,
mime_type,
})
}
}
impl Parse for Gradient {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
enum Shape {
Linear,
Radial,
Conic,
}
let func = input.expect_function()?;
let (shape, repeating, compat_mode) = match_ignore_ascii_case! { &func,
"linear-gradient" => {
(Shape::Linear, false, GradientCompatMode::Modern)
},
"-webkit-linear-gradient" => {
(Shape::Linear, false, GradientCompatMode::WebKit)
},
#[cfg(feature = "gecko")]
"-moz-linear-gradient" => {
(Shape::Linear, false, GradientCompatMode::Moz)
},
"repeating-linear-gradient" => {
(Shape::Linear, true, GradientCompatMode::Modern)
},
"-webkit-repeating-linear-gradient" => {
(Shape::Linear, true, GradientCompatMode::WebKit)
},
#[cfg(feature = "gecko")]
"-moz-repeating-linear-gradient" => {
(Shape::Linear, true, GradientCompatMode::Moz)
},
"radial-gradient" => {
(Shape::Radial, false, GradientCompatMode::Modern)
},
"-webkit-radial-gradient" => {
(Shape::Radial, false, GradientCompatMode::WebKit)
},
#[cfg(feature = "gecko")]
"-moz-radial-gradient" => {
(Shape::Radial, false, GradientCompatMode::Moz)
},
"repeating-radial-gradient" => {
(Shape::Radial, true, GradientCompatMode::Modern)
},
"-webkit-repeating-radial-gradient" => {
(Shape::Radial, true, GradientCompatMode::WebKit)
},
#[cfg(feature = "gecko")]
"-moz-repeating-radial-gradient" => {
(Shape::Radial, true, GradientCompatMode::Moz)
},
"conic-gradient" => {
(Shape::Conic, false, GradientCompatMode::Modern)
},
"repeating-conic-gradient" => {
(Shape::Conic, true, GradientCompatMode::Modern)
},
"-webkit-gradient" => {
return input.parse_nested_block(|i| {
Self::parse_webkit_gradient_argument(context, i)
});
},
_ => {
let func = func.clone();
return Err(input.new_custom_error(StyleParseErrorKind::UnexpectedFunction(func)));
}
};
Ok(input.parse_nested_block(|i| {
Ok(match shape {
Shape::Linear => Self::parse_linear(context, i, repeating, compat_mode)?,
Shape::Radial => Self::parse_radial(context, i, repeating, compat_mode)?,
Shape::Conic => Self::parse_conic(context, i, repeating)?,
})
})?)
}
}
impl Gradient {
fn parse_webkit_gradient_argument<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
use crate::values::specified::position::{
HorizontalPositionKeyword as X, VerticalPositionKeyword as Y,
};
type Point = GenericPosition<Component<X>, Component<Y>>;
#[derive(Clone, Copy, Parse)]
enum Component<S> {
Center,
Number(NumberOrPercentage),
Side(S),
}
fn line_direction_from_points(first: Point, second: Point) -> LineDirection {
let h_ord = first.horizontal.partial_cmp(&second.horizontal);
let v_ord = first.vertical.partial_cmp(&second.vertical);
let (h, v) = match (h_ord, v_ord) {
(Some(h), Some(v)) => (h, v),
_ => return LineDirection::Vertical(Y::Bottom),
};
match (h, v) {
(Ordering::Less, Ordering::Less) => LineDirection::Corner(X::Right, Y::Bottom),
(Ordering::Less, Ordering::Equal) => LineDirection::Horizontal(X::Right),
(Ordering::Less, Ordering::Greater) => LineDirection::Corner(X::Right, Y::Top),
(Ordering::Equal, Ordering::Greater) => LineDirection::Vertical(Y::Top),
(Ordering::Equal, Ordering::Equal) | (Ordering::Equal, Ordering::Less) => {
LineDirection::Vertical(Y::Bottom)
},
(Ordering::Greater, Ordering::Less) => LineDirection::Corner(X::Left, Y::Bottom),
(Ordering::Greater, Ordering::Equal) => LineDirection::Horizontal(X::Left),
(Ordering::Greater, Ordering::Greater) => LineDirection::Corner(X::Left, Y::Top),
}
}
impl Parse for Point {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
input.try_parse(|i| {
let x = Component::parse(context, i)?;
let y = Component::parse(context, i)?;
Ok(Self::new(x, y))
})
}
}
impl<S: Side> Into<NumberOrPercentage> for Component<S> {
fn into(self) -> NumberOrPercentage {
match self {
Component::Center => NumberOrPercentage::Percentage(Percentage::new(0.5)),
Component::Number(number) => number,
Component::Side(side) => {
let p = if side.is_start() {
Percentage::zero()
} else {
Percentage::hundred()
};
NumberOrPercentage::Percentage(p)
},
}
}
}
impl<S: Side> Into<PositionComponent<S>> for Component<S> {
