aboutsummaryrefslogtreecommitdiff
path: root/crates/libsyntax2/src/lexer/strings.rs
blob: a6da97d47e1b81d15cfc39ebd9734f8ff2348bd2 (plain)
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
use SyntaxKind::{self, *};

use lexer::ptr::Ptr;

pub(crate) fn is_string_literal_start(c: char, c1: Option<char>, c2: Option<char>) -> bool {
    match (c, c1, c2) {
        ('r', Some('"'), _)
        | ('r', Some('#'), _)
        | ('b', Some('"'), _)
        | ('b', Some('\''), _)
        | ('b', Some('r'), Some('"'))
        | ('b', Some('r'), Some('#')) => true,
        _ => false,
    }
}

pub(crate) fn scan_char(ptr: &mut Ptr) {
    while let Some(c) = ptr.next() {
        match c {
            '\\' => {
                ptr.bump();
                if ptr.next_is('\\') || ptr.next_is('\'') {
                    ptr.bump();
                }
            }
            '\'' => {
                ptr.bump();
                return;
            }
            '\n' => return,
            _ => {
                ptr.bump();
            }
        }
    }
}

pub(crate) fn scan_byte_char_or_string(ptr: &mut Ptr) -> SyntaxKind {
    // unwrapping and not-exhaustive match are ok
    // because of string_literal_start
    let c = ptr.bump().unwrap();
    match c {
        '\'' => {
            scan_byte(ptr);
            BYTE
        }
        '"' => {
            scan_byte_string(ptr);
            BYTE_STRING
        }
        'r' => {
            scan_raw_byte_string(ptr);
            RAW_BYTE_STRING
        }
        _ => unreachable!(),
    }
}

pub(crate) fn scan_string(ptr: &mut Ptr) {
    while let Some(c) = ptr.next() {
        match c {
            '\\' => {
                ptr.bump();
                if ptr.next_is('\\') || ptr.next_is('"') {
                    ptr.bump();
                }
            }
            '"' => {
                ptr.bump();
                return;
            }
            _ => {
                ptr.bump();
            },
        }
    }
}

pub(crate) fn scan_raw_string(ptr: &mut Ptr) {
    let mut hashes = 0;
    while ptr.next_is('#') {
        hashes += 1;
        ptr.bump();
    }
    if !ptr.next_is('"') {
        return;
    }
    ptr.bump();

    while let Some(c) = ptr.bump() {
        if c == '"' {
            let mut hashes_left = hashes;
            while ptr.next_is('#') && hashes_left > 0{
                hashes_left -= 1;
                ptr.bump();
            }
            if hashes_left == 0 {
                return;
            }
        }
    }
}

fn scan_byte(ptr: &mut Ptr) {
    if ptr.next_is('\'') {
        ptr.bump();
        return;
    }
    ptr.bump();
    if ptr.next_is('\'') {
        ptr.bump();
        return;
    }
}

fn scan_byte_string(ptr: &mut Ptr) {
    while let Some(c) = ptr.bump() {
        if c == '"' {
            return;
        }
    }
}

fn scan_raw_byte_string(ptr: &mut Ptr) {
    if !ptr.next_is('"') {
        return;
    }
    ptr.bump();

    while let Some(c) = ptr.bump() {
        if c == '"' {
            return;
        }
    }
}