Files
oak-gpui/crates/editor/src/display_map/tab_map.rs
T
Max Brunsfeld 6cdf4e98fc Re-export basic text types from text and language crates
Also avoid production dependencies on fs and rope in collab
2022-10-12 15:48:19 -07:00

572 lines
18 KiB
Rust

use super::{
fold_map::{self, FoldEdit, FoldPoint, FoldSnapshot},
TextHighlights,
};
use crate::MultiBufferSnapshot;
use language::{Chunk, Point};
use parking_lot::Mutex;
use std::{cmp, mem, num::NonZeroU32, ops::Range};
use sum_tree::Bias;
pub struct TabMap(Mutex<TabSnapshot>);
impl TabMap {
pub fn new(input: FoldSnapshot, tab_size: NonZeroU32) -> (Self, TabSnapshot) {
let snapshot = TabSnapshot {
fold_snapshot: input,
tab_size,
version: 0,
};
(Self(Mutex::new(snapshot.clone())), snapshot)
}
pub fn sync(
&self,
fold_snapshot: FoldSnapshot,
mut fold_edits: Vec<FoldEdit>,
tab_size: NonZeroU32,
) -> (TabSnapshot, Vec<TabEdit>) {
let mut old_snapshot = self.0.lock();
let mut new_snapshot = TabSnapshot {
fold_snapshot,
tab_size,
version: old_snapshot.version,
};
if old_snapshot.fold_snapshot.version != new_snapshot.fold_snapshot.version {
new_snapshot.version += 1;
}
let old_max_offset = old_snapshot.fold_snapshot.len();
let mut tab_edits = Vec::with_capacity(fold_edits.len());
if old_snapshot.tab_size == new_snapshot.tab_size {
for fold_edit in &mut fold_edits {
let mut delta = 0;
for chunk in old_snapshot.fold_snapshot.chunks(
fold_edit.old.end..old_max_offset,
false,
None,
) {
let patterns: &[_] = &['\t', '\n'];
if let Some(ix) = chunk.text.find(patterns) {
if &chunk.text[ix..ix + 1] == "\t" {
fold_edit.old.end.0 += delta + ix + 1;
fold_edit.new.end.0 += delta + ix + 1;
}
break;
}
delta += chunk.text.len();
}
}
let mut ix = 1;
while ix < fold_edits.len() {
let (prev_edits, next_edits) = fold_edits.split_at_mut(ix);
let prev_edit = prev_edits.last_mut().unwrap();
let edit = &next_edits[0];
if prev_edit.old.end >= edit.old.start {
prev_edit.old.end = edit.old.end;
prev_edit.new.end = edit.new.end;
fold_edits.remove(ix);
} else {
ix += 1;
}
}
for fold_edit in fold_edits {
let old_start = fold_edit.old.start.to_point(&old_snapshot.fold_snapshot);
let old_end = fold_edit.old.end.to_point(&old_snapshot.fold_snapshot);
let new_start = fold_edit.new.start.to_point(&new_snapshot.fold_snapshot);
let new_end = fold_edit.new.end.to_point(&new_snapshot.fold_snapshot);
tab_edits.push(TabEdit {
old: old_snapshot.to_tab_point(old_start)..old_snapshot.to_tab_point(old_end),
new: new_snapshot.to_tab_point(new_start)..new_snapshot.to_tab_point(new_end),
});
}
} else {
new_snapshot.version += 1;
tab_edits.push(TabEdit {
old: TabPoint::zero()..old_snapshot.max_point(),
new: TabPoint::zero()..new_snapshot.max_point(),
});
}
*old_snapshot = new_snapshot;
(old_snapshot.clone(), tab_edits)
}
}
#[derive(Clone)]
pub struct TabSnapshot {
pub fold_snapshot: FoldSnapshot,
pub tab_size: NonZeroU32,
pub version: usize,
}
impl TabSnapshot {
pub fn buffer_snapshot(&self) -> &MultiBufferSnapshot {
self.fold_snapshot.buffer_snapshot()
}
pub fn line_len(&self, row: u32) -> u32 {
let max_point = self.max_point();
if row < max_point.row() {
self.chunks(
TabPoint::new(row, 0)..TabPoint::new(row + 1, 0),
false,
None,
)
.map(|chunk| chunk.text.len() as u32)
.sum::<u32>()
- 1
} else {
max_point.column()
}
}
pub fn text_summary(&self) -> TextSummary {
self.text_summary_for_range(TabPoint::zero()..self.max_point())
}
pub fn text_summary_for_range(&self, range: Range<TabPoint>) -> TextSummary {