fn into(self) -> PositionComponent<S> {
match self {
Component::Center => PositionComponent::Center,
Component::Number(NumberOrPercentage::Number(number)) => {
PositionComponent::Length(Length::from_px(number.value).into())
},
Component::Number(NumberOrPercentage::Percentage(p)) => {
PositionComponent::Length(p.into())
},
Component::Side(side) => PositionComponent::Side(side, None),
}
}
}
impl<S: Copy + Side> Component<S> {
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
match ((*self).into(), (*other).into()) {
(NumberOrPercentage::Percentage(a), NumberOrPercentage::Percentage(b)) => {
a.get().partial_cmp(&b.get())
},
(NumberOrPercentage::Number(a), NumberOrPercentage::Number(b)) => {
a.value.partial_cmp(&b.value)
},
(_, _) => None,
}
}
}
let ident = input.expect_ident_cloned()?;
input.expect_comma()?;
Ok(match_ignore_ascii_case! { &ident,
"linear" => {
let first = Point::parse(context, input)?;
input.expect_comma()?;
let second = Point::parse(context, input)?;
let direction = line_direction_from_points(first, second);
let items = Gradient::parse_webkit_gradient_stops(context, input, false)?;
generic::Gradient::Linear {
direction,
color_interpolation_method: ColorInterpolationMethod::srgb(),
items,
// Legacy gradients always use srgb as a default.
flags: generic::GradientFlags::HAS_DEFAULT_COLOR_INTERPOLATION_METHOD,
compat_mode: GradientCompatMode::Modern,
}
},
"radial" => {
let first_point = Point::parse(context, input)?;
input.expect_comma()?;
let first_radius = Number::parse_non_negative(context, input)?;
input.expect_comma()?;
let second_point = Point::parse(context, input)?;
input.expect_comma()?;
let second_radius = Number::parse_non_negative(context, input)?;
let (reverse_stops, point, radius) = if second_radius.value >= first_radius.value {
(false, second_point, second_radius)
} else {
(true, first_point, first_radius)
};
let rad = Circle::Radius(NonNegative(Length::from_px(radius.value)));
let shape = generic::EndingShape::Circle(rad);
let position = Position::new(point.horizontal.into(), point.vertical.into());
let items = Gradient::parse_webkit_gradient_stops(context, input, reverse_stops)?;
generic::Gradient::Radial {
shape,
position,
color_interpolation_method: ColorInterpolationMethod::srgb(),
items,
// Legacy gradients always use srgb as a default.
flags: generic::GradientFlags::HAS_DEFAULT_COLOR_INTERPOLATION_METHOD,
compat_mode: GradientCompatMode::Modern,
}
},
_ => {
let e = SelectorParseErrorKind::UnexpectedIdent(ident.clone());
return Err(input.new_custom_error(e));
},
})
}
fn parse_webkit_gradient_stops<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
reverse_stops: bool,
) -> Result<LengthPercentageItemList, ParseError<'i>> {
let mut items = input
.try_parse(|i| {
i.expect_comma()?;
i.parse_comma_separated(|i| {
let function = i.expect_function()?.clone();
let (color, mut p) = i.parse_nested_block(|i| {
let p = match_ignore_ascii_case! { &function,
"color-stop" => {
let p = NumberOrPercentage::parse(context, i)?.to_percentage();
i.expect_comma()?;
p
},
"from" => Percentage::zero(),
"to" => Percentage::hundred(),
_ => {
return Err(i.new_custom_error(
StyleParseErrorKind::UnexpectedFunction(function.clone())
))
},
};
let color = Color::parse(context, i)?;
if color == Color::CurrentColor {
return Err(i.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok((color.into(), p))
})?;
if reverse_stops {
p.reverse();
}
Ok(generic::GradientItem::ComplexColorStop {
color,
position: p.into(),
})
})
})
.unwrap_or(vec![]);
if items.is_empty() {
items = vec![
generic::GradientItem::ComplexColorStop {
color: Color::transparent(),
position: LengthPercentage::zero_percent(),
},
generic::GradientItem::ComplexColorStop {
color: Color::transparent(),
position: LengthPercentage::hundred_percent(),
},
];
} else if items.len() == 1 {
let first = items[0].clone();
items.push(first);
} else {
items.sort_by(|a, b| {
match (a, b) {
(
&generic::GradientItem::ComplexColorStop {
position: ref a_position,
..
