wrap_map.rs

   1use super::{
   2    fold_map::FoldBufferRows,
   3    tab_map::{self, TabEdit, TabPoint, TabSnapshot},
   4    Highlights,
   5};
   6use crate::MultiBufferSnapshot;
   7use gpui::{AppContext, Context, Font, LineWrapper, Model, ModelContext, Pixels, Task};
   8use language::{Chunk, Point};
   9use lazy_static::lazy_static;
  10use smol::future::yield_now;
  11use std::{cmp, collections::VecDeque, mem, ops::Range, time::Duration};
  12use sum_tree::{Bias, Cursor, SumTree};
  13use text::Patch;
  14use util::ResultExt;
  15
  16pub use super::tab_map::TextSummary;
  17pub type WrapEdit = text::Edit<u32>;
  18
  19pub struct WrapMap {
  20    snapshot: WrapSnapshot,
  21    pending_edits: VecDeque<(TabSnapshot, Vec<TabEdit>)>,
  22    interpolated_edits: Patch<u32>,
  23    edits_since_sync: Patch<u32>,
  24    wrap_width: Option<Pixels>,
  25    background_task: Option<Task<()>>,
  26    font_with_size: (Font, Pixels),
  27}
  28
  29#[derive(Clone)]
  30pub struct WrapSnapshot {
  31    tab_snapshot: TabSnapshot,
  32    transforms: SumTree<Transform>,
  33    interpolated: bool,
  34}
  35
  36#[derive(Clone, Debug, Default, Eq, PartialEq)]
  37struct Transform {
  38    summary: TransformSummary,
  39    display_text: Option<&'static str>,
  40}
  41
  42#[derive(Clone, Debug, Default, Eq, PartialEq)]
  43struct TransformSummary {
  44    input: TextSummary,
  45    output: TextSummary,
  46}
  47
  48#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  49pub struct WrapPoint(pub Point);
  50
  51pub struct WrapChunks<'a> {
  52    input_chunks: tab_map::TabChunks<'a>,
  53    input_chunk: Chunk<'a>,
  54    output_position: WrapPoint,
  55    max_output_row: u32,
  56    transforms: Cursor<'a, Transform, (WrapPoint, TabPoint)>,
  57}
  58
  59#[derive(Clone)]
  60pub struct WrapBufferRows<'a> {
  61    input_buffer_rows: FoldBufferRows<'a>,
  62    input_buffer_row: Option<u32>,
  63    output_row: u32,
  64    soft_wrapped: bool,
  65    max_output_row: u32,
  66    transforms: Cursor<'a, Transform, (WrapPoint, TabPoint)>,
  67}
  68
  69impl WrapMap {
  70    pub fn new(
  71        tab_snapshot: TabSnapshot,
  72        font: Font,
  73        font_size: Pixels,
  74        wrap_width: Option<Pixels>,
  75        cx: &mut AppContext,
  76    ) -> (Model<Self>, WrapSnapshot) {
  77        let handle = cx.build_model(|cx| {
  78            let mut this = Self {
  79                font_with_size: (font, font_size),
  80                wrap_width: None,
  81                pending_edits: Default::default(),
  82                interpolated_edits: Default::default(),
  83                edits_since_sync: Default::default(),
  84                snapshot: WrapSnapshot::new(tab_snapshot),
  85                background_task: None,
  86            };
  87            this.set_wrap_width(wrap_width, cx);
  88            mem::take(&mut this.edits_since_sync);
  89            this
  90        });
  91        let snapshot = handle.read(cx).snapshot.clone();
  92        (handle, snapshot)
  93    }
  94
  95    #[cfg(test)]
  96    pub fn is_rewrapping(&self) -> bool {
  97        self.background_task.is_some()
  98    }
  99
 100    pub fn sync(
 101        &mut self,
 102        tab_snapshot: TabSnapshot,
 103        edits: Vec<TabEdit>,
 104        cx: &mut ModelContext<Self>,
 105    ) -> (WrapSnapshot, Patch<u32>) {
 106        if self.wrap_width.is_some() {
 107            self.pending_edits.push_back((tab_snapshot, edits));
 108            self.flush_edits(cx);
 109        } else {
 110            self.edits_since_sync = self
 111                .edits_since_sync
 112                .compose(&self.snapshot.interpolate(tab_snapshot, &edits));
 113            self.snapshot.interpolated = false;
 114        }
 115
 116        (self.snapshot.clone(), mem::take(&mut self.edits_since_sync))
 117    }
 118
 119    pub fn set_font_with_size(
 120        &mut self,
 121        font: Font,
 122        font_size: Pixels,
 123        cx: &mut ModelContext<Self>,
 124    ) -> bool {
 125        let font_with_size = (font, font_size);
 126
 127        if font_with_size != self.font_with_size {
 128            self.font_with_size = font_with_size;
 129            self.rewrap(cx);
 130            true
 131        } else {
 132            false
 133        }
 134    }
 135
 136    pub fn set_wrap_width(
 137        &mut self,
 138        wrap_width: Option<Pixels>,
 139        cx: &mut ModelContext<Self>,
 140    ) -> bool {
 141        if wrap_width == self.wrap_width {
 142            return false;
 143        }
 144
 145        self.wrap_width = wrap_width;
 146        self.rewrap(cx);
 147        true
 148    }
 149
 150    fn rewrap(&mut self, cx: &mut ModelContext<Self>) {
 151        self.background_task.take();
 152        self.interpolated_edits.clear();
 153        self.pending_edits.clear();
 154
 155        if let Some(wrap_width) = self.wrap_width {
 156            let mut new_snapshot = self.snapshot.clone();
 157            let mut edits = Patch::default();
 158            let text_system = cx.text_system().clone();
 159            let (font, font_size) = self.font_with_size.clone();
 160            let task = cx.background_executor().spawn(async move {
 161                if let Some(mut line_wrapper) = text_system.line_wrapper(font, font_size).log_err()
 162                {
 163                    let tab_snapshot = new_snapshot.tab_snapshot.clone();
 164                    let range = TabPoint::zero()..tab_snapshot.max_point();
 165                    edits = new_snapshot
 166                        .update(
 167                            tab_snapshot,
 168                            &[TabEdit {
 169                                old: range.clone(),
 170                                new: range.clone(),
 171                            }],
 172                            wrap_width,
 173                            &mut line_wrapper,
 174                        )
 175                        .await;
 176                }
 177                (new_snapshot, edits)
 178            });
 179
 180            match cx
 181                .background_executor()
 182                .block_with_timeout(Duration::from_millis(5), task)
 183            {
 184                Ok((snapshot, edits)) => {
 185                    self.snapshot = snapshot;
 186                    self.edits_since_sync = self.edits_since_sync.compose(&edits);
 187                    cx.notify();
 188                }
 189                Err(wrap_task) => {
 190                    self.background_task = Some(cx.spawn(|this, mut cx| async move {
 191                        let (snapshot, edits) = wrap_task.await;
 192                        this.update(&mut cx, |this, cx| {
 193                            this.snapshot = snapshot;