let input_start = self.to_fold_point(range.start, Bias::Left).0;
let input_end = self.to_fold_point(range.end, Bias::Right).0;
let input_summary = self
.fold_snapshot
.text_summary_for_range(input_start..input_end);
let mut first_line_chars = 0;
let line_end = if range.start.row() == range.end.row() {
range.end
} else {
self.max_point()
};
for c in self
.chunks(range.start..line_end, false, None)
.flat_map(|chunk| chunk.text.chars())
{
if c == '\n' {
break;
}
first_line_chars += 1;
}
let mut last_line_chars = 0;
if range.start.row() == range.end.row() {
last_line_chars = first_line_chars;
} else {
for _ in self
.chunks(TabPoint::new(range.end.row(), 0)..range.end, false, None)
.flat_map(|chunk| chunk.text.chars())
{
last_line_chars += 1;
}
}
TextSummary {
lines: range.end.0 - range.start.0,
first_line_chars,
last_line_chars,
longest_row: input_summary.longest_row,
longest_row_chars: input_summary.longest_row_chars,
}
}
pub fn chunks<'a>(
&'a self,
range: Range<TabPoint>,
language_aware: bool,
text_highlights: Option<&'a TextHighlights>,
) -> TabChunks<'a> {
let (input_start, expanded_char_column, to_next_stop) =
self.to_fold_point(range.start, Bias::Left);
let input_start = input_start.to_offset(&self.fold_snapshot);
let input_end = self
.to_fold_point(range.end, Bias::Right)
.0
.to_offset(&self.fold_snapshot);
let to_next_stop = if range.start.0 + Point::new(0, to_next_stop as u32) > range.end.0 {
(range.end.column() - range.start.column()) as usize
} else {
to_next_stop
};
TabChunks {
fold_chunks: self.fold_snapshot.chunks(
input_start..input_end,
language_aware,
text_highlights,
),
column: expanded_char_column,
output_position: range.start.0,
max_output_position: range.end.0,
tab_size: self.tab_size,
chunk: Chunk {
text: &SPACES[0..to_next_stop],
..Default::default()
},
skip_leading_tab: to_next_stop > 0,
}
}
pub fn buffer_rows(&self, row: u32) -> fold_map::FoldBufferRows {
self.fold_snapshot.buffer_rows(row)
}
#[cfg(test)]
pub fn text(&self) -> String {
self.chunks(TabPoint::zero()..self.max_point(), false, None)
.map(|chunk| chunk.text)
.collect()
}
pub fn max_point(&self) -> TabPoint {
self.to_tab_point(self.fold_snapshot.max_point())
}
pub fn clip_point(&self, point: TabPoint, bias: Bias) -> TabPoint {
self.to_tab_point(
self.fold_snapshot
.clip_point(self.to_fold_point(point, bias).0, bias),
)
}
pub fn to_tab_point(&self, input: FoldPoint) -> TabPoint {
let chars = self.fold_snapshot.chars_at(FoldPoint::new(input.row(), 0));
let expanded = Self::expand_tabs(chars, input.column() as usize, self.tab_size);
TabPoint::new(input.row(), expanded as u32)
}
pub fn to_fold_point(&self, output: TabPoint, bias: Bias) -> (FoldPoint, usize, usize) {
let chars = self.fold_snapshot.chars_at(FoldPoint::new(output.row(), 0));
let expanded = output.column() as usize;
let (collapsed, expanded_char_column, to_next_stop) =
Self::collapse_tabs(chars, expanded, bias, self.tab_size);
(
FoldPoint::new(output.row(), collapsed as u32),
expanded_char_column,
to_next_stop,
)
}
pub fn make_tab_point(&self, point: Point, bias: Bias) -> TabPoint {
self.to_tab_point(self.fold_snapshot.to_fold_point(point, bias))
}
pub fn to_point(&self, point: TabPoint, bias: Bias) -> Point {
self.to_fold_point(point, bias)
.0
.to_buffer_point(&self.fold_snapshot)
}
fn expand_tabs(
chars: impl Iterator<Item = char>,
column: usize,
tab_size: NonZeroU32,
) -> usize {
let mut expanded_chars = 0;
let mut expanded_bytes = 0;
