lewp_css/domain/at_rules/document/document_condition.rs
1// This file is part of css. It is subject to the license terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/css/master/COPYRIGHT. No part of predicator, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
2// Copyright © 2017 The developers of css. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/css/master/COPYRIGHT.
3
4use {
5 super::{Document, UrlMatchingFunction},
6 crate::{parsers::ParserContext, CustomParseError},
7 cssparser::{ParseError, Parser, ToCss},
8 std::fmt,
9};
10
11/// A `@document` rule's condition.
12///
13/// <https://www.w3.org/TR/2012/WD-css3-conditional-20120911/#at-document>
14///
15/// The `@document` rule's condition is written as a comma-separated list of URL matching functions, and the condition evaluates to true whenever any one of those functions evaluates to true.
16#[derive(Clone, Debug)]
17pub struct DocumentCondition(pub Vec<UrlMatchingFunction>);
18
19impl ToCss for DocumentCondition {
20 fn to_css<W: fmt::Write>(&self, dest: &mut W) -> fmt::Result {
21 let mut iter = self.0.iter();
22 let first = iter.next().expect("Empty DocumentCondition, should contain at least one URL matching function");
23 first.to_css(dest)?;
24 for url_matching_function in iter {
25 dest.write_str(", ")?;
26 url_matching_function.to_css(dest)?;
27 }
28 Ok(())
29 }
30}
31
32impl DocumentCondition {
33 /// Parse a document condition.
34 pub(crate) fn parse<'i, 't>(
35 context: &ParserContext,
36 input: &mut Parser<'i, 't>,
37 ) -> Result<Self, ParseError<'i, CustomParseError<'i>>> {
38 input
39 .parse_comma_separated(|input| {
40 UrlMatchingFunction::parse(context, input)
41 })
42 .map(DocumentCondition)
43 }
44
45 /// Evaluate a document condition.
46 pub fn evaluate<D: Document>(&self, document: &D) -> bool {
47 self.0.iter().any(|url_matching_function| {
48 url_matching_function.evaluate(document)
49 })
50 }
51}