wrap_map.rs

   1use super::{
   2    Highlights,
   3    dimensions::RowDelta,
   4    fold_map::{Chunk, FoldRows},
   5    tab_map::{self, TabEdit, TabPoint, TabSnapshot},
   6};
   7use gpui::{App, AppContext as _, Context, Entity, Font, LineWrapper, Pixels, Task};
   8use language::Point;
   9use multi_buffer::{MultiBufferSnapshot, RowInfo};
  10use smol::future::yield_now;
  11use std::{cmp, collections::VecDeque, mem, ops::Range, sync::LazyLock, time::Duration};
  12use sum_tree::{Bias, Cursor, Dimensions, SumTree};
  13use text::Patch;
  14
  15pub use super::tab_map::TextSummary;
  16pub type WrapEdit = text::Edit<WrapRow>;
  17pub type WrapPatch = text::Patch<WrapRow>;
  18
  19#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  20pub struct WrapRow(pub u32);
  21
  22const WRAP_YIELD_ROW_INTERVAL: usize = 100;
  23
  24impl_for_row_types! {
  25    WrapRow => RowDelta
  26}
  27
  28/// Handles soft wrapping of text.
  29///
  30/// See the [`display_map` module documentation](crate::display_map) for more information.
  31pub struct WrapMap {
  32    snapshot: WrapSnapshot,
  33    pending_edits: VecDeque<(TabSnapshot, Vec<TabEdit>)>,
  34    interpolated_edits: WrapPatch,
  35    edits_since_sync: WrapPatch,
  36    wrap_width: Option<Pixels>,
  37    background_task: Option<Task<()>>,
  38    font_with_size: (Font, Pixels),
  39}
  40
  41#[derive(Clone)]
  42pub struct WrapSnapshot {
  43    pub(super) tab_snapshot: TabSnapshot,
  44    transforms: SumTree<Transform>,
  45    interpolated: bool,
  46}
  47
  48impl std::ops::Deref for WrapSnapshot {
  49    type Target = TabSnapshot;
  50
  51    fn deref(&self) -> &Self::Target {
  52        &self.tab_snapshot
  53    }
  54}
  55
  56#[derive(Clone, Debug, Default, Eq, PartialEq)]
  57struct Transform {
  58    summary: TransformSummary,
  59    display_text: Option<&'static str>,
  60}
  61
  62#[derive(Clone, Debug, Default, Eq, PartialEq)]
  63struct TransformSummary {
  64    input: TextSummary,
  65    output: TextSummary,
  66}
  67
  68#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  69pub struct WrapPoint(pub Point);
  70
  71pub struct WrapChunks<'a> {
  72    input_chunks: tab_map::TabChunks<'a>,
  73    input_chunk: Chunk<'a>,
  74    output_position: WrapPoint,
  75    max_output_row: WrapRow,
  76    transforms: Cursor<'a, 'static, Transform, Dimensions<WrapPoint, TabPoint>>,
  77    snapshot: &'a WrapSnapshot,
  78}
  79
  80#[derive(Clone)]
  81pub struct WrapRows<'a> {
  82    input_buffer_rows: FoldRows<'a>,
  83    input_buffer_row: RowInfo,
  84    output_row: WrapRow,
  85    soft_wrapped: bool,
  86    max_output_row: WrapRow,
  87    transforms: Cursor<'a, 'static, Transform, Dimensions<WrapPoint, TabPoint>>,
  88}
  89
  90impl WrapRows<'_> {
  91    #[ztracing::instrument(skip_all)]
  92    pub(crate) fn seek(&mut self, start_row: WrapRow) {
  93        self.transforms
  94            .seek(&WrapPoint::new(start_row, 0), Bias::Left);
  95        let mut input_row = self.transforms.start().1.row();
  96        if self.transforms.item().is_some_and(|t| t.is_isomorphic()) {
  97            input_row += (start_row - self.transforms.start().0.row()).0;
  98        }
  99        self.soft_wrapped = self.transforms.item().is_some_and(|t| !t.is_isomorphic());
 100        self.input_buffer_rows.seek(input_row);
 101        self.input_buffer_row = self.input_buffer_rows.next().unwrap();
 102        self.output_row = start_row;
 103    }
 104}
 105
 106impl WrapMap {
 107    #[ztracing::instrument(skip_all)]
 108    pub fn new(
 109        tab_snapshot: TabSnapshot,
 110        font: Font,
 111        font_size: Pixels,
 112        wrap_width: Option<Pixels>,
 113        cx: &mut App,
 114    ) -> (Entity<Self>, WrapSnapshot) {
 115        let handle = cx.new(|cx| {
 116            let mut this = Self {
 117                font_with_size: (font, font_size),
 118                wrap_width: None,
 119                pending_edits: Default::default(),
 120                interpolated_edits: Default::default(),
 121                edits_since_sync: Default::default(),
 122                snapshot: WrapSnapshot::new(tab_snapshot),
 123                background_task: None,
 124            };
 125            this.set_wrap_width(wrap_width, cx);
 126            mem::take(&mut this.edits_since_sync);
 127            this
 128        });
 129        let snapshot = handle.read(cx).snapshot.clone();
 130        (handle, snapshot)
 131    }
 132
 133    #[cfg(test)]
 134    pub fn is_rewrapping(&self) -> bool {
 135        self.background_task.is_some()
 136    }
 137
 138    #[ztracing::instrument(skip_all)]
 139    pub fn sync(
 140        &mut self,
 141        tab_snapshot: TabSnapshot,
 142        edits: Vec<TabEdit>,
 143        cx: &mut Context<Self>,
 144    ) -> (WrapSnapshot, WrapPatch) {
 145        if self.wrap_width.is_some() {
 146            self.pending_edits.push_back((tab_snapshot, edits));
 147            self.flush_edits(cx);
 148        } else {
 149            self.edits_since_sync = self
 150                .edits_since_sync
 151                .compose(self.snapshot.interpolate(tab_snapshot, &edits));
 152            self.snapshot.interpolated = false;
 153        }
 154
 155        (self.snapshot.clone(), mem::take(&mut self.edits_since_sync))
 156    }
 157
 158    #[ztracing::instrument(skip_all)]
 159    pub fn set_font_with_size(
 160        &mut self,
 161        font: Font,
 162        font_size: Pixels,
 163        cx: &mut Context<Self>,
 164    ) -> bool {
 165        let font_with_size = (font, font_size);
 166
 167        if font_with_size == self.font_with_size {
 168            false
 169        } else {
 170            self.font_with_size = font_with_size;
 171            self.rewrap(cx);
 172            true
 173        }
 174    }
 175
 176    #[ztracing::instrument(skip_all)]
 177    pub fn set_wrap_width(&mut self, wrap_width: Option<Pixels>, cx: &mut Context<Self>) -> bool {
 178        if wrap_width == self.wrap_width {
 179            return false;
 180        }
 181
 182        self.wrap_width = wrap_width;
 183        self.rewrap(cx);
 184        true
 185    }
 186
 187    #[ztracing::instrument(skip_all)]
 188    fn rewrap(&mut self, cx: &mut Context<Self>) {
 189        self.background_task.take();
 190        self.interpolated_edits.clear();
 191        self.pending_edits.clear();
 192
 193        if let Some(wrap_width) = self.wrap_width {
 194            let mut new_snapshot = self.snapshot.clone();
 195
 196            let text_system = cx.text_system();
 197            let (font, font_size) = self.font_with_size.clone();
 198            let mut line_wrapper = text_system.line_wrapper(font, font_size);
 199            let tab_snapshot = new_snapshot.tab_snapshot.clone();
 200            let total_rows = tab_snapshot.max_point().row() as usize + 1;
 201            let range = TabPoint::zero()..tab_snapshot.max_point();
 202            let tab_edits = [TabEdit {
 203                old: range.clone(),
 204                new: range,
 205            }];
 206
 207            if total_rows < WRAP_YIELD_ROW_INTERVAL {
 208                let edits = smol::block_on(new_snapshot.update(
 209                    tab_snapshot,
 210                    &tab_edits,
 211                    wrap_width,
 212                    &mut line_wrapper,
 213                ));
 214                self.snapshot = new_snapshot;
 215                self.edits_since_sync = self.edits_since_sync.compose(&edits);
 216            } else {
 217                let task = cx.background_spawn(async move {
 218                    let edits = new_snapshot
 219                        .update(tab_snapshot, &tab_edits, wrap_width, &mut line_wrapper)
 220                        .await;
 221                    (new_snapshot, edits)
 222                });
 223
 224                match cx
 225                    .foreground_executor()
 226                    .block_with_timeout(Duration::from_millis(5), task)
 227                {
 228                    Ok((snapshot, edits)) => {
 229                        self.snapshot = snapshot;
 230                        self.edits_since_sync = self.edits_since_sync.compose(&edits);
 231                    }
 232                    Err(wrap_task) => {
 233                        self.background_task = Some(cx.spawn(async move |this, cx| {
 234                            let (snapshot, edits) = wrap_task.await;
 235                            this.update(cx, |this, cx| {
 236                                this.snapshot = snapshot;
 237                                this.edits_since_sync = this
 238                                    .edits_since_sync
 239                                    .compose(mem::take(&mut this.interpolated_edits).invert())
 240                                    .compose(&edits);
 241                                this.background_task = None;
 242                                this.flush_edits(cx);
 243                                cx.notify();
 244                            })
 245                            .ok();
 246                        }));
 247                    }
 248                }
 249            }
 250        } else {
 251            let old_rows = self.snapshot.transforms.summary().output.lines.row + 1;
 252            self.snapshot.transforms = SumTree::default();
 253            let summary = self.snapshot.tab_snapshot.text_summary();
 254            if !summary.lines.is_zero() {
 255                self.snapshot
 256                    .transforms
 257                    .push(Transform::isomorphic(summary), ());
 258            }
 259            let new_rows = self.snapshot.transforms.summary().output.lines.row + 1;
