ZIm/zed/src/editor/display_map/fold_map.rs
Nathan Sobo afb623b6b5 Make Workspace::open_entry2, which returns a dyn ItemViewHandle
Co-Authored-By: Max Brunsfeld <maxbrunsfeld@gmail.com>
2021-05-03 16:25:18 -06:00

725 lines
25 KiB
Rust

use super::{
buffer, Anchor, AnchorRangeExt, Buffer, DisplayPoint, Edit, Point, TextSummary, ToOffset,
};
use crate::{
sum_tree::{self, Cursor, SumTree},
util::find_insertion_index,
};
use anyhow::{anyhow, Result};
use gpui::{AppContext, ModelHandle};
use std::{
cmp::{self, Ordering},
iter::Take,
ops::Range,
};
use sum_tree::{Dimension, SeekBias};
pub struct FoldMap {
buffer: ModelHandle<Buffer>,
transforms: SumTree<Transform>,
folds: Vec<Range<Anchor>>,
}
impl FoldMap {
pub fn new(buffer: ModelHandle<Buffer>, app: &AppContext) -> Self {
let text_summary = buffer.read(app).text_summary();
Self {
buffer,
folds: Vec::new(),
transforms: SumTree::from_item(Transform {
summary: TransformSummary {
buffer: text_summary.clone(),
display: text_summary,
},
display_text: None,
}),
}
}
pub fn buffer_rows(&self, start_row: u32) -> Result<BufferRows> {
if start_row > self.transforms.summary().display.lines.row {
return Err(anyhow!("invalid display row {}", start_row));
}
let display_point = Point::new(start_row, 0);
let mut cursor = self.transforms.cursor();
cursor.seek(&DisplayPoint(display_point), SeekBias::Left);
Ok(BufferRows {
display_point,
cursor,
})
}
pub fn len(&self) -> usize {
self.transforms.summary().display.chars
}
pub fn line_len(&self, row: u32, ctx: &AppContext) -> Result<u32> {
let line_start = self.to_display_offset(DisplayPoint::new(row, 0), ctx)?.0;
let line_end = if row >= self.max_point().row() {
self.len()
} else {
self.to_display_offset(DisplayPoint::new(row + 1, 0), ctx)?
.0
- 1
};
Ok((line_end - line_start) as u32)
}
pub fn chars_at<'a>(&'a self, point: DisplayPoint, app: &'a AppContext) -> Result<Chars<'a>> {
let offset = self.to_display_offset(point, app)?;
let mut cursor = self.transforms.cursor();
cursor.seek(&offset, SeekBias::Right);
let buffer = self.buffer.read(app);
Ok(Chars {
cursor,
offset: offset.0,
buffer,
buffer_chars: None,
})
}
pub fn max_point(&self) -> DisplayPoint {
DisplayPoint(self.transforms.summary().display.lines)
}
pub fn rightmost_point(&self) -> DisplayPoint {
DisplayPoint(self.transforms.summary().display.rightmost_point)
}
pub fn fold<T: ToOffset>(
&mut self,
ranges: impl IntoIterator<Item = Range<T>>,
app: &AppContext,
) -> Result<()> {
let mut edits = Vec::new();
let buffer = self.buffer.read(app);
for range in ranges.into_iter() {
let start = range.start.to_offset(buffer)?;
let end = range.end.to_offset(buffer)?;
edits.push(Edit {
old_range: start..end,
new_range: start..end,
});
let fold = buffer.anchor_after(start)?..buffer.anchor_before(end)?;
let ix = find_insertion_index(&self.folds, |probe| probe.cmp(&fold, buffer))?;
self.folds.insert(ix, fold);
}
edits.sort_unstable_by(|a, b| {
a.old_range
.start
.cmp(&b.old_range.start)
.then_with(|| b.old_range.end.cmp(&a.old_range.end))
});
self.apply_edits(&edits, app)?;
Ok(())
}
pub fn unfold<T: ToOffset>(
&mut self,
ranges: impl IntoIterator<Item = Range<T>>,
app: &AppContext,
) -> Result<()> {
let buffer = self.buffer.read(app);
let mut edits = Vec::new();
for range in ranges.into_iter() {
let start = buffer.anchor_before(range.start.to_offset(buffer)?)?;
let end = buffer.anchor_after(range.end.to_offset(buffer)?)?;