 194                            this.edits_since_sync = this
 195                                .edits_since_sync
 196                                .compose(mem::take(&mut this.interpolated_edits).invert())
 197                                .compose(&edits);
 198                            this.background_task = None;
 199                            this.flush_edits(cx);
 200                            cx.notify();
 201                        });
 202                    }));
 203                }
 204            }
 205        } else {
 206            let old_rows = self.snapshot.transforms.summary().output.lines.row + 1;
 207            self.snapshot.transforms = SumTree::new();
 208            let summary = self.snapshot.tab_snapshot.text_summary();
 209            if !summary.lines.is_zero() {
 210                self.snapshot
 211                    .transforms
 212                    .push(Transform::isomorphic(summary), &());
 213            }
 214            let new_rows = self.snapshot.transforms.summary().output.lines.row + 1;
 215            self.snapshot.interpolated = false;
 216            self.edits_since_sync = self.edits_since_sync.compose(&Patch::new(vec![WrapEdit {
 217                old: 0..old_rows,
 218                new: 0..new_rows,
 219            }]));
 220        }
 221    }
 222
 223    fn flush_edits(&mut self, cx: &mut ModelContext<Self>) {
 224        if !self.snapshot.interpolated {
 225            let mut to_remove_len = 0;
 226            for (tab_snapshot, _) in &self.pending_edits {
 227                if tab_snapshot.version <= self.snapshot.tab_snapshot.version {
 228                    to_remove_len += 1;
 229                } else {
 230                    break;
 231                }
 232            }
 233            self.pending_edits.drain(..to_remove_len);
 234        }
 235
 236        if self.pending_edits.is_empty() {
 237            return;
 238        }
 239
 240        if let Some(wrap_width) = self.wrap_width {
 241            if self.background_task.is_none() {
 242                let pending_edits = self.pending_edits.clone();
 243                let mut snapshot = self.snapshot.clone();
 244                let text_system = cx.text_system().clone();
 245                let (font, font_size) = self.font_with_size.clone();
 246                let update_task = cx.background_executor().spawn(async move {
 247                    let mut edits = Patch::default();
 248                    if let Some(mut line_wrapper) =
 249                        text_system.line_wrapper(font, font_size).log_err()
 250                    {
 251                        for (tab_snapshot, tab_edits) in pending_edits {
 252                            let wrap_edits = snapshot
 253                                .update(tab_snapshot, &tab_edits, wrap_width, &mut line_wrapper)
 254                                .await;
 255                            edits = edits.compose(&wrap_edits);
 256                        }
 257                    }
 258                    (snapshot, edits)
 259                });
 260
 261                match cx
 262                    .background_executor()
 263                    .block_with_timeout(Duration::from_millis(1), update_task)
 264                {
 265                    Ok((snapshot, output_edits)) => {
 266                        self.snapshot = snapshot;
 267                        self.edits_since_sync = self.edits_since_sync.compose(&output_edits);
 268                    }
 269                    Err(update_task) => {
 270                        self.background_task = Some(cx.spawn(|this, mut cx| async move {
 271                            let (snapshot, edits) = update_task.await;
 272                            this.update(&mut cx, |this, cx| {
 273                                this.snapshot = snapshot;
 274                                this.edits_since_sync = this
 275                                    .edits_since_sync
 276                                    .compose(mem::take(&mut this.interpolated_edits).invert())
 277                                    .compose(&edits);
 278                                this.background_task = None;
 279                                this.flush_edits(cx);
 280                                cx.notify();
 281                            });
 282                        }));
 283                    }
 284                }
 285            }
 286        }
 287
 288        let was_interpolated = self.snapshot.interpolated;
 289        let mut to_remove_len = 0;
 290        for (tab_snapshot, edits) in &self.pending_edits {
 291            if tab_snapshot.version <= self.snapshot.tab_snapshot.version {
 292                to_remove_len += 1;
 293            } else {
 294                let interpolated_edits = self.snapshot.interpolate(tab_snapshot.clone(), edits);
 295                self.edits_since_sync = self.edits_since_sync.compose(&interpolated_edits);
 296                self.interpolated_edits = self.interpolated_edits.compose(&interpolated_edits);
 297            }
 298        }
 299
 300        if !was_interpolated {
 301            self.pending_edits.drain(..to_remove_len);
 302        }
 303    }
 304}
 305
 306impl WrapSnapshot {
 307    fn new(tab_snapshot: TabSnapshot) -> Self {
 308        let mut transforms = SumTree::new();
 309        let extent = tab_snapshot.text_summary();
 310        if !extent.lines.is_zero() {
 311            transforms.push(Transform::isomorphic(extent), &());
 312        }
 313        Self {
 314            transforms,
 315            tab_snapshot,
 316            interpolated: true,
 317        }
 318    }
 319
 320    pub fn buffer_snapshot(&self) -> &MultiBufferSnapshot {
 321        self.tab_snapshot.buffer_snapshot()
 322    }
 323
 324    fn interpolate(&mut self, new_tab_snapshot: TabSnapshot, tab_edits: &[TabEdit]) -> Patch<u32> {
 325        let mut new_transforms;
 326        if tab_edits.is_empty() {
 327            new_transforms = self.transforms.clone();
 328        } else {
 329            let mut old_cursor = self.transforms.cursor::<TabPoint>();
 330
 331            let mut tab_edits_iter = tab_edits.iter().peekable();
 332            new_transforms =
 333                old_cursor.slice(&tab_edits_iter.peek().unwrap().old.start, Bias::Right, &());
 334
 335            while let Some(edit) = tab_edits_iter.next() {
 336                if edit.new.start > TabPoint::from(new_transforms.summary().input.lines) {
 337                    let summary = new_tab_snapshot.text_summary_for_range(
 338                        TabPoint::from(new_transforms.summary().input.lines)..edit.new.start,
 339                    );
 340                    new_transforms.push_or_extend(Transform::isomorphic(summary));
