ZIm/crates/assistant/src/omit_ranges.rs

101 lines
3.3 KiB
Rust

use rope::Rope;
use std::{cmp::Ordering, ops::Range};
pub(crate) fn text_in_range_omitting_ranges(
rope: &Rope,
range: Range<usize>,
omit_ranges: &[Range<usize>],
) -> String {
let mut content = String::with_capacity(range.len());
let mut omit_ranges = omit_ranges
.iter()
.skip_while(|omit_range| omit_range.end <= range.start)
.peekable();
let mut offset = range.start;
let mut chunks = rope.chunks_in_range(range.clone());
while let Some(chunk) = chunks.next() {
if let Some(omit_range) = omit_ranges.peek() {
match offset.cmp(&omit_range.start) {
Ordering::Less => {
let max_len = omit_range.start - offset;
if chunk.len() < max_len {
content.push_str(chunk);
offset += chunk.len();
} else {
content.push_str(&chunk[..max_len]);
chunks.seek(omit_range.end.min(range.end));
offset = omit_range.end;
omit_ranges.next();
}
}
Ordering::Equal | Ordering::Greater => {
chunks.seek(omit_range.end.min(range.end));
offset = omit_range.end;
omit_ranges.next();
}
}
} else {
content.push_str(chunk);
offset += chunk.len();
}
}
content
}
#[cfg(test)]
mod tests {
use super::*;
use rand::{rngs::StdRng, Rng as _};
use util::RandomCharIter;
#[gpui::test(iterations = 100)]
fn test_text_in_range_omitting_ranges(mut rng: StdRng) {
let text = RandomCharIter::new(&mut rng).take(1024).collect::<String>();
let rope = Rope::from(text.as_str());
let mut start = rng.gen_range(0..=text.len() / 2);
let mut end = rng.gen_range(text.len() / 2..=text.len());
while !text.is_char_boundary(start) {
start -= 1;
}
while !text.is_char_boundary(end) {
end += 1;
}
let range = start..end;
let mut ix = 0;
let mut omit_ranges = Vec::new();
for _ in 0..rng.gen_range(0..10) {
let mut start = rng.gen_range(ix..=text.len());
while !text.is_char_boundary(start) {
start += 1;
}
let mut end = rng.gen_range(start..=text.len());
while !text.is_char_boundary(end) {
end += 1;
}
omit_ranges.push(start..end);
ix = end;
if ix == text.len() {
break;
}
}
let mut expected_text = text[range.clone()].to_string();
for omit_range in omit_ranges.iter().rev() {
let start = omit_range
.start
.saturating_sub(range.start)
.min(range.len());
let end = omit_range.end.saturating_sub(range.start).min(range.len());
expected_text.replace_range(start..end, "");
}
assert_eq!(
text_in_range_omitting_ranges(&rope, range.clone(), &omit_ranges),
expected_text,
"text: {text:?}\nrange: {range:?}\nomit_ranges: {omit_ranges:?}"
);
}
}