block_map.rs

   1use super::{
   2    wrap_map::{self, WrapEdit, WrapPoint, WrapSnapshot},
   3    Highlights,
   4};
   5use crate::{EditorStyle, GutterDimensions};
   6use collections::{Bound, HashMap, HashSet};
   7use gpui::{AnyElement, EntityId, Pixels, WindowContext};
   8use language::{BufferSnapshot, Chunk, Patch, Point};
   9use multi_buffer::{Anchor, ExcerptId, ExcerptRange, MultiBufferRow, ToPoint as _};
  10use parking_lot::Mutex;
  11use std::{
  12    cell::RefCell,
  13    cmp::{self, Ordering},
  14    fmt::Debug,
  15    ops::{Deref, DerefMut, Range, RangeBounds},
  16    sync::{
  17        atomic::{AtomicUsize, Ordering::SeqCst},
  18        Arc,
  19    },
  20};
  21use sum_tree::{Bias, SumTree, TreeMap};
  22use text::Edit;
  23use ui::ElementId;
  24
  25const NEWLINES: &[u8] = &[b'\n'; u8::MAX as usize];
  26const BULLETS: &str = "********************************************************************************************************************************";
  27
  28/// Tracks custom blocks such as diagnostics that should be displayed within buffer.
  29///
  30/// See the [`display_map` module documentation](crate::display_map) for more information.
  31pub struct BlockMap {
  32    next_block_id: AtomicUsize,
  33    wrap_snapshot: RefCell<WrapSnapshot>,
  34    custom_blocks: Vec<Arc<CustomBlock>>,
  35    custom_blocks_by_id: TreeMap<CustomBlockId, Arc<CustomBlock>>,
  36    transforms: RefCell<SumTree<Transform>>,
  37    show_excerpt_controls: bool,
  38    buffer_header_height: u8,
  39    excerpt_header_height: u8,
  40    excerpt_footer_height: u8,
  41}
  42
  43pub struct BlockMapReader<'a> {
  44    blocks: &'a Vec<Arc<CustomBlock>>,
  45    pub snapshot: BlockSnapshot,
  46}
  47
  48pub struct BlockMapWriter<'a>(&'a mut BlockMap);
  49
  50#[derive(Clone)]
  51pub struct BlockSnapshot {
  52    wrap_snapshot: WrapSnapshot,
  53    transforms: SumTree<Transform>,
  54    custom_blocks_by_id: TreeMap<CustomBlockId, Arc<CustomBlock>>,
  55}
  56
  57#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
  58pub struct CustomBlockId(usize);
  59
  60impl Into<ElementId> for CustomBlockId {
  61    fn into(self) -> ElementId {
  62        ElementId::Integer(self.0)
  63    }
  64}
  65
  66#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  67pub struct BlockPoint(pub Point);
  68
  69#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  70pub struct BlockRow(pub(super) u32);
  71
  72#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  73struct WrapRow(u32);
  74
  75pub type RenderBlock = Box<dyn Send + FnMut(&mut BlockContext) -> AnyElement>;
  76
  77pub struct CustomBlock {
  78    id: CustomBlockId,
  79    position: Anchor,
  80    height: u8,
  81    style: BlockStyle,
  82    render: Mutex<RenderBlock>,
  83    disposition: BlockDisposition,
  84}
  85
  86pub struct BlockProperties<P> {
  87    pub position: P,
  88    pub height: u8,
  89    pub style: BlockStyle,
  90    pub render: RenderBlock,
  91    pub disposition: BlockDisposition,
  92}
  93
  94impl<P: Debug> Debug for BlockProperties<P> {
  95    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
  96        f.debug_struct("BlockProperties")
  97            .field("position", &self.position)
  98            .field("height", &self.height)
  99            .field("style", &self.style)
 100            .field("disposition", &self.disposition)
 101            .finish()
 102    }
 103}
 104
 105#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd)]
 106pub enum BlockStyle {
 107    Fixed,
 108    Flex,
 109    Sticky,
 110}
 111
