Parse escape characters properly

This commit is contained in:
Lewis Dale 2023-01-02 18:46:20 +00:00
parent 8edf1b9595
commit 9f55bef238
2 changed files with 33 additions and 25 deletions

View File

@ -1,25 +1,33 @@
use nom::{
bytes::complete::{tag, take_until, escaped},
character::{complete::{u32 as ccu32, one_of}, streaming::none_of},
combinator::map,
branch::alt,
bytes::complete::{escaped_transform, tag, take_until},
character::{
complete::{u32 as ccu32},
streaming::none_of,
},
combinator::{map, value},
sequence::{delimited, terminated, tuple},
IResult,
};
pub type Line<'a> = (u32, Command<'a>);
pub type Line = (u32, Command);
#[derive(Debug, PartialEq, Eq)]
pub enum Command<'a> {
Print(&'a str),
pub enum Command {
Print(String),
None,
}
fn read_string(i: &str) -> IResult<&str, &str> {
fn read_string(i: &str) -> IResult<&str, String> {
// take_until("\"")(i)
delimited(
tag("\""),
escaped(none_of("\\\""), '\\', one_of("\"\\")),
tag("\"")
escaped_transform(
none_of("\\\""),
'\\',
alt((value("\\", tag("\\")), value("\"", tag("\"")))),
),
tag("\""),
)(i)
}
@ -45,7 +53,7 @@ mod tests {
#[test]
fn it_parses_a_print_command() {
let input = "10 PRINT \"Hello, world\"";
let expected = (10, super::Command::Print("Hello, world"));
let expected = (10, super::Command::Print(String::from("Hello, world")));
let (_, result) = super::parse_line(input).unwrap();
assert_eq!(expected, result);
@ -55,13 +63,13 @@ mod tests {
fn it_reads_a_string() {
let input = r#""Hello, \"World\"""#;
let (_, output) = super::read_string(input).unwrap();
assert_eq!(r#"Hello, \"World\""#, output);
assert_eq!(r#"Hello, "World""#, output);
}
#[test]
fn it_parses_a_print_command_with_escaped_quotes() {
let input = r#"10 PRINT "Hello, \"world\"""#;
let expected = (10, super::Command::Print(r#"Hello, \"world\""#));
let expected = (10, super::Command::Print(String::from(r#"Hello, "world""#)));
let (_, result) = super::parse_line(input).unwrap();
assert_eq!(expected, result);

View File

@ -8,7 +8,7 @@ fn main() {
let (_, (_, command)) = basic::parse_line(lines).unwrap();
match command {
basic::Command::Print(input) => {
println!("{}", input.replace("\\", ""));
println!("{}", input);
}
_ => {
panic!("Command not recognised");