Files
another-boids-in-rust/vendor/cosmic-text/src/line_ending.rs

99 lines
2.7 KiB
Rust

use core::ops::Range;
/// Line ending
#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
pub enum LineEnding {
/// Use `\n` for line ending (POSIX-style)
#[default]
Lf,
/// Use `\r\n` for line ending (Windows-style)
CrLf,
/// Use `\r` for line ending (many legacy systems)
Cr,
/// Use `\n\r` for line ending (some legacy systems)
LfCr,
/// No line ending
None,
}
impl LineEnding {
/// Get the line ending as a str
pub fn as_str(&self) -> &'static str {
match self {
Self::Lf => "\n",
Self::CrLf => "\r\n",
Self::Cr => "\r",
Self::LfCr => "\n\r",
Self::None => "",
}
}
}
/// Iterator over lines terminated by [`LineEnding`]
#[derive(Debug)]
pub struct LineIter<'a> {
string: &'a str,
start: usize,
end: usize,
}
impl<'a> LineIter<'a> {
/// Create an iterator of lines in a string slice
pub fn new(string: &'a str) -> Self {
Self {
string,
start: 0,
end: string.len(),
}
}
}
impl Iterator for LineIter<'_> {
type Item = (Range<usize>, LineEnding);
fn next(&mut self) -> Option<Self::Item> {
let start = self.start;
match self.string[start..self.end].find(['\r', '\n']) {
Some(i) => {
let end = start + i;
self.start = end;
let after = &self.string[end..];
let ending = if after.starts_with("\r\n") {
LineEnding::CrLf
} else if after.starts_with("\n\r") {
LineEnding::LfCr
} else if after.starts_with("\n") {
LineEnding::Lf
} else if after.starts_with("\r") {
LineEnding::Cr
} else {
//TODO: this should not be possible
LineEnding::None
};
self.start += ending.as_str().len();
Some((start..end, ending))
}
None => {
if self.start < self.end {
self.start = self.end;
Some((start..self.end, LineEnding::None))
} else {
None
}
}
}
}
}
//TODO: DoubleEndedIterator
#[test]
fn test_line_iter() {
let string = "LF\nCRLF\r\nCR\rLFCR\n\rNONE";
let mut iter = LineIter::new(string);
assert_eq!(iter.next(), Some((0..2, LineEnding::Lf)));
assert_eq!(iter.next(), Some((3..7, LineEnding::CrLf)));
assert_eq!(iter.next(), Some((9..11, LineEnding::Cr)));
assert_eq!(iter.next(), Some((12..16, LineEnding::LfCr)));
assert_eq!(iter.next(), Some((18..22, LineEnding::None)));
}