let mut collapsed_bytes = 0;
for c in chars {
if collapsed_bytes == column {
break;
}
if c == '\t' {
let tab_size = tab_size.get() as usize;
let tab_len = tab_size - expanded_chars % tab_size;
expanded_bytes += tab_len;
expanded_chars += tab_len;
} else {
expanded_bytes += c.len_utf8();
expanded_chars += 1;
}
collapsed_bytes += c.len_utf8();
}
expanded_bytes
}
fn collapse_tabs(
chars: impl Iterator<Item = char>,
column: usize,
bias: Bias,
tab_size: NonZeroU32,
) -> (usize, usize, usize) {
let mut expanded_bytes = 0;
let mut expanded_chars = 0;
let mut collapsed_bytes = 0;
for c in chars {
if expanded_bytes >= column {
break;
}
if c == '\t' {
let tab_size = tab_size.get() as usize;
let tab_len = tab_size - (expanded_chars % tab_size);
expanded_chars += tab_len;
expanded_bytes += tab_len;
if expanded_bytes > column {
expanded_chars -= expanded_bytes - column;
return match bias {
Bias::Left => (collapsed_bytes, expanded_chars, expanded_bytes - column),
Bias::Right => (collapsed_bytes + 1, expanded_chars, 0),
};
}
} else {
expanded_chars += 1;
expanded_bytes += c.len_utf8();
}
if expanded_bytes > column && matches!(bias, Bias::Left) {
expanded_chars -= 1;
break;
}
collapsed_bytes += c.len_utf8();
}
(collapsed_bytes, expanded_chars, 0)
}
}
#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
pub struct TabPoint(pub Point);
impl TabPoint {
pub fn new(row: u32, column: u32) -> Self {
Self(Point::new(row, column))
}
pub fn zero() -> Self {
Self::new(0, 0)
}
pub fn row(self) -> u32 {
self.0.row
}
pub fn column(self) -> u32 {
self.0.column
}
}
impl From<Point> for TabPoint {
fn from(point: Point) -> Self {
Self(point)
}
}
pub type TabEdit = text::Edit<TabPoint>;
#[derive(Clone, Debug, Default, Eq, PartialEq)]
pub struct TextSummary {
pub lines: Point,
pub first_line_chars: u32,
pub last_line_chars: u32,
pub longest_row: u32,
pub longest_row_chars: u32,
}
impl<'a> From<&'a str> for TextSummary {
fn from(text: &'a str) -> Self {
let sum = text::TextSummary::from(text);
TextSummary {
lines: sum.lines,
first_line_chars: sum.first_line_chars,
last_line_chars: sum.last_line_chars,
longest_row: sum.longest_row,
longest_row_chars: sum.longest_row_chars,
}
}
}
impl<'a> std::ops::AddAssign<&'a Self> for TextSummary {
fn add_assign(&mut self, other: &'a Self) {
let joined_chars = self.last_line_chars + other.first_line_chars;
if joined_chars > self.longest_row_chars {
self.longest_row = self.lines.row;
self.longest_row_chars = joined_chars;
}
if other.longest_row_chars > self.longest_row_chars {
self.longest_row = self.lines.row + other.longest_row;
self.longest_row_chars = other.longest_row_chars;
}
if self.lines.row == 0 {
self.first_line_chars += other.first_line_chars;
}
if other.lines.row == 0 {
self.last_line_chars += other.first_line_chars;
} else {
self.last_line_chars = other.last_line_chars;
}
self.lines += &other.lines;
}
}
// Handles a tab width <= 16
const SPACES: &str = " ";
pub struct TabChunks<'a> {
fold_chunks: fold_map::FoldChunks<'a>,
chunk: Chunk<'a>,
column: usize,
output_position: Point,
max_output_position: Point,
tab_size: NonZeroU32,
skip_leading_tab: bool,
}
impl<'a> Iterator for TabChunks<'a> {
type Item = Chunk<'a>;
fn next(&mut self) -> Option<Self::Item> {
if self.chunk.text.is_empty() {
if let Some(chunk) = self.fold_chunks.next() {
self.chunk = chunk;
if self.skip_leading_tab {
self.chunk.text = &self.chunk.text[1..];
self.skip_leading_tab = false;
}
} else {
return None;
}
}
