block_map.rs

   1use super::wrap_map::{self, Edit as WrapEdit, Snapshot as WrapSnapshot, WrapPoint};
   2use buffer::{rope, Anchor, Bias, Edit, Point, Rope, ToOffset, ToPoint as _};
   3use gpui::{fonts::HighlightStyle, AppContext, ModelHandle};
   4use language::{Buffer, Chunk};
   5use parking_lot::Mutex;
   6use std::{
   7    cmp::{self, Ordering},
   8    collections::HashSet,
   9    iter,
  10    ops::Range,
  11    slice,
  12    sync::{
  13        atomic::{AtomicUsize, Ordering::SeqCst},
  14        Arc,
  15    },
  16};
  17use sum_tree::SumTree;
  18use theme::SyntaxTheme;
  19
  20pub struct BlockMap {
  21    buffer: ModelHandle<Buffer>,
  22    next_block_id: AtomicUsize,
  23    wrap_snapshot: Mutex<WrapSnapshot>,
  24    blocks: Vec<Arc<Block>>,
  25    transforms: Mutex<SumTree<Transform>>,
  26}
  27
  28pub struct BlockMapWriter<'a>(&'a mut BlockMap);
  29
  30pub struct BlockSnapshot {
  31    wrap_snapshot: WrapSnapshot,
  32    transforms: SumTree<Transform>,
  33}
  34
  35#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
  36pub struct BlockId(usize);
  37
  38#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  39pub struct BlockPoint(pub super::Point);
  40
  41#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  42struct BlockRow(u32);
  43
  44#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  45struct WrapRow(u32);
  46
  47#[derive(Debug)]
  48struct Block {
  49    id: BlockId,
  50    position: Anchor,
  51    text: Rope,
  52    runs: Vec<(usize, HighlightStyle)>,
  53    disposition: BlockDisposition,
  54}
  55
  56#[derive(Clone)]
  57pub struct BlockProperties<P, T>
  58where
  59    P: Clone,
  60    T: Clone,
  61{
  62    pub position: P,
  63    pub text: T,
  64    pub runs: Vec<(usize, HighlightStyle)>,
  65    pub disposition: BlockDisposition,
  66}
  67
  68#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
  69pub enum BlockDisposition {
  70    Above,
  71    Below,
  72}
  73
  74#[derive(Clone, Debug)]
  75struct Transform {
  76    summary: TransformSummary,
  77    block: Option<Arc<Block>>,
  78}
  79
  80#[derive(Clone, Debug, Default)]
  81struct TransformSummary {
  82    input_rows: u32,
  83    output_rows: u32,
  84    longest_row_in_block: u32,
  85    longest_row_in_block_chars: u32,
  86}
  87
  88pub struct Chunks<'a> {
  89    transforms: sum_tree::Cursor<'a, Transform, (BlockRow, WrapRow)>,
  90    input_chunks: wrap_map::Chunks<'a>,
  91    input_chunk: Chunk<'a>,
  92    block_chunks: Option<BlockChunks<'a>>,
  93    output_row: u32,
  94    max_output_row: u32,
  95}
  96
  97struct BlockChunks<'a> {
  98    chunks: rope::Chunks<'a>,
  99    runs: iter::Peekable<slice::Iter<'a, (usize, HighlightStyle)>>,
 100    chunk: Option<&'a str>,
 101    run_start: usize,
 102    offset: usize,
 103}
 104
 105pub struct BufferRows<'a> {
 106    transforms: sum_tree::Cursor<'a, Transform, (BlockRow, WrapRow)>,
 107    input_buffer_rows: wrap_map::BufferRows<'a>,
 108    output_row: u32,
 109    started: bool,
 110}
 111
 112impl BlockMap {
 113    pub fn new(buffer: ModelHandle<Buffer>, wrap_snapshot: WrapSnapshot) -> Self {
 114        Self {
 115            buffer,
 116            next_block_id: AtomicUsize::new(0),
 117            blocks: Vec::new(),
 118            transforms: Mutex::new(SumTree::from_item(
 119                Transform::isomorphic(wrap_snapshot.text_summary().lines.row + 1),
 120                &(),
 121            )),
 122            wrap_snapshot: Mutex::new(wrap_snapshot),
 123        }
 124    }
 125
 126    pub fn read(
 127        &self,
 128        wrap_snapshot: WrapSnapshot,
 129        edits: Vec<WrapEdit>,
 130        cx: &AppContext,
 131    ) -> BlockSnapshot {
 132        self.sync(&wrap_snapshot, edits, cx);
 133        *self.wrap_snapshot.lock() = wrap_snapshot.clone();
 134        BlockSnapshot {
 135            wrap_snapshot,
 136            transforms: self.transforms.lock().clone(),
 137        }
 138    }
 139
 140    pub fn write(
 141        &mut self,
 142        wrap_snapshot: WrapSnapshot,
 143        edits: Vec<WrapEdit>,
 144        cx: &AppContext,
 145    ) -> BlockMapWriter {
 146        self.sync(&wrap_snapshot, edits, cx);
 147        *self.wrap_snapshot.lock() = wrap_snapshot;
 148        BlockMapWriter(self)
 149    }
 150
 151    pub fn sync(&self, wrap_snapshot: &WrapSnapshot, edits: Vec<WrapEdit>, cx: &AppContext) {
 152        if edits.is_empty() {
 153            return;
 154        }
 155
 156        let buffer = self.buffer.read(cx);
 157        let mut transforms = self.transforms.lock();
 158        let mut new_transforms = SumTree::new();
 159        let old_row_count = transforms.summary().input_rows;
 160        let new_row_count = wrap_snapshot.max_point().row() + 1;
 161        let mut cursor = transforms.cursor::<WrapRow>();
 162        let mut last_block_ix = 0;
 163        let mut blocks_in_edit = Vec::new();
 164        let mut edits = edits.into_iter().peekable();
 165
 166        while let Some(edit) = edits.next() {
 167            // Preserve any old transforms that precede this edit.
 168            let old_start = WrapRow(edit.old.start);
 169            let new_start = WrapRow(edit.new.start);
 170            new_transforms.push_tree(cursor.slice(&old_start, Bias::Left, &()), &());
 171            if let Some(transform) = cursor.item() {
 172                if transform.is_isomorphic() && old_start == cursor.end(&()) {
 173                    new_transforms.push(transform.clone(), &());
 174                    cursor.next(&());
 175                    while let Some(transform) = cursor.item() {
 176                        if transform
 177                            .block
 178                            .as_ref()
 179                            .map_or(false, |b| b.disposition.is_below())
 180                        {
 181                            new_transforms.push(transform.clone(), &());
 182                            cursor.next(&());
 183                        } else {
 184                            break;
 185                        }
 186                    }
 187                }
 188            }
 189
 190            // Preserve any portion of an old transform that precedes this edit.