 260            self.snapshot.interpolated = false;
 261            self.edits_since_sync = self.edits_since_sync.compose(Patch::new(vec![WrapEdit {
 262                old: WrapRow(0)..WrapRow(old_rows),
 263                new: WrapRow(0)..WrapRow(new_rows),
 264            }]));
 265        }
 266    }
 267
 268    #[ztracing::instrument(skip_all)]
 269    fn flush_edits(&mut self, cx: &mut Context<Self>) {
 270        if !self.snapshot.interpolated {
 271            let mut to_remove_len = 0;
 272            for (tab_snapshot, _) in &self.pending_edits {
 273                if tab_snapshot.version <= self.snapshot.tab_snapshot.version {
 274                    to_remove_len += 1;
 275                } else {
 276                    break;
 277                }
 278            }
 279            self.pending_edits.drain(..to_remove_len);
 280        }
 281
 282        if self.pending_edits.is_empty() {
 283            return;
 284        }
 285
 286        if let Some(wrap_width) = self.wrap_width
 287            && self.background_task.is_none()
 288        {
 289            let mut pending_edits = self.pending_edits.clone();
 290            let mut snapshot = self.snapshot.clone();
 291            let text_system = cx.text_system().clone();
 292            let (font, font_size) = self.font_with_size.clone();
 293            let mut line_wrapper = text_system.line_wrapper(font, font_size);
 294
 295            if pending_edits.len() == 1
 296                && let Some((_, tab_edits)) = pending_edits.back()
 297                && let [edit] = &**tab_edits
 298                && ((edit.new.end.row().saturating_sub(edit.new.start.row()) + 1) as usize)
 299                    < WRAP_YIELD_ROW_INTERVAL
 300                && let Some((tab_snapshot, tab_edits)) = pending_edits.pop_back()
 301            {
 302                let wrap_edits = smol::block_on(snapshot.update(
 303                    tab_snapshot,
 304                    &tab_edits,
 305                    wrap_width,
 306                    &mut line_wrapper,
 307                ));
 308                self.snapshot = snapshot;
 309                self.edits_since_sync = self.edits_since_sync.compose(&wrap_edits);
 310            } else {
 311                let update_task = cx.background_spawn(async move {
 312                    let mut edits = Patch::default();
 313                    for (tab_snapshot, tab_edits) in pending_edits {
 314                        let wrap_edits = snapshot
 315                            .update(tab_snapshot, &tab_edits, wrap_width, &mut line_wrapper)
 316                            .await;
 317                        edits = edits.compose(&wrap_edits);
 318                    }
 319                    (snapshot, edits)
 320                });
 321
 322                match cx
 323                    .foreground_executor()
 324                    .block_with_timeout(Duration::from_millis(1), update_task)
 325                {
 326                    Ok((snapshot, output_edits)) => {
 327                        self.snapshot = snapshot;
 328                        self.edits_since_sync = self.edits_since_sync.compose(&output_edits);
 329                    }
 330                    Err(update_task) => {
 331                        self.background_task = Some(cx.spawn(async move |this, cx| {
 332                            let (snapshot, edits) = update_task.await;
 333                            this.update(cx, |this, cx| {
 334                                this.snapshot = snapshot;
 335                                this.edits_since_sync = this
 336                                    .edits_since_sync
 337                                    .compose(mem::take(&mut this.interpolated_edits).invert())
 338                                    .compose(&edits);
 339                                this.background_task = None;
 340                                this.flush_edits(cx);
 341                                cx.notify();
 342                            })
 343                            .ok();
 344                        }));
 345                    }
 346                }
 347            }
 348        }
 349
 350        let was_interpolated = self.snapshot.interpolated;
 351        let mut to_remove_len = 0;
 352        for (tab_snapshot, edits) in &self.pending_edits {
 353            if tab_snapshot.version <= self.snapshot.tab_snapshot.version {
 354                to_remove_len += 1;
 355            } else {
 356                let interpolated_edits = self.snapshot.interpolate(tab_snapshot.clone(), edits);
 357                self.edits_since_sync = self.edits_since_sync.compose(&interpolated_edits);
 358                self.interpolated_edits = self.interpolated_edits.compose(&interpolated_edits);
 359            }
 360        }
 361
 362        if !was_interpolated {
 363            self.pending_edits.drain(..to_remove_len);
 364        }
 365    }
 366}
 367
 368impl WrapSnapshot {
 369    #[ztracing::instrument(skip_all)]
 370    fn new(tab_snapshot: TabSnapshot) -> Self {
 371        let mut transforms = SumTree::default();
 372        let extent = tab_snapshot.text_summary();
 373        if !extent.lines.is_zero() {
 374            transforms.push(Transform::isomorphic(extent), ());
 375        }
 376        Self {
 377            transforms,
 378            tab_snapshot,
 379            interpolated: true,
 380        }
 381    }
 382
 383    #[ztracing::instrument(skip_all)]
 384    pub fn buffer_snapshot(&self) -> &MultiBufferSnapshot {
 385        self.tab_snapshot.buffer_snapshot()
 386    }
 387
 388    #[ztracing::instrument(skip_all)]
 389    fn interpolate(&mut self, new_tab_snapshot: TabSnapshot, tab_edits: &[TabEdit]) -> WrapPatch {
 390        let mut new_transforms;
 391        if tab_edits.is_empty() {
 392            new_transforms = self.transforms.clone();
 393        } else {
 394            let mut old_cursor = self.transforms.cursor::<TabPoint>(());
 395
 396            let mut tab_edits_iter = tab_edits.iter().peekable();
 397            new_transforms =
 398                old_cursor.slice(&tab_edits_iter.peek().unwrap().old.start, Bias::Right);
 399
 400            while let Some(edit) = tab_edits_iter.next() {
 401                if edit.new.start > TabPoint::from(new_transforms.summary().input.lines) {
 402                    let summary = new_tab_snapshot.text_summary_for_range(
 403                        TabPoint::from(new_transforms.summary().input.lines)..edit.new.start,
 404                    );
 405                    new_transforms.push_or_extend(Transform::isomorphic(summary));
 406                }
 407
 408                if !edit.new.is_empty() {
 409                    new_transforms.push_or_extend(Transform::isomorphic(
 410                        new_tab_snapshot.text_summary_for_range(edit.new.clone()),
 411                    ));
 412                }
 413
 414                old_cursor.seek_forward(&edit.old.end, Bias::Right);
 415                if let Some(next_edit) = tab_edits_iter.peek() {
 416                    if next_edit.old.start > old_cursor.end() {
 417                        if old_cursor.end() > edit.old.end {
 418                            let summary = self
 419                                .tab_snapshot
 420                                .text_summary_for_range(edit.old.end..old_cursor.end());
 421                            new_transforms.push_or_extend(Transform::isomorphic(summary));
 422                        }
 423
 424                        old_cursor.next();
 425                        new_transforms
 426                            .append(old_cursor.slice(&next_edit.old.start, Bias::Right), ());
 427                    }
 428                } else {
 429                    if old_cursor.end() > edit.old.end {
 430                        let summary = self
 431                            .tab_snapshot
 432                            .text_summary_for_range(edit.old.end..old_cursor.end());
 433                        new_transforms.push_or_extend(Transform::isomorphic(summary));
 434                    }
 435                    old_cursor.next();
 436                    new_transforms.append(old_cursor.suffix(), ());
 437                }
 438            }
 439        }
 440
 441        let old_snapshot = mem::replace(
 442            self,
 443            WrapSnapshot {
 444                tab_snapshot: new_tab_snapshot,
 445                transforms: new_transforms,
 446                interpolated: true,
 447            },
 448        );
 449        self.check_invariants();
 450        old_snapshot.compute_edits(tab_edits, self)
 451    }
 452
 453    #[ztracing::instrument(skip_all)]
 454    async fn update(
 455        &mut self,
 456        new_tab_snapshot: TabSnapshot,
 457        tab_edits: &[TabEdit],
 458        wrap_width: Pixels,
 459        line_wrapper: &mut LineWrapper,
 460    ) -> WrapPatch {
 461        #[derive(Debug)]
 462        struct RowEdit {
 463            old_rows: Range<u32>,
 464            new_rows: Range<u32>,
 465        }
 466
 467        let mut tab_edits_iter = tab_edits.iter().peekable();
 468        let mut row_edits = Vec::with_capacity(tab_edits.len());
 469        while let Some(edit) = tab_edits_iter.next() {
 470            let mut row_edit = RowEdit {
 471                old_rows: edit.old.start.row()..edit.old.end.row() + 1,
 472                new_rows: edit.new.start.row()..edit.new.end.row() + 1,
 473            };
 474
 475            while let Some(next_edit) = tab_edits_iter.peek() {
 476                if next_edit.old.start.row() <= row_edit.old_rows.end {