// Remove intersecting folds and add their ranges to edits that are passed to apply_edits
self.folds.retain(|fold| {
if fold.start.cmp(&end, buffer).unwrap() > Ordering::Equal
|| fold.end.cmp(&start, buffer).unwrap() < Ordering::Equal
{
true
} else {
let offset_range =
fold.start.to_offset(buffer).unwrap()..fold.end.to_offset(buffer).unwrap();
edits.push(Edit {
old_range: offset_range.clone(),
new_range: offset_range,
});
false
}
});
}
self.apply_edits(&edits, app)?;
Ok(())
}
pub fn is_line_folded(&self, display_row: u32) -> bool {
let mut cursor = self.transforms.cursor::<DisplayPoint, DisplayPoint>();
cursor.seek(&DisplayPoint::new(display_row, 0), SeekBias::Right);
while let Some(transform) = cursor.item() {
if transform.display_text.is_some() {
return true;
}
if cursor.end().row() == display_row {
cursor.next()
} else {
break;
}
}
false
}
pub fn to_display_offset(
&self,
point: DisplayPoint,
app: &AppContext,
) -> Result<DisplayOffset> {
let mut cursor = self.transforms.cursor::<DisplayPoint, TransformSummary>();
cursor.seek(&point, SeekBias::Right);
let overshoot = point.0 - cursor.start().display.lines;
let mut offset = cursor.start().display.chars;
if !overshoot.is_zero() {
let transform = cursor
.item()
.ok_or_else(|| anyhow!("display point {:?} is out of range", point))?;
assert!(transform.display_text.is_none());
let end_buffer_offset =
(cursor.start().buffer.lines + overshoot).to_offset(self.buffer.read(app))?;
offset += end_buffer_offset - cursor.start().buffer.chars;
}
Ok(DisplayOffset(offset))
}
pub fn to_buffer_point(&self, display_point: DisplayPoint) -> Point {
let mut cursor = self.transforms.cursor::<DisplayPoint, TransformSummary>();
cursor.seek(&display_point, SeekBias::Right);
let overshoot = display_point.0 - cursor.start().display.lines;
cursor.start().buffer.lines + overshoot
}
pub fn to_display_point(&self, point: Point) -> DisplayPoint {
let mut cursor = self.transforms.cursor::<Point, TransformSummary>();
cursor.seek(&point, SeekBias::Right);
let overshoot = point - cursor.start().buffer.lines;
DisplayPoint(cmp::min(
cursor.start().display.lines + overshoot,
cursor.end().display.lines,
))
}
pub fn apply_edits(&mut self, edits: &[Edit], app: &AppContext) -> Result<()> {
let buffer = self.buffer.read(app);
let mut edits = edits.iter().cloned().peekable();
let mut new_transforms = SumTree::new();
let mut cursor = self.transforms.cursor::<usize, usize>();
cursor.seek(&0, SeekBias::Right);
while let Some(mut edit) = edits.next() {
new_transforms.push_tree(cursor.slice(&edit.old_range.start, SeekBias::Left));
edit.new_range.start -= edit.old_range.start - cursor.start();
edit.old_range.start = *cursor.start();
cursor.seek(&edit.old_range.end, SeekBias::Right);
cursor.next();
let mut delta = edit.delta();
loop {
edit.old_range.end = *cursor.start();
if let Some(next_edit) = edits.peek() {
if next_edit.old_range.start > edit.old_range.end {
break;
}
let next_edit = edits.next().unwrap();
delta += next_edit.delta();
if next_edit.old_range.end > edit.old_range.end {
edit.old_range.end = next_edit.old_range.end;
cursor.seek(&edit.old_range.end, SeekBias::Right);
cursor.next();
}
} else {
break;
}
}
edit.new_range.end =
((edit.new_range.start + edit.old_extent()) as isize + delta) as usize;
let anchor = buffer.anchor_before(edit.new_range.start)?;
let folds_start =
find_insertion_index(&self.folds, |probe| probe.start.cmp(&anchor, buffer))?;
let mut folds = self.folds[folds_start..]