 191            let extent_before_edit = old_start.0 - cursor.start().0;
 192            push_isomorphic(&mut new_transforms, extent_before_edit);
 193
 194            // Skip over any old transforms that intersect this edit.
 195            let mut old_end = WrapRow(edit.old.end);
 196            let mut new_end = WrapRow(edit.new.end);
 197            cursor.seek(&old_end, Bias::Left, &());
 198            cursor.next(&());
 199            if old_end == *cursor.start() {
 200                while let Some(transform) = cursor.item() {
 201                    if transform
 202                        .block
 203                        .as_ref()
 204                        .map_or(false, |b| b.disposition.is_below())
 205                    {
 206                        cursor.next(&());
 207                    } else {
 208                        break;
 209                    }
 210                }
 211            }
 212
 213            // Combine this edit with any subsequent edits that intersect the same transform.
 214            while let Some(next_edit) = edits.peek() {
 215                if next_edit.old.start <= cursor.start().0 {
 216                    old_end = WrapRow(next_edit.old.end);
 217                    new_end = WrapRow(next_edit.new.end);
 218                    cursor.seek(&old_end, Bias::Left, &());
 219                    cursor.next(&());
 220                    if old_end == *cursor.start() {
 221                        while let Some(transform) = cursor.item() {
 222                            if transform
 223                                .block
 224                                .as_ref()
 225                                .map_or(false, |b| b.disposition.is_below())
 226                            {
 227                                cursor.next(&());
 228                            } else {
 229                                break;
 230                            }
 231                        }
 232                    }
 233                    edits.next();
 234                } else {
 235                    break;
 236                }
 237            }
 238
 239            // Find the blocks within this edited region.
 240            let new_start = wrap_snapshot.to_point(WrapPoint::new(new_start.0, 0), Bias::Left);
 241            let start_anchor = buffer.anchor_before(new_start);
 242            let start_block_ix = match self.blocks[last_block_ix..].binary_search_by(|probe| {
 243                probe
 244                    .position
 245                    .cmp(&start_anchor, buffer)
 246                    .unwrap()
 247                    .then(Ordering::Greater)
 248            }) {
 249                Ok(ix) | Err(ix) => last_block_ix + ix,
 250            };
 251            let end_block_ix = if new_end.0 > wrap_snapshot.max_point().row() {
 252                self.blocks.len()
 253            } else {
 254                let new_end = wrap_snapshot.to_point(WrapPoint::new(new_end.0, 0), Bias::Left);
 255                let end_anchor = buffer.anchor_before(new_end);
 256                match self.blocks[start_block_ix..].binary_search_by(|probe| {
 257                    probe
 258                        .position
 259                        .cmp(&end_anchor, buffer)
 260                        .unwrap()
 261                        .then(Ordering::Greater)
 262                }) {
 263                    Ok(ix) | Err(ix) => start_block_ix + ix,
 264                }
 265            };
 266            last_block_ix = end_block_ix;
 267            blocks_in_edit.clear();
 268            blocks_in_edit.extend(
 269                self.blocks[start_block_ix..end_block_ix]
 270                    .iter()
 271                    .map(|block| {
 272                        let mut position = block.position.to_point(buffer);
 273                        match block.disposition {
 274                            BlockDisposition::Above => position.column = 0,
 275                            BlockDisposition::Below => {
 276                                position.column = buffer.line_len(position.row)
 277                            }
 278                        }
 279                        let position = wrap_snapshot.from_point(position, Bias::Left);
 280                        (position.row(), block)
 281                    }),
 282            );
 283            blocks_in_edit.sort_unstable_by_key(|(row, block)| (*row, block.disposition, block.id));
 284
 285            // For each of these blocks, insert a new isomorphic transform preceding the block,
 286            // and then insert the block itself.
 287            for (block_row, block) in blocks_in_edit.iter().copied() {
 288                let insertion_row = match block.disposition {
 289                    BlockDisposition::Above => block_row,
 290                    BlockDisposition::Below => block_row + 1,
 291                };
 292                let extent_before_block = insertion_row - new_transforms.summary().input_rows;
 293                push_isomorphic(&mut new_transforms, extent_before_block);
 294                new_transforms.push(Transform::block(block.clone()), &());
 295            }
 296
 297            old_end = WrapRow(old_end.0.min(old_row_count));
 298            new_end = WrapRow(new_end.0.min(new_row_count));
 299
 300            // Insert an isomorphic transform after the final block.
 301            let extent_after_last_block = new_end.0 - new_transforms.summary().input_rows;
 302            push_isomorphic(&mut new_transforms, extent_after_last_block);
 303
 304            // Preserve any portion of the old transform after this edit.
