css_parse/syntax/
declaration_list.rs

1use crate::{
2	CursorSink, Declaration, DeclarationValue, Kind, KindSet, NodeMetadata, NodeWithMetadata, Parse, Parser, Peek,
3	Result, SemanticEq, Span, T, ToCursors, ToSpan, Vec, token_macros,
4};
5use csskit_proc_macro::node;
6
7/// A generic struct that can be used for AST nodes representing a rule's block, that is only capable of having child
8/// declarations.
9///
10/// It is an [implementation of "declaration-list"][1]. It includes an error tolerance in that the ending `}` token can
11/// be omitted, if at the end of the file.
12///
13/// The `<V>` must implement the [DeclarationValue] trait, as it is passed to [Declaration].
14///
15/// ```md
16/// <declaration-list>
17///  │├─ "{" ─╮─╭─ <declaration> ──╮─╭─╮─ "}" ─╭─┤│
18///           │ │                  │ │ ╰───────╯
19///           │ ╰──────────────────╯ │
20///           ╰──────────────────────╯
21/// ```
22///
23/// [1]: https://drafts.csswg.org/css-syntax-3/#typedef-declaration-list
24#[node]
25#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
26#[cfg_attr(feature = "serde", derive(serde::Serialize))]
27#[cfg_attr(feature = "serde", serde(bound(serialize = "V: serde::Serialize")))]
28pub struct DeclarationList<'a, V, M>
29where
30	V: DeclarationValue<'a, M>,
31	M: NodeMetadata,
32{
33	pub open_curly: token_macros::LeftCurly,
34	pub declarations: Vec<'a, Declaration<'a, V, M>>,
35	pub close_curly: Option<token_macros::RightCurly>,
36	#[cfg_attr(feature = "serde", serde(skip))]
37	meta: M,
38}
39
40impl<'a, V, M> NodeWithMetadata<M> for DeclarationList<'a, V, M>
41where
42	V: DeclarationValue<'a, M>,
43	M: NodeMetadata,
44{
45	fn metadata(&self) -> M {
46		self.meta
47	}
48}
49
50impl<'a, V, M> Peek<'a> for DeclarationList<'a, V, M>
51where
52	V: DeclarationValue<'a, M>,
53	M: NodeMetadata,
54{
55	const PEEK_KINDSET: KindSet = KindSet::new(&[Kind::LeftCurly]);
56}
57
58impl<'a, V, M> Parse<'a> for DeclarationList<'a, V, M>
59where
60	V: DeclarationValue<'a, M>,
61	M: NodeMetadata,
62{
63	fn parse<Iter>(p: &mut Parser<'a, Iter>) -> Result<Self>
64	where
65		Iter: Iterator<Item = crate::Cursor> + Clone,
66	{
67		let open_curly = p.parse::<T!['{']>()?;
68		let mut declarations = Vec::new_in(p.alloc());
69		let mut meta: M = Default::default();
70		loop {
71			if p.at_end() {
72				meta = meta.with_size(declarations.len().min(u16::MAX as usize) as u16);
73				return Ok(Self { open_curly, declarations, close_curly: None, meta });
74			}
75			let close_curly = p.parse_if_peek::<T!['}']>()?;
76			if close_curly.is_some() {
77				meta = meta.with_size(declarations.len().min(u16::MAX as usize) as u16);
78				return Ok(Self { open_curly, declarations, close_curly, meta });
79			}
80			let declaration = p.parse::<Declaration<'a, V, M>>()?;
81			meta = meta.merge(declaration.metadata());
82			declarations.push(declaration);
83		}
84	}
85}
86
87impl<'a, V, M> ToCursors for DeclarationList<'a, V, M>
88where
89	V: DeclarationValue<'a, M> + ToCursors,
90	M: NodeMetadata,
91{
92	fn to_cursors(&self, s: &mut impl CursorSink) {
93		ToCursors::to_cursors(&self.open_curly, s);
94		ToCursors::to_cursors(&self.declarations, s);
95		ToCursors::to_cursors(&self.close_curly, s);
96	}
97}
98
99impl<'a, V, M> ToSpan for DeclarationList<'a, V, M>
100where
101	V: DeclarationValue<'a, M> + ToSpan,
102	M: NodeMetadata,
103{
104	fn to_span(&self) -> Span {
105		self.open_curly.to_span()
106			+ if let Some(close) = self.close_curly { close.to_span() } else { self.declarations.to_span() }
107	}
108}
109
110impl<'a, V, M> SemanticEq for DeclarationList<'a, V, M>
111where
112	V: DeclarationValue<'a, M>,
113	M: NodeMetadata,
114{
115	fn semantic_eq(&self, other: &Self) -> bool {
116		self.open_curly.semantic_eq(&other.open_curly)
117			&& self.declarations.semantic_eq(&other.declarations)
118			&& self.close_curly.semantic_eq(&other.close_curly)
119	}
120}
css_parse/syntax/declaration_list.rs

css_parse/syntax/
declaration_list.rs