.iter()
.map(|fold| {
fold.start.to_offset(buffer).unwrap()..fold.end.to_offset(buffer).unwrap()
})
.peekable();
while folds
.peek()
.map_or(false, |fold| fold.start < edit.new_range.end)
{
let mut fold = folds.next().unwrap();
let sum = new_transforms.summary();
assert!(fold.start >= sum.buffer.chars);
while folds
.peek()
.map_or(false, |next_fold| next_fold.start <= fold.end)
{
let next_fold = folds.next().unwrap();
if next_fold.end > fold.end {
fold.end = next_fold.end;
}
}
if fold.start > sum.buffer.chars {
let text_summary = buffer.text_summary_for_range(sum.buffer.chars..fold.start);
new_transforms.push(Transform {
summary: TransformSummary {
display: text_summary.clone(),
buffer: text_summary,
},
display_text: None,
});
}
if fold.end > fold.start {
new_transforms.push(Transform {
summary: TransformSummary {
display: TextSummary {
chars: 1,
bytes: ''.len_utf8(),
lines: Point::new(0, 1),
first_line_len: 1,
rightmost_point: Point::new(0, 1),
},
buffer: buffer.text_summary_for_range(fold.start..fold.end),
},
display_text: Some('…'),
});
}
}
let sum = new_transforms.summary();
if sum.buffer.chars < edit.new_range.end {
let text_summary =
buffer.text_summary_for_range(sum.buffer.chars..edit.new_range.end);
new_transforms.push(Transform {
summary: TransformSummary {
display: text_summary.clone(),
buffer: text_summary,
},
display_text: None,
});
}
}
new_transforms.push_tree(cursor.suffix());
if new_transforms.is_empty() {
let text_summary = buffer.text_summary();
new_transforms.push(Transform {
summary: TransformSummary {
display: text_summary.clone(),
buffer: text_summary,
},
display_text: None,
});
}
drop(cursor);
self.transforms = new_transforms;
Ok(())
}
}
#[derive(Clone, Debug, Default, Eq, PartialEq)]
struct Transform {
summary: TransformSummary,
display_text: Option<char>,
}
#[derive(Clone, Debug, Default, Eq, PartialEq)]
struct TransformSummary {
display: TextSummary,
buffer: TextSummary,
}
impl sum_tree::Item for Transform {
type Summary = TransformSummary;
fn summary(&self) -> Self::Summary {
self.summary.clone()
}
}
impl<'a> std::ops::AddAssign<&'a Self> for TransformSummary {
fn add_assign(&mut self, other: &'a Self) {
self.buffer += &other.buffer;
self.display += &other.display;
}
}
impl<'a> Dimension<'a, TransformSummary> for TransformSummary {
fn add_summary(&mut self, summary: &'a TransformSummary) {
*self += summary;
}
}
pub struct BufferRows<'a> {
cursor: Cursor<'a, Transform, DisplayPoint, TransformSummary>,
display_point: Point,
}
impl<'a> Iterator for BufferRows<'a> {
type Item = u32;
fn next(&mut self) -> Option<Self::Item> {
while self.display_point > self.cursor.end().display.lines {
self.cursor.next();
if self.cursor.item().is_none() {
// TODO: Return a bool from next?
break;
}
}
if self.cursor.item().is_some() {
let overshoot = self.display_point - self.cursor.start().display.lines;
let buffer_point = self.cursor.start().buffer.lines + overshoot;
self.display_point.row += 1;
Some(buffer_point.row)
} else {
None
}
}
}
pub struct Chars<'a> {
cursor: Cursor<'a, Transform, DisplayOffset, TransformSummary>,
offset: usize,
buffer: &'a Buffer,
buffer_chars: Option<Take<buffer::CharIter<'a>>>,
}
impl<'a> Iterator for Chars<'a> {
type Item = char;
fn next(&mut self) -> Option<Self::Item> {
if let Some(c) = self.buffer_chars.as_mut().and_then(|chars| chars.next()) {
self.offset += 1;
return Some(c);
}
if self.offset == self.cursor.end().display.chars {
self.cursor.next();
}
self.cursor.item().and_then(|transform| {
if let Some(c) = transform.display_text {
self.offset += 1;
Some(c)
} else {
let overshoot = self.offset - self.cursor.start().display.chars;
