crates/editor/src/display_map.rs 🔗
@@ -1,5 +1,6 @@
mod block_map;
mod fold_map;
+mod patch;
mod tab_map;
mod wrap_map;
WIP
Antonio Scandurra created
Change summary
crates/editor/src/display_map.rs | 1
crates/editor/src/display_map/patch.rs | 138 +++++++++++++++++++++++++
crates/editor/src/display_map/wrap_map.rs | 49 ++++++++
3 files changed, 188 insertions(+)
Detailed changes
crates/editor/src/display_map/patch.rs 🔗
@@ -0,0 +1,138 @@
+use std::mem;
+
+type Edit = buffer::Edit<u32>;
+
+#[derive(Default, Debug)]
+struct Patch(Vec<Edit>);
+
+impl Patch {
+ fn compose(&self, new: &Self) -> Patch {
+ let mut composed = Vec::new();
+ let mut new_edits = new.0.iter().cloned().peekable();
+ let mut old_delta = 0;
+ let mut new_delta = 0;
+ for mut old_edit in self.0.iter().cloned() {
+ let mut next_new_delta = new_delta;
+ while let Some(mut new_edit) = new_edits.peek().cloned() {
+ let new_edit_delta = new_edit.new.len() as i32 - new_edit.old.len() as i32;
+ if new_edit.old.end < old_edit.new.start {
+ new_edit.old.start = (new_edit.old.start as i32 - old_delta) as u32;
+ new_edit.old.end = (new_edit.old.end as i32 - old_delta) as u32;
+ new_edits.next();
+ new_delta += new_edit_delta;
+ next_new_delta += new_edit_delta;
+ composed.push(new_edit);
+ } else if new_edit.old.start <= old_edit.new.end {
+ if new_edit.old.start < old_edit.new.start {
+ old_edit.old.start -= old_edit.new.start - new_edit.old.start;
+ old_edit.new.start = new_edit.new.start;
+ }
+ if new_edit.old.end > old_edit.new.end {
+ old_edit.old.end += new_edit.old.end - old_edit.new.end;
+ old_edit.new.end = new_edit.old.end;
+ }
+
+ old_edit.new.end = (old_edit.new.end as i32 + new_edit_delta) as u32;
+ new_edits.next();
+ next_new_delta += new_edit_delta;
+ } else {
+ break;
+ }
+ }
+
+ old_edit.new.start = (old_edit.new.start as i32 + new_delta) as u32;
+ old_edit.new.end = (old_edit.new.end as i32 + new_delta) as u32;
+ old_delta += old_edit.new.len() as i32 - old_edit.old.len() as i32;
+ new_delta = next_new_delta;
+ composed.push(old_edit);
+ }
+ composed.extend(new_edits.map(|mut new_edit| {
+ new_edit.old.start = (new_edit.old.start as i32 - old_delta) as u32;
+ new_edit.old.end = (new_edit.old.end as i32 - old_delta) as u32;
+ new_edit
+ }));
+
+ Patch(composed)
+ }
+
+ fn invert(&mut self) -> &mut Self {
+ for edit in &mut self.0 {
+ mem::swap(&mut edit.old, &mut edit.new);
+ }
+ self
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use rand::prelude::*;
+ use std::env;
+
+ #[gpui::test(iterations = 1000, seed = 28)]
+ fn test_random(mut rng: StdRng) {
+ let operations = env::var("OPERATIONS")
+ .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
+ .unwrap_or(3);
+
+ let initial_chars = (0..rng.gen_range(0..=5))
+ .map(|_| rng.gen_range(b'a'..=b'z') as char)
+ .collect::<Vec<_>>();
+ let mut final_chars = initial_chars.clone();
+ let mut patches = Vec::new();
+
+ println!("initial chars: {:?}", initial_chars);
+ for _ in 0..operations {
+ let end = rng.gen_range(0..=final_chars.len());
+ let start = rng.gen_range(0..=end);
+ let mut len = rng.gen_range(0..=3);
+ if start == end && len == 0 {
+ len += 1;
+ }
+ let new_chars = (0..len)
