ZIm/crates/editor/src/display_map/tab_map.rs
Max Brunsfeld c539069cbb Include diagnostic info in HighlightedChunks iterator
Co-Authored-By: Nathan Sobo <nathan@zed.dev>
2021-10-26 17:57:50 -07:00

481 lines
15 KiB
Rust

use super::fold_map::{self, FoldEdit, FoldPoint, Snapshot as FoldSnapshot};
use language::{rope, HighlightedChunk};
use parking_lot::Mutex;
use std::{mem, ops::Range};
use sum_tree::Bias;
pub struct TabMap(Mutex<Snapshot>);
impl TabMap {
pub fn new(input: FoldSnapshot, tab_size: usize) -> (Self, Snapshot) {
let snapshot = Snapshot {
fold_snapshot: input,
tab_size,
};
(Self(Mutex::new(snapshot.clone())), snapshot)
}
pub fn sync(
&self,
fold_snapshot: FoldSnapshot,
mut fold_edits: Vec<FoldEdit>,
) -> (Snapshot, Vec<Edit>) {
let mut old_snapshot = self.0.lock();
let new_snapshot = Snapshot {
fold_snapshot,
tab_size: old_snapshot.tab_size,
};
let mut tab_edits = Vec::with_capacity(fold_edits.len());
for fold_edit in &mut fold_edits {
let mut delta = 0;
for chunk in old_snapshot
.fold_snapshot
.chunks_at(fold_edit.old_bytes.end)
{
let patterns: &[_] = &['\t', '\n'];
if let Some(ix) = chunk.find(patterns) {
if &chunk[ix..ix + 1] == "\t" {
fold_edit.old_bytes.end.0 += delta + ix + 1;
fold_edit.new_bytes.end.0 += delta + ix + 1;
}
break;
}
delta += chunk.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_bytes.end >= edit.old_bytes.start {
prev_edit.old_bytes.end = edit.old_bytes.end;
prev_edit.new_bytes.end = edit.new_bytes.end;
fold_edits.remove(ix);
} else {
ix += 1;
}
}
for fold_edit in fold_edits {
let old_start = fold_edit
.old_bytes
.start
.to_point(&old_snapshot.fold_snapshot);
let old_end = fold_edit
.old_bytes
.end
.to_point(&old_snapshot.fold_snapshot);
let new_start = fold_edit
.new_bytes
.start
.to_point(&new_snapshot.fold_snapshot);
let new_end = fold_edit
.new_bytes
.end
.to_point(&new_snapshot.fold_snapshot);
tab_edits.push(Edit {
old_lines: old_snapshot.to_tab_point(old_start)..old_snapshot.to_tab_point(old_end),
new_lines: new_snapshot.to_tab_point(new_start)..new_snapshot.to_tab_point(new_end),
});
}
*old_snapshot = new_snapshot;
(old_snapshot.clone(), tab_edits)
}
}
#[derive(Clone)]
pub struct Snapshot {
pub fold_snapshot: FoldSnapshot,
pub tab_size: usize,
}
impl Snapshot {
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 mut first_line_bytes = 0;
for c in self.chunks_at(range.start).flat_map(|chunk| chunk.chars()) {
if c == '\n'
|| (range.start.row() == range.end.row() && first_line_bytes == range.end.column())
{
break;
}
first_line_chars += 1;
first_line_bytes += c.len_utf8() as u32;
}
let mut last_line_chars = 0;
let mut last_line_bytes = 0;
for c in self
.chunks_at(TabPoint::new(range.end.row(), 0).max(range.start))
.flat_map(|chunk| chunk.chars())
{
if last_line_bytes == range.end.column() {
break;
}
last_line_chars += 1;
last_line_bytes += c.len_utf8() as u32;
}
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 version(&self) -> usize {
self.fold_snapshot.version
}
pub fn chunks_at(&self, point: TabPoint) -> Chunks {
let (point, expanded_char_column, to_next_stop) = self.to_fold_point(point, Bias::Left);
let fold_chunks = self
.fold_snapshot
.chunks_at(point.to_offset(&self.fold_snapshot));
Chunks {
fold_chunks,
column: expanded_char_column,
tab_size: self.tab_size,
chunk: &SPACES[0..to_next_stop],
skip_leading_tab: to_next_stop > 0,
}
}
pub fn highlighted_chunks(&mut self, range: Range<TabPoint>) -> HighlightedChunks {