 341                }
 342
 343                if !edit.new.is_empty() {
 344                    new_transforms.push_or_extend(Transform::isomorphic(
 345                        new_tab_snapshot.text_summary_for_range(edit.new.clone()),
 346                    ));
 347                }
 348
 349                old_cursor.seek_forward(&edit.old.end, Bias::Right, &());
 350                if let Some(next_edit) = tab_edits_iter.peek() {
 351                    if next_edit.old.start > old_cursor.end(&()) {
 352                        if old_cursor.end(&()) > edit.old.end {
 353                            let summary = self
 354                                .tab_snapshot
 355                                .text_summary_for_range(edit.old.end..old_cursor.end(&()));
 356                            new_transforms.push_or_extend(Transform::isomorphic(summary));
 357                        }
 358
 359                        old_cursor.next(&());
 360                        new_transforms.append(
 361                            old_cursor.slice(&next_edit.old.start, Bias::Right, &()),
 362                            &(),
 363                        );
 364                    }
 365                } else {
 366                    if old_cursor.end(&()) > edit.old.end {
 367                        let summary = self
 368                            .tab_snapshot
 369                            .text_summary_for_range(edit.old.end..old_cursor.end(&()));
 370                        new_transforms.push_or_extend(Transform::isomorphic(summary));
 371                    }
 372                    old_cursor.next(&());
 373                    new_transforms.append(old_cursor.suffix(&()), &());
 374                }
 375            }
 376        }
 377
 378        let old_snapshot = mem::replace(
 379            self,
 380            WrapSnapshot {
 381                tab_snapshot: new_tab_snapshot,
 382                transforms: new_transforms,
 383                interpolated: true,
 384            },
 385        );
 386        self.check_invariants();
 387        old_snapshot.compute_edits(tab_edits, self)
 388    }
 389
 390    async fn update(
 391        &mut self,
 392        new_tab_snapshot: TabSnapshot,
 393        tab_edits: &[TabEdit],
 394        wrap_width: Pixels,
 395        line_wrapper: &mut LineWrapper,
 396    ) -> Patch<u32> {
 397        #[derive(Debug)]
 398        struct RowEdit {
 399            old_rows: Range<u32>,
 400            new_rows: Range<u32>,
 401        }
 402
 403        let mut tab_edits_iter = tab_edits.iter().peekable();
 404        let mut row_edits = Vec::new();
 405        while let Some(edit) = tab_edits_iter.next() {
 406            let mut row_edit = RowEdit {
 407                old_rows: edit.old.start.row()..edit.old.end.row() + 1,
 408                new_rows: edit.new.start.row()..edit.new.end.row() + 1,
 409            };
 410
 411            while let Some(next_edit) = tab_edits_iter.peek() {
 412                if next_edit.old.start.row() <= row_edit.old_rows.end {
 413                    row_edit.old_rows.end = next_edit.old.end.row() + 1;
 414                    row_edit.new_rows.end = next_edit.new.end.row() + 1;
 415                    tab_edits_iter.next();
 416                } else {
 417                    break;
 418                }
 419            }
 420
 421            row_edits.push(row_edit);
 422        }
 423
 424        let mut new_transforms;
 425        if row_edits.is_empty() {
 426            new_transforms = self.transforms.clone();
 427        } else {
 428            let mut row_edits = row_edits.into_iter().peekable();
 429            let mut old_cursor = self.transforms.cursor::<TabPoint>();
 430
 431            new_transforms = old_cursor.slice(
 432                &TabPoint::new(row_edits.peek().unwrap().old_rows.start, 0),
 433                Bias::Right,
 434                &(),
 435            );
 436
 437            while let Some(edit) = row_edits.next() {
 438                if edit.new_rows.start > new_transforms.summary().input.lines.row {
 439                    let summary = new_tab_snapshot.text_summary_for_range(
 440                        TabPoint(new_transforms.summary().input.lines)
 441                            ..TabPoint::new(edit.new_rows.start, 0),
 442                    );
 443                    new_transforms.push_or_extend(Transform::isomorphic(summary));
 444                }
 445
 446                let mut line = String::new();
 447                let mut remaining = None;
 448                let mut chunks = new_tab_snapshot.chunks(
 449                    TabPoint::new(edit.new_rows.start, 0)..new_tab_snapshot.max_point(),
 450                    false,
 451                    Highlights::default(),
 452                );
 453                let mut edit_transforms = Vec::<Transform>::new();
 454                for _ in edit.new_rows.start..edit.new_rows.end {
 455                    while let Some(chunk) =
 456                        remaining.take().or_else(|| chunks.next().map(|c| c.text))
 457                    {
 458                        if let Some(ix) = chunk.find('\n') {
 459                            line.push_str(&chunk[..ix + 1]);
 460                            remaining = Some(&chunk[ix + 1..]);
 461                            break;
 462                        } else {
 463                            line.push_str(chunk)
 464                        }
 465                    }
 466
 467                    if line.is_empty() {
 468                        break;
 469                    }
 470
 471                    let mut prev_boundary_ix = 0;
 472                    for boundary in line_wrapper.wrap_line(&line, wrap_width) {
 473                        let wrapped = &line[prev_boundary_ix..boundary.ix];
 474                        push_isomorphic(&mut edit_transforms, TextSummary::from(wrapped));
 475                        edit_transforms.push(Transform::wrap(boundary.next_indent));
 476                        prev_boundary_ix = boundary.ix;
 477                    }
 478
 479                    if prev_boundary_ix < line.len() {
 480                        push_isomorphic(
 481                            &mut edit_transforms,
 482                            TextSummary::from(&line[prev_boundary_ix..]),
 483                        );
 484                    }
 485
 486                    line.clear();
 487                    yield_now().await;
 488                }
 489
 490                let mut edit_transforms = edit_transforms.into_iter();
 491                if let Some(transform) = edit_transforms.next() {
 492                    new_transforms.push_or_extend(transform);
 493                }
 494                new_transforms.extend(edit_transforms, &());
 495
 496                old_cursor.seek_forward(&TabPoint::new(edit.old_rows.end, 0), Bias::Right, &());
 497                if let Some(next_edit) = row_edits.peek() {
 498                    if next_edit.old_rows.start > old_cursor.end(&()).row() {
 499                        if old_cursor.end(&()) > TabPoint::new(edit.old_rows.end, 0) {
 500                            let summary = self.tab_snapshot.text_summary_for_range(
 501                                TabPoint::new(edit.old_rows.end, 0)..old_cursor.end(&()),
 502                            );
 503                            new_transforms.push_or_extend(Transform::isomorphic(summary));
 504                        }
 505                        old_cursor.next(&());
 506                        new_transforms.append(
 507                            old_cursor.slice(
 508                                &TabPoint::new(next_edit.old_rows.start, 0),
 509                                Bias::Right,
 510                                &(),
 511                            ),
 512                            &(),
 513                        );
 514                    }
 515                } else {
 516                    if old_cursor.end(&()) > TabPoint::new(edit.old_rows.end, 0) {
 517                        let summary = self.tab_snapshot.text_summary_for_range(
 518                            TabPoint::new(edit.old_rows.end, 0)..old_cursor.end(&()),
 519                        );
 520                        new_transforms.push_or_extend(Transform::isomorphic(summary));
 521                    }
 522                    old_cursor.next(&());
 523                    new_transforms.append(old_cursor.suffix(&()), &());
 524                }
 525            }
 526        }
 527
 528        let old_snapshot = mem::replace(
 529            self,
 530            WrapSnapshot {
 531                tab_snapshot: new_tab_snapshot,
 532                transforms: new_transforms,
 533                interpolated: false,
 534            },
 535        );
 536        self.check_invariants();
 537        old_snapshot.compute_edits(tab_edits, self)
 538    }
 539
 540    fn compute_edits(&self, tab_edits: &[TabEdit], new_snapshot: &WrapSnapshot) -> Patch<u32> {
 541        let mut wrap_edits = Vec::new();
 542        let mut old_cursor = self.transforms.cursor::<TransformSummary>();
 543        let mut new_cursor = new_snapshot.transforms.cursor::<TransformSummary>();
 544        for mut tab_edit in tab_edits.iter().cloned() {
 545            tab_edit.old.start.0.column = 0;
 546            tab_edit.old.end.0 += Point::new(1, 0);
 547            tab_edit.new.start.0.column = 0;
 548            tab_edit.new.end.0 += Point::new(1, 0);
 549
 550            old_cursor.seek(&tab_edit.old.start, Bias::Right, &());
 551            let mut old_start = old_cursor.start().output.lines;
 552            old_start += tab_edit.old.start.0 - old_cursor.start().input.lines;
 553
 554            old_cursor.seek(&tab_edit.old.end, Bias::Right, &());
 555            let mut old_end = old_cursor.start().output.lines;
 556            old_end += tab_edit.old.end.0 - old_cursor.start().input.lines;
 557
 558            new_cursor.seek(&tab_edit.new.start, Bias::Right, &());
 559            let mut new_start = new_cursor.start().output.lines;
 560            new_start += tab_edit.new.start.0 - new_cursor.start().input.lines;
 561
 562            new_cursor.seek(&tab_edit.new.end, Bias::Right, &());
 563            let mut new_end = new_cursor.start().output.lines;
 564            new_end += tab_edit.new.end.0 - new_cursor.start().input.lines;
 565
 566            wrap_edits.push(WrapEdit {
 567                old: old_start.row..old_end.row,
 568                new: new_start.row..new_end.row,
 569            });
 570        }
 571
 572        consolidate_wrap_edits(&mut wrap_edits);
 573        Patch::new(wrap_edits)
 574    }
 575
 576    pub fn chunks<'a>(
 577        &'a self,
 578        rows: Range<u32>,
 579        language_aware: bool,
 580        highlights: Highlights<'a>,
 581    ) -> WrapChunks<'a> {
 582        let output_start = WrapPoint::new(rows.start, 0);
 583        let output_end = WrapPoint::new(rows.end, 0);
 584        let mut transforms = self.transforms.cursor::<(WrapPoint, TabPoint)>();
 585        transforms.seek(&output_start, Bias::Right, &());
 586        let mut input_start = TabPoint(transforms.start().1 .0);
 587        if transforms.item().map_or(false, |t| t.is_isomorphic()) {
 588            input_start.0 += output_start.0 - transforms.start().0 .0;
 589        }
 590        let input_end = self
 591            .to_tab_point(output_end)
 592            .min(self.tab_snapshot.max_point());
 593        WrapChunks {
 594            input_chunks: self.tab_snapshot.chunks(
 595                input_start..input_end,
 596                language_aware,
 597                highlights,
 598            ),
 599            input_chunk: Default::default(),
 600            output_position: output_start,
 601            max_output_row: rows.end,
 602            transforms,
 603        }
 604    }
 605
 606    pub fn max_point(&self) -> WrapPoint {
 607        WrapPoint(self.transforms.summary().output.lines)
 608    }
 609
 610    pub fn line_len(&self, row: u32) -> u32 {
 611        let mut cursor = self.transforms.cursor::<(WrapPoint, TabPoint)>();
 612        cursor.seek(&WrapPoint::new(row + 1, 0), Bias::Left, &());
 613        if cursor
 614            .item()
 615            .map_or(false, |transform| transform.is_isomorphic())
 616        {
 617            let overshoot = row - cursor.start().0.row();
 618            let tab_row = cursor.start().1.row() + overshoot;
 619            let tab_line_len = self.tab_snapshot.line_len(tab_row);
 620            if overshoot == 0 {
 621                cursor.start().0.column() + (tab_line_len - cursor.start().1.column())
 622            } else {
 623                tab_line_len
 624            }
 625        } else {
 626            cursor.start().0.column()
 627        }
 628    }
 629
 630    pub fn soft_wrap_indent(&self, row: u32) -> Option<u32> {
 631        let mut cursor = self.transforms.cursor::<WrapPoint>();
 632        cursor.seek(&WrapPoint::new(row + 1, 0), Bias::Right, &());
 633        cursor.item().and_then(|transform| {
 634            if transform.is_isomorphic() {
 635                None
 636            } else {
 637                Some(transform.summary.output.lines.column)
 638            }
 639        })
 640    }
 641
 642    pub fn longest_row(&self) -> u32 {
 643        self.transforms.summary().output.longest_row
 644    }
 645
 646    pub fn buffer_rows(&self, start_row: u32) -> WrapBufferRows {
 647        let mut transforms = self.transforms.cursor::<(WrapPoint, TabPoint)>();