 305            let extent_after_edit = cursor.start().0 - old_end.0;
 306            push_isomorphic(&mut new_transforms, extent_after_edit);
 307        }
 308
 309        new_transforms.push_tree(cursor.suffix(&()), &());
 310        debug_assert_eq!(
 311            new_transforms.summary().input_rows,
 312            wrap_snapshot.max_point().row() + 1
 313        );
 314
 315        drop(cursor);
 316        *transforms = new_transforms;
 317    }
 318}
 319
 320fn push_isomorphic(tree: &mut SumTree<Transform>, rows: u32) {
 321    if rows == 0 {
 322        return;
 323    }
 324
 325    let mut extent = Some(rows);
 326    tree.update_last(
 327        |last_transform| {
 328            if last_transform.is_isomorphic() {
 329                let extent = extent.take().unwrap();
 330                last_transform.summary.input_rows += extent;
 331                last_transform.summary.output_rows += extent;
 332            }
 333        },
 334        &(),
 335    );
 336    if let Some(extent) = extent {
 337        tree.push(Transform::isomorphic(extent), &());
 338    }
 339}
 340
 341impl BlockPoint {
 342    pub fn new(row: u32, column: u32) -> Self {
 343        Self(Point::new(row, column))
 344    }
 345}
 346
 347impl std::ops::Deref for BlockPoint {
 348    type Target = Point;
 349
 350    fn deref(&self) -> &Self::Target {
 351        &self.0
 352    }
 353}
 354
 355impl std::ops::DerefMut for BlockPoint {
 356    fn deref_mut(&mut self) -> &mut Self::Target {
 357        &mut self.0
 358    }
 359}
 360
 361impl<'a> BlockMapWriter<'a> {
 362    pub fn insert<P, T>(
 363        &mut self,
 364        blocks: impl IntoIterator<Item = BlockProperties<P, T>>,
 365        cx: &AppContext,
 366    ) -> Vec<BlockId>
 367    where
 368        P: ToOffset + Clone,
 369        T: Into<Rope> + Clone,
 370    {
 371        let buffer = self.0.buffer.read(cx);
 372        let mut ids = Vec::new();
 373        let mut edits = Vec::<Edit<u32>>::new();
 374        let wrap_snapshot = &*self.0.wrap_snapshot.lock();
 375
 376        for block in blocks {
 377            let id = BlockId(self.0.next_block_id.fetch_add(1, SeqCst));
 378            ids.push(id);
 379
 380            let position = buffer.anchor_before(block.position);
 381            let point = position.to_point(buffer);
 382            let start_row = wrap_snapshot
 383                .from_point(Point::new(point.row, 0), Bias::Left)
 384                .row();
 385            let end_row = if point.row == buffer.max_point().row {
 386                wrap_snapshot.max_point().row() + 1
 387            } else {
 388                wrap_snapshot
 389                    .from_point(Point::new(point.row + 1, 0), Bias::Left)
 390                    .row()
 391            };
 392
 393            let block_ix = match self
 394                .0
 395                .blocks
 396                .binary_search_by(|probe| probe.position.cmp(&position, buffer).unwrap())
 397            {
 398                Ok(ix) | Err(ix) => ix,
 399            };
 400            self.0.blocks.insert(
 401                block_ix,
 402                Arc::new(Block {
 403                    id,
 404                    position,
 405                    text: block.text.into(),
 406                    runs: block.runs,
 407                    disposition: block.disposition,
 408                }),
 409            );
 410
 411            if let Err(edit_ix) = edits.binary_search_by_key(&start_row, |edit| edit.old.start) {
 412                edits.insert(
 413                    edit_ix,
 414                    Edit {
 415                        old: start_row..end_row,
 416                        new: start_row..end_row,
 417                    },
 418                );
 419            }
 420        }
 421
 422        self.0.sync(wrap_snapshot, edits, cx);
 423        ids
 424    }
 425
 426    pub fn remove(&mut self, block_ids: HashSet<BlockId>, cx: &AppContext) {
 427        let buffer = self.0.buffer.read(cx);
 428        let wrap_snapshot = &*self.0.wrap_snapshot.lock();
 429        let mut edits = Vec::new();
 430        let mut last_block_buffer_row = None;
 431        self.0.blocks.retain(|block| {
 432            if block_ids.contains(&block.id) {
 433                let buffer_row = block.position.to_point(buffer).row;
 434                if last_block_buffer_row != Some(buffer_row) {
 435                    last_block_buffer_row = Some(buffer_row);
 436                    let start_row = wrap_snapshot
 437                        .from_point(Point::new(buffer_row, 0), Bias::Left)
 438                        .row();
 439                    let end_row = wrap_snapshot
 440                        .from_point(
 441                            Point::new(buffer_row, buffer.line_len(buffer_row)),
 442                            Bias::Left,
 443                        )
 444                        .row()
 445                        + 1;
 446                    edits.push(Edit {
 447                        old: start_row..end_row,
 448                        new: start_row..end_row,
 449                    })
 450                }
 451                false
 452            } else {
 453                true
 454            }
 455        });
 456        self.0.sync(wrap_snapshot, edits, cx);
 457    }
 458}
 459
 460impl BlockSnapshot {
 461    #[cfg(test)]
 462    fn text(&mut self) -> String {
 463        self.chunks(0..self.transforms.summary().output_rows, None)
 464            .map(|chunk| chunk.text)
 465            .collect()
 466    }
 467
 468    pub fn chunks<'a>(&'a self, rows: Range<u32>, theme: Option<&'a SyntaxTheme>) -> Chunks<'a> {
 469        let max_output_row = cmp::min(rows.end, self.transforms.summary().output_rows);
 470        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 471        let input_end = {
 472            cursor.seek(&BlockRow(rows.end), Bias::Right, &());
 473            let overshoot = if cursor
 474                .item()
 475                .map_or(false, |transform| transform.is_isomorphic())
 476            {
 477                rows.end - cursor.start().0 .0
 478            } else {
 479                0
 480            };
 481            cursor.start().1 .0 + overshoot
 482        };
 483        let input_start = {
 484            cursor.seek(&BlockRow(rows.start), Bias::Right, &());
 485            let overshoot = if cursor
 486                .item()
 487                .map_or(false, |transform| transform.is_isomorphic())
 488            {
 489                rows.start - cursor.start().0 .0
 490            } else {
 491                0
 492            };
 493            cursor.start().1 .0 + overshoot
 494        };
 495        Chunks {
 496            input_chunks: self.wrap_snapshot.chunks(input_start..input_end, theme),
 497            input_chunk: Default::default(),
 498            block_chunks: None,
 499            transforms: cursor,
 500            output_row: rows.start,
 501            max_output_row,
 502        }
 503    }
 504
 505    pub fn buffer_rows(&self, start_row: u32) -> BufferRows {
 506        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 507        cursor.seek(&BlockRow(start_row), Bias::Right, &());
 508        let (input_start, output_start) = cursor.start();
 509        let overshoot = if cursor.item().map_or(false, |t| t.is_isomorphic()) {
 510            start_row - output_start.0
 511        } else {
 512            0
 513        };
 514        let input_start_row = input_start.0 + overshoot;
 515        BufferRows {
 516            transforms: cursor,
 517            input_buffer_rows: self.wrap_snapshot.buffer_rows(input_start_row),
 518            output_row: start_row,
 519            started: false,
 520        }
 521    }
 522
 523    pub fn max_point(&self) -> BlockPoint {
 524        let row = self.transforms.summary().output_rows - 1;
 525        BlockPoint::new(row, self.line_len(row))
 526    }
 527
 528    pub fn longest_row(&self) -> u32 {
 529        let input_row = self.wrap_snapshot.longest_row();
 530        let input_row_chars = self.wrap_snapshot.line_char_count(input_row);
 531        let TransformSummary {
 532            longest_row_in_block: block_row,
 533            longest_row_in_block_chars: block_row_chars,
 534            ..