for (ix, c) in self.chunk.text.char_indices() {
match c {
'\t' => {
if ix > 0 {
let (prefix, suffix) = self.chunk.text.split_at(ix);
self.chunk.text = suffix;
return Some(Chunk {
text: prefix,
..self.chunk
});
} else {
self.chunk.text = &self.chunk.text[1..];
let tab_size = self.tab_size.get() as u32;
let mut len = tab_size - self.column as u32 % tab_size;
let next_output_position = cmp::min(
self.output_position + Point::new(0, len),
self.max_output_position,
);
len = next_output_position.column - self.output_position.column;
self.column += len as usize;
self.output_position = next_output_position;
return Some(Chunk {
text: &SPACES[0..len as usize],
..self.chunk
});
}
}
'\n' => {
self.column = 0;
self.output_position += Point::new(1, 0);
}
_ => {
self.column += 1;
self.output_position.column += c.len_utf8() as u32;
}
}
}
Some(mem::take(&mut self.chunk))
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::{display_map::fold_map::FoldMap, MultiBuffer};
use rand::{prelude::StdRng, Rng};
#[test]
fn test_expand_tabs() {
assert_eq!(
TabSnapshot::expand_tabs("\t".chars(), 0, 4.try_into().unwrap()),
0
);
assert_eq!(
TabSnapshot::expand_tabs("\t".chars(), 1, 4.try_into().unwrap()),
4
);
assert_eq!(
TabSnapshot::expand_tabs("\ta".chars(), 2, 4.try_into().unwrap()),
5
);
}
#[gpui::test(iterations = 100)]
fn test_random_tabs(cx: &mut gpui::MutableAppContext, mut rng: StdRng) {
let tab_size = NonZeroU32::new(rng.gen_range(1..=4)).unwrap();
let len = rng.gen_range(0..30);
let buffer = if rng.gen() {
let text = util::RandomCharIter::new(&mut rng)
.take(len)
.collect::<String>();
MultiBuffer::build_simple(&text, cx)
} else {
MultiBuffer::build_random(&mut rng, cx)
};
let buffer_snapshot = buffer.read(cx).snapshot(cx);
log::info!("Buffer text: {:?}", buffer_snapshot.text());
let (mut fold_map, _) = FoldMap::new(buffer_snapshot.clone());
fold_map.randomly_mutate(&mut rng);
let (folds_snapshot, _) = fold_map.read(buffer_snapshot, vec![]);
log::info!("FoldMap text: {:?}", folds_snapshot.text());
let (_, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), tab_size);
let text = text::Rope::from(tabs_snapshot.text().as_str());
log::info!(
"TabMap text (tab size: {}): {:?}",
tab_size,
tabs_snapshot.text(),
);
for _ in 0..5 {
let end_row = rng.gen_range(0..=text.max_point().row);
let end_column = rng.gen_range(0..=text.line_len(end_row));
let mut end = TabPoint(text.clip_point(Point::new(end_row, end_column), Bias::Right));
let start_row = rng.gen_range(0..=text.max_point().row);
let start_column = rng.gen_range(0..=text.line_len(start_row));
let mut start =
TabPoint(text.clip_point(Point::new(start_row, start_column), Bias::Left));
if start > end {
mem::swap(&mut start, &mut end);
}
let expected_text = text
.chunks_in_range(text.point_to_offset(start.0)..text.point_to_offset(end.0))
.collect::<String>();
let expected_summary = TextSummary::from(expected_text.as_str());
assert_eq!(
expected_text,
tabs_snapshot
.chunks(start..end, false, None)
.map(|c| c.text)
.collect::<String>(),
"chunks({:?}..{:?})",
start,
end
);
let mut actual_summary = tabs_snapshot.text_summary_for_range(start..end);
if tab_size.get() > 1 && folds_snapshot.text().contains('\t') {
actual_summary.longest_row = expected_summary.longest_row;
actual_summary.longest_row_chars = expected_summary.longest_row_chars;
}
assert_eq!(actual_summary, expected_summary);
}
for row in 0..=text.max_point().row {
assert_eq!(tabs_snapshot.line_len(row), text.line_len(row));
}
}
}