+ .map(|_| rng.gen_range(b'a'..=b'z') as char)
+ .collect::<Vec<_>>();
+ println!(
+ "editing {:?}: {:?}",
+ start..end,
+ new_chars.iter().collect::<String>()
+ );
+
+ let patch = Patch(vec![Edit {
+ old: start as u32..end as u32,
+ new: start as u32..start as u32 + new_chars.len() as u32,
+ }]);
+ if patches.is_empty() || rng.gen() {
+ println!("pushing singleton patch: {:?}", patch.0);
+ patches.push(patch);
+ } else {
+ let patch = patches.pop().unwrap().compose(&patch);
+ println!("composed patches: {:?}", patch.0);
+ patches.push(patch);
+ }
+ final_chars.splice(start..end, new_chars);
+ }
+
+ println!("final chars: {:?}", final_chars);
+ println!("final patches: {:?}", patches);
+
+ let mut composed = Patch::default();
+ for patch in patches {
+ println!("composing patches {:?} and {:?}", composed, patch);
+ composed = composed.compose(&patch);
+ println!("composed {:?}", composed);
+ }
+ println!("composed edits: {:?}", composed);
+ let mut chars = initial_chars.clone();
+ for edit in composed.0 {
+ chars.splice(
+ edit.new.start as usize..edit.new.start as usize + edit.old.len(),
+ final_chars[edit.new.start as usize..edit.new.end as usize]
+ .iter()
+ .copied(),
+ );
+ }
+
+ assert_eq!(chars, final_chars);
+ }
+}
crates/editor/src/display_map/wrap_map.rs 🔗
@@ -361,6 +361,55 @@ impl Patch {
// self.ranges = new_ranges;
}
+ fn compose2(&self, new: &Self) -> Patch {
+ let mut composed = Vec::new();
+ let mut new_edits = new.0.iter().cloned().peekable();
+ let mut old_delta = 0;
+ let mut new_delta = 0;
+ for mut old_edit in self.0.iter().cloned() {
+ let mut next_new_delta = new_delta;
+ while let Some(mut new_edit) = new_edits.peek().cloned() {
+ let new_edit_delta = new_edit.new.len() as i32 - new_edit.old.len() as i32;
+ if new_edit.old.end < old_edit.new.start {
+ new_edit.old.start = (new_edit.old.start as i32 - old_delta) as u32;
+ new_edit.old.end = (new_edit.old.end as i32 - old_delta) as u32;
+ new_edits.next();
+ new_delta += new_edit_delta;
+ next_new_delta += new_edit_delta;
+ composed.push(new_edit);
+ } else if new_edit.old.start <= old_edit.new.end {
+ if new_edit.old.start < old_edit.new.start {
+ old_edit.old.start -= old_edit.new.start - new_edit.old.start;
+ old_edit.new.start = new_edit.new.start;
+ }
+ if new_edit.old.end > old_edit.new.end {
+ old_edit.old.end += new_edit.old.end - old_edit.new.end;
+ old_edit.new.end = new_edit.old.end;
+ }
+
+ old_edit.new.end = (old_edit.new.end as i32 + new_edit_delta) as u32;
+ new_edits.next();
+ next_new_delta += new_edit_delta;
+ } else {
+ break;
+ }
+ }
+
+ old_edit.new.start = (old_edit.new.start as i32 + new_delta) as u32;
+ old_edit.new.end = (old_edit.new.end as i32 + new_delta) as u32;
+ old_delta += old_edit.new.len() as i32 - old_edit.old.len() as i32;
+ new_delta = next_new_delta;
+ composed.push(old_edit);
+ }
+ composed.extend(new_edits.map(|mut new_edit| {
+ new_edit.old.start = (new_edit.old.start as i32 - old_delta) as u32;
+ new_edit.old.end = (new_edit.old.end as i32 - old_delta) as u32;
+ new_edit
+ }));
+
+ Patch(composed)
+ }
+
fn invert(&mut self) -> &mut Self {
for edit in &mut self.0 {
mem::swap(&mut edit.old, &mut edit.new);