css_ast/functions/
cross_fade_function.rs

1use super::prelude::*;
2use crate::{CalcableValue, Color, Image, Percentage, Ranged};
3
4/// <https://drafts.csswg.org/css-images-4/#funcdef-cross-fade>
5///
6/// ```text,ignore
7/// <cross-fade()> = cross-fade( <cf-image># )
8/// <cf-image> = [ <image> | <color> ] && <percentage [0,100]>?
9/// ```
10#[node]
11#[derive(Parse, Peek, ToSpan, ToCursors, SemanticEq, Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
12#[cfg_attr(feature = "serde", derive(serde::Serialize), serde())]
13#[cfg_attr(feature = "visitable", derive(csskit_derives::Visitable), visit(all))]
14#[derive(csskit_derives::NodeWithMetadata)]
15pub struct CrossFadeFunction<'a> {
16	#[atom(CssAtomSet::CrossFade)]
17	#[cfg_attr(feature = "visitable", visit(skip))]
18	pub name: T![Function],
19	pub params: CommaSeparated<'a, CfImage<'a>>,
20	#[cfg_attr(feature = "visitable", visit(skip))]
21	#[semantic_eq(skip)]
22	pub close: T![')'],
23}
24
25/// An image or color with an optional percentage in a `cross-fade()` function.
26///
27/// ```text,ignore
28/// <cf-image> = [ <image> | <color> ] && <percentage [0,100]>?
29/// ```
30///
31/// The image and percentage can appear in either order.
32#[node]
33#[derive(ToSpan, ToCursors, SemanticEq, Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
34#[cfg_attr(feature = "serde", derive(serde::Serialize), serde())]
35#[cfg_attr(feature = "visitable", derive(csskit_derives::Visitable), visit(children))]
36#[derive(csskit_derives::NodeWithMetadata)]
37pub struct CfImage<'a> {
38	pub image: CfImageValue<'a>,
39	pub percentage: Option<CalcableValue<'a, Ranged<Percentage, 0, 100>>>,
40}
41
42impl<'a> Peek<'a> for CfImage<'a> {
43	const PEEK_KINDSET: KindSet =
44		CfImageValue::PEEK_KINDSET.combine(CalcableValue::<Ranged<Percentage, 0, 100>>::PEEK_KINDSET);
45
46	#[inline(always)]
47	fn peek<I>(p: &Parser<'a, I>, c: Cursor) -> bool
48	where
49		I: Iterator<Item = Cursor> + Clone,
50	{
51		CfImageValue::peek(p, c) || CalcableValue::<Ranged<Percentage, 0, 100>>::peek(p, c)
52	}
53}
54
55impl<'a> Parse<'a> for CfImage<'a> {
56	fn parse<I>(p: &mut Parser<'a, I>) -> ParserResult<Self>
57	where
58		I: Iterator<Item = Cursor> + Clone,
59	{
60		// Either order: <cf-image-value> <percentage>? or <percentage> <cf-image-value>
61		let mut image = p.parse_if_peek::<CfImageValue>()?;
62		let percentage = p.parse_if_peek::<CalcableValue<Ranged<Percentage, 0, 100>>>()?;
63		if image.is_none() {
64			image = Some(p.parse::<CfImageValue>()?);
65		}
66		Ok(Self { image: image.unwrap(), percentage })
67	}
68}
69
70/// The image or color being mixed by one argument of a `cross-fade()` function.
71///
72/// ```text,ignore
73/// [ <image> | <color> ]
74/// ```
75#[node]
76#[derive(Parse, Peek, ToSpan, ToCursors, SemanticEq, Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
77#[cfg_attr(feature = "serde", derive(serde::Serialize), serde())]
78#[cfg_attr(feature = "visitable", derive(csskit_derives::Visitable), visit(children))]
79#[derive(csskit_derives::NodeWithMetadata)]
80pub enum CfImageValue<'a> {
81	Image(Image<'a>),
82	Color(Color<'a>),
83}
84
85#[cfg(test)]
86mod tests {
87	use super::*;
88	use crate::CssAtomSet;
89	use css_parse::{assert_parse, assert_parse_error};
90
91	#[test]
92	fn test_writes() {
93		assert_parse!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(url(a))");
94		assert_parse!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(url(a)20%,url(b)80%)");
95		assert_parse!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(red 20%,blue)");
96		assert_parse!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(20% red,80% blue)");
97		assert_parse!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(linear-gradient(red,blue)50%,url(a))");
98		assert_parse!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(url(a)var(--pct))");
99	}
100
101	#[test]
102	fn test_errors() {
103		assert_parse_error!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade()");
104		assert_parse_error!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(20%)");
105		assert_parse_error!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(red 120%)");
106		assert_parse_error!(CssAtomSet::ATOMS, CrossFadeFunction, "cross-fade(url(a),)");
107	}
108
109	#[test]
110	#[cfg(feature = "visitable")]
111	fn test_visits() {
112		use crate::assert_visits;
113		assert_visits!("cross-fade(red 20%,url(a))", CrossFadeFunction, Color, Percentage, Image, Url);
114	}
115}
css_ast/functions/cross_fade_function.rs

css_ast/functions/
cross_fade_function.rs