 477                    row_edit.old_rows.end =
 478                        cmp::max(row_edit.old_rows.end, next_edit.old.end.row() + 1);
 479                    row_edit.new_rows.end =
 480                        cmp::max(row_edit.new_rows.end, next_edit.new.end.row() + 1);
 481                    tab_edits_iter.next();
 482                } else {
 483                    break;
 484                }
 485            }
 486
 487            row_edits.push(row_edit);
 488        }
 489
 490        let mut new_transforms;
 491        if row_edits.is_empty() {
 492            new_transforms = self.transforms.clone();
 493        } else {
 494            let mut row_edits = row_edits.into_iter().peekable();
 495            let mut old_cursor = self.transforms.cursor::<TabPoint>(());
 496
 497            new_transforms = old_cursor.slice(
 498                &TabPoint::new(row_edits.peek().unwrap().old_rows.start, 0),
 499                Bias::Right,
 500            );
 501
 502            while let Some(edit) = row_edits.next() {
 503                if edit.new_rows.start > new_transforms.summary().input.lines.row {
 504                    let summary = new_tab_snapshot.text_summary_for_range(
 505                        TabPoint(new_transforms.summary().input.lines)
 506                            ..TabPoint::new(edit.new_rows.start, 0),
 507                    );
 508                    new_transforms.push_or_extend(Transform::isomorphic(summary));
 509                }
 510
 511                let mut line = String::new();
 512                let mut line_fragments = Vec::new();
 513                let mut remaining = None;
 514                let mut chunks = new_tab_snapshot.chunks(
 515                    TabPoint::new(edit.new_rows.start, 0)..new_tab_snapshot.max_point(),
 516                    false,
 517                    Highlights::default(),
 518                );
 519                let mut edit_transforms = Vec::<Transform>::new();
 520                for (i, _) in (edit.new_rows.start..edit.new_rows.end).enumerate() {
 521                    while let Some(chunk) = remaining.take().or_else(|| chunks.next()) {
 522                        if let Some(ix) = chunk.text.find('\n') {
 523                            let (prefix, suffix) = chunk.text.split_at(ix + 1);
 524                            line_fragments.push(gpui::LineFragment::text(prefix));
 525                            line.push_str(prefix);
 526                            remaining = Some(Chunk {
 527                                text: suffix,
 528                                ..chunk
 529                            });
 530                            break;
 531                        } else {
 532                            if let Some(width) =
 533                                chunk.renderer.as_ref().and_then(|r| r.measured_width)
 534                            {
 535                                line_fragments
 536                                    .push(gpui::LineFragment::element(width, chunk.text.len()));
 537                            } else {
 538                                line_fragments.push(gpui::LineFragment::text(chunk.text));
 539                            }
 540                            line.push_str(chunk.text);
 541                        }
 542                    }
 543
 544                    if line.is_empty() {
 545                        break;
 546                    }
 547
 548                    let mut prev_boundary_ix = 0;
 549                    for boundary in line_wrapper.wrap_line(&line_fragments, wrap_width) {
 550                        let wrapped = &line[prev_boundary_ix..boundary.ix];
 551                        push_isomorphic(&mut edit_transforms, TextSummary::from(wrapped));
 552                        edit_transforms.push(Transform::wrap(boundary.next_indent));
 553                        prev_boundary_ix = boundary.ix;
 554                    }
 555
 556                    if prev_boundary_ix < line.len() {
 557                        push_isomorphic(
 558                            &mut edit_transforms,
 559                            TextSummary::from(&line[prev_boundary_ix..]),
 560                        );
 561                    }
 562
 563                    line.clear();
 564                    line_fragments.clear();
 565                    if i % WRAP_YIELD_ROW_INTERVAL == WRAP_YIELD_ROW_INTERVAL - 1 {
 566                        yield_now().await;
 567                    }
 568                }
 569
 570                let mut edit_transforms = edit_transforms.into_iter();
 571                if let Some(transform) = edit_transforms.next() {
 572                    new_transforms.push_or_extend(transform);
 573                }
 574                new_transforms.extend(edit_transforms, ());
 575
 576                old_cursor.seek_forward(&TabPoint::new(edit.old_rows.end, 0), Bias::Right);
 577                if let Some(next_edit) = row_edits.peek() {
 578                    if next_edit.old_rows.start > old_cursor.end().row() {
 579                        if old_cursor.end() > TabPoint::new(edit.old_rows.end, 0) {
 580                            let summary = self.tab_snapshot.text_summary_for_range(
 581                                TabPoint::new(edit.old_rows.end, 0)..old_cursor.end(),
 582                            );
 583                            new_transforms.push_or_extend(Transform::isomorphic(summary));
 584                        }
 585                        old_cursor.next();
 586                        new_transforms.append(
 587                            old_cursor
 588                                .slice(&TabPoint::new(next_edit.old_rows.start, 0), Bias::Right),
 589                            (),
 590                        );
 591                    }
 592                    yield_now().await;
 593                } else {
 594                    if old_cursor.end() > TabPoint::new(edit.old_rows.end, 0) {
 595                        let summary = self.tab_snapshot.text_summary_for_range(
 596                            TabPoint::new(edit.old_rows.end, 0)..old_cursor.end(),
 597                        );
 598                        new_transforms.push_or_extend(Transform::isomorphic(summary));
 599                    }
 600                    old_cursor.next();
 601                    new_transforms.append(old_cursor.suffix(), ());
 602                }
 603            }
 604        }
 605
 606        let old_snapshot = mem::replace(
 607            self,
 608            WrapSnapshot {
 609                tab_snapshot: new_tab_snapshot,
 610                transforms: new_transforms,
 611                interpolated: false,
 612            },
 613        );
 614        self.check_invariants();
 615        old_snapshot.compute_edits(tab_edits, self)
 616    }
 617
 618    #[ztracing::instrument(skip_all)]
 619    fn compute_edits(&self, tab_edits: &[TabEdit], new_snapshot: &WrapSnapshot) -> WrapPatch {
 620        let mut wrap_edits = Vec::with_capacity(tab_edits.len());
 621        let mut old_cursor = self.transforms.cursor::<TransformSummary>(());
 622        let mut new_cursor = new_snapshot.transforms.cursor::<TransformSummary>(());
 623        for mut tab_edit in tab_edits.iter().cloned() {
 624            tab_edit.old.start.0.column = 0;
 625            tab_edit.old.end.0 += Point::new(1, 0);
 626            tab_edit.new.start.0.column = 0;
 627            tab_edit.new.end.0 += Point::new(1, 0);
 628
 629            old_cursor.seek(&tab_edit.old.start, Bias::Right);
 630            let mut old_start = old_cursor.start().output.lines;
 631            old_start += tab_edit.old.start.0 - old_cursor.start().input.lines;
 632
 633            old_cursor.seek_forward(&tab_edit.old.end, Bias::Right);
 634            let mut old_end = old_cursor.start().output.lines;
 635            old_end += tab_edit.old.end.0 - old_cursor.start().input.lines;
 636
 637            new_cursor.seek(&tab_edit.new.start, Bias::Right);
 638            let mut new_start = new_cursor.start().output.lines;
 639            new_start += tab_edit.new.start.0 - new_cursor.start().input.lines;
 640
 641            new_cursor.seek_forward(&tab_edit.new.end, Bias::Right);
 642            let mut new_end = new_cursor.start().output.lines;
 643            new_end += tab_edit.new.end.0 - new_cursor.start().input.lines;
 644
 645            wrap_edits.push(WrapEdit {
 646                old: WrapRow(old_start.row)..WrapRow(old_end.row),
 647                new: WrapRow(new_start.row)..WrapRow(new_end.row),
 648            });
 649        }
 650
 651        wrap_edits = consolidate_wrap_edits(wrap_edits);
 652        Patch::new(wrap_edits)
 653    }
 654
 655    #[ztracing::instrument(skip_all)]
 656    pub(crate) fn chunks<'a>(
 657        &'a self,
 658        rows: Range<WrapRow>,
 659        language_aware: bool,
 660        highlights: Highlights<'a>,
 661    ) -> WrapChunks<'a> {
 662        let output_start = WrapPoint::new(rows.start, 0);
 663        let output_end = WrapPoint::new(rows.end, 0);
 664        let mut transforms = self
 665            .transforms
 666            .cursor::<Dimensions<WrapPoint, TabPoint>>(());
 667        transforms.seek(&output_start, Bias::Right);
 668        let mut input_start = TabPoint(transforms.start().1.0);
 669        if transforms.item().is_some_and(|t| t.is_isomorphic()) {
 670            input_start.0 += output_start.0 - transforms.start().0.0;
 671        }
 672        let input_end = self.to_tab_point(output_end);
 673        let max_point = self.tab_snapshot.max_point();
 674        let input_start = input_start.min(max_point);
 675        let input_end = input_end.min(max_point);