 535        } = &self.transforms.summary();
 536
 537        if *block_row_chars > input_row_chars {
 538            *block_row
 539        } else {
 540            self.to_block_point(WrapPoint::new(input_row, 0)).row
 541        }
 542    }
 543
 544    pub fn line_len(&self, row: u32) -> u32 {
 545        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 546        cursor.seek(&BlockRow(row), Bias::Right, &());
 547        if let Some(transform) = cursor.item() {
 548            let (output_start, input_start) = cursor.start();
 549            let overshoot = row - output_start.0;
 550            if let Some(block) = &transform.block {
 551                block.text.line_len(overshoot)
 552            } else {
 553                self.wrap_snapshot.line_len(input_start.0 + overshoot)
 554            }
 555        } else {
 556            panic!("row out of range");
 557        }
 558    }
 559
 560    pub fn is_block_line(&self, row: u32) -> bool {
 561        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 562        cursor.seek(&BlockRow(row), Bias::Right, &());
 563        cursor.item().map_or(false, |t| t.block.is_some())
 564    }
 565
 566    pub fn clip_point(&self, point: BlockPoint, bias: Bias) -> BlockPoint {
 567        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 568        cursor.seek(&BlockRow(point.row), Bias::Right, &());
 569
 570        let max_input_row = WrapRow(self.transforms.summary().input_rows);
 571        let search_left =
 572            (bias == Bias::Left && cursor.start().1 .0 > 0) || cursor.end(&()).1 == max_input_row;
 573
 574        loop {
 575            if let Some(transform) = cursor.item() {
 576                if transform.is_isomorphic() {
 577                    let (output_start_row, input_start_row) = cursor.start();
 578                    let (output_end_row, input_end_row) = cursor.end(&());
 579
 580                    if point.row >= output_end_row.0 {
 581                        return BlockPoint::new(
 582                            output_end_row.0 - 1,
 583                            self.wrap_snapshot.line_len(input_end_row.0 - 1),
 584                        );
 585                    }
 586
 587                    let output_start = Point::new(output_start_row.0, 0);
 588                    if point.0 > output_start {
 589                        let output_overshoot = point.0 - output_start;
 590                        let input_start = Point::new(input_start_row.0, 0);
 591                        let input_point = self
 592                            .wrap_snapshot
 593                            .clip_point(WrapPoint(input_start + output_overshoot), bias);
 594                        let input_overshoot = input_point.0 - input_start;
 595                        return BlockPoint(output_start + input_overshoot);
 596                    } else {
 597                        return BlockPoint(output_start);
 598                    }
 599                } else if search_left {
 600                    cursor.prev(&());
 601                } else {
 602                    cursor.next(&());
 603                }
 604            } else {
 605                return self.max_point();
 606            }
 607        }
 608    }
 609
 610    pub fn to_block_point(&self, wrap_point: WrapPoint) -> BlockPoint {
 611        let mut cursor = self.transforms.cursor::<(WrapRow, BlockRow)>();
 612        cursor.seek(&WrapRow(wrap_point.row()), Bias::Right, &());
 613        if let Some(transform) = cursor.item() {
 614            debug_assert!(transform.is_isomorphic());
 615        } else {
 616            return self.max_point();
 617        }
 618
 619        let (input_start_row, output_start_row) = cursor.start();
 620        let input_start = Point::new(input_start_row.0, 0);
 621        let output_start = Point::new(output_start_row.0, 0);
 622        let input_overshoot = wrap_point.0 - input_start;
 623        BlockPoint(output_start + input_overshoot)
 624    }
 625
 626    pub fn to_wrap_point(&self, block_point: BlockPoint) -> WrapPoint {
 627        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 628        cursor.seek(&BlockRow(block_point.row), Bias::Right, &());
 629        if let Some(transform) = cursor.item() {
 630            match transform.block.as_ref().map(|b| b.disposition) {
 631                Some(BlockDisposition::Above) => WrapPoint::new(cursor.start().1 .0, 0),
 632                Some(BlockDisposition::Below) => {
 633                    let wrap_row = cursor.start().1 .0 - 1;
 634                    WrapPoint::new(wrap_row, self.wrap_snapshot.line_len(wrap_row))
 635                }
 636                None => {
 637                    let overshoot = block_point.row - cursor.start().0 .0;
 638                    let wrap_row = cursor.start().1 .0 + overshoot;
 639                    WrapPoint::new(wrap_row, block_point.column)
 640                }
 641            }
 642        } else {
 643            self.wrap_snapshot.max_point()
 644        }
 645    }
 646}
 647
 648impl Transform {
 649    fn isomorphic(rows: u32) -> Self {
 650        Self {
 651            summary: TransformSummary {
 652                input_rows: rows,
 653                output_rows: rows,
 654                longest_row_in_block: 0,
 655                longest_row_in_block_chars: 0,
 656            },
 657            block: None,
 658        }
 659    }
 660
 661    fn block(block: Arc<Block>) -> Self {
 662        let text_summary = block.text.summary();
 663        Self {
 664            summary: TransformSummary {
 665                input_rows: 0,
 666                output_rows: text_summary.lines.row + 1,
 667                longest_row_in_block: text_summary.longest_row,
 668                longest_row_in_block_chars: text_summary.longest_row_chars,
 669            },
 670            block: Some(block),
 671        }
 672    }
 673
 674    fn is_isomorphic(&self) -> bool {
 675        self.block.is_none()
 676    }
 677}
 678
 679impl<'a> Iterator for Chunks<'a> {
 680    type Item = Chunk<'a>;
 681
 682    fn next(&mut self) -> Option<Self::Item> {
 683        if self.output_row >= self.max_output_row {
 684            return None;
 685        }
 686
 687        if let Some(block_chunks) = self.block_chunks.as_mut() {
 688            if let Some(block_chunk) = block_chunks.next() {
 689                self.output_row += block_chunk.text.matches('\n').count() as u32;
 690                return Some(block_chunk);