 648        transforms.seek(&WrapPoint::new(start_row, 0), Bias::Left, &());
 649        let mut input_row = transforms.start().1.row();
 650        if transforms.item().map_or(false, |t| t.is_isomorphic()) {
 651            input_row += start_row - transforms.start().0.row();
 652        }
 653        let soft_wrapped = transforms.item().map_or(false, |t| !t.is_isomorphic());
 654        let mut input_buffer_rows = self.tab_snapshot.buffer_rows(input_row);
 655        let input_buffer_row = input_buffer_rows.next().unwrap();
 656        WrapBufferRows {
 657            transforms,
 658            input_buffer_row,
 659            input_buffer_rows,
 660            output_row: start_row,
 661            soft_wrapped,
 662            max_output_row: self.max_point().row(),
 663        }
 664    }
 665
 666    pub fn to_tab_point(&self, point: WrapPoint) -> TabPoint {
 667        let mut cursor = self.transforms.cursor::<(WrapPoint, TabPoint)>();
 668        cursor.seek(&point, Bias::Right, &());
 669        let mut tab_point = cursor.start().1 .0;
 670        if cursor.item().map_or(false, |t| t.is_isomorphic()) {
 671            tab_point += point.0 - cursor.start().0 .0;
 672        }
 673        TabPoint(tab_point)
 674    }
 675
 676    pub fn to_point(&self, point: WrapPoint, bias: Bias) -> Point {
 677        self.tab_snapshot.to_point(self.to_tab_point(point), bias)
 678    }
 679
 680    pub fn make_wrap_point(&self, point: Point, bias: Bias) -> WrapPoint {
 681        self.tab_point_to_wrap_point(self.tab_snapshot.make_tab_point(point, bias))
 682    }
 683
 684    pub fn tab_point_to_wrap_point(&self, point: TabPoint) -> WrapPoint {
 685        let mut cursor = self.transforms.cursor::<(TabPoint, WrapPoint)>();
 686        cursor.seek(&point, Bias::Right, &());
 687        WrapPoint(cursor.start().1 .0 + (point.0 - cursor.start().0 .0))
 688    }
 689
 690    pub fn clip_point(&self, mut point: WrapPoint, bias: Bias) -> WrapPoint {
 691        if bias == Bias::Left {
 692            let mut cursor = self.transforms.cursor::<WrapPoint>();
 693            cursor.seek(&point, Bias::Right, &());
 694            if cursor.item().map_or(false, |t| !t.is_isomorphic()) {
 695                point = *cursor.start();
 696                *point.column_mut() -= 1;
 697            }
 698        }
 699
 700        self.tab_point_to_wrap_point(self.tab_snapshot.clip_point(self.to_tab_point(point), bias))
 701    }
 702
 703    pub fn prev_row_boundary(&self, mut point: WrapPoint) -> u32 {
 704        if self.transforms.is_empty() {
 705            return 0;
 706        }
 707
 708        *point.column_mut() = 0;
 709
 710        let mut cursor = self.transforms.cursor::<(WrapPoint, TabPoint)>();
 711        cursor.seek(&point, Bias::Right, &());
 712        if cursor.item().is_none() {
 713            cursor.prev(&());
 714        }
 715
 716        while let Some(transform) = cursor.item() {
 717            if transform.is_isomorphic() && cursor.start().1.column() == 0 {
 718                return cmp::min(cursor.end(&()).0.row(), point.row());
 719            } else {
 720                cursor.prev(&());
 721            }
 722        }
 723
 724        unreachable!()
 725    }
 726
 727    pub fn next_row_boundary(&self, mut point: WrapPoint) -> Option<u32> {
 728        point.0 += Point::new(1, 0);
 729
 730        let mut cursor = self.transforms.cursor::<(WrapPoint, TabPoint)>();
 731        cursor.seek(&point, Bias::Right, &());
 732        while let Some(transform) = cursor.item() {
 733            if transform.is_isomorphic() && cursor.start().1.column() == 0 {
 734                return Some(cmp::max(cursor.start().0.row(), point.row()));
 735            } else {
 736                cursor.next(&());
 737            }
 738        }
 739
 740        None
 741    }
 742
 743    fn check_invariants(&self) {
 744        // todo!()
 745        // #[cfg(test)]
 746        // {
 747        //     assert_eq!(
 748        //         TabPoint::from(self.transforms.summary().input.lines),
 749        //         self.tab_snapshot.max_point()
 750        //     );
 751
 752        //     {
 753        //         let mut transforms = self.transforms.cursor::<()>().peekable();
 754        //         while let Some(transform) = transforms.next() {
 755        //             if let Some(next_transform) = transforms.peek() {
 756        //                 assert!(transform.is_isomorphic() != next_transform.is_isomorphic());
 757        //             }
 758        //         }
 759        //     }
 760
 761        //     let text = language::Rope::from(self.text().as_str());
 762        //     let mut input_buffer_rows = self.tab_snapshot.buffer_rows(0);
 763        //     let mut expected_buffer_rows = Vec::new();
 764        //     let mut prev_tab_row = 0;
 765        //     for display_row in 0..=self.max_point().row() {
 766        //         let tab_point = self.to_tab_point(WrapPoint::new(display_row, 0));
 767        //         if tab_point.row() == prev_tab_row && display_row != 0 {
 768        //             expected_buffer_rows.push(None);
 769        //         } else {
 770        //             expected_buffer_rows.push(input_buffer_rows.next().unwrap());
 771        //         }
 772
 773        //         prev_tab_row = tab_point.row();
 774        //         assert_eq!(self.line_len(display_row), text.line_len(display_row));
 775        //     }
 776
 777        //     for start_display_row in 0..expected_buffer_rows.len() {
 778        //         assert_eq!(
 779        //             self.buffer_rows(start_display_row as u32)
 780        //                 .collect::<Vec<_>>(),
 781        //             &expected_buffer_rows[start_display_row..],
 782        //             "invalid buffer_rows({}..)",
 783        //             start_display_row
 784        //         );
 785        //     }
 786        // }
 787    }
 788}
 789
 790impl<'a> Iterator for WrapChunks<'a> {
 791    type Item = Chunk<'a>;
 792
 793    fn next(&mut self) -> Option<Self::Item> {
 794        if self.output_position.row() >= self.max_output_row {
 795            return None;
 796        }
 797
 798        let transform = self.transforms.item()?;
 799        if let Some(display_text) = transform.display_text {
 800            let mut start_ix = 0;
 801            let mut end_ix = display_text.len();
 802            let mut summary = transform.summary.output.lines;
 803
 804            if self.output_position > self.transforms.start().0 {
 805                // Exclude newline starting prior to the desired row.
 806                start_ix = 1;
 807                summary.row = 0;
 808            } else if self.output_position.row() + 1 >= self.max_output_row {
 809                // Exclude soft indentation ending after the desired row.