 676        WrapChunks {
 677            input_chunks: self.tab_snapshot.chunks(
 678                input_start..input_end,
 679                language_aware,
 680                highlights,
 681            ),
 682            input_chunk: Default::default(),
 683            output_position: output_start,
 684            max_output_row: rows.end,
 685            transforms,
 686            snapshot: self,
 687        }
 688    }
 689
 690    #[ztracing::instrument(skip_all)]
 691    pub fn max_point(&self) -> WrapPoint {
 692        WrapPoint(self.transforms.summary().output.lines)
 693    }
 694
 695    #[ztracing::instrument(skip_all)]
 696    pub fn line_len(&self, row: WrapRow) -> u32 {
 697        let (start, _, item) = self.transforms.find::<Dimensions<WrapPoint, TabPoint>, _>(
 698            (),
 699            &WrapPoint::new(row + WrapRow(1), 0),
 700            Bias::Left,
 701        );
 702        if item.is_some_and(|transform| transform.is_isomorphic()) {
 703            let overshoot = row - start.0.row();
 704            let tab_row = start.1.row() + overshoot.0;
 705            let tab_line_len = self.tab_snapshot.line_len(tab_row);
 706            if overshoot.0 == 0 {
 707                start.0.column() + (tab_line_len - start.1.column())
 708            } else {
 709                tab_line_len
 710            }
 711        } else {
 712            start.0.column()
 713        }
 714    }
 715
 716    #[ztracing::instrument(skip_all, fields(rows))]
 717    pub fn text_summary_for_range(&self, rows: Range<WrapRow>) -> TextSummary {
 718        let mut summary = TextSummary::default();
 719
 720        let start = WrapPoint::new(rows.start, 0);
 721        let end = WrapPoint::new(rows.end, 0);
 722
 723        let mut cursor = self
 724            .transforms
 725            .cursor::<Dimensions<WrapPoint, TabPoint>>(());
 726        cursor.seek(&start, Bias::Right);
 727        if let Some(transform) = cursor.item() {
 728            let start_in_transform = start.0 - cursor.start().0.0;
 729            let end_in_transform = cmp::min(end, cursor.end().0).0 - cursor.start().0.0;
 730            if transform.is_isomorphic() {
 731                let tab_start = TabPoint(cursor.start().1.0 + start_in_transform);
 732                let tab_end = TabPoint(cursor.start().1.0 + end_in_transform);
 733                summary += &self.tab_snapshot.text_summary_for_range(tab_start..tab_end);
 734            } else {
 735                debug_assert_eq!(start_in_transform.row, end_in_transform.row);
 736                let indent_len = end_in_transform.column - start_in_transform.column;
 737                summary += &TextSummary {
 738                    lines: Point::new(0, indent_len),
 739                    first_line_chars: indent_len,
 740                    last_line_chars: indent_len,
 741                    longest_row: 0,
 742                    longest_row_chars: indent_len,
 743                };
 744            }
 745
 746            cursor.next();
 747        }
 748
 749        if rows.end > cursor.start().0.row() {
 750            summary += &cursor
 751                .summary::<_, TransformSummary>(&WrapPoint::new(rows.end, 0), Bias::Right)
 752                .output;
 753
 754            if let Some(transform) = cursor.item() {
 755                let end_in_transform = end.0 - cursor.start().0.0;
 756                if transform.is_isomorphic() {
 757                    let char_start = cursor.start().1;
 758                    let char_end = TabPoint(char_start.0 + end_in_transform);
 759                    summary += &self
 760                        .tab_snapshot
 761                        .text_summary_for_range(char_start..char_end);
 762                } else {
 763                    debug_assert_eq!(end_in_transform, Point::new(1, 0));
 764                    summary += &TextSummary {
 765                        lines: Point::new(1, 0),
 766                        first_line_chars: 0,
 767                        last_line_chars: 0,
 768                        longest_row: 0,
 769                        longest_row_chars: 0,
 770                    };
 771                }
 772            }
 773        }
 774
 775        summary
 776    }
 777
 778    #[ztracing::instrument(skip_all)]
 779    pub fn soft_wrap_indent(&self, row: WrapRow) -> Option<u32> {
 780        let (.., item) = self.transforms.find::<WrapPoint, _>(
 781            (),
 782            &WrapPoint::new(row + WrapRow(1), 0),
 783            Bias::Right,
 784        );
 785        item.and_then(|transform| {
 786            if transform.is_isomorphic() {
 787                None
 788            } else {
 789                Some(transform.summary.output.lines.column)
 790            }
 791        })
 792    }
 793
 794    #[ztracing::instrument(skip_all)]
 795    pub fn longest_row(&self) -> u32 {
 796        self.transforms.summary().output.longest_row
 797    }
 798
 799    #[ztracing::instrument(skip_all)]
 800    pub fn row_infos(&self, start_row: WrapRow) -> WrapRows<'_> {
 801        let mut transforms = self
 802            .transforms
 803            .cursor::<Dimensions<WrapPoint, TabPoint>>(());
 804        transforms.seek(&WrapPoint::new(start_row, 0), Bias::Left);
 805        let mut input_row = transforms.start().1.row();
 806        if transforms.item().is_some_and(|t| t.is_isomorphic()) {
 807            input_row += (start_row - transforms.start().0.row()).0;
 808        }
 809        let soft_wrapped = transforms.item().is_some_and(|t| !t.is_isomorphic());
 810        let mut input_buffer_rows = self.tab_snapshot.rows(input_row);
 811        let input_buffer_row = input_buffer_rows.next().unwrap();
 812        WrapRows {
 813            transforms,
 814            input_buffer_row,
 815            input_buffer_rows,
 816            output_row: start_row,
 817            soft_wrapped,
 818            max_output_row: self.max_point().row(),
 819        }
 820    }
 821
 822    #[ztracing::instrument(skip_all)]
 823    pub fn to_tab_point(&self, point: WrapPoint) -> TabPoint {
 824        let (start, _, item) =
 825            self.transforms
 826                .find::<Dimensions<WrapPoint, TabPoint>, _>((), &point, Bias::Right);
 827        let mut tab_point = start.1.0;
 828        if item.is_some_and(|t| t.is_isomorphic()) {
 829            tab_point += point.0 - start.0.0;
 830        }
 831        TabPoint(tab_point)
 832    }
 833
 834    #[ztracing::instrument(skip_all)]
 835    pub fn to_point(&self, point: WrapPoint, bias: Bias) -> Point {
 836        self.tab_snapshot
 837            .tab_point_to_point(self.to_tab_point(point), bias)
 838    }
 839
 840    #[ztracing::instrument(skip_all)]
 841    pub fn make_wrap_point(&self, point: Point, bias: Bias) -> WrapPoint {
 842        self.tab_point_to_wrap_point(self.tab_snapshot.point_to_tab_point(point, bias))
 843    }
 844
 845    #[ztracing::instrument(skip_all)]
 846    pub fn tab_point_to_wrap_point(&self, point: TabPoint) -> WrapPoint {
 847        let (start, ..) =
 848            self.transforms
 849                .find::<Dimensions<TabPoint, WrapPoint>, _>((), &point, Bias::Right);
 850        WrapPoint(start.1.0 + (point.0 - start.0.0))
 851    }
 852
 853    #[ztracing::instrument(skip_all)]
 854    pub fn wrap_point_cursor(&self) -> WrapPointCursor<'_> {
 855        WrapPointCursor {
 856            cursor: self
 857                .transforms
 858                .cursor::<Dimensions<TabPoint, WrapPoint>>(()),
 859        }
 860    }
 861
 862    #[ztracing::instrument(skip_all)]
 863    pub fn clip_point(&self, mut point: WrapPoint, bias: Bias) -> WrapPoint {
 864        if bias == Bias::Left {
 865            let (start, _, item) = self
 866                .transforms
 867                .find::<WrapPoint, _>((), &point, Bias::Right);
 868            if item.is_some_and(|t| !t.is_isomorphic()) {
 869                point = start;
 870                *point.column_mut() -= 1;
 871            }
 872        }
 873
 874        self.tab_point_to_wrap_point(self.tab_snapshot.clip_point(self.to_tab_point(point), bias))
 875    }
 876
 877    /// Try to find a TabRow start that is also a WrapRow start
 878    /// Every TabRow start is a WrapRow start
 879    #[ztracing::instrument(skip_all, fields(point=?point))]
 880    pub fn prev_row_boundary(&self, point: WrapPoint) -> WrapRow {
 881        if self.transforms.is_empty() {
 882            return WrapRow(0);
 883        }
 884
 885        let point = WrapPoint::new(point.row(), 0);
 886
 887        let mut cursor = self
 888            .transforms
 889            .cursor::<Dimensions<WrapPoint, TabPoint>>(());
 890
 891        cursor.seek(&point, Bias::Right);
 892        if cursor.item().is_none() {
 893            cursor.prev();
 894        }
 895
 896        //                          real newline     fake          fake
 897        // text:      helloworldasldlfjasd\njdlasfalsk\naskdjfasdkfj\n
 898        // dimensions v       v           v            v            v
 899        // transforms |-------|-----NW----|-----W------|-----W------|
 900        // cursor    ^        ^^^^^^^^^^^^^                          ^
 901        //                               (^)           ^^^^^^^^^^^^^^
 902        // point:                                            ^
 903        // point(col_zero):                           (^)
 904
 905        while let Some(transform) = cursor.item() {
 906            if transform.is_isomorphic() {
 907                // this transform only has real linefeeds
 908                let tab_summary = &transform.summary.input;
 909                // is the wrap just before the end of the transform a tab row?