 691            } else {
 692                self.block_chunks.take();
 693                self.output_row += 1;
 694                if self.output_row < self.max_output_row {
 695                    return Some(Chunk {
 696                        text: "\n",
 697                        ..Default::default()
 698                    });
 699                } else {
 700                    return None;
 701                }
 702            }
 703        }
 704
 705        let transform = self.transforms.item()?;
 706        if let Some(block) = transform.block.as_ref() {
 707            let block_start = self.transforms.start().0 .0;
 708            let block_end = self.transforms.end(&()).0 .0;
 709            let start_in_block = self.output_row - block_start;
 710            let end_in_block = cmp::min(self.max_output_row, block_end) - block_start;
 711            self.transforms.next(&());
 712            self.block_chunks = Some(BlockChunks::new(block, start_in_block..end_in_block));
 713            return self.next();
 714        }
 715
 716        if self.input_chunk.text.is_empty() {
 717            if let Some(input_chunk) = self.input_chunks.next() {
 718                self.input_chunk = input_chunk;
 719            } else {
 720                self.output_row += 1;
 721                if self.output_row < self.max_output_row {
 722                    self.transforms.next(&());
 723                    return Some(Chunk {
 724                        text: "\n",
 725                        ..Default::default()
 726                    });
 727                } else {
 728                    return None;
 729                }
 730            }
 731        }
 732
 733        let transform_end = self.transforms.end(&()).0 .0;
 734        let (prefix_rows, prefix_bytes) =
 735            offset_for_row(self.input_chunk.text, transform_end - self.output_row);
 736        self.output_row += prefix_rows;
 737        let (prefix, suffix) = self.input_chunk.text.split_at(prefix_bytes);
 738        self.input_chunk.text = suffix;
 739        if self.output_row == transform_end {
 740            self.transforms.next(&());
 741        }
 742
 743        Some(Chunk {
 744            text: prefix,
 745            ..self.input_chunk
 746        })
 747    }
 748}
 749
 750impl<'a> BlockChunks<'a> {
 751    fn new(block: &'a Block, rows: Range<u32>) -> Self {
 752        let offset_range = block.text.point_to_offset(Point::new(rows.start, 0))
 753            ..block.text.point_to_offset(Point::new(rows.end, 0));
 754
 755        let mut runs = block.runs.iter().peekable();
 756        let mut run_start = 0;
 757        while let Some((run_len, _)) = runs.peek() {
 758            let run_end = run_start + run_len;
 759            if run_end <= offset_range.start {
 760                run_start = run_end;
 761                runs.next();
 762            } else {
 763                break;
 764            }
 765        }
 766
 767        Self {
 768            chunk: None,
 769            run_start,
 770            chunks: block.text.chunks_in_range(offset_range.clone()),
 771            runs,
 772            offset: offset_range.start,
 773        }
 774    }
 775}
 776
 777impl<'a> Iterator for BlockChunks<'a> {
 778    type Item = Chunk<'a>;
 779
 780    fn next(&mut self) -> Option<Self::Item> {
 781        if self.chunk.is_none() {
 782            self.chunk = self.chunks.next();
 783        }
 784
 785        let chunk = self.chunk?;
 786        let mut chunk_len = chunk.len();
 787        let mut highlight_style = None;
 788        if let Some((run_len, style)) = self.runs.peek() {
 789            highlight_style = Some(style.clone());
 790            let run_end_in_chunk = self.run_start + run_len - self.offset;
 791            if run_end_in_chunk <= chunk_len {
 792                chunk_len = run_end_in_chunk;
 793                self.run_start += run_len;
 794                self.runs.next();
 795            }
 796        }
 797
 798        self.offset += chunk_len;
 799        let (chunk, suffix) = chunk.split_at(chunk_len);
 800        self.chunk = if suffix.is_empty() {
 801            None
 802        } else {
 803            Some(suffix)
 804        };
 805
 806        Some(Chunk {
 807            text: chunk,
 808            highlight_style,
 809            diagnostic: None,
 810        })
 811    }
 812}
 813
 814impl<'a> Iterator for BufferRows<'a> {
 815    type Item = Option<u32>;
 816
 817    fn next(&mut self) -> Option<Self::Item> {
 818        if self.started {
 819            self.output_row += 1;
 820        } else {
 821            self.started = true;
 822        }
 823
 824        if self.output_row >= self.transforms.end(&()).0 .0 {
 825            self.transforms.next(&());
 826        }
 827
 828        let transform = self.transforms.item()?;
 829        if transform.is_isomorphic() {
 830            Some(self.input_buffer_rows.next().unwrap())
 831        } else {
 832            Some(None)
 833        }
 834    }
 835}
 836
 837impl sum_tree::Item for Transform {
 838    type Summary = TransformSummary;
 839
 840    fn summary(&self) -> Self::Summary {
 841        self.summary.clone()
 842    }
 843}
 844
 845impl sum_tree::Summary for TransformSummary {
 846    type Context = ();
 847
 848    fn add_summary(&mut self, summary: &Self, _: &()) {
 849        if summary.longest_row_in_block_chars > self.longest_row_in_block_chars {
 850            self.longest_row_in_block_chars = summary.longest_row_in_block_chars;
 851            self.longest_row_in_block = self.output_rows + summary.longest_row_in_block;
 852        }
 853
 854        self.input_rows += summary.input_rows;
 855        self.output_rows += summary.output_rows;
 856    }
 857}
 858
 859impl<'a> sum_tree::Dimension<'a, TransformSummary> for WrapRow {
 860    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
 861        self.0 += summary.input_rows;
 862    }
 863}
 864
 865impl<'a> sum_tree::Dimension<'a, TransformSummary> for BlockRow {
 866    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
 867        self.0 += summary.output_rows;
 868    }
 869}
 870
 871impl BlockDisposition {
 872    fn is_below(&self) -> bool {
 873        matches!(self, BlockDisposition::Below)
 874    }
 875}
 876
 877// Count the number of bytes prior to a target point. If the string doesn't contain the target
 878// point, return its total extent. Otherwise return the target point itself.
