css_ast/selector/
namespace.rs

1use css_parse::{Cursor, Diagnostic, KindSet, Parse, Parser, Result as ParserResult, T};
2use csskit_derives::{IntoCursor, Peek, SemanticEq, ToCursors, ToSpan};
3
4use super::Tag;
5
6// https://drafts.csswg.org/selectors/#combinators
7#[derive(Peek, ToSpan, ToCursors, SemanticEq, Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
8#[cfg_attr(feature = "serde", derive(serde::Serialize), serde())]
9#[cfg_attr(feature = "visitable", derive(csskit_derives::Visitable), visit(self))]
10pub struct Namespace {
11	pub prefix: Option<NamespacePrefix>,
12	pub tag: NamespaceTag,
13}
14
15impl<'a> Parse<'a> for Namespace {
16	fn parse<I>(p: &mut Parser<'a, I>) -> ParserResult<Self>
17	where
18		I: Iterator<Item = Cursor> + Clone,
19	{
20		if p.peek::<T![*|]>() {
21			let prefix = p.parse::<NamespacePrefix>()?;
22			let tag = p.parse::<NamespaceTag>()?;
23			return Ok(Self { prefix: Some(prefix), tag });
24		}
25		if p.peek::<T![|]>() {
26			let prefix = p.parse::<NamespacePrefix>()?;
27			let tag = p.parse::<NamespaceTag>()?;
28			return Ok(Self { prefix: Some(prefix), tag });
29		}
30
31		let ident = p.parse::<T![Ident]>()?;
32		let skip = p.set_skip(KindSet::NONE);
33		if p.peek::<T![|]>() && !p.peek::<T![|=]>() {
34			let pipe = p.parse::<T![|]>();
35			let tag = p.parse::<NamespaceTag>();
36			p.set_skip(skip);
37			let prefix = NamespacePrefix::Name(ident, pipe?);
38			return Ok(Self { prefix: Some(prefix), tag: tag? });
39		}
40		let tag = p.parse::<NamespaceTag>()?;
41		Ok(Self { prefix: None, tag })
42	}
43}
44
45#[derive(Peek, ToSpan, ToCursors, SemanticEq, Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
46#[cfg_attr(feature = "serde", derive(serde::Serialize), serde())]
47pub enum NamespacePrefix {
48	None(T![|]),
49	Name(T![Ident], T![|]),
50	Wildcard(T![*], T![|]),
51}
52
53impl<'a> Parse<'a> for NamespacePrefix {
54	fn parse<I>(p: &mut Parser<'a, I>) -> ParserResult<Self>
55	where
56		I: Iterator<Item = Cursor> + Clone,
57	{
58		if p.peek::<T![|]>() {
59			let pipe = p.parse::<T![|]>()?;
60			Ok(Self::None(pipe))
61		} else if p.peek::<T![*]>() {
62			let star = p.parse::<T![*]>()?;
63			let skip = p.set_skip(KindSet::NONE);
64			let pipe = p.parse::<T![|]>();
65			p.set_skip(skip);
66			let pipe = pipe?;
67			Ok(Self::Wildcard(star, pipe))
68		} else {
69			let star = p.parse::<T![Ident]>()?;
70			let skip = p.set_skip(KindSet::NONE);
71			let pipe = p.parse::<T![|]>();
72			p.set_skip(skip);
73			let pipe = pipe?;
74			Ok(Self::Name(star, pipe))
75		}
76	}
77}
78
79#[derive(Peek, ToCursors, IntoCursor, Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
80#[cfg_attr(feature = "serde", derive(serde::Serialize), serde())]
81pub enum NamespaceTag {
82	Wildcard(T![*]),
83	Tag(Tag),
84}
85
86impl<'a> Parse<'a> for NamespaceTag {
87	fn parse<I>(p: &mut Parser<'a, I>) -> ParserResult<Self>
88	where
89		I: Iterator<Item = Cursor> + Clone,
90	{
91		if p.peek::<Self>() {
92			if p.peek::<T![*]>() { Ok(Self::Wildcard(p.parse::<T![*]>()?)) } else { Ok(Self::Tag(p.parse::<Tag>()?)) }
93		} else {
94			Err(Diagnostic::new(p.next(), Diagnostic::unexpected))?
95		}
96	}
97}
98
99#[cfg(test)]
100mod tests {
101	use super::*;
102	use crate::CssAtomSet;
103	use css_parse::{assert_parse, assert_parse_error};
104
105	#[test]
106	fn size_test() {
107		assert_eq!(std::mem::size_of::<Namespace>(), 48);
108	}
109
110	#[test]
111	fn test_writes() {
112		assert_parse!(CssAtomSet::ATOMS, Namespace, "*|a");
113		assert_parse!(CssAtomSet::ATOMS, Namespace, "html|div");
114		assert_parse!(CssAtomSet::ATOMS, Namespace, "|span");
115	}
116
117	#[test]
118	fn test_errors() {
119		assert_parse_error!(CssAtomSet::ATOMS, Namespace, "* | a");
120	}
121}
css_ast/selector/namespace.rs

css_ast/selector/
namespace.rs
