use super::{
fold_map::{self, FoldChunks, FoldEdit, FoldPoint, FoldSnapshot},
Highlights,
};
use crate::MultiBufferSnapshot;
use language::{Chunk, Point};
use std::{cmp, mem, num::NonZeroU32, ops::Range};
use sum_tree::Bias;
const MAX_EXPANSION_COLUMN: u32 = 256;
pub struct TabMap(TabSnapshot);
impl TabMap {
pub fn new(fold_snapshot: FoldSnapshot, tab_size: NonZeroU32) -> (Self, TabSnapshot) {
let snapshot = TabSnapshot {
fold_snapshot,
tab_size,
max_expansion_column: MAX_EXPANSION_COLUMN,
version: 0,
};
(Self(snapshot.clone()), snapshot)
}
#[cfg(test)]
pub fn set_max_expansion_column(&mut self, column: u32) -> TabSnapshot {
self.0.max_expansion_column = column;
self.0.clone()
}
pub fn sync(
&mut self,
fold_snapshot: FoldSnapshot,
mut fold_edits: Vec<FoldEdit>,
tab_size: NonZeroU32,
) -> (TabSnapshot, Vec<TabEdit>) {
let old_snapshot = &mut self.0;
let mut new_snapshot = TabSnapshot {
fold_snapshot,
tab_size,
max_expansion_column: old_snapshot.max_expansion_column,
version: old_snapshot.version,
};
if old_snapshot.fold_snapshot.version != new_snapshot.fold_snapshot.version {
new_snapshot.version += 1;
}
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 old_end = fold_edit.old.end.to_point(&old_snapshot.fold_snapshot);
let old_end_row_successor_offset = cmp::min(
FoldPoint::new(old_end.row() + 1, 0),
old_snapshot.fold_snapshot.max_point(),
)
.to_offset(&old_snapshot.fold_snapshot);
let new_end = fold_edit.new.end.to_point(&new_snapshot.fold_snapshot);
let mut offset_from_edit = 0;
let mut first_tab_offset = None;
let mut last_tab_with_changed_expansion_offset = None;
'outer: for chunk in old_snapshot.fold_snapshot.chunks(
fold_edit.old.end..old_end_row_successor_offset,
false,
Highlights::default(),
) {
for (ix, _) in chunk.text.match_indices('\t') {
let offset_from_edit = offset_from_edit + (ix as u32);
if first_tab_offset.is_none() {
first_tab_offset = Some(offset_from_edit);
}
let old_column = old_end.column() + offset_from_edit;
let new_column = new_end.column() + offset_from_edit;
let was_expanded = old_column < old_snapshot.max_expansion_column;
let is_expanded = new_column < new_snapshot.max_expansion_column;
if was_expanded != is_expanded {
last_tab_with_changed_expansion_offset = Some(offset_from_edit);
} else if !was_expanded && !is_expanded {
break 'outer;
}
}
offset_from_edit += chunk.text.len() as u32;
if old_end.column() + offset_from_edit >= old_snapshot.max_expansion_column
&& new_end.column() + offset_from_edit >= new_snapshot.max_expansion_column
{
break;
}
}
if let Some(offset) = last_tab_with_changed_expansion_offset.or(first_tab_offset) {
fold_edit.old.end.0 += offset as usize + 1;
fold_edit.new.end.0 += offset as usize + 1;
}
}
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 max_expansion_column: u32,
pub version: usize,
}
impl TabSnapshot {
pub fn buffer_snapshot(&self) -> &MultiBufferSnapshot {
&self.fold_snapshot.inlay_snapshot.buffer
}
pub fn line_len(&self, row: u32) -> u32 {
let max_point = self.max_point();
if row < max_point.row() {
self.to_tab_point(FoldPoint::new(row, self.fold_snapshot.line_len(row)))
.0
.column
} 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, Highlights::default())
.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,
Highlights::default(),
)
.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,
highlights: Highlights<'a>,
) -> TabChunks<'a> {
let (input_start, expanded_char_column, to_next_stop) =
self.to_fold_point(range.start, Bias::Left);
let input_column = input_start.column();
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) > range.end.0 {
range.end.column() - range.start.column()
} else {
to_next_stop
};
TabChunks {
fold_chunks: self.fold_snapshot.chunks(
input_start..input_end,
language_aware,
highlights,
),
input_column,
column: expanded_char_column,
max_expansion_column: self.max_expansion_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 as usize)],
is_tab: true,
..Default::default()
},