 879fn offset_for_row(s: &str, target: u32) -> (u32, usize) {
 880    let mut row = 0;
 881    let mut offset = 0;
 882    for (ix, line) in s.split('\n').enumerate() {
 883        if ix > 0 {
 884            row += 1;
 885            offset += 1;
 886        }
 887        if row >= target {
 888            break;
 889        }
 890        offset += line.len() as usize;
 891    }
 892    (row, offset)
 893}
 894
 895#[cfg(test)]
 896mod tests {
 897    use super::*;
 898    use crate::display_map::{fold_map::FoldMap, tab_map::TabMap, wrap_map::WrapMap};
 899    use buffer::RandomCharIter;
 900    use language::Buffer;
 901    use rand::prelude::*;
 902    use std::env;
 903
 904    #[gpui::test]
 905    fn test_offset_for_row() {
 906        assert_eq!(offset_for_row("", 0), (0, 0));
 907        assert_eq!(offset_for_row("", 1), (0, 0));
 908        assert_eq!(offset_for_row("abcd", 0), (0, 0));
 909        assert_eq!(offset_for_row("abcd", 1), (0, 4));
 910        assert_eq!(offset_for_row("\n", 0), (0, 0));
 911        assert_eq!(offset_for_row("\n", 1), (1, 1));
 912        assert_eq!(offset_for_row("abc\ndef\nghi", 0), (0, 0));
 913        assert_eq!(offset_for_row("abc\ndef\nghi", 1), (1, 4));
 914        assert_eq!(offset_for_row("abc\ndef\nghi", 2), (2, 8));
 915        assert_eq!(offset_for_row("abc\ndef\nghi", 3), (2, 11));
 916    }
 917
 918    #[gpui::test]
 919    fn test_basic_blocks(cx: &mut gpui::MutableAppContext) {
 920        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
 921        let font_id = cx
 922            .font_cache()
 923            .select_font(family_id, &Default::default())
 924            .unwrap();
 925
 926        let text = "aaa\nbbb\nccc\nddd";
 927
 928        let buffer = cx.add_model(|cx| Buffer::new(0, text, cx));
 929        let (fold_map, folds_snapshot) = FoldMap::new(buffer.clone(), cx);
 930        let (tab_map, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), 1);
 931        let (wrap_map, wraps_snapshot) = WrapMap::new(tabs_snapshot, font_id, 14.0, None, cx);
 932        let mut block_map = BlockMap::new(buffer.clone(), wraps_snapshot.clone());
 933
 934        let mut writer = block_map.write(wraps_snapshot.clone(), vec![], cx);
 935        writer.insert(
 936            vec![
 937                BlockProperties {
 938                    position: Point::new(1, 0),
 939                    text: "BLOCK 1",
 940                    disposition: BlockDisposition::Above,
 941                    runs: vec![],
 942                },
 943                BlockProperties {
 944                    position: Point::new(1, 2),
 945                    text: "BLOCK 2",
 946                    disposition: BlockDisposition::Above,
 947                    runs: vec![],
 948                },
 949                BlockProperties {
 950                    position: Point::new(3, 2),
 951                    text: "BLOCK 3",
 952                    disposition: BlockDisposition::Below,
 953                    runs: vec![],
 954                },
 955            ],
 956            cx,
 957        );
 958
 959        let mut snapshot = block_map.read(wraps_snapshot, vec![], cx);
 960        assert_eq!(
 961            snapshot.text(),
 962            "aaa\nBLOCK 1\nBLOCK 2\nbbb\nccc\nddd\nBLOCK 3"
 963        );
 964        assert_eq!(
 965            snapshot.to_block_point(WrapPoint::new(0, 3)),
 966            BlockPoint::new(0, 3)
 967        );
 968        assert_eq!(
 969            snapshot.to_block_point(WrapPoint::new(1, 0)),
 970            BlockPoint::new(3, 0)
 971        );
 972        assert_eq!(
 973            snapshot.to_block_point(WrapPoint::new(3, 3)),
 974            BlockPoint::new(5, 3)
 975        );
 976
 977        assert_eq!(
 978            snapshot.to_wrap_point(BlockPoint::new(0, 3)),
 979            WrapPoint::new(0, 3)
 980        );
 981        assert_eq!(
 982            snapshot.to_wrap_point(BlockPoint::new(1, 0)),
 983            WrapPoint::new(1, 0)
 984        );
 985        assert_eq!(
 986            snapshot.to_wrap_point(BlockPoint::new(3, 0)),
 987            WrapPoint::new(1, 0)
 988        );
 989        assert_eq!(
 990            snapshot.to_wrap_point(BlockPoint::new(6, 0)),
 991            WrapPoint::new(3, 3)
 992        );
 993
 994        assert_eq!(
 995            snapshot.clip_point(BlockPoint::new(1, 0), Bias::Left),
 996            BlockPoint::new(0, 3)
 997        );
 998        assert_eq!(
 999            snapshot.clip_point(BlockPoint::new(1, 0), Bias::Right),
1000            BlockPoint::new(3, 0)
1001        );
1002        assert_eq!(
1003            snapshot.clip_point(BlockPoint::new(1, 1), Bias::Left),
1004            BlockPoint::new(0, 3)
1005        );
1006        assert_eq!(
1007            snapshot.clip_point(BlockPoint::new(1, 1), Bias::Right),
1008            BlockPoint::new(3, 0)
1009        );
1010        assert_eq!(
1011            snapshot.clip_point(BlockPoint::new(3, 0), Bias::Left),
1012            BlockPoint::new(3, 0)
1013        );
1014        assert_eq!(
1015            snapshot.clip_point(BlockPoint::new(3, 0), Bias::Right),
1016            BlockPoint::new(3, 0)
1017        );
1018        assert_eq!(
1019            snapshot.clip_point(BlockPoint::new(5, 3), Bias::Left),
1020            BlockPoint::new(5, 3)
1021        );
1022        assert_eq!(
1023            snapshot.clip_point(BlockPoint::new(5, 3), Bias::Right),
1024            BlockPoint::new(5, 3)
1025        );
1026        assert_eq!(
1027            snapshot.clip_point(BlockPoint::new(6, 0), Bias::Left),
1028            BlockPoint::new(5, 3)
1029        );
1030        assert_eq!(
1031            snapshot.clip_point(BlockPoint::new(6, 0), Bias::Right),
1032            BlockPoint::new(5, 3)
1033        );
1034
1035        assert_eq!(
1036            snapshot.buffer_rows(0).collect::<Vec<_>>(),
1037            &[Some(0), None, None, Some(1), Some(2), Some(3), None]
1038        );
1039
1040        // Insert a line break, separating two block decorations into separate
1041        // lines.