 810                end_ix = 1;
 811                summary.column = 0;
 812            }
 813
 814            self.output_position.0 += summary;
 815            self.transforms.next(&());
 816            return Some(Chunk {
 817                text: &display_text[start_ix..end_ix],
 818                ..self.input_chunk
 819            });
 820        }
 821
 822        if self.input_chunk.text.is_empty() {
 823            self.input_chunk = self.input_chunks.next().unwrap();
 824        }
 825
 826        let mut input_len = 0;
 827        let transform_end = self.transforms.end(&()).0;
 828        for c in self.input_chunk.text.chars() {
 829            let char_len = c.len_utf8();
 830            input_len += char_len;
 831            if c == '\n' {
 832                *self.output_position.row_mut() += 1;
 833                *self.output_position.column_mut() = 0;
 834            } else {
 835                *self.output_position.column_mut() += char_len as u32;
 836            }
 837
 838            if self.output_position >= transform_end {
 839                self.transforms.next(&());
 840                break;
 841            }
 842        }
 843
 844        let (prefix, suffix) = self.input_chunk.text.split_at(input_len);
 845        self.input_chunk.text = suffix;
 846        Some(Chunk {
 847            text: prefix,
 848            ..self.input_chunk
 849        })
 850    }
 851}
 852
 853impl<'a> Iterator for WrapBufferRows<'a> {
 854    type Item = Option<u32>;
 855
 856    fn next(&mut self) -> Option<Self::Item> {
 857        if self.output_row > self.max_output_row {
 858            return None;
 859        }
 860
 861        let buffer_row = self.input_buffer_row;
 862        let soft_wrapped = self.soft_wrapped;
 863
 864        self.output_row += 1;
 865        self.transforms
 866            .seek_forward(&WrapPoint::new(self.output_row, 0), Bias::Left, &());
 867        if self.transforms.item().map_or(false, |t| t.is_isomorphic()) {
 868            self.input_buffer_row = self.input_buffer_rows.next().unwrap();
 869            self.soft_wrapped = false;
 870        } else {
 871            self.soft_wrapped = true;
 872        }
 873
 874        Some(if soft_wrapped { None } else { buffer_row })
 875    }
 876}
 877
 878impl Transform {
 879    fn isomorphic(summary: TextSummary) -> Self {
 880        #[cfg(test)]
 881        assert!(!summary.lines.is_zero());
 882
 883        Self {
 884            summary: TransformSummary {
 885                input: summary.clone(),
 886                output: summary,
 887            },
 888            display_text: None,
 889        }
 890    }
 891
 892    fn wrap(indent: u32) -> Self {
 893        lazy_static! {
 894            static ref WRAP_TEXT: String = {
 895                let mut wrap_text = String::new();
 896                wrap_text.push('\n');
 897                wrap_text.extend((0..LineWrapper::MAX_INDENT as usize).map(|_| ' '));
 898                wrap_text
 899            };
 900        }
 901
 902        Self {
 903            summary: TransformSummary {
 904                input: TextSummary::default(),
 905                output: TextSummary {
 906                    lines: Point::new(1, indent),
 907                    first_line_chars: 0,
 908                    last_line_chars: indent,
 909                    longest_row: 1,
 910                    longest_row_chars: indent,
 911                },
 912            },
 913            display_text: Some(&WRAP_TEXT[..1 + indent as usize]),
 914        }
 915    }
 916
 917    fn is_isomorphic(&self) -> bool {
 918        self.display_text.is_none()
 919    }
 920}
 921
 922impl sum_tree::Item for Transform {
 923    type Summary = TransformSummary;
 924
 925    fn summary(&self) -> Self::Summary {
 926        self.summary.clone()
 927    }
 928}
 929
 930fn push_isomorphic(transforms: &mut Vec<Transform>, summary: TextSummary) {
 931    if let Some(last_transform) = transforms.last_mut() {
 932        if last_transform.is_isomorphic() {
 933            last_transform.summary.input += &summary;
 934            last_transform.summary.output += &summary;
 935            return;
 936        }
 937    }
 938    transforms.push(Transform::isomorphic(summary));
 939}
 940
 941trait SumTreeExt {
 942    fn push_or_extend(&mut self, transform: Transform);
 943}
 944
 945impl SumTreeExt for SumTree<Transform> {
 946    fn push_or_extend(&mut self, transform: Transform) {
 947        let mut transform = Some(transform);
 948        self.update_last(
 949            |last_transform| {
 950                if last_transform.is_isomorphic() && transform.as_ref().unwrap().is_isomorphic() {
 951                    let transform = transform.take().unwrap();
 952                    last_transform.summary.input += &transform.summary.input;
 953                    last_transform.summary.output += &transform.summary.output;
 954                }
 955            },
 956            &(),
 957        );
 958
 959        if let Some(transform) = transform {
 960            self.push(transform, &());
 961        }
 962    }
 963}
 964
 965impl WrapPoint {
 966    pub fn new(row: u32, column: u32) -> Self {
 967        Self(Point::new(row, column))
 968    }
 969
 970    pub fn row(self) -> u32 {
 971        self.0.row
 972    }
 973
 974    pub fn row_mut(&mut self) -> &mut u32 {
 975        &mut self.0.row
 976    }
 977
 978    pub fn column(self) -> u32 {
 979        self.0.column
 980    }
 981
 982    pub fn column_mut(&mut self) -> &mut u32 {
 983        &mut self.0.column
 984    }
 985}
 986
 987impl sum_tree::Summary for TransformSummary {
 988    type Context = ();
 989
 990    fn add_summary(&mut self, other: &Self, _: &()) {
 991        self.input += &other.input;
 992        self.output += &other.output;
 993    }
 994}
 995
 996impl<'a> sum_tree::Dimension<'a, TransformSummary> for TabPoint {
 997    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
 998        self.0 += summary.input.lines;
 999    }
1000}
1001
1002impl<'a> sum_tree::SeekTarget<'a, TransformSummary, TransformSummary> for TabPoint {
1003    fn cmp(&self, cursor_location: &TransformSummary, _: &()) -> std::cmp::Ordering {
1004        Ord::cmp(&self.0, &cursor_location.input.lines)
1005    }
1006}
1007
1008impl<'a> sum_tree::Dimension<'a, TransformSummary> for WrapPoint {
1009    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1010        self.0 += summary.output.lines;
1011    }
1012}
1013
1014fn consolidate_wrap_edits(edits: &mut Vec<WrapEdit>) {
1015    let mut i = 1;
1016    while i < edits.len() {
1017        let edit = edits[i].clone();
1018        let prev_edit = &mut edits[i - 1];
1019        if prev_edit.old.end >= edit.old.start {
1020            prev_edit.old.end = edit.old.end;
1021            prev_edit.new.end = edit.new.end;
1022            edits.remove(i);
1023            continue;
1024        }
1025        i += 1;
1026    }
1027}
1028
1029// #[cfg(test)]
1030// mod tests {
1031//     use super::*;
1032//     use crate::{
1033//         display_map::{fold_map::FoldMap, inlay_map::InlayMap, tab_map::TabMap},
1034//         MultiBuffer,
1035//     };
1036//     use gpui::test::observe;
1037//     use rand::prelude::*;
1038//     use settings::SettingsStore;
1039//     use smol::stream::StreamExt;
1040//     use std::{cmp, env, num::NonZeroU32};
1041//     use text::Rope;
1042
1043//     #[gpui::test(iterations = 100)]
1044//     async fn test_random_wraps(cx: &mut gpui::TestAppContext, mut rng: StdRng) {
1045//         init_test(cx);
1046
1047//         cx.foreground().set_block_on_ticks(0..=50);
1048//         let operations = env::var("OPERATIONS")
1049//             .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