let buffer_start = self.cursor.start().buffer.chars + overshoot;
let char_count = self.cursor.end().buffer.chars - buffer_start;
self.buffer_chars =
Some(self.buffer.chars_at(buffer_start).unwrap().take(char_count));
self.next()
}
})
}
}
impl<'a> Dimension<'a, TransformSummary> for DisplayPoint {
fn add_summary(&mut self, summary: &'a TransformSummary) {
self.0 += &summary.display.lines;
}
}
#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
pub struct DisplayOffset(usize);
impl<'a> Dimension<'a, TransformSummary> for DisplayOffset {
fn add_summary(&mut self, summary: &'a TransformSummary) {
self.0 += &summary.display.chars;
}
}
impl<'a> Dimension<'a, TransformSummary> for Point {
fn add_summary(&mut self, summary: &'a TransformSummary) {
*self += &summary.buffer.lines;
}
}
impl<'a> Dimension<'a, TransformSummary> for usize {
fn add_summary(&mut self, summary: &'a TransformSummary) {
*self += &summary.buffer.chars;
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::test::sample_text;
use gpui::App;
#[test]
fn test_basic_folds() {
App::test((), |app| {
let buffer = app.add_model(|ctx| Buffer::new(0, sample_text(5, 6)));
let mut map = FoldMap::new(buffer.clone(), app.as_ref());
map.fold(
vec![
Point::new(0, 2)..Point::new(2, 2),
Point::new(2, 4)..Point::new(4, 1),
],
app.as_ref(),
)
.unwrap();
assert_eq!(map.text(app.as_ref()), "aa…cc…eeeee");
let edits = buffer.update(app, |buffer, ctx| {
let start_version = buffer.version.clone();
buffer
.edit(
vec![
Point::new(0, 0)..Point::new(0, 1),
Point::new(2, 3)..Point::new(2, 3),
],
"123",
Some(ctx),
)
.unwrap();
buffer.edits_since(start_version).collect::<Vec<_>>()
});
map.apply_edits(&edits, app.as_ref()).unwrap();
assert_eq!(map.text(app.as_ref()), "123a…c123c…eeeee");
let edits = buffer.update(app, |buffer, ctx| {
let start_version = buffer.version.clone();
buffer
.edit(Some(Point::new(2, 6)..Point::new(4, 3)), "456", Some(ctx))
.unwrap();
buffer.edits_since(start_version).collect::<Vec<_>>()
});
map.apply_edits(&edits, app.as_ref()).unwrap();
assert_eq!(map.text(app.as_ref()), "123a…c123456eee");
map.unfold(Some(Point::new(0, 4)..Point::new(0, 4)), app.as_ref())
.unwrap();
assert_eq!(map.text(app.as_ref()), "123aaaaa\nbbbbbb\nccc123456eee");
});
}
#[test]
fn test_overlapping_folds() {
App::test((), |app| {
let buffer = app.add_model(|_| Buffer::new(0, sample_text(5, 6)));
let mut map = FoldMap::new(buffer.clone(), app.as_ref());
map.fold(
vec![
Point::new(0, 2)..Point::new(2, 2),
Point::new(0, 4)..Point::new(1, 0),
Point::new(1, 2)..Point::new(3, 2),
Point::new(3, 1)..Point::new(4, 1),
],
app.as_ref(),
)
.unwrap();
assert_eq!(map.text(app.as_ref()), "aa…eeeee");
})
}
#[test]
fn test_merging_folds_via_edit() {
App::test((), |app| {
let buffer = app.add_model(|_| Buffer::new(0, sample_text(5, 6)));
let mut map = FoldMap::new(buffer.clone(), app.as_ref());
map.fold(
vec![
Point::new(0, 2)..Point::new(2, 2),
Point::new(3, 1)..Point::new(4, 1),
],
app.as_ref(),
)
.unwrap();
assert_eq!(map.text(app.as_ref()), "aa…cccc\nd…eeeee");
let edits = buffer.update(app, |buffer, ctx| {
let start_version = buffer.version.clone();
buffer
.edit(Some(Point::new(2, 2)..Point::new(3, 1)), "", Some(ctx))
.unwrap();
buffer.edits_since(start_version).collect::<Vec<_>>()
});
map.apply_edits(&edits, app.as_ref()).unwrap();
assert_eq!(map.text(app.as_ref()), "aa…eeeee");
});
}
#[test]
fn test_random_folds() {
use crate::editor::ToPoint;
use crate::util::RandomCharIter;
use rand::prelude::*;
use std::env;
let iterations = env::var("ITERATIONS")
.map(|i| i.parse().expect("invalid `ITERATIONS` variable"))
.unwrap_or(100);
let seed_range = if let Ok(seed) = env::var("SEED") {