},
&generic::GradientItem::ComplexColorStop {
position: ref b_position,
..
},
) => match (a_position, b_position) {
(&LengthPercentage::Percentage(a), &LengthPercentage::Percentage(b)) => {
return a.0.partial_cmp(&b.0).unwrap_or(Ordering::Equal);
},
_ => {},
},
_ => {},
}
if reverse_stops {
Ordering::Greater
} else {
Ordering::Less
}
})
}
Ok(items.into())
}
/// Not used for -webkit-gradient syntax and conic-gradient
fn parse_stops<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<LengthPercentageItemList, ParseError<'i>> {
let items =
generic::GradientItem::parse_comma_separated(context, input, LengthPercentage::parse)?;
if items.len() < 2 {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok(items)
}
/// Try to parse a color interpolation method.
fn try_parse_color_interpolation_method<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Option<ColorInterpolationMethod> {
if gradient_color_interpolation_method_enabled() {
input
.try_parse(|i| ColorInterpolationMethod::parse(context, i))
.ok()
} else {
None
}
}
/// Parses a linear gradient.
/// GradientCompatMode can change during `-moz-` prefixed gradient parsing if it come across a `to` keyword.
fn parse_linear<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
repeating: bool,
mut compat_mode: GradientCompatMode,
) -> Result<Self, ParseError<'i>> {
let mut flags = GradientFlags::empty();
flags.set(GradientFlags::REPEATING, repeating);
let mut color_interpolation_method =
Self::try_parse_color_interpolation_method(context, input);
let direction = input
.try_parse(|p| LineDirection::parse(context, p, &mut compat_mode))
.ok();
if direction.is_some() && color_interpolation_method.is_none() {
color_interpolation_method = Self::try_parse_color_interpolation_method(context, input);
}
// If either of the 2 options were specified, we require a comma.
if color_interpolation_method.is_some() || direction.is_some() {
input.expect_comma()?;
}
let items = Gradient::parse_stops(context, input)?;
let default = default_color_interpolation_method(&items);
let color_interpolation_method = color_interpolation_method.unwrap_or(default);
flags.set(
GradientFlags::HAS_DEFAULT_COLOR_INTERPOLATION_METHOD,
default == color_interpolation_method,
);
let direction = direction.unwrap_or(match compat_mode {
GradientCompatMode::Modern => LineDirection::Vertical(VerticalPositionKeyword::Bottom),
_ => LineDirection::Vertical(VerticalPositionKeyword::Top),
});
Ok(Gradient::Linear {
direction,
color_interpolation_method,
items,
flags,
compat_mode,
})
}
/// Parses a radial gradient.
fn parse_radial<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
repeating: bool,
compat_mode: GradientCompatMode,
) -> Result<Self, ParseError<'i>> {
let mut flags = GradientFlags::empty();
flags.set(GradientFlags::REPEATING, repeating);
let mut color_interpolation_method =
Self::try_parse_color_interpolation_method(context, input);
let (shape, position) = match compat_mode {
GradientCompatMode::Modern => {
let shape = input.try_parse(|i| EndingShape::parse(context, i, compat_mode));
let position = input.try_parse(|i| {
i.expect_ident_matching("at")?;
Position::parse(context, i)
});
(shape, position.ok())
},
_ => {
let position = input.try_parse(|i| Position::parse(context, i));
let shape = input.try_parse(|i| {
if position.is_ok() {
i.expect_comma()?;
}
EndingShape::parse(context, i, compat_mode)
});
(shape, position.ok())
},
};
let has_shape_or_position = shape.is_ok() || position.is_some();
if has_shape_or_position && color_interpolation_method.is_none() {
color_interpolation_method = Self::try_parse_color_interpolation_method(context, input);
}
if has_shape_or_position || color_interpolation_method.is_some() {
input.expect_comma()?;
}
let shape = shape.unwrap_or({
generic::EndingShape::Ellipse(Ellipse::Extent(ShapeExtent::FarthestCorner))
});
let position = position.unwrap_or(Position::center());
let items = Gradient::parse_stops(context, input)?;
let default = default_color_interpolation_method(&items);
let color_interpolation_method = color_interpolation_method.unwrap_or(default);
flags.set(
GradientFlags::HAS_DEFAULT_COLOR_INTERPOLATION_METHOD,
default == color_interpolation_method,
);
Ok(Gradient::Radial {
shape,
position,
color_interpolation_method,
items,
flags,
compat_mode,
})
}
/// Parse a conic gradient.