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);
HighlightedChunks {
fold_chunks: self
.fold_snapshot
.highlighted_chunks(input_start..input_end),
column: expanded_char_column,
tab_size: self.tab_size,
chunk: HighlightedChunk {
text: &SPACES[0..to_next_stop],
..Default::default()
},
skip_leading_tab: to_next_stop > 0,
}
}
pub fn buffer_rows(&self, row: u32) -> fold_map::BufferRows {
self.fold_snapshot.buffer_rows(row)
}
#[cfg(test)]
pub fn text(&self) -> String {
self.chunks_at(Default::default()).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,
)
}
fn expand_tabs(chars: impl Iterator<Item = char>, column: usize, tab_size: usize) -> 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_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(
mut chars: impl Iterator<Item = char>,
column: usize,
bias: Bias,
tab_size: usize,
) -> (usize, usize, usize) {
let mut expanded_bytes = 0;
let mut expanded_chars = 0;
let mut collapsed_bytes = 0;
while let Some(c) = chars.next() {
if expanded_bytes >= 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();
}
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 super::Point);
impl TabPoint {
pub fn new(row: u32, column: u32) -> Self {
Self(super::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<super::Point> for TabPoint {
fn from(point: super::Point) -> Self {
Self(point)
}
}
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct Edit {
pub old_lines: Range<TabPoint>,
pub new_lines: Range<TabPoint>,
}
#[derive(Clone, Debug, Default, Eq, PartialEq)]
pub struct TextSummary {
pub lines: super::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 = rope::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: &'static str = " ";
pub struct Chunks<'a> {
fold_chunks: fold_map::Chunks<'a>,
chunk: &'a str,
column: usize,
tab_size: usize,
skip_leading_tab: bool,
}
impl<'a> Iterator for Chunks<'a> {
type Item = &'a str;
fn next(&mut self) -> Option<Self::Item> {
if self.chunk.is_empty() {
if let Some(chunk) = self.fold_chunks.next() {
self.chunk = chunk;
if self.skip_leading_tab {
self.chunk = &self.chunk[1..];
self.skip_leading_tab = false;
}
} else {
return None;
}
}
for (ix, c) in self.chunk.char_indices() {
match c {
'\t' => {
if ix > 0 {
let (prefix, suffix) = self.chunk.split_at(ix);
self.chunk = suffix;
return Some(prefix);
} else {
self.chunk = &self.chunk[1..];
let len = self.tab_size - self.column % self.tab_size;
self.column += len;
return Some(&SPACES[0..len]);
}
}
'\n' => self.column = 0,
_ => self.column += 1,
}
}
let result = Some(self.chunk);
self.chunk = "";
result
}
}
pub struct HighlightedChunks<'a> {
fold_chunks: fold_map::HighlightedChunks<'a>,
chunk: HighlightedChunk<'a>,
column: usize,
tab_size: usize,
skip_leading_tab: bool,
}
impl<'a> Iterator for HighlightedChunks<'a> {
type Item = HighlightedChunk<'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(HighlightedChunk {
text: prefix,
..self.chunk
});
} else {
self.chunk.text = &self.chunk.text[1..];
let len = self.tab_size - self.column % self.tab_size;
self.column += len;
return Some(HighlightedChunk {
text: &SPACES[0..len],
..self.chunk
});
}
}
'\n' => self.column = 0,
_ => self.column += 1,
}
}
Some(mem::take(&mut self.chunk))
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_expand_tabs() {
assert_eq!(Snapshot::expand_tabs("\t".chars(), 0, 4), 0);
assert_eq!(Snapshot::expand_tabs("\t".chars(), 1, 4), 4);
assert_eq!(Snapshot::expand_tabs("\ta".chars(), 2, 4), 5);
}
}