1050//             .unwrap_or(10);
1051
1052//         let font_cache = cx.font_cache().clone();
1053//         let font_system = cx.platform().fonts();
1054//         let mut wrap_width = if rng.gen_bool(0.1) {
1055//             None
1056//         } else {
1057//             Some(rng.gen_range(0.0..=1000.0))
1058//         };
1059//         let tab_size = NonZeroU32::new(rng.gen_range(1..=4)).unwrap();
1060//         let family_id = font_cache
1061//             .load_family(&["Helvetica"], &Default::default())
1062//             .unwrap();
1063//         let font_id = font_cache
1064//             .select_font(family_id, &Default::default())
1065//             .unwrap();
1066//         let font_size = 14.0;
1067
1068//         log::info!("Tab size: {}", tab_size);
1069//         log::info!("Wrap width: {:?}", wrap_width);
1070
1071//         let buffer = cx.update(|cx| {
1072//             if rng.gen() {
1073//                 MultiBuffer::build_random(&mut rng, cx)
1074//             } else {
1075//                 let len = rng.gen_range(0..10);
1076//                 let text = util::RandomCharIter::new(&mut rng)
1077//                     .take(len)
1078//                     .collect::<String>();
1079//                 MultiBuffer::build_simple(&text, cx)
1080//             }
1081//         });
1082//         let mut buffer_snapshot = buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx));
1083//         log::info!("Buffer text: {:?}", buffer_snapshot.text());
1084//         let (mut inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
1085//         log::info!("InlayMap text: {:?}", inlay_snapshot.text());
1086//         let (mut fold_map, fold_snapshot) = FoldMap::new(inlay_snapshot.clone());
1087//         log::info!("FoldMap text: {:?}", fold_snapshot.text());
1088//         let (mut tab_map, _) = TabMap::new(fold_snapshot.clone(), tab_size);
1089//         let tabs_snapshot = tab_map.set_max_expansion_column(32);
1090//         log::info!("TabMap text: {:?}", tabs_snapshot.text());
1091
1092//         let mut line_wrapper = LineWrapper::new(font_id, font_size, font_system);
1093//         let unwrapped_text = tabs_snapshot.text();
1094//         let expected_text = wrap_text(&unwrapped_text, wrap_width, &mut line_wrapper);
1095
1096//         let (wrap_map, _) =
1097//             cx.update(|cx| WrapMap::new(tabs_snapshot.clone(), font_id, font_size, wrap_width, cx));
1098//         let mut notifications = observe(&wrap_map, cx);
1099
1100//         if wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1101//             notifications.next().await.unwrap();
1102//         }
1103
1104//         let (initial_snapshot, _) = wrap_map.update(cx, |map, cx| {
1105//             assert!(!map.is_rewrapping());
1106//             map.sync(tabs_snapshot.clone(), Vec::new(), cx)
1107//         });
1108
1109//         let actual_text = initial_snapshot.text();
1110//         assert_eq!(
1111//             actual_text, expected_text,
1112//             "unwrapped text is: {:?}",
1113//             unwrapped_text
1114//         );
1115//         log::info!("Wrapped text: {:?}", actual_text);
1116
1117//         let mut next_inlay_id = 0;
1118//         let mut edits = Vec::new();
1119//         for _i in 0..operations {
1120//             log::info!("{} ==============================================", _i);
1121
1122//             let mut buffer_edits = Vec::new();
1123//             match rng.gen_range(0..=100) {
1124//                 0..=19 => {
1125//                     wrap_width = if rng.gen_bool(0.2) {
1126//                         None
1127//                     } else {
1128//                         Some(rng.gen_range(0.0..=1000.0))
1129//                     };
1130//                     log::info!("Setting wrap width to {:?}", wrap_width);
1131//                     wrap_map.update(cx, |map, cx| map.set_wrap_width(wrap_width, cx));
1132//                 }
1133//                 20..=39 => {
1134//                     for (fold_snapshot, fold_edits) in fold_map.randomly_mutate(&mut rng) {
1135//                         let (tabs_snapshot, tab_edits) =
1136//                             tab_map.sync(fold_snapshot, fold_edits, tab_size);
1137//                         let (mut snapshot, wrap_edits) =
1138//                             wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot, tab_edits, cx));
1139//                         snapshot.check_invariants();
1140//                         snapshot.verify_chunks(&mut rng);
1141//                         edits.push((snapshot, wrap_edits));
1142//                     }
1143//                 }
1144//                 40..=59 => {
1145//                     let (inlay_snapshot, inlay_edits) =
1146//                         inlay_map.randomly_mutate(&mut next_inlay_id, &mut rng);
1147//                     let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1148//                     let (tabs_snapshot, tab_edits) =
1149//                         tab_map.sync(fold_snapshot, fold_edits, tab_size);
1150//                     let (mut snapshot, wrap_edits) =
1151//                         wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot, tab_edits, cx));
1152//                     snapshot.check_invariants();
1153//                     snapshot.verify_chunks(&mut rng);
1154//                     edits.push((snapshot, wrap_edits));
1155//                 }
1156//                 _ => {
1157//                     buffer.update(cx, |buffer, cx| {
1158//                         let subscription = buffer.subscribe();
1159//                         let edit_count = rng.gen_range(1..=5);
1160//                         buffer.randomly_mutate(&mut rng, edit_count, cx);
1161//                         buffer_snapshot = buffer.snapshot(cx);
1162//                         buffer_edits.extend(subscription.consume());
1163//                     });
1164//                 }
1165//             }
1166
1167//             log::info!("Buffer text: {:?}", buffer_snapshot.text());
1168//             let (inlay_snapshot, inlay_edits) =
1169//                 inlay_map.sync(buffer_snapshot.clone(), buffer_edits);
1170//             log::info!("InlayMap text: {:?}", inlay_snapshot.text());
1171//             let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1172//             log::info!("FoldMap text: {:?}", fold_snapshot.text());
1173//             let (tabs_snapshot, tab_edits) = tab_map.sync(fold_snapshot, fold_edits, tab_size);
1174//             log::info!("TabMap text: {:?}", tabs_snapshot.text());
1175
1176//             let unwrapped_text = tabs_snapshot.text();
1177//             let expected_text = wrap_text(&unwrapped_text, wrap_width, &mut line_wrapper);
1178//             let (mut snapshot, wrap_edits) =
1179//                 wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot.clone(), tab_edits, cx));
1180//             snapshot.check_invariants();
1181//             snapshot.verify_chunks(&mut rng);
1182//             edits.push((snapshot, wrap_edits));
1183
1184//             if wrap_map.read_with(cx, |map, _| map.is_rewrapping()) && rng.gen_bool(0.4) {
1185//                 log::info!("Waiting for wrapping to finish");
1186//                 while wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1187//                     notifications.next().await.unwrap();
1188//                 }
1189//                 wrap_map.read_with(cx, |map, _| assert!(map.pending_edits.is_empty()));
1190//             }
1191
1192//             if !wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1193//                 let (mut wrapped_snapshot, wrap_edits) =