fn parse_conic<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
repeating: bool,
) -> Result<Self, ParseError<'i>> {
let mut flags = GradientFlags::empty();
flags.set(GradientFlags::REPEATING, repeating);
let mut color_interpolation_method =
Self::try_parse_color_interpolation_method(context, input);
let angle = input.try_parse(|i| {
i.expect_ident_matching("from")?;
// Spec allows unitless zero start angles
Angle::parse_with_unitless(context, i)
});
let position = input.try_parse(|i| {
i.expect_ident_matching("at")?;
Position::parse(context, i)
});
let has_angle_or_position = angle.is_ok() || position.is_ok();
if has_angle_or_position && color_interpolation_method.is_none() {
color_interpolation_method = Self::try_parse_color_interpolation_method(context, input);
}
if has_angle_or_position || color_interpolation_method.is_some() {
input.expect_comma()?;
}
let angle = angle.unwrap_or(Angle::zero());
let position = position.unwrap_or(Position::center());
let items = generic::GradientItem::parse_comma_separated(
context,
input,
AngleOrPercentage::parse_with_unitless,
)?;
if items.len() < 2 {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
let default = default_color_interpolation_method(&items);
let color_interpolation_method = color_interpolation_method.unwrap_or(default);
flags.set(
GradientFlags::HAS_DEFAULT_COLOR_INTERPOLATION_METHOD,
default == color_interpolation_method,
);
Ok(Gradient::Conic {
angle,
position,
color_interpolation_method,
items,
flags,
})
}
}
impl generic::LineDirection for LineDirection {
fn points_downwards(&self, compat_mode: GradientCompatMode) -> bool {
match *self {
LineDirection::Angle(ref angle) => angle.degrees() == 180.0,
LineDirection::Vertical(VerticalPositionKeyword::Bottom) => {
compat_mode == GradientCompatMode::Modern
},
LineDirection::Vertical(VerticalPositionKeyword::Top) => {
compat_mode != GradientCompatMode::Modern
},
_ => false,
}
}
fn to_css<W>(&self, dest: &mut CssWriter<W>, compat_mode: GradientCompatMode) -> fmt::Result
where
W: Write,
{
match *self {
LineDirection::Angle(angle) => angle.to_css(dest),
LineDirection::Horizontal(x) => {
if compat_mode == GradientCompatMode::Modern {
dest.write_str("to ")?;
}
x.to_css(dest)
},
LineDirection::Vertical(y) => {
if compat_mode == GradientCompatMode::Modern {
dest.write_str("to ")?;
}
y.to_css(dest)
},
LineDirection::Corner(x, y) => {
if compat_mode == GradientCompatMode::Modern {
dest.write_str("to ")?;
}
x.to_css(dest)?;
dest.write_char(' ')?;
y.to_css(dest)
},
}
}
}
impl LineDirection {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
compat_mode: &mut GradientCompatMode,
) -> Result<Self, ParseError<'i>> {
// Gradients allow unitless zero angles as an exception, see:
if let Ok(angle) = input.try_parse(|i| Angle::parse_with_unitless(context, i)) {
return Ok(LineDirection::Angle(angle));
}
input.try_parse(|i| {
let to_ident = i.try_parse(|i| i.expect_ident_matching("to"));
match *compat_mode {
// `to` keyword is mandatory in modern syntax.
