asm_tl 0.2.0

2x-3x faster than rustedbytes-tl, thanks to Assembly
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152

use crate::{asm_core, stream::Stream};

use super::Selector;

/// A query selector parser
pub struct Parser<'a> {
    stream: Stream<'a, u8>,
}

impl<'a> Parser<'a> {
    /// Creates a new query selector parser
    pub fn new(input: &'a [u8]) -> Self {
        Self {
            stream: Stream::new(input),
        }
    }

    fn skip_whitespaces(&mut self) -> bool {
        let skipped = asm_core::count_spaces(&self.stream.data()[self.stream.idx..]);
        self.stream.idx += skipped;
        skipped != 0
    }

    fn read_identifier(&mut self) -> &'a [u8] {
        let start = self.stream.idx;
        let len = asm_core::count_ident(&self.stream.data()[start..]);
        self.stream.advance_by(len);

        self.stream.slice(start, self.stream.idx)
    }

    fn parse_combinator(&mut self, left: Selector<'a>) -> Option<Selector<'a>> {
        let has_whitespaces = self.skip_whitespaces();

        let tok = if let Some(tok) = self.stream.current_cpy() {
            tok
        } else {
            return Some(left);
        };

        let combinator = match asm_core::selector_combinator_kind(tok, has_whitespaces) {
            1 => {
                self.stream.advance();
                let right = self.selector()?;
                Selector::Or(Box::new(left), Box::new(right))
            }
            2 => {
                self.stream.advance();
                let right = self.selector()?;
                Selector::Parent(Box::new(left), Box::new(right))
            }
            3 => {
                let right = self.selector()?;
                Selector::Descendant(Box::new(left), Box::new(right))
            }
            4 => {
                let right = self.selector()?;
                Selector::And(Box::new(left), Box::new(right))
            }
            _ => unreachable!(),
        };

        Some(combinator)
    }

    fn parse_attribute<const MAX_SELECTOR_NODES: usize>(
        &mut self,
    ) -> Option<Selector<'a, MAX_SELECTOR_NODES>> {
        let attribute = self.read_identifier();
        let op = self
            .stream
            .current_cpy()
            .map(asm_core::selector_attr_op_kind)?;
        let ty = match op {
            1 => {
                self.stream.advance();
                Selector::Attribute(attribute)
            }
            2 => {
                self.stream.advance();
                let quote = self.stream.current_cpy().filter(|&c| asm_core::is_quote(c));
                if quote.is_some() {
                    self.stream.advance();
                }
                let value = self.read_identifier();
                if let Some(quote) = quote {
                    // Only require the given quote if the value starts with a quote
                    self.stream.expect_and_skip(quote)?;
                }
                self.stream.expect_and_skip(b']')?;
                Selector::AttributeValue(attribute, value)
            }
            c @ (3..=6) => {
                self.stream.advance();
                self.stream.expect_and_skip(b'=')?;
                let quote = self.stream.current_cpy().filter(|&c| asm_core::is_quote(c));
                if quote.is_some() {
                    self.stream.advance();
                }
                let value = self.read_identifier();
                if let Some(quote) = quote {
                    // Only require the given quote if the value starts with a quote
                    self.stream.expect_and_skip(quote)?;
                }
                self.stream.expect_and_skip(b']')?;
                match c {
                    3 => Selector::AttributeValueWhitespacedContains(attribute, value),
                    4 => Selector::AttributeValueStartsWith(attribute, value),
                    5 => Selector::AttributeValueEndsWith(attribute, value),
                    6 => Selector::AttributeValueSubstring(attribute, value),
                    _ => unreachable!(),
                }
            }
            _ => return None,
        };
        Some(ty)
    }

    /// Parses a full selector
    pub fn selector(&mut self) -> Option<Selector<'a>> {
        self.skip_whitespaces();
        let tok = self.stream.current_cpy()?;

        let left = match asm_core::selector_token_kind(tok) {
            1 => {
                self.stream.advance();
                let id = self.read_identifier();
                Selector::Id(id)
            }
            2 => {
                self.stream.advance();
                let class = self.read_identifier();
                Selector::Class(class)
            }
            3 => {
                self.stream.advance();
                Selector::All
            }
            4 => {
                self.stream.advance();
                self.parse_attribute::<0>()?
            }
            5 => {
                let tag = self.read_identifier();
                Selector::Tag(tag)
            }
            _ => return None,
        };

        self.parse_combinator(left)
    }
}