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Diffstat (limited to 'servo/components/style/values/specified/image.rs')
-rw-r--r-- | servo/components/style/values/specified/image.rs | 1296 |
1 files changed, 1296 insertions, 0 deletions
diff --git a/servo/components/style/values/specified/image.rs b/servo/components/style/values/specified/image.rs new file mode 100644 index 0000000000..0f38400768 --- /dev/null +++ b/servo/components/style/values/specified/image.rs @@ -0,0 +1,1296 @@ +/* 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/. */ + +//! CSS handling for the specified value of +//! [`image`][image]s +//! +//! [image]: https://drafts.csswg.org/css-images/#image-values + +use crate::custom_properties::SpecifiedValue; +use crate::parser::{Parse, ParserContext}; +use crate::stylesheets::CorsMode; +use crate::values::generics::image::PaintWorklet; +use crate::values::generics::image::{ + self as generic, Circle, Ellipse, GradientCompatMode, ShapeExtent, +}; +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; +#[cfg(feature = "servo")] +use servo_url::ServoUrl; +use std::cmp::Ordering; +use std::fmt::{self, Write}; +use style_traits::{CssType, CssWriter, KeywordsCollectFn, ParseError}; +use style_traits::{SpecifiedValueInfo, StyleParseErrorKind, ToCss}; + +/// Specified values for an image according to CSS-IMAGES. +/// <https://drafts.csswg.org/css-images/#image-values> +pub type Image = + generic::Image<Gradient, MozImageRect, SpecifiedImageUrl, Color, Percentage, Resolution>; + +// Images should remain small, see https://github.com/servo/servo/pull/18430 +size_of_test!(Image, 16); + +/// Specified values for a CSS gradient. +/// <https://drafts.csswg.org/css-images/#gradients> +pub type Gradient = generic::Gradient< + LineDirection, + LengthPercentage, + NonNegativeLength, + NonNegativeLengthPercentage, + Position, + Angle, + AngleOrPercentage, + Color, +>; + +/// Specified values for CSS cross-fade +/// cross-fade( CrossFadeElement, ...) +/// <https://drafts.csswg.org/css-images-4/#cross-fade-function> +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>>; + +#[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>; + +/// Specified values for `moz-image-rect` +/// -moz-image-rect(<uri>, top, right, bottom, left); +#[cfg(all(feature = "gecko", not(feature = "cbindgen")))] +pub type MozImageRect = generic::GenericMozImageRect<NumberOrPercentage, SpecifiedImageUrl>; + +#[cfg(not(feature = "gecko"))] +#[derive( + Clone, + Debug, + MallocSizeOf, + PartialEq, + SpecifiedValueInfo, + ToComputedValue, + ToCss, + ToResolvedValue, + ToShmem, +)] +/// Empty enum on non-Gecko +pub enum MozImageRect {} + +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))); + } + + if cross_fade_enabled() { + if let Ok(cf) = + input.try_parse(|input| CrossFade::parse(context, input, cors_mode, flags)) + { + return Ok(generic::Image::CrossFade(Box::new(cf))); + } + } + #[cfg(feature = "servo-layout-2013")] + { + if let Ok(paint_worklet) = input.try_parse(|i| PaintWorklet::parse(context, i)) { + return Ok(generic::Image::PaintWorklet(paint_worklet)); + } + } + #[cfg(feature = "gecko")] + { + if let Ok(image_rect) = + input.try_parse(|input| MozImageRect::parse(context, input, cors_mode)) + { + return Ok(generic::Image::Rect(Box::new(image_rect))); + } + Ok(generic::Image::Element(Image::parse_element(input)?)) + } + #[cfg(not(feature = "gecko"))] + Err(input.new_error_for_next_token()) + } +} + +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: ServoUrl) -> 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, 't>(input: &mut Parser<'i, 't>) -> Result<Atom, ParseError<'i>> { + input.try_parse(|i| i.expect_function_matching("-moz-element"))?; + let location = input.current_source_location(); + input.parse_nested_block(|i| match *i.next()? { + Token::IDHash(ref id) => Ok(Atom::from(id.as_ref())), + ref t => 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<'i, 't>( + context: &ParserContext, + input: &mut Parser<'i, 't>, + cors_mode: CorsMode, + flags: ParseImageFlags, + ) -> Result<Self, ParseError<'i>> { + input.expect_function_matching("cross-fade")?; + let elements = input.parse_nested_block(|input| { + input.parse_comma_separated(|input| { + CrossFadeElement::parse(context, input, cors_mode, flags) + }) + })?; + let elements = crate::OwnedSlice::from(elements); + 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. + // See: <https://github.com/w3c/csswg-drafts/issues/5333> + 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), + } + + impl LineDirection { + fn from_points(first: Point, second: Point) -> Self { + 