GradientCompatMode::Modern => to_ident?,
// Fall back to Modern compatibility mode in case there is a `to` keyword.
// According to Gecko, `-moz-linear-gradient(to ...)` should serialize like
// `linear-gradient(to ...)`.
GradientCompatMode::Moz if to_ident.is_ok() => {
*compat_mode = GradientCompatMode::Modern
},
// There is no `to` keyword in webkit prefixed syntax. If it's consumed,
// parsing should throw an error.
GradientCompatMode::WebKit if to_ident.is_ok() => {
return Err(
i.new_custom_error(SelectorParseErrorKind::UnexpectedIdent("to".into()))
);
},
_ => {},
}
if let Ok(x) = i.try_parse(HorizontalPositionKeyword::parse) {
if let Ok(y) = i.try_parse(VerticalPositionKeyword::parse) {
return Ok(LineDirection::Corner(x, y));
}
return Ok(LineDirection::Horizontal(x));
}
let y = VerticalPositionKeyword::parse(i)?;
if let Ok(x) = i.try_parse(HorizontalPositionKeyword::parse) {
return Ok(LineDirection::Corner(x, y));
}
Ok(LineDirection::Vertical(y))
})
}
}
impl EndingShape {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
compat_mode: GradientCompatMode,
) -> Result<Self, ParseError<'i>> {
if let Ok(extent) = input.try_parse(|i| ShapeExtent::parse_with_compat_mode(i, compat_mode))
{
if input
.try_parse(|i| i.expect_ident_matching("circle"))
.is_ok()
{
return Ok(generic::EndingShape::Circle(Circle::Extent(extent)));
}
let _ = input.try_parse(|i| i.expect_ident_matching("ellipse"));
return Ok(generic::EndingShape::Ellipse(Ellipse::Extent(extent)));
}
if input
.try_parse(|i| i.expect_ident_matching("circle"))
.is_ok()
{
if let Ok(extent) =
input.try_parse(|i| ShapeExtent::parse_with_compat_mode(i, compat_mode))
{
return Ok(generic::EndingShape::Circle(Circle::Extent(extent)));
}
if compat_mode == GradientCompatMode::Modern {
if let Ok(length) = input.try_parse(|i| NonNegativeLength::parse(context, i)) {
return Ok(generic::EndingShape::Circle(Circle::Radius(length)));
}
}
return Ok(generic::EndingShape::Circle(Circle::Extent(
ShapeExtent::FarthestCorner,
)));
}
if input
.try_parse(|i| i.expect_ident_matching("ellipse"))
.is_ok()
{
if let Ok(extent) =
input.try_parse(|i| ShapeExtent::parse_with_compat_mode(i, compat_mode))
{
return Ok(generic::EndingShape::Ellipse(Ellipse::Extent(extent)));
}
if compat_mode == GradientCompatMode::Modern {
let pair: Result<_, ParseError> = input.try_parse(|i| {
let x = NonNegativeLengthPercentage::parse(context, i)?;
let y = NonNegativeLengthPercentage::parse(context, i)?;
Ok((x, y))
});
if let Ok((x, y)) = pair {
return Ok(generic::EndingShape::Ellipse(Ellipse::Radii(x, y)));
}
}
return Ok(generic::EndingShape::Ellipse(Ellipse::Extent(
ShapeExtent::FarthestCorner,
)));
}
if let Ok(length) = input.try_parse(|i| NonNegativeLength::parse(context, i)) {
if let Ok(y) = input.try_parse(|i| NonNegativeLengthPercentage::parse(context, i)) {
if compat_mode == GradientCompatMode::Modern {
let _ = input.try_parse(|i| i.expect_ident_matching("ellipse"));
}
return Ok(generic::EndingShape::Ellipse(Ellipse::Radii(
NonNegative(LengthPercentage::from(length.0)),
y,
)));
}
if compat_mode == GradientCompatMode::Modern {
let y = input.try_parse(|i| {
i.expect_ident_matching("ellipse")?;
NonNegativeLengthPercentage::parse(context, i)
});
if let Ok(y) = y {
return Ok(generic::EndingShape::Ellipse(Ellipse::Radii(
NonNegative(LengthPercentage::from(length.0)),
y,
)));
}
let _ = input.try_parse(|i| i.expect_ident_matching("circle"));
}
return Ok(generic::EndingShape::Circle(Circle::Radius(length)));
}
input.try_parse(|i| {
let x = Percentage::parse_non_negative(context, i)?;
let y = if let Ok(y) = i.try_parse(|i| NonNegativeLengthPercentage::parse(context, i)) {
if compat_mode == GradientCompatMode::Modern {
let _ = i.try_parse(|i| i.expect_ident_matching("ellipse"));
}
y
} else {
if compat_mode == GradientCompatMode::Modern {
i.expect_ident_matching("ellipse")?;
}
NonNegativeLengthPercentage::parse(context, i)?