1194//                     wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot, Vec::new(), cx));
1195//                 let actual_text = wrapped_snapshot.text();
1196//                 let actual_longest_row = wrapped_snapshot.longest_row();
1197//                 log::info!("Wrapping finished: {:?}", actual_text);
1198//                 wrapped_snapshot.check_invariants();
1199//                 wrapped_snapshot.verify_chunks(&mut rng);
1200//                 edits.push((wrapped_snapshot.clone(), wrap_edits));
1201//                 assert_eq!(
1202//                     actual_text, expected_text,
1203//                     "unwrapped text is: {:?}",
1204//                     unwrapped_text
1205//                 );
1206
1207//                 let mut summary = TextSummary::default();
1208//                 for (ix, item) in wrapped_snapshot
1209//                     .transforms
1210//                     .items(&())
1211//                     .into_iter()
1212//                     .enumerate()
1213//                 {
1214//                     summary += &item.summary.output;
1215//                     log::info!("{} summary: {:?}", ix, item.summary.output,);
1216//                 }
1217
1218//                 if tab_size.get() == 1
1219//                     || !wrapped_snapshot
1220//                         .tab_snapshot
1221//                         .fold_snapshot
1222//                         .text()
1223//                         .contains('\t')
1224//                 {
1225//                     let mut expected_longest_rows = Vec::new();
1226//                     let mut longest_line_len = -1;
1227//                     for (row, line) in expected_text.split('\n').enumerate() {
1228//                         let line_char_count = line.chars().count() as isize;
1229//                         if line_char_count > longest_line_len {
1230//                             expected_longest_rows.clear();
1231//                             longest_line_len = line_char_count;
1232//                         }
1233//                         if line_char_count >= longest_line_len {
1234//                             expected_longest_rows.push(row as u32);
1235//                         }
1236//                     }
1237
1238//                     assert!(
1239//                         expected_longest_rows.contains(&actual_longest_row),
1240//                         "incorrect longest row {}. expected {:?} with length {}",
1241//                         actual_longest_row,
1242//                         expected_longest_rows,
1243//                         longest_line_len,
1244//                     )
1245//                 }
1246//             }
1247//         }
1248
1249//         let mut initial_text = Rope::from(initial_snapshot.text().as_str());
1250//         for (snapshot, patch) in edits {
1251//             let snapshot_text = Rope::from(snapshot.text().as_str());
1252//             for edit in &patch {
1253//                 let old_start = initial_text.point_to_offset(Point::new(edit.new.start, 0));
1254//                 let old_end = initial_text.point_to_offset(cmp::min(
1255//                     Point::new(edit.new.start + edit.old.len() as u32, 0),
1256//                     initial_text.max_point(),
1257//                 ));
1258//                 let new_start = snapshot_text.point_to_offset(Point::new(edit.new.start, 0));
1259//                 let new_end = snapshot_text.point_to_offset(cmp::min(
1260//                     Point::new(edit.new.end, 0),
1261//                     snapshot_text.max_point(),
1262//                 ));
1263//                 let new_text = snapshot_text
1264//                     .chunks_in_range(new_start..new_end)
1265//                     .collect::<String>();
1266
1267//                 initial_text.replace(old_start..old_end, &new_text);
1268//             }
1269//             assert_eq!(initial_text.to_string(), snapshot_text.to_string());
1270//         }
1271
1272//         if wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1273//             log::info!("Waiting for wrapping to finish");
1274//             while wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1275//                 notifications.next().await.unwrap();
1276//             }
1277//         }
1278//         wrap_map.read_with(cx, |map, _| assert!(map.pending_edits.is_empty()));
1279//     }
1280
1281//     fn init_test(cx: &mut gpui::TestAppContext) {
1282//         cx.foreground().forbid_parking();
1283//         cx.update(|cx| {
1284//             cx.set_global(SettingsStore::test(cx));
1285//             theme::init((), cx);
1286//         });
1287//     }
1288
1289//     fn wrap_text(
1290//         unwrapped_text: &str,
1291//         wrap_width: Option<f32>,
1292//         line_wrapper: &mut LineWrapper,
1293//     ) -> String {
1294//         if let Some(wrap_width) = wrap_width {
1295//             let mut wrapped_text = String::new();
1296//             for (row, line) in unwrapped_text.split('\n').enumerate() {
1297//                 if row > 0 {
1298//                     wrapped_text.push('\n')
1299//                 }
1300
1301//                 let mut prev_ix = 0;
1302//                 for boundary in line_wrapper.wrap_line(line, wrap_width) {
1303//                     wrapped_text.push_str(&line[prev_ix..boundary.ix]);
1304//                     wrapped_text.push('\n');
1305//                     wrapped_text.push_str(&" ".repeat(boundary.next_indent as usize));
1306//                     prev_ix = boundary.ix;
1307//                 }
1308//                 wrapped_text.push_str(&line[prev_ix..]);
1309//             }
1310//             wrapped_text
1311//         } else {
1312//             unwrapped_text.to_string()
1313//         }
1314//     }
1315
1316//     impl WrapSnapshot {
1317//         pub fn text(&self) -> String {
1318//             self.text_chunks(0).collect()
1319//         }
1320
1321//         pub fn text_chunks(&self, wrap_row: u32) -> impl Iterator<Item = &str> {
1322//             self.chunks(
1323//                 wrap_row..self.max_point().row() + 1,
1324//                 false,
1325//                 Highlights::default(),
1326//             )
1327//             .map(|h| h.text)
1328//         }
1329
1330//         fn verify_chunks(&mut self, rng: &mut impl Rng) {
1331//             for _ in 0..5 {
1332//                 let mut end_row = rng.gen_range(0..=self.max_point().row());
1333//                 let start_row = rng.gen_range(0..=end_row);
1334//                 end_row += 1;
1335
1336//                 let mut expected_text = self.text_chunks(start_row).collect::<String>();
1337//                 if expected_text.ends_with('\n') {
1338//                     expected_text.push('\n');
1339//                 }
1340//                 let mut expected_text = expected_text
1341//                     .lines()
1342//                     .take((end_row - start_row) as usize)
1343//                     .collect::<Vec<_>>()
1344//                     .join("\n");
1345//                 if end_row <= self.max_point().row() {
1346//                     expected_text.push('\n');
1347//                 }
1348
1349//                 let actual_text = self
1350//                     .chunks(start_row..end_row, true, Highlights::default())
1351//                     .map(|c| c.text)
1352//                     .collect::<String>();
1353//                 assert_eq!(
1354//                     expected_text,
1355//                     actual_text,
1356//                     "chunks != highlighted_chunks for rows {:?}",
1357//                     start_row..end_row
1358//                 );
1359//             }
1360//         }
1361//     }
1362// }