let seed = seed.parse().expect("invalid `SEED` variable");
seed..seed + 1
} else {
0..iterations
};
for seed in seed_range {
println!("{:?}", seed);
let mut rng = StdRng::seed_from_u64(seed);
App::test((), |app| {
let buffer = app.add_model(|_| {
let len = rng.gen_range(0..10);
let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
Buffer::new(0, text)
});
let mut map = FoldMap::new(buffer.clone(), app.as_ref());
{
let buffer = buffer.read(app);
let fold_count = rng.gen_range(0..10);
let mut fold_ranges: Vec<Range<usize>> = Vec::new();
for _ in 0..fold_count {
let end = rng.gen_range(0..buffer.len() + 1);
let start = rng.gen_range(0..end + 1);
fold_ranges.push(start..end);
}
map.fold(fold_ranges, app.as_ref()).unwrap();
let mut expected_text = buffer.text();
for fold_range in map.merged_fold_ranges(app.as_ref()).into_iter().rev() {
expected_text.replace_range(fold_range.start..fold_range.end, "");
}
assert_eq!(map.text(app.as_ref()), expected_text);
for fold_range in map.merged_fold_ranges(app.as_ref()) {
let display_point =
map.to_display_point(fold_range.start.to_point(buffer).unwrap());
assert!(map.is_line_folded(display_point.row()));
}
}
let edits = buffer.update(app, |buffer, ctx| {
let start_version = buffer.version.clone();
let edit_count = rng.gen_range(1..10);
buffer.randomly_edit(&mut rng, edit_count, Some(ctx));
buffer.edits_since(start_version).collect::<Vec<_>>()
});
map.apply_edits(&edits, app.as_ref()).unwrap();
let buffer = map.buffer.read(app);
let mut expected_text = buffer.text();
let mut expected_buffer_rows = Vec::new();
let mut next_row = buffer.max_point().row;
for fold_range in map.merged_fold_ranges(app.as_ref()).into_iter().rev() {
let fold_start = buffer.point_for_offset(fold_range.start).unwrap();
let fold_end = buffer.point_for_offset(fold_range.end).unwrap();
expected_buffer_rows.extend((fold_end.row + 1..=next_row).rev());
next_row = fold_start.row;
expected_text.replace_range(fold_range.start..fold_range.end, "");
}
expected_buffer_rows.extend((0..=next_row).rev());
expected_buffer_rows.reverse();
assert_eq!(map.text(app.as_ref()), expected_text);
for (idx, buffer_row) in expected_buffer_rows.iter().enumerate() {
let display_row = map.to_display_point(Point::new(*buffer_row, 0)).row();
assert_eq!(
map.buffer_rows(display_row).unwrap().collect::<Vec<_>>(),
expected_buffer_rows[idx..],
);
}
});
}
}
#[test]
fn test_buffer_rows() {
App::test((), |app| {
let text = sample_text(6, 6) + "\n";
let buffer = app.add_model(|_| Buffer::new(0, text));
let mut map = FoldMap::new(buffer.clone(), app.as_ref());
map.fold(
vec![
Point::new(0, 2)..Point::new(2, 2),
Point::new(3, 1)..Point::new(4, 1),
],
app.as_ref(),
)
.unwrap();
assert_eq!(map.text(app.as_ref()), "aa…cccc\nd…eeeee\nffffff\n");
assert_eq!(
map.buffer_rows(0).unwrap().collect::<Vec<_>>(),
vec![0, 3, 5, 6]
);
assert_eq!(map.buffer_rows(3).unwrap().collect::<Vec<_>>(), vec![6]);
});
}
impl FoldMap {
fn text(&self, app: &AppContext) -> String {
self.chars_at(DisplayPoint(Point::zero()), app)
.unwrap()
.collect()
}
fn merged_fold_ranges(&self, app: &AppContext) -> Vec<Range<usize>> {
let buffer = self.buffer.read(app);
let mut fold_ranges = self
.folds
.iter()
.map(|fold| {
fold.start.to_offset(buffer).unwrap()..fold.end.to_offset(buffer).unwrap()
})
.peekable();
let mut merged_ranges = Vec::new();
while let Some(mut fold_range) = fold_ranges.next() {
while let Some(next_range) = fold_ranges.peek() {
if fold_range.end >= next_range.start {
if next_range.end > fold_range.end {
fold_range.end = next_range.end;
}
fold_ranges.next();
} else {
break;
}
}
if fold_range.end > fold_range.start {
merged_ranges.push(fold_range);
}
}
merged_ranges
}
}
}