inside_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,
Highlights::default(),
)
.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());
TabPoint::new(input.row(), expanded)
}
pub fn to_fold_point(&self, output: TabPoint, bias: Bias) -> (FoldPoint, u32, u32) {
let chars = self.fold_snapshot.chars_at(FoldPoint::new(output.row(), 0));
let expanded = output.column();
let (collapsed, expanded_char_column, to_next_stop) =
self.collapse_tabs(chars, expanded, bias);
(
FoldPoint::new(output.row(), collapsed as u32),
expanded_char_column,
to_next_stop,
)
}
pub fn make_tab_point(&self, point: Point, bias: Bias) -> TabPoint {
let inlay_point = self.fold_snapshot.inlay_snapshot.to_inlay_point(point);
let fold_point = self.fold_snapshot.to_fold_point(inlay_point, bias);
self.to_tab_point(fold_point)
}
pub fn to_point(&self, point: TabPoint, bias: Bias) -> Point {
let fold_point = self.to_fold_point(point, bias).0;
let inlay_point = fold_point.to_inlay_point(&self.fold_snapshot);
self.fold_snapshot
.inlay_snapshot
.to_buffer_point(inlay_point)
}
fn expand_tabs(&self, chars: impl Iterator<Item = char>, column: u32) -> u32 {
let tab_size = self.tab_size.get();
let mut expanded_chars = 0;
let mut expanded_bytes = 0;
let mut collapsed_bytes = 0;
let end_column = column.min(self.max_expansion_column);
for c in chars {
if collapsed_bytes >= end_column {
break;
}
if c == '\t' {
let tab_len = tab_size - expanded_chars % tab_size;
expanded_bytes += tab_len;
expanded_chars += tab_len;
} else {
expanded_bytes += c.len_utf8() as u32;
expanded_chars += 1;
}
collapsed_bytes += c.len_utf8() as u32;
}
expanded_bytes + column.saturating_sub(collapsed_bytes)
}
fn collapse_tabs(
&self,
chars: impl Iterator<Item = char>,
column: u32,
bias: Bias,
) -> (u32, u32, u32) {
let tab_size = self.tab_size.get();
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 collapsed_bytes >= self.max_expansion_column {
break;
}
if c == '\t' {
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() as u32;
}
if expanded_bytes > column && matches!(bias, Bias::Left) {
expanded_chars -= 1;
break;
}
collapsed_bytes += c.len_utf8() as u32;
}
(
collapsed_bytes + column.saturating_sub(expanded_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;
}
}
const SPACES: &str = " ";
pub struct TabChunks<'a> {
fold_chunks: FoldChunks<'a>,
chunk: Chunk<'a>,
column: u32,
max_expansion_column: u32,
output_position: Point,
input_column: u32,
max_output_position: Point,
tab_size: NonZeroU32,
inside_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.inside_leading_tab {
self.chunk.text = &self.chunk.text[1..];
self.inside_leading_tab = false;
self.input_column += 1;
}
} 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 = if self.input_column < self.max_expansion_column {
self.tab_size.get() as u32
} else {
1
};
let mut len = tab_size - self.column % 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;
self.input_column += 1;
self.output_position = next_output_position;
return Some(Chunk {
text: &SPACES[..len as usize],
is_tab: true,
..self.chunk
});
}
}
'\n' => {
self.column = 0;
self.input_column = 0;
self.output_position += Point::new(1, 0);
}
_ => {
self.column += 1;
if !self.inside_leading_tab {
self.input_column += c.len_utf8() as u32;
}
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, inlay_map::InlayMap},
MultiBuffer,
};
use rand::{prelude::StdRng, Rng};
#[gpui::test]
fn test_expand_tabs(cx: &mut gpui::AppContext) {
let buffer = MultiBuffer::build_simple("", cx);
let buffer_snapshot = buffer.read(cx).snapshot(cx);
let (_, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
let (_, fold_snapshot) = FoldMap::new(inlay_snapshot);
let (_, tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
assert_eq!(tab_snapshot.expand_tabs("\t".chars(), 0), 0);
assert_eq!(tab_snapshot.expand_tabs("\t".chars(), 1), 4);
assert_eq!(tab_snapshot.expand_tabs("\ta".chars(), 2), 5);
}
#[gpui::test]
fn test_long_lines(cx: &mut gpui::AppContext) {
let max_expansion_column = 12;