 910                // thats only if this transform has at least one newline
 911                //
 912                // "this wrap row is a tab row" <=> self.to_tab_point(WrapPoint::new(wrap_row, 0)).column() == 0
 913
 914                // Note on comparison:
 915                // We have code that relies on this to be row > 1
 916                // It should work with row >= 1 but it does not :(
 917                //
 918                // That means that if every line is wrapped we walk back all the
 919                // way to the start. Which invalidates the entire state triggering
 920                // a full re-render.
 921                if tab_summary.lines.row > 1 {
 922                    let wrap_point_at_end = cursor.end().0.row();
 923                    return cmp::min(wrap_point_at_end - RowDelta(1), point.row());
 924                } else if cursor.start().1.column() == 0 {
 925                    return cmp::min(cursor.end().0.row(), point.row());
 926                }
 927            }
 928
 929            cursor.prev();
 930        }
 931
 932        WrapRow(0)
 933    }
 934
 935    #[ztracing::instrument(skip_all)]
 936    pub fn next_row_boundary(&self, mut point: WrapPoint) -> Option<WrapRow> {
 937        point.0 += Point::new(1, 0);
 938
 939        let mut cursor = self
 940            .transforms
 941            .cursor::<Dimensions<WrapPoint, TabPoint>>(());
 942        cursor.seek(&point, Bias::Right);
 943        while let Some(transform) = cursor.item() {
 944            if transform.is_isomorphic() && cursor.start().1.column() == 0 {
 945                return Some(cmp::max(cursor.start().0.row(), point.row()));
 946            } else {
 947                cursor.next();
 948            }
 949        }
 950
 951        None
 952    }
 953
 954    #[cfg(test)]
 955    pub fn text(&self) -> String {
 956        self.text_chunks(WrapRow(0)).collect()
 957    }
 958
 959    #[cfg(test)]
 960    pub fn text_chunks(&self, wrap_row: WrapRow) -> impl Iterator<Item = &str> {
 961        self.chunks(
 962            wrap_row..self.max_point().row() + WrapRow(1),
 963            false,
 964            Highlights::default(),
 965        )
 966        .map(|h| h.text)
 967    }
 968
 969    #[ztracing::instrument(skip_all)]
 970    fn check_invariants(&self) {
 971        #[cfg(test)]
 972        {
 973            assert_eq!(
 974                TabPoint::from(self.transforms.summary().input.lines),
 975                self.tab_snapshot.max_point()
 976            );
 977
 978            {
 979                let mut transforms = self.transforms.cursor::<()>(()).peekable();
 980                while let Some(transform) = transforms.next() {
 981                    if let Some(next_transform) = transforms.peek() {
 982                        assert!(transform.is_isomorphic() != next_transform.is_isomorphic());
 983                    }
 984                }
 985            }
 986
 987            let text = language::Rope::from(self.text().as_str());
 988            let mut input_buffer_rows = self.tab_snapshot.rows(0);
 989            let mut expected_buffer_rows = Vec::new();
 990            let mut prev_tab_row = 0;
 991            for display_row in 0..=self.max_point().row().0 {
 992                let display_row = WrapRow(display_row);
 993                let tab_point = self.to_tab_point(WrapPoint::new(display_row, 0));
 994                if tab_point.row() == prev_tab_row && display_row != WrapRow(0) {
 995                    expected_buffer_rows.push(None);
 996                } else {
 997                    expected_buffer_rows.push(input_buffer_rows.next().unwrap().buffer_row);
 998                }
 999
1000                prev_tab_row = tab_point.row();
1001                assert_eq!(self.line_len(display_row), text.line_len(display_row.0));
1002            }
1003
1004            for start_display_row in 0..expected_buffer_rows.len() {
1005                assert_eq!(
1006                    self.row_infos(WrapRow(start_display_row as u32))
1007                        .map(|row_info| row_info.buffer_row)
1008                        .collect::<Vec<_>>(),
1009                    &expected_buffer_rows[start_display_row..],
1010                    "invalid buffer_rows({}..)",
1011                    start_display_row
1012                );
1013            }
1014        }
1015    }
1016}
1017
1018pub struct WrapPointCursor<'transforms> {
1019    cursor: Cursor<'transforms, 'static, Transform, Dimensions<TabPoint, WrapPoint>>,
1020}
1021
1022impl WrapPointCursor<'_> {
1023    #[ztracing::instrument(skip_all)]
1024    pub fn map(&mut self, point: TabPoint) -> WrapPoint {
1025        let cursor = &mut self.cursor;
1026        if cursor.did_seek() {
1027            cursor.seek_forward(&point, Bias::Right);
1028        } else {
1029            cursor.seek(&point, Bias::Right);
1030        }
1031        WrapPoint(cursor.start().1.0 + (point.0 - cursor.start().0.0))
1032    }
1033}
1034
1035impl WrapChunks<'_> {
1036    #[ztracing::instrument(skip_all)]
1037    pub(crate) fn seek(&mut self, rows: Range<WrapRow>) {
1038        let output_start = WrapPoint::new(rows.start, 0);
1039        let output_end = WrapPoint::new(rows.end, 0);
1040        self.transforms.seek(&output_start, Bias::Right);
1041        let mut input_start = TabPoint(self.transforms.start().1.0);
1042        if self.transforms.item().is_some_and(|t| t.is_isomorphic()) {
1043            input_start.0 += output_start.0 - self.transforms.start().0.0;
1044        }
1045        let input_end = self.snapshot.to_tab_point(output_end);
1046        let max_point = self.snapshot.tab_snapshot.max_point();
1047        let input_start = input_start.min(max_point);
1048        let input_end = input_end.min(max_point);
1049        self.input_chunks.seek(input_start..input_end);
1050        self.input_chunk = Chunk::default();
1051        self.output_position = output_start;
1052        self.max_output_row = rows.end;
1053    }
1054}
1055
1056impl<'a> Iterator for WrapChunks<'a> {
1057    type Item = Chunk<'a>;
1058
1059    #[ztracing::instrument(skip_all)]
1060    fn next(&mut self) -> Option<Self::Item> {
1061        if self.output_position.row() >= self.max_output_row {
1062            return None;
1063        }
1064
1065        let transform = self.transforms.item()?;
1066        if let Some(display_text) = transform.display_text {
1067            let mut start_ix = 0;
1068            let mut end_ix = display_text.len();
1069            let mut summary = transform.summary.output.lines;
1070
1071            if self.output_position > self.transforms.start().0 {
1072                // Exclude newline starting prior to the desired row.
1073                start_ix = 1;
1074                summary.row = 0;
1075            } else if self.output_position.row() + WrapRow(1) >= self.max_output_row {
1076                // Exclude soft indentation ending after the desired row.