1042        buffer.update(cx, |buffer, cx| {
1043            buffer.edit([Point::new(1, 1)..Point::new(1, 1)], "!!!\n", cx)
1044        });
1045
1046        let (folds_snapshot, fold_edits) = fold_map.read(cx);
1047        let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1048        let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1049            wrap_map.sync(tabs_snapshot, tab_edits, cx)
1050        });
1051        let mut snapshot = block_map.read(wraps_snapshot, wrap_edits, cx);
1052        assert_eq!(
1053            snapshot.text(),
1054            "aaa\nBLOCK 1\nb!!!\nBLOCK 2\nbb\nccc\nddd\nBLOCK 3"
1055        );
1056    }
1057
1058    #[gpui::test]
1059    fn test_blocks_on_wrapped_lines(cx: &mut gpui::MutableAppContext) {
1060        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
1061        let font_id = cx
1062            .font_cache()
1063            .select_font(family_id, &Default::default())
1064            .unwrap();
1065
1066        let text = "one two three\nfour five six\nseven eight";
1067
1068        let buffer = cx.add_model(|cx| Buffer::new(0, text, cx));
1069        let (_, folds_snapshot) = FoldMap::new(buffer.clone(), cx);
1070        let (_, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), 1);
1071        let (_, wraps_snapshot) = WrapMap::new(tabs_snapshot, font_id, 14.0, Some(60.), cx);
1072        let mut block_map = BlockMap::new(buffer.clone(), wraps_snapshot.clone());
1073
1074        let mut writer = block_map.write(wraps_snapshot.clone(), vec![], cx);
1075        writer.insert(
1076            vec![
1077                BlockProperties {
1078                    position: Point::new(1, 12),
1079                    text: "<BLOCK 1",
1080                    disposition: BlockDisposition::Above,
1081                    runs: vec![],
1082                },
1083                BlockProperties {
1084                    position: Point::new(1, 1),
1085                    text: ">BLOCK 2",
1086                    disposition: BlockDisposition::Below,
1087                    runs: vec![],
1088                },
1089            ],
1090            cx,
1091        );
1092
1093        // Blocks with an 'above' disposition go above their corresponding buffer line.
1094        // Blocks with a 'below' disposition go below their corresponding buffer line.
1095        let mut snapshot = block_map.read(wraps_snapshot, vec![], cx);
1096        assert_eq!(
1097            snapshot.text(),
1098            "one two \nthree\n<BLOCK 1\nfour five \nsix\n>BLOCK 2\nseven \neight"
1099        );
1100    }
1101
1102    #[gpui::test(iterations = 100)]
1103    fn test_random_blocks(cx: &mut gpui::MutableAppContext, mut rng: StdRng) {
1104        let operations = env::var("OPERATIONS")
1105            .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
1106            .unwrap_or(10);
1107
1108        let wrap_width = if rng.gen_bool(0.2) {
1109            None
1110        } else {
1111            Some(rng.gen_range(0.0..=100.0))
1112        };
1113        let tab_size = 1;
1114        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
1115        let font_id = cx
1116            .font_cache()
1117            .select_font(family_id, &Default::default())
1118            .unwrap();
1119        let font_size = 14.0;
1120
1121        log::info!("Wrap width: {:?}", wrap_width);
1122
1123        let buffer = cx.add_model(|cx| {
1124            let len = rng.gen_range(0..10);
1125            let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
1126            log::info!("initial buffer text: {:?}", text);
1127            Buffer::new(0, text, cx)
1128        });
1129        let (fold_map, folds_snapshot) = FoldMap::new(buffer.clone(), cx);
1130        let (tab_map, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), tab_size);
1131        let (wrap_map, wraps_snapshot) =
1132            WrapMap::new(tabs_snapshot, font_id, font_size, wrap_width, cx);
1133        let mut block_map = BlockMap::new(buffer.clone(), wraps_snapshot);
1134        let mut expected_blocks = Vec::new();
1135
1136        for _ in 0..operations {
1137            match rng.gen_range(0..=100) {
1138                0..=19 => {
1139                    let wrap_width = if rng.gen_bool(0.2) {
1140                        None
1141                    } else {
1142                        Some(rng.gen_range(0.0..=100.0))
1143                    };
1144                    log::info!("Setting wrap width to {:?}", wrap_width);
1145                    wrap_map.update(cx, |map, cx| map.set_wrap_width(wrap_width, cx));
1146                }
1147                20..=39 => {
1148                    let block_count = rng.gen_range(1..=1);
1149                    let block_properties = (0..block_count)
1150                        .map(|_| {
1151                            let buffer = buffer.read(cx);
1152                            let position = buffer.anchor_before(
1153                                buffer.clip_offset(rng.gen_range(0..=buffer.len()), Bias::Left),
1154                            );
1155
1156                            let len = rng.gen_range(0..10);
1157                            let mut text = Rope::from(
1158                                RandomCharIter::new(&mut rng)
1159                                    .take(len)
1160                                    .collect::<String>()
1161                                    .to_uppercase()
1162                                    .as_str(),
1163                            );
1164                            let disposition = if rng.gen() {
1165                                text.push_front("<");
1166                                BlockDisposition::Above
1167                            } else {
1168                                text.push_front(">");
1169                                BlockDisposition::Below
1170                            };
1171                            log::info!(
1172                                "inserting block {:?} {:?} with text {:?}",
1173                                disposition,
1174                                position.to_point(buffer),
1175                                text.to_string()
1176                            );
1177                            BlockProperties {
1178                                position,
1179                                text,
1180                                runs: Vec::<(usize, HighlightStyle)>::new(),
1181                                disposition,
1182                            }
1183                        })
1184                        .collect::<Vec<_>>();
1185
1186                    let (folds_snapshot, fold_edits) = fold_map.read(cx);
1187                    let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1188                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1189                        wrap_map.sync(tabs_snapshot, tab_edits, cx)
1190                    });
1191                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits, cx);
1192                    let block_ids = block_map.insert(block_properties.clone(), cx);
1193                    for (block_id, props) in block_ids.into_iter().zip(block_properties) {
1194                        expected_blocks.push((block_id, props));
1195                    }
1196                }
1197                40..=59 if !expected_blocks.is_empty() => {
1198                    let block_count = rng.gen_range(1..=4.min(expected_blocks.len()));
1199                    let block_ids_to_remove = (0..block_count)
1200                        .map(|_| {
1201                            expected_blocks
1202                                .remove(rng.gen_range(0..expected_blocks.len()))
1203                                .0
1204                        })
1205                        .collect();
1206
1207                    let (folds_snapshot, fold_edits) = fold_map.read(cx);
1208                    let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1209                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1210                        wrap_map.sync(tabs_snapshot, tab_edits, cx)
1211                    });
1212                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits, cx);
1213                    block_map.remove(block_ids_to_remove, cx);
1214                }
1215                _ => {
1216                    buffer.update(cx, |buffer, _| {
1217                        buffer.randomly_edit(&mut rng, 1);
1218                        log::info!("buffer text: {:?}", buffer.text());
1219                    });
1220                }
1221            }
1222
1223            let (folds_snapshot, fold_edits) = fold_map.read(cx);
1224            let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1225            let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1226                wrap_map.sync(tabs_snapshot, tab_edits, cx)
1227            });
1228            let mut blocks_snapshot = block_map.read(wraps_snapshot.clone(), wrap_edits, cx);
1229            assert_eq!(
1230                blocks_snapshot.transforms.summary().input_rows,
1231                wraps_snapshot.max_point().row() + 1
1232            );
1233            log::info!("blocks text: {:?}", blocks_snapshot.text());
1234
1235            let buffer = buffer.read(cx);
1236            let mut sorted_blocks = expected_blocks
1237                .iter()
1238                .cloned()
1239                .map(|(id, block)| {
1240                    let mut position = block.position.to_point(buffer);
1241                    match block.disposition {
1242                        BlockDisposition::Above => {
1243                            position.column = 0;
1244                        }
1245                        BlockDisposition::Below => {
1246                            position.column = buffer.line_len(position.row);
1247                        }
1248                    };
1249                    let row = wraps_snapshot.from_point(position, Bias::Left).row();
1250                    (
1251                        id,
1252                        BlockProperties {
1253                            position: row,
1254                            text: block.text,
1255                            runs: block.runs,
1256                            disposition: block.disposition,
1257                        },
1258                    )
1259                })
1260                .collect::<Vec<_>>();
1261            sorted_blocks
1262                .sort_unstable_by_key(|(id, block)| (block.position, block.disposition, *id));
1263            let mut sorted_blocks = sorted_blocks.into_iter().peekable();
1264
1265            let mut expected_buffer_rows = Vec::new();
1266            let mut expected_text = String::new();
1267            let input_text = wraps_snapshot.text();
1268            for (row, input_line) in input_text.split('\n').enumerate() {
1269                let row = row as u32;
1270                if row > 0 {
1271                    expected_text.push('\n');
1272                }
1273
1274                let buffer_row = wraps_snapshot
1275                    .to_point(WrapPoint::new(row, 0), Bias::Left)
1276                    .row;
1277
1278                while let Some((_, block)) = sorted_blocks.peek() {
1279                    if block.position == row && block.disposition == BlockDisposition::Above {
1280                        let text = block.text.to_string();
1281                        expected_text.push_str(&text);
1282                        expected_text.push('\n');
1283                        for _ in text.split('\n') {
1284                            expected_buffer_rows.push(None);
1285                        }
1286                        sorted_blocks.next();
1287                    } else {
1288                        break;
1289                    }
1290                }
1291
1292                let soft_wrapped = wraps_snapshot.to_tab_point(WrapPoint::new(row, 0)).column() > 0;
1293                expected_buffer_rows.push(if soft_wrapped { None } else { Some(buffer_row) });
1294                expected_text.push_str(input_line);
1295
1296                while let Some((_, block)) = sorted_blocks.peek() {
1297                    if block.position == row && block.disposition == BlockDisposition::Below {
1298                        let text = block.text.to_string();
1299                        expected_text.push('\n');
1300                        expected_text.push_str(&text);
1301                        for _ in text.split('\n') {
1302                            expected_buffer_rows.push(None);
1303                        }
1304                        sorted_blocks.next();
1305                    } else {
1306                        break;
1307                    }
1308                }
1309            }
1310
1311            let expected_lines = expected_text.split('\n').collect::<Vec<_>>();
1312            let expected_row_count = expected_lines.len();
1313            for start_row in 0..expected_row_count {
1314                let expected_text = expected_lines[start_row..].join("\n");
1315                let actual_text = blocks_snapshot
1316                    .chunks(start_row as u32..expected_row_count as u32, None)
1317                    .map(|chunk| chunk.text)
1318                    .collect::<String>();
1319                assert_eq!(
1320                    actual_text, expected_text,
1321                    "incorrect text starting from row {}",
1322                    start_row
1323                );
1324            }
1325
1326            let mut expected_longest_rows = Vec::new();
1327            let mut longest_line_len = -1_isize;
1328            for (row, line) in expected_lines.iter().enumerate() {
1329                let row = row as u32;
1330
1331                assert_eq!(
1332                    blocks_snapshot.line_len(row),
1333                    line.len() as u32,
1334                    "invalid line len for row {}",
1335                    row
1336                );
1337
1338                let line_char_count = line.chars().count() as isize;
1339                match line_char_count.cmp(&longest_line_len) {
1340                    Ordering::Less => {}
1341                    Ordering::Equal => expected_longest_rows.push(row),
1342                    Ordering::Greater => {
1343                        longest_line_len = line_char_count;
1344                        expected_longest_rows.clear();
1345                        expected_longest_rows.push(row);
1346                    }
1347                }
1348            }
1349
1350            log::info!("getting longest row >>>>>>>>>>>>>>>>>>>>>>>>");
1351            let longest_row = blocks_snapshot.longest_row();
1352            assert!(
1353                expected_longest_rows.contains(&longest_row),
1354                "incorrect longest row {}. expected {:?} with length {}",
1355                longest_row,
1356                expected_longest_rows,
1357                longest_line_len,
1358            );
1359
1360            for row in 0..=blocks_snapshot.wrap_snapshot.max_point().row() {
1361                let wrap_point = WrapPoint::new(row, 0);
1362                let block_point = blocks_snapshot.to_block_point(wrap_point);
1363                assert_eq!(blocks_snapshot.to_wrap_point(block_point), wrap_point);
1364            }
1365            assert_eq!(
1366                blocks_snapshot.buffer_rows(0).collect::<Vec<_>>(),
1367                expected_buffer_rows
1368            );
1369
1370            let mut block_point = BlockPoint::new(0, 0);
1371            for c in expected_text.chars() {
1372                let left_point = blocks_snapshot.clip_point(block_point, Bias::Left);
1373                let right_point = blocks_snapshot.clip_point(block_point, Bias::Right);
1374
1375                assert_eq!(
1376                    blocks_snapshot.to_block_point(blocks_snapshot.to_wrap_point(left_point)),
1377                    left_point
1378                );
1379                assert_eq!(
1380                    blocks_snapshot.to_block_point(blocks_snapshot.to_wrap_point(right_point)),
1381                    right_point
1382                );
1383
1384                if c == '\n' {
1385                    block_point.0 += Point::new(1, 0);
1386                } else {
1387                    block_point.column += c.len_utf8() as u32;
1388                }
1389            }
1390        }
1391    }
1392}