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 From<Point> for Position { + fn from(point: Point) -> Self { + Self::new(point.horizontal.into(), point.vertical.into()) + } + } + + 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> From<Component<S>> for NumberOrPercentage { + fn from(component: Component<S>) -> Self { + match component { + 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> From<Component<S>> for PositionComponent<S> { + fn from(component: Component<S>) -> Self { + match component { + 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 ( + NumberOrPercentage::from(*self), + NumberOrPercentage::from(*other), + ) { + (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 = LineDirection::from_points(first, second); + let items = Gradient::parse_webkit_gradient_stops(context, input, false)?; + + generic::Gradient::Linear { + direction, + items, + repeating: false, + 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 = point.into(); + let items = Gradient::parse_webkit_gradient_stops(context, input, reverse_stops)?; + + generic::Gradient::Radial { + shape, + position, + items, + repeating: false, + 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) + } + + /// 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 direction = if let Ok(d) = + input.try_parse(|i| LineDirection::parse(context, i, &mut compat_mode)) + { + input.expect_comma()?; + d + } else { + match compat_mode { + GradientCompatMode::Modern => { + LineDirection::Vertical(VerticalPositionKeyword::Bottom) + }, + _ => LineDirection::Vertical(VerticalPositionKeyword::Top), + } + }; + let items = Gradient::parse_stops(context, input)?; + + Ok(Gradient::Linear { + direction, + items, + repeating, + 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 (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()) + }, + }; + + if shape.is_ok() || position.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)?; + + Ok(Gradient::Radial { + shape, + position, + items, + repeating, + compat_mode, + }) + } + fn parse_conic<'i, 't>( + context: &ParserContext, + input: &mut Parser<'i, 't>, + repeating: bool, + ) -> Result<Self, ParseError<'i>> { + let angle = input.try_parse(|i| { + i.expect_ident_matching("from")?; + // Spec allows unitless zero start angles + // https://drafts.csswg.org/css-images-4/#valdef-conic-gradient-angle + Angle::parse_with_unitless(context, i) + }); + let position = input.try_parse(|i| { + i.expect_ident_matching("at")?; + Position::parse(context, i) + }); + if angle.is_ok() || position.is_ok() { + 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)); + } + + Ok(Gradient::Conic { + angle, + position, + items, + repeating, + }) + } +} + +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: + // https://github.com/w3c/csswg-drafts/issues/1162 + 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 Parse for PaintWorklet { + fn parse<'i, 't>( + _context: &ParserContext, + input: &mut Parser<'i, 't>, + ) -> Result<Self, ParseError<'i>> { + input.expect_function_matching("paint")?; + input.parse_nested_block(|input| { + let name = Atom::from(&**input.expect_ident()?); + let arguments = input + .try_parse(|input| { + input.expect_comma()?; + input.parse_comma_separated(|input| SpecifiedValue::parse(input)) + }) + .unwrap_or(vec![]); + Ok(PaintWorklet { name, arguments }) + }) + } +} + +impl MozImageRect { + #[cfg(feature = "gecko")] + fn parse<'i, 't>( + context: &ParserContext, + input: &mut Parser<'i, 't>, + cors_mode: CorsMode, + ) -> Result<Self, ParseError<'i>> { + input.try_parse(|i| i.expect_function_matching("-moz-image-rect"))?; + input.parse_nested_block(|i| { + let string = i.expect_url_or_string()?; + let url = SpecifiedImageUrl::parse_from_string( + string.as_ref().to_owned(), + context, + cors_mode, + ); + i.expect_comma()?; + let top = NumberOrPercentage::parse_non_negative(context, i)?; + i.expect_comma()?; + let right = NumberOrPercentage::parse_non_negative(context, i)?; + i.expect_comma()?; + let bottom = NumberOrPercentage::parse_non_negative(context, i)?; + i.expect_comma()?; + let left = NumberOrPercentage::parse_non_negative(context, i)?; + Ok(MozImageRect { + url, + top, + right, + bottom, + left, + }) + }) + } +} + +/// https://drafts.csswg.org/css-images/#propdef-image-rendering +#[allow(missing_docs)] +#[derive( + Clone, + Copy, + Debug, + Eq, + Hash, + MallocSizeOf, + Parse, + PartialEq, + SpecifiedValueInfo, + ToCss, + ToComputedValue, + ToResolvedValue, + ToShmem, +)] +#[repr(u8)] +pub enum ImageRendering { + Auto, + 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. + // + Optimizespeed, + Optimizequality, +} |