1077                end_ix = 1;
1078                summary.column = 0;
1079            }
1080
1081            self.output_position.0 += summary;
1082            self.transforms.next();
1083            return Some(Chunk {
1084                text: &display_text[start_ix..end_ix],
1085                ..Default::default()
1086            });
1087        }
1088
1089        if self.input_chunk.text.is_empty() {
1090            self.input_chunk = self.input_chunks.next()?;
1091        }
1092
1093        let mut input_len = 0;
1094        let transform_end = self.transforms.end().0;
1095        for c in self.input_chunk.text.chars() {
1096            let char_len = c.len_utf8();
1097            input_len += char_len;
1098            if c == '\n' {
1099                *self.output_position.row_mut() += 1;
1100                *self.output_position.column_mut() = 0;
1101            } else {
1102                *self.output_position.column_mut() += char_len as u32;
1103            }
1104
1105            if self.output_position >= transform_end {
1106                self.transforms.next();
1107                break;
1108            }
1109        }
1110
1111        let (prefix, suffix) = self.input_chunk.text.split_at(input_len);
1112
1113        let mask = 1u128.unbounded_shl(input_len as u32).wrapping_sub(1);
1114        let chars = self.input_chunk.chars & mask;
1115        let tabs = self.input_chunk.tabs & mask;
1116        let newlines = self.input_chunk.newlines & mask;
1117        self.input_chunk.tabs = self.input_chunk.tabs.unbounded_shr(input_len as u32);
1118        self.input_chunk.chars = self.input_chunk.chars.unbounded_shr(input_len as u32);
1119        self.input_chunk.newlines = self.input_chunk.newlines.unbounded_shr(input_len as u32);
1120
1121        self.input_chunk.text = suffix;
1122        Some(Chunk {
1123            text: prefix,
1124            chars,
1125            tabs,
1126            newlines,
1127            ..self.input_chunk.clone()
1128        })
1129    }
1130}
1131
1132impl Iterator for WrapRows<'_> {
1133    type Item = RowInfo;
1134
1135    #[ztracing::instrument(skip_all)]
1136    fn next(&mut self) -> Option<Self::Item> {
1137        if self.output_row > self.max_output_row {
1138            return None;
1139        }
1140
1141        let buffer_row = self.input_buffer_row;
1142        let soft_wrapped = self.soft_wrapped;
1143        let diff_status = self.input_buffer_row.diff_status;
1144
1145        self.output_row += WrapRow(1);
1146        self.transforms
1147            .seek_forward(&WrapPoint::new(self.output_row, 0), Bias::Left);
1148        if self.transforms.item().is_some_and(|t| t.is_isomorphic()) {
1149            self.input_buffer_row = self.input_buffer_rows.next().unwrap();
1150            self.soft_wrapped = false;
1151        } else {
1152            self.soft_wrapped = true;
1153        }
1154
1155        Some(if soft_wrapped {
1156            RowInfo {
1157                buffer_id: None,
1158                buffer_row: None,
1159                multibuffer_row: None,
1160                diff_status,
1161                expand_info: None,
1162                wrapped_buffer_row: buffer_row.buffer_row,
1163            }
1164        } else {
1165            buffer_row
1166        })
1167    }
1168}
1169
1170impl Transform {
1171    #[ztracing::instrument(skip_all)]
1172    fn isomorphic(summary: TextSummary) -> Self {
1173        #[cfg(test)]
1174        assert!(!summary.lines.is_zero());
1175
1176        Self {
1177            summary: TransformSummary {
1178                input: summary.clone(),
1179                output: summary,
1180            },
1181            display_text: None,
1182        }
1183    }
1184
1185    #[ztracing::instrument(skip_all)]
1186    fn wrap(indent: u32) -> Self {
1187        static WRAP_TEXT: LazyLock<String> = LazyLock::new(|| {
1188            let mut wrap_text = String::new();
1189            wrap_text.push('\n');
1190            wrap_text.extend((0..LineWrapper::MAX_INDENT as usize).map(|_| ' '));
1191            wrap_text
1192        });
1193
1194        Self {
1195            summary: TransformSummary {
1196                input: TextSummary::default(),
1197                output: TextSummary {
1198                    lines: Point::new(1, indent),
1199                    first_line_chars: 0,
1200                    last_line_chars: indent,
1201                    longest_row: 1,
1202                    longest_row_chars: indent,
1203                },
1204            },
1205            display_text: Some(&WRAP_TEXT[..1 + indent as usize]),
1206        }
1207    }
1208
1209    fn is_isomorphic(&self) -> bool {
1210        self.display_text.is_none()
1211    }
1212}
1213
1214impl sum_tree::Item for Transform {
1215    type Summary = TransformSummary;
1216
1217    fn summary(&self, _cx: ()) -> Self::Summary {
1218        self.summary.clone()
1219    }
1220}
1221
1222fn push_isomorphic(transforms: &mut Vec<Transform>, summary: TextSummary) {
1223    if let Some(last_transform) = transforms.last_mut()
1224        && last_transform.is_isomorphic()
1225    {
1226        last_transform.summary.input += &summary;
1227        last_transform.summary.output += &summary;
1228        return;
1229    }
1230    transforms.push(Transform::isomorphic(summary));
1231}
1232
1233trait SumTreeExt {
1234    fn push_or_extend(&mut self, transform: Transform);
1235}
1236
1237impl SumTreeExt for SumTree<Transform> {
1238    #[ztracing::instrument(skip_all)]
1239    fn push_or_extend(&mut self, transform: Transform) {
1240        let mut transform = Some(transform);
1241        self.update_last(
1242            |last_transform| {
1243                if last_transform.is_isomorphic() && transform.as_ref().unwrap().is_isomorphic() {
1244                    let transform = transform.take().unwrap();
1245                    last_transform.summary.input += &transform.summary.input;
1246                    last_transform.summary.output += &transform.summary.output;
1247                }
1248            },
1249            (),
1250        );
1251
1252        if let Some(transform) = transform {
1253            self.push(transform, ());
1254        }
1255    }
1256}
1257
1258impl WrapPoint {
1259    pub fn new(row: WrapRow, column: u32) -> Self {
1260        Self(Point::new(row.0, column))
1261    }
1262
1263    pub fn row(self) -> WrapRow {
1264        WrapRow(self.0.row)
1265    }
1266
1267    pub fn row_mut(&mut self) -> &mut u32 {
1268        &mut self.0.row
1269    }
1270
1271    pub fn column(self) -> u32 {
1272        self.0.column
1273    }
1274
1275    pub fn column_mut(&mut self) -> &mut u32 {
1276        &mut self.0.column
1277    }
1278}
1279
1280impl sum_tree::ContextLessSummary for TransformSummary {
1281    fn zero() -> Self {
1282        Default::default()
1283    }
1284
1285    fn add_summary(&mut self, other: &Self) {
1286        self.input += &other.input;
1287        self.output += &other.output;
1288    }
1289}
1290
1291impl<'a> sum_tree::Dimension<'a, TransformSummary> for TabPoint {
1292    fn zero(_cx: ()) -> Self {
1293        Default::default()
1294    }
1295
1296    fn add_summary(&mut self, summary: &'a TransformSummary, _: ()) {
1297        self.0 += summary.input.lines;
1298    }
1299}
1300
1301impl sum_tree::SeekTarget<'_, TransformSummary, TransformSummary> for TabPoint {
1302    #[ztracing::instrument(skip_all)]
1303    fn cmp(&self, cursor_location: &TransformSummary, _: ()) -> std::cmp::Ordering {
1304        Ord::cmp(&self.0, &cursor_location.input.lines)
1305    }
1306}
1307
1308impl<'a> sum_tree::Dimension<'a, TransformSummary> for WrapPoint {
1309    fn zero(_cx: ()) -> Self {
1310        Default::default()
1311    }
1312
1313    fn add_summary(&mut self, summary: &'a TransformSummary, _: ()) {
1314        self.0 += summary.output.lines;
1315    }
1316}
1317
1318fn consolidate_wrap_edits(edits: Vec<WrapEdit>) -> Vec<WrapEdit> {
1319    let _old_alloc_ptr = edits.as_ptr();
1320    let mut wrap_edits = edits.into_iter();
1321
1322    if let Some(mut first_edit) = wrap_edits.next() {
1323        // This code relies on reusing allocations from the Vec<_> - at the time of writing .flatten() prevents them.