};
Ok(generic::EndingShape::Ellipse(Ellipse::Radii(
NonNegative(LengthPercentage::from(x)),
y,
)))
})
}
}
impl ShapeExtent {
fn parse_with_compat_mode<'i, 't>(
input: &mut Parser<'i, 't>,
compat_mode: GradientCompatMode,
) -> Result<Self, ParseError<'i>> {
match Self::parse(input)? {
ShapeExtent::Contain | ShapeExtent::Cover
if compat_mode == GradientCompatMode::Modern =>
{
Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
},
ShapeExtent::Contain => Ok(ShapeExtent::ClosestSide),
ShapeExtent::Cover => Ok(ShapeExtent::FarthestCorner),
keyword => Ok(keyword),
}
}
}
impl<T> generic::GradientItem<Color, T> {
fn parse_comma_separated<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
parse_position: impl for<'i1, 't1> Fn(&ParserContext, &mut Parser<'i1, 't1>) -> Result<T, ParseError<'i1>>
+ Copy,
) -> Result<crate::OwnedSlice<Self>, ParseError<'i>> {
let mut items = Vec::new();
let mut seen_stop = false;
loop {
input.parse_until_before(Delimiter::Comma, |input| {
if seen_stop {
if let Ok(hint) = input.try_parse(|i| parse_position(context, i)) {
seen_stop = false;
items.push(generic::GradientItem::InterpolationHint(hint));
return Ok(());
}
}
let stop = generic::ColorStop::parse(context, input, parse_position)?;
if let Ok(multi_position) = input.try_parse(|i| parse_position(context, i)) {
let stop_color = stop.color.clone();
items.push(stop.into_item());
items.push(
generic::ColorStop {
color: stop_color,
position: Some(multi_position),
}
.into_item(),
);
} else {
items.push(stop.into_item());
}
seen_stop = true;
Ok(())
})?;
match input.next() {
Err(_) => break,
Ok(&Token::Comma) => continue,
Ok(_) => unreachable!(),
}
}
if !seen_stop || items.len() < 2 {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok(items.into())
}
}
impl<T> generic::ColorStop<Color, T> {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
parse_position: impl for<'i1, 't1> Fn(
&ParserContext,
&mut Parser<'i1, 't1>,
) -> Result<T, ParseError<'i1>>,
) -> Result<Self, ParseError<'i>> {
Ok(generic::ColorStop {
color: Color::parse(context, input)?,
position: input.try_parse(|i| parse_position(context, i)).ok(),
})
}
}
impl PaintWorklet {
#[cfg(feature = "servo")]
fn parse_args<'i>(input: &mut Parser<'i, '_>) -> Result<Self, ParseError<'i>> {
use crate::custom_properties::SpecifiedValue;
let name = Atom::from(&**input.expect_ident()?);
let arguments = input
.try_parse(|input| {
input.expect_comma()?;
input.parse_comma_separated(SpecifiedValue::parse)
})
.unwrap_or_default();
Ok(Self { name, arguments })
}
}
#[allow(missing_docs)]
#[derive(
Clone,
Copy,
Debug,
Eq,
Hash,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToCss,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
#[repr(u8)]
pub enum ImageRendering {
Auto,
#[cfg(feature = "gecko")]
Smooth,
#[parse(aliases = "-moz-crisp-edges")]
CrispEdges,
Pixelated,
// From the spec:
//
// This property previously accepted the values optimizeSpeed and
// optimizeQuality. These are now deprecated; a user agent must accept
// them as valid values but must treat them as having the same behavior
// as crisp-edges and smooth respectively, and authors must not use
// them.
//
#[cfg(feature = "gecko")]
Optimizespeed,
#[cfg(feature = "gecko")]
Optimizequality,
}