let input = "A\tBC\tDEF\tG\tHI\tJ\tK\tL\tM";
let output = "A BC DEF G HI J K L M";
let buffer = MultiBuffer::build_simple(input, cx);
let buffer_snapshot = buffer.read(cx).snapshot(cx);
let (_, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
let (_, fold_snapshot) = FoldMap::new(inlay_snapshot);
let (_, mut tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
tab_snapshot.max_expansion_column = max_expansion_column;
assert_eq!(tab_snapshot.text(), output);
for (ix, c) in input.char_indices() {
assert_eq!(
tab_snapshot
.chunks(
TabPoint::new(0, ix as u32)..tab_snapshot.max_point(),
false,
Highlights::default(),
)
.map(|c| c.text)
.collect::<String>(),
&output[ix..],
"text from index {ix}"
);
if c != '\t' {
let input_point = Point::new(0, ix as u32);
let output_point = Point::new(0, output.find(c).unwrap() as u32);
assert_eq!(
tab_snapshot.to_tab_point(FoldPoint(input_point)),
TabPoint(output_point),
"to_tab_point({input_point:?})"
);
assert_eq!(
tab_snapshot
.to_fold_point(TabPoint(output_point), Bias::Left)
.0,
FoldPoint(input_point),
"to_fold_point({output_point:?})"
);
}
}
}
#[gpui::test]
fn test_long_lines_with_character_spanning_max_expansion_column(cx: &mut gpui::AppContext) {
let max_expansion_column = 8;
let input = "abcdefg⋯hij";
let buffer = MultiBuffer::build_simple(input, cx);
let buffer_snapshot = buffer.read(cx).snapshot(cx);
let (_, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
let (_, fold_snapshot) = FoldMap::new(inlay_snapshot);
let (_, mut tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
tab_snapshot.max_expansion_column = max_expansion_column;
assert_eq!(tab_snapshot.text(), input);
}
#[gpui::test]
fn test_marking_tabs(cx: &mut gpui::AppContext) {
let input = "\t \thello";
let buffer = MultiBuffer::build_simple(&input, cx);
let buffer_snapshot = buffer.read(cx).snapshot(cx);
let (_, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
let (_, fold_snapshot) = FoldMap::new(inlay_snapshot);
let (_, tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
assert_eq!(
chunks(&tab_snapshot, TabPoint::zero()),
vec![
(" ".to_string(), true),
(" ".to_string(), false),
(" ".to_string(), true),
("hello".to_string(), false),
]
);
assert_eq!(
chunks(&tab_snapshot, TabPoint::new(0, 2)),
vec![
(" ".to_string(), true),
(" ".to_string(), false),
(" ".to_string(), true),
("hello".to_string(), false),
]
);
fn chunks(snapshot: &TabSnapshot, start: TabPoint) -> Vec<(String, bool)> {
let mut chunks = Vec::new();
let mut was_tab = false;
let mut text = String::new();
for chunk in snapshot.chunks(start..snapshot.max_point(), false, Highlights::default())
{
if chunk.is_tab != was_tab {
if !text.is_empty() {
chunks.push((mem::take(&mut text), was_tab));
}
was_tab = chunk.is_tab;
}
text.push_str(chunk.text);
}
if !text.is_empty() {
chunks.push((text, was_tab));
}
chunks
}
}
#[gpui::test(iterations = 100)]
fn test_random_tabs(cx: &mut gpui::AppContext, 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 inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
log::info!("InlayMap text: {:?}", inlay_snapshot.text());
let (mut fold_map, _) = FoldMap::new(inlay_snapshot.clone());
fold_map.randomly_mutate(&mut rng);
let (fold_snapshot, _) = fold_map.read(inlay_snapshot, vec![]);
log::info!("FoldMap text: {:?}", fold_snapshot.text());
let (inlay_snapshot, _) = inlay_map.randomly_mutate(&mut 0, &mut rng);
log::info!("InlayMap text: {:?}", inlay_snapshot.text());
let (mut tab_map, _) = TabMap::new(fold_snapshot.clone(), tab_size);
let tabs_snapshot = tab_map.set_max_expansion_column(32);
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!(
tabs_snapshot
.chunks(start..end, false, Highlights::default())
.map(|c| c.text)
.collect::<String>(),
expected_text,
"chunks({:?}..{:?})",
start,
end
);
let mut actual_summary = tabs_snapshot.text_summary_for_range(start..end);
if tab_size.get() > 1 && inlay_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),
"line_len({row})"
);
}
}
}