1324        #[allow(clippy::filter_map_identity)]
1325        let mut v: Vec<_> = wrap_edits
1326            .scan(&mut first_edit, |prev_edit, edit| {
1327                if prev_edit.old.end >= edit.old.start {
1328                    prev_edit.old.end = edit.old.end;
1329                    prev_edit.new.end = edit.new.end;
1330                    Some(None) // Skip this edit, it's merged
1331                } else {
1332                    let prev = std::mem::replace(*prev_edit, edit);
1333                    Some(Some(prev)) // Yield the previous edit
1334                }
1335            })
1336            .filter_map(|x| x)
1337            .collect();
1338        v.push(first_edit.clone());
1339        debug_assert_eq!(v.as_ptr(), _old_alloc_ptr, "Wrap edits were reallocated");
1340        v
1341    } else {
1342        vec![]
1343    }
1344}
1345
1346#[cfg(test)]
1347mod tests {
1348    use super::*;
1349    use crate::{
1350        MultiBuffer,
1351        display_map::{fold_map::FoldMap, inlay_map::InlayMap, tab_map::TabMap},
1352        test::test_font,
1353    };
1354    use gpui::{LineFragment, px, test::observe};
1355    use rand::prelude::*;
1356    use settings::SettingsStore;
1357    use smol::stream::StreamExt;
1358    use std::{cmp, env, num::NonZeroU32};
1359    use text::Rope;
1360    use theme::LoadThemes;
1361
1362    #[gpui::test]
1363    async fn test_prev_row_boundary(cx: &mut gpui::TestAppContext) {
1364        init_test(cx);
1365
1366        fn test_wrap_snapshot(
1367            text: &str,
1368            soft_wrap_every: usize, // font size multiple
1369            cx: &mut gpui::TestAppContext,
1370        ) -> WrapSnapshot {
1371            let text_system = cx.read(|cx| cx.text_system().clone());
1372            let tab_size = 4.try_into().unwrap();
1373            let font = test_font();
1374            let _font_id = text_system.resolve_font(&font);
1375            let font_size = px(14.0);
1376            // this is very much an estimate to try and get the wrapping to
1377            // occur at `soft_wrap_every` we check that it pans out for every test case
1378            let soft_wrapping = Some(font_size * soft_wrap_every * 0.6);
1379
1380            let buffer = cx.new(|cx| language::Buffer::local(text, cx));
1381            let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
1382            let buffer_snapshot = buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx));
1383            let (_inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot);
1384            let (_fold_map, fold_snapshot) = FoldMap::new(inlay_snapshot);
1385            let (mut tab_map, _) = TabMap::new(fold_snapshot, tab_size);
1386            let tabs_snapshot = tab_map.set_max_expansion_column(32);
1387            let (_wrap_map, wrap_snapshot) =
1388                cx.update(|cx| WrapMap::new(tabs_snapshot, font, font_size, soft_wrapping, cx));
1389
1390            wrap_snapshot
1391        }
1392
1393        // These two should pass but dont, see the comparison note in
1394        // prev_row_boundary about why.
1395        //
1396        // //                                      0123  4567  wrap_rows
1397        // let wrap_snapshot = test_wrap_snapshot("1234\n5678", 1, cx);
1398        // assert_eq!(wrap_snapshot.text(), "1\n2\n3\n4\n5\n6\n7\n8");
1399        // let row = wrap_snapshot.prev_row_boundary(wrap_snapshot.max_point());
1400        // assert_eq!(row.0, 3);
1401
1402        // //                                      012  345  678  wrap_rows
1403        // let wrap_snapshot = test_wrap_snapshot("123\n456\n789", 1, cx);
1404        // assert_eq!(wrap_snapshot.text(), "1\n2\n3\n4\n5\n6\n7\n8\n9");
1405        // let row = wrap_snapshot.prev_row_boundary(wrap_snapshot.max_point());
1406        // assert_eq!(row.0, 5);
1407
1408        //                                      012345678  wrap_rows
1409        let wrap_snapshot = test_wrap_snapshot("123456789", 1, cx);
1410        assert_eq!(wrap_snapshot.text(), "1\n2\n3\n4\n5\n6\n7\n8\n9");
1411        let row = wrap_snapshot.prev_row_boundary(wrap_snapshot.max_point());
1412        assert_eq!(row.0, 0);
1413
1414        //                                      111  2222    44  wrap_rows
1415        let wrap_snapshot = test_wrap_snapshot("123\n4567\n\n89", 4, cx);
1416        assert_eq!(wrap_snapshot.text(), "123\n4567\n\n89");
1417        let row = wrap_snapshot.prev_row_boundary(wrap_snapshot.max_point());
1418        assert_eq!(row.0, 2);
1419
1420        //                                      11  2223   wrap_rows
1421        let wrap_snapshot = test_wrap_snapshot("12\n3456\n\n", 3, cx);
1422        assert_eq!(wrap_snapshot.text(), "12\n345\n6\n\n");
1423        let row = wrap_snapshot.prev_row_boundary(wrap_snapshot.max_point());
1424        assert_eq!(row.0, 3);
1425    }
1426
1427    #[gpui::test(iterations = 100)]
1428    async fn test_random_wraps(cx: &mut gpui::TestAppContext, mut rng: StdRng) {
1429        // todo this test is flaky
1430        init_test(cx);
1431
1432        cx.background_executor.set_block_on_ticks(0..=50);
1433        let operations = env::var("OPERATIONS")
1434            .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
1435            .unwrap_or(10);
1436
1437        let text_system = cx.read(|cx| cx.text_system().clone());
1438        let mut wrap_width = if rng.random_bool(0.1) {
1439            None
1440        } else {
1441            Some(px(rng.random_range(0.0..=1000.0)))
1442        };
1443        let tab_size = NonZeroU32::new(rng.random_range(1..=4)).unwrap();
1444
1445        let font = test_font();
1446        let _font_id = text_system.resolve_font(&font);
1447        let font_size = px(14.0);
1448
1449        log::info!("Tab size: {}", tab_size);
1450        log::info!("Wrap width: {:?}", wrap_width);
1451
1452        let buffer = cx.update(|cx| {
1453            if rng.random() {
1454                MultiBuffer::build_random(&mut rng, cx)
1455            } else {
1456                let len = rng.random_range(0..10);
1457                let text = util::RandomCharIter::new(&mut rng)
1458                    .take(len)
1459                    .collect::<String>();
1460                MultiBuffer::build_simple(&text, cx)
1461            }
1462        });
1463        let mut buffer_snapshot = buffer.read_with(cx, |buffer, cx| buffer.snapshot(cx));
1464        log::info!("Buffer text: {:?}", buffer_snapshot.text());
1465        let (mut inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
1466        log::info!("InlayMap text: {:?}", inlay_snapshot.text());
1467        let (mut fold_map, fold_snapshot) = FoldMap::new(inlay_snapshot.clone());
1468        log::info!("FoldMap text: {:?}", fold_snapshot.text());
1469        let (mut tab_map, _) = TabMap::new(fold_snapshot.clone(), tab_size);
1470        let tabs_snapshot = tab_map.set_max_expansion_column(32);
1471        log::info!("TabMap text: {:?}", tabs_snapshot.text());
1472
1473        let mut line_wrapper = text_system.line_wrapper(font.clone(), font_size);
1474        let expected_text = wrap_text(&tabs_snapshot, wrap_width, &mut line_wrapper);
1475
1476        let (wrap_map, _) =
1477            cx.update(|cx| WrapMap::new(tabs_snapshot.clone(), font, font_size, wrap_width, cx));
1478        let mut notifications = observe(&wrap_map, cx);
1479
1480        if wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1481            notifications.next().await.unwrap();
1482        }
1483
1484        let (initial_snapshot, _) = wrap_map.update(cx, |map, cx| {
1485            assert!(!map.is_rewrapping());
1486            map.sync(tabs_snapshot.clone(), Vec::new(), cx)
1487        });
1488
1489        let actual_text = initial_snapshot.text();
1490        assert_eq!(
1491            actual_text,
1492            expected_text,
1493            "unwrapped text is: {:?}",
1494            tabs_snapshot.text()
1495        );
1496        log::info!("Wrapped text: {:?}", actual_text);
1497
1498        let mut next_inlay_id = 0;
1499        let mut edits = Vec::new();
1500        for _i in 0..operations {
1501            log::info!("{} ==============================================", _i);
1502
1503            let mut buffer_edits = Vec::new();
1504            match rng.random_range(0..=100) {
1505                0..=19 => {
1506                    wrap_width = if rng.random_bool(0.2) {
1507                        None
1508                    } else {
1509                        Some(px(rng.random_range(0.0..=1000.0)))
1510                    };
1511                    log::info!("Setting wrap width to {:?}", wrap_width);
1512                    wrap_map.update(cx, |map, cx| map.set_wrap_width(wrap_width, cx));
1513                }
1514                20..=39 => {
1515                    for (fold_snapshot, fold_edits) in fold_map.randomly_mutate(&mut rng) {
1516                        let (tabs_snapshot, tab_edits) =
1517                            tab_map.sync(fold_snapshot, fold_edits, tab_size);
1518                        let (mut snapshot, wrap_edits) =
1519                            wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot, tab_edits, cx));
1520                        snapshot.check_invariants();
1521                        snapshot.verify_chunks(&mut rng);
1522                        edits.push((snapshot, wrap_edits));
1523                    }
1524                }
1525                40..=59 => {
1526                    let (inlay_snapshot, inlay_edits) =
1527                        inlay_map.randomly_mutate(&mut next_inlay_id, &mut rng);
1528                    let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1529                    let (tabs_snapshot, tab_edits) =
1530                        tab_map.sync(fold_snapshot, fold_edits, tab_size);
1531                    let (mut snapshot, wrap_edits) =
1532                        wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot, tab_edits, cx));
1533                    snapshot.check_invariants();
1534                    snapshot.verify_chunks(&mut rng);
1535                    edits.push((snapshot, wrap_edits));
1536                }
1537                _ => {
1538                    buffer.update(cx, |buffer, cx| {
1539                        let subscription = buffer.subscribe();
1540                        let edit_count = rng.random_range(1..=5);
1541                        buffer.randomly_mutate(&mut rng, edit_count, cx);
1542                        buffer_snapshot = buffer.snapshot(cx);
1543                        buffer_edits.extend(subscription.consume());
1544                    });
1545                }
1546            }
1547
1548            log::info!("Buffer text: {:?}", buffer_snapshot.text());
1549            let (inlay_snapshot, inlay_edits) =
1550                inlay_map.sync(buffer_snapshot.clone(), buffer_edits);
1551            log::info!("InlayMap text: {:?}", inlay_snapshot.text());
1552            let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1553            log::info!("FoldMap text: {:?}", fold_snapshot.text());
1554            let (tabs_snapshot, tab_edits) = tab_map.sync(fold_snapshot, fold_edits, tab_size);
1555            log::info!("TabMap text: {:?}", tabs_snapshot.text());
1556
1557            let expected_text = wrap_text(&tabs_snapshot, wrap_width, &mut line_wrapper);
1558            let (mut snapshot, wrap_edits) =
1559                wrap_map.update(cx, |map, cx| map.sync(tabs_snapshot.clone(), tab_edits, cx));
1560            snapshot.check_invariants();
1561            snapshot.verify_chunks(&mut rng);
1562            edits.push((snapshot, wrap_edits));
1563
1564            if wrap_map.read_with(cx, |map, _| map.is_rewrapping()) && rng.random_bool(0.4) {
1565                log::info!("Waiting for wrapping to finish");
1566                while wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1567                    notifications.next().await.unwrap();
1568                }
1569                wrap_map.read_with(cx, |map, _| assert!(map.pending_edits.is_empty()));
1570            }
1571
1572            if !wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1573                let (mut wrapped_snapshot, wrap_edits) = wrap_map.update(cx, |map, cx| {
1574                    map.sync(tabs_snapshot.clone(), Vec::new(), cx)
1575                });
1576                let actual_text = wrapped_snapshot.text();
1577                let actual_longest_row = wrapped_snapshot.longest_row();
1578                log::info!("Wrapping finished: {:?}", actual_text);
1579                wrapped_snapshot.check_invariants();
1580                wrapped_snapshot.verify_chunks(&mut rng);
1581                edits.push((wrapped_snapshot.clone(), wrap_edits));
1582                assert_eq!(
1583                    actual_text,
1584                    expected_text,
1585                    "unwrapped text is: {:?}",
1586                    tabs_snapshot.text()
1587                );
1588
1589                let mut summary = TextSummary::default();
1590                for (ix, item) in wrapped_snapshot
1591                    .transforms
1592                    .items(())
1593                    .into_iter()
1594                    .enumerate()
1595                {
1596                    summary += &item.summary.output;
1597                    log::info!("{} summary: {:?}", ix, item.summary.output,);
1598                }
1599
1600                if tab_size.get() == 1
1601                    || !wrapped_snapshot
1602                        .tab_snapshot
1603                        .fold_snapshot
1604                        .text()
1605                        .contains('\t')
1606                {
1607                    let mut expected_longest_rows = Vec::new();
1608                    let mut longest_line_len = -1;
1609                    for (row, line) in expected_text.split('\n').enumerate() {
1610                        let line_char_count = line.chars().count() as isize;
1611                        if line_char_count > longest_line_len {
1612                            expected_longest_rows.clear();
1613                            longest_line_len = line_char_count;
1614                        }
1615                        if line_char_count >= longest_line_len {
1616                            expected_longest_rows.push(row as u32);
1617                        }
1618                    }
1619
1620                    assert!(
1621                        expected_longest_rows.contains(&actual_longest_row),
1622                        "incorrect longest row {}. expected {:?} with length {}",
1623                        actual_longest_row,
1624                        expected_longest_rows,
1625                        longest_line_len,
1626                    )
1627                }
1628            }
1629        }
1630
1631        let mut initial_text = Rope::from(initial_snapshot.text().as_str());
1632        for (snapshot, patch) in edits {
1633            let snapshot_text = Rope::from(snapshot.text().as_str());
1634            for edit in &patch {
1635                let old_start = initial_text.point_to_offset(Point::new(edit.new.start.0, 0));
1636                let old_end = initial_text.point_to_offset(cmp::min(
1637                    Point::new(edit.new.start.0 + (edit.old.end - edit.old.start).0, 0),
1638                    initial_text.max_point(),
1639                ));
1640                let new_start = snapshot_text.point_to_offset(Point::new(edit.new.start.0, 0));
1641                let new_end = snapshot_text.point_to_offset(cmp::min(
1642                    Point::new(edit.new.end.0, 0),
1643                    snapshot_text.max_point(),
1644                ));
1645                let new_text = snapshot_text
1646                    .chunks_in_range(new_start..new_end)
1647                    .collect::<String>();
1648
1649                initial_text.replace(old_start..old_end, &new_text);
1650            }
1651            assert_eq!(initial_text.to_string(), snapshot_text.to_string());
1652        }
1653
1654        if wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1655            log::info!("Waiting for wrapping to finish");
1656            while wrap_map.read_with(cx, |map, _| map.is_rewrapping()) {
1657                notifications.next().await.unwrap();
1658            }
1659        }
1660        wrap_map.read_with(cx, |map, _| assert!(map.pending_edits.is_empty()));
1661    }
1662
1663    fn init_test(cx: &mut gpui::TestAppContext) {
1664        cx.update(|cx| {
1665            let settings = SettingsStore::test(cx);
1666            cx.set_global(settings);
1667            theme::init(LoadThemes::JustBase, cx);
1668        });
1669    }
1670
1671    fn wrap_text(
1672        tab_snapshot: &TabSnapshot,
1673        wrap_width: Option<Pixels>,
1674        line_wrapper: &mut LineWrapper,
1675    ) -> String {
1676        if let Some(wrap_width) = wrap_width {
1677            let mut wrapped_text = String::new();
1678            for (row, line) in tab_snapshot.text().split('\n').enumerate() {
1679                if row > 0 {
1680                    wrapped_text.push('\n');
1681                }
1682
1683                let mut prev_ix = 0;
1684                for boundary in line_wrapper.wrap_line(&[LineFragment::text(line)], wrap_width) {
1685                    wrapped_text.push_str(&line[prev_ix..boundary.ix]);
1686                    wrapped_text.push('\n');
1687                    wrapped_text.push_str(&" ".repeat(boundary.next_indent as usize));
1688                    prev_ix = boundary.ix;
1689                }
1690                wrapped_text.push_str(&line[prev_ix..]);
1691            }
1692
1693            wrapped_text
1694        } else {
1695            tab_snapshot.text()
1696        }
1697    }
1698
1699    impl WrapSnapshot {
1700        fn verify_chunks(&mut self, rng: &mut impl Rng) {
1701            for _ in 0..5 {
1702                let mut end_row = rng.random_range(0..=self.max_point().row().0);
1703                let start_row = rng.random_range(0..=end_row);
1704                end_row += 1;
1705
1706                let mut expected_text = self.text_chunks(WrapRow(start_row)).collect::<String>();
1707                if expected_text.ends_with('\n') {
1708                    expected_text.push('\n');
1709                }
1710                let mut expected_text = expected_text
1711                    .lines()
1712                    .take((end_row - start_row) as usize)
1713                    .collect::<Vec<_>>()
1714                    .join("\n");
1715                if end_row <= self.max_point().row().0 {
1716                    expected_text.push('\n');
1717                }
1718
1719                let actual_text = self
1720                    .chunks(
1721                        WrapRow(start_row)..WrapRow(end_row),
1722                        true,
1723                        Highlights::default(),
1724                    )
1725                    .map(|c| c.text)
1726                    .collect::<String>();
1727                assert_eq!(
1728                    expected_text,
1729                    actual_text,
1730                    "chunks != highlighted_chunks for rows {:?}",
1731                    start_row..end_row
1732                );
1733            }
1734        }
1735    }
1736}