syntax_parser_generator/readers/
byte_array_reader.rs

1use crate::readers::address_based::{AddressBasedReader, AddressSpace};
2
3pub struct ByteArrayAddressSpace {
4    data: Box<[u8]>,
5}
6
7impl ByteArrayAddressSpace {
8    fn from_string(data: String) -> Self {
9        ByteArrayAddressSpace {
10            data: data.into_bytes().into_boxed_slice(),
11        }
12    }
13}
14
15impl AddressSpace<u8> for ByteArrayAddressSpace {
16    fn read_at(&self, address: usize) -> Option<u8> {
17        self.data.get(address).copied()
18    }
19}
20
21/// Implementation of the [Reader](crate::readers::Reader) interface for accessing an in-memory
22/// array of bytes.
23pub type ByteArrayReader = AddressBasedReader<u8, ByteArrayAddressSpace>;
24
25impl ByteArrayReader {
26    /// Creates a new [Reader](crate::readers::Reader) for accessing the sequence of bytes in a
27    /// given [String].
28    pub fn from_string(data: String) -> ByteArrayReader {
29        let address_space = ByteArrayAddressSpace::from_string(data);
30        AddressBasedReader::raw_new(address_space)
31    }
32
33    /// Creates a new [Reader](crate::readers::Reader) for accessing the sequence of bytes in a
34    /// string, copied from the given string-slice.
35    pub fn from_string_slice(data: &str) -> Self {
36        Self::from_string(String::from(data))
37    }
38}
39
40#[cfg(test)]
41mod tests {
42    use crate::readers::Reader;
43
44    use super::*;
45
46    #[test]
47    fn test_reading() {
48        let mut reader = ByteArrayReader::from_string("Hi, this is data".to_string());
49        assert_eq!(reader.read_next(), Some('H' as u8));
50        assert_eq!(reader.read_next(), Some('i' as u8));
51        assert_eq!(reader.read_next(), Some(',' as u8));
52    }
53
54    #[test]
55    fn test_sequence_extraction() {
56        let mut reader = ByteArrayReader::from_string("Hi, this is data".to_string());
57        reader.read_next();
58        reader.read_next();
59        reader.read_next();
60        reader.read_next();
61        reader.set_head();
62        reader.read_next();
63        reader.read_next();
64        reader.read_next();
65        reader.read_next();
66        reader.set_tail();
67        assert_eq!(
68            String::from_utf8(reader.get_sequence().collect()).unwrap(),
69            "this".to_string(),
70        );
71    }
72
73    #[test]
74    fn test_reset_to_tail() {
75        let mut reader = ByteArrayReader::from_string("Hi, this is data".to_string());
76        reader.set_tail();
77        reader.read_next();
78        reader.restart_from_tail();
79        assert_eq!(reader.read_next(), Some('H' as u8));
80    }
81}
syntax_parser_generator/readers/byte_array_reader.rs

syntax_parser_generator/readers/
byte_array_reader.rs