 112pub struct BlockContext<'a, 'b> {
 113    pub context: &'b mut WindowContext<'a>,
 114    pub anchor_x: Pixels,
 115    pub max_width: Pixels,
 116    pub gutter_dimensions: &'b GutterDimensions,
 117    pub em_width: Pixels,
 118    pub line_height: Pixels,
 119    pub block_id: BlockId,
 120    pub editor_style: &'b EditorStyle,
 121}
 122
 123#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 124pub enum BlockId {
 125    Custom(CustomBlockId),
 126    ExcerptHeader(ExcerptId),
 127    ExcerptFooter(ExcerptId),
 128}
 129
 130impl From<BlockId> for EntityId {
 131    fn from(value: BlockId) -> Self {
 132        match value {
 133            BlockId::Custom(CustomBlockId(id)) => EntityId::from(id as u64),
 134            BlockId::ExcerptHeader(id) => id.into(),
 135            BlockId::ExcerptFooter(id) => id.into(),
 136        }
 137    }
 138}
 139
 140impl From<BlockId> for ElementId {
 141    fn from(value: BlockId) -> Self {
 142        match value {
 143            BlockId::Custom(CustomBlockId(id)) => ("Block", id).into(),
 144            BlockId::ExcerptHeader(id) => ("ExcerptHeader", EntityId::from(id)).into(),
 145            BlockId::ExcerptFooter(id) => ("ExcerptFooter", EntityId::from(id)).into(),
 146        }
 147    }
 148}
 149
 150impl std::fmt::Display for BlockId {
 151    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 152        match self {
 153            Self::Custom(id) => write!(f, "Block({id:?})"),
 154            Self::ExcerptHeader(id) => write!(f, "ExcerptHeader({id:?})"),
 155            Self::ExcerptFooter(id) => write!(f, "ExcerptFooter({id:?})"),
 156        }
 157    }
 158}
 159
 160/// Whether the block should be considered above or below the anchor line
 161#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
 162pub enum BlockDisposition {
 163    Above,
 164    Below,
 165}
 166
 167#[derive(Clone, Debug)]
 168struct Transform {
 169    summary: TransformSummary,
 170    block: Option<Block>,
 171}
 172
 173pub(crate) enum BlockType {
 174    Custom(CustomBlockId),
 175    Header,
 176    Footer,
 177}
 178
 179pub(crate) trait BlockLike {
 180    fn block_type(&self) -> BlockType;
 181    fn disposition(&self) -> BlockDisposition;
 182}
 183
 184#[allow(clippy::large_enum_variant)]
 185#[derive(Clone)]
 186pub enum Block {
 187    Custom(Arc<CustomBlock>),
 188    ExcerptHeader {
 189        id: ExcerptId,
 190        buffer: BufferSnapshot,
 191        range: ExcerptRange<text::Anchor>,
 192        height: u8,
 193        starts_new_buffer: bool,
 194        show_excerpt_controls: bool,
 195    },
 196    ExcerptFooter {
 197        id: ExcerptId,
 198        disposition: BlockDisposition,
 199        height: u8,
 200    },
 201}
 202
 203impl BlockLike for Block {
 204    fn block_type(&self) -> BlockType {
 205        match self {
 206            Block::Custom(block) => BlockType::Custom(block.id),
 207            Block::ExcerptHeader { .. } => BlockType::Header,
 208            Block::ExcerptFooter { .. } => BlockType::Footer,
 209        }
 210    }
 211
 212    fn disposition(&self) -> BlockDisposition {
 213        self.disposition()
 214    }
 215}
 216
 217impl Block {
 218    pub fn id(&self) -> BlockId {
 219        match self {
 220            Block::Custom(block) => BlockId::Custom(block.id),
 221            Block::ExcerptHeader { id, .. } => BlockId::ExcerptHeader(*id),
 222            Block::ExcerptFooter { id, .. } => BlockId::ExcerptFooter(*id),
 223        }
 224    }
 225
 226    fn disposition(&self) -> BlockDisposition {
 227        match self {
 228            Block::Custom(block) => block.disposition,
 229            Block::ExcerptHeader { .. } => BlockDisposition::Above,
 230            Block::ExcerptFooter { disposition, .. } => *disposition,
 231        }
 232    }
 233
 234    pub fn height(&self) -> u8 {
 235        match self {
 236            Block::Custom(block) => block.height,
 237            Block::ExcerptHeader { height, .. } => *height,
 238            Block::ExcerptFooter { height, .. } => *height,
 239        }
 240    }
 241
 242    pub fn style(&self) -> BlockStyle {
 243        match self {
 244            Block::Custom(block) => block.style,
 245            Block::ExcerptHeader { .. } => BlockStyle::Sticky,
 246            Block::ExcerptFooter { .. } => BlockStyle::Sticky,
 247        }
 248    }
 249}
 250
 251impl Debug for Block {
 252    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 253        match self {
 254            Self::Custom(block) => f.debug_struct("Custom").field("block", block).finish(),
 255            Self::ExcerptHeader {
 256                buffer,
 257                starts_new_buffer,
 258                id,
 259                ..
 260            } => f
 261                .debug_struct("ExcerptHeader")
 262                .field("id", &id)
 263                .field("path", &buffer.file().map(|f| f.path()))
 264                .field("starts_new_buffer", &starts_new_buffer)
 265                .finish(),
 266            Block::ExcerptFooter {
 267                id, disposition, ..
 268            } => f
 269                .debug_struct("ExcerptFooter")
 270                .field("id", &id)
 271                .field("disposition", &disposition)
 272                .finish(),
 273        }
 274    }
 275}
 276
 277#[derive(Clone, Debug, Default)]
 278struct TransformSummary {
 279    input_rows: u32,
 280    output_rows: u32,
 281}
 282
 283pub struct BlockChunks<'a> {
 284    transforms: sum_tree::Cursor<'a, Transform, (BlockRow, WrapRow)>,
 285    input_chunks: wrap_map::WrapChunks<'a>,
 286    input_chunk: Chunk<'a>,
 287    output_row: u32,
 288    max_output_row: u32,
 289    masked: bool,
 290}
 291
 292#[derive(Clone)]
 293pub struct BlockBufferRows<'a> {
 294    transforms: sum_tree::Cursor<'a, Transform, (BlockRow, WrapRow)>,
 295    input_buffer_rows: wrap_map::WrapBufferRows<'a>,
 296    output_row: BlockRow,
 297    started: bool,
 298}
 299
 300impl BlockMap {
 301    pub fn new(
 302        wrap_snapshot: WrapSnapshot,
 303        show_excerpt_controls: bool,
 304        buffer_header_height: u8,
 305        excerpt_header_height: u8,
 306        excerpt_footer_height: u8,
 307    ) -> Self {
 308        let row_count = wrap_snapshot.max_point().row() + 1;
 309        let map = Self {
 310            next_block_id: AtomicUsize::new(0),
 311            custom_blocks: Vec::new(),
 312            custom_blocks_by_id: TreeMap::default(),
 313            transforms: RefCell::new(SumTree::from_item(Transform::isomorphic(row_count), &())),
 314            wrap_snapshot: RefCell::new(wrap_snapshot.clone()),
 315            show_excerpt_controls,
 316            buffer_header_height,
 317            excerpt_header_height,
 318            excerpt_footer_height,
 319        };
 320        map.sync(
 321            &wrap_snapshot,
 322            Patch::new(vec![Edit {
 323                old: 0..row_count,
 324                new: 0..row_count,
 325            }]),
 326        );
 327        map
 328    }
 329
 330    pub fn read(&self, wrap_snapshot: WrapSnapshot, edits: Patch<u32>) -> BlockMapReader {
 331        self.sync(&wrap_snapshot, edits);
 332        *self.wrap_snapshot.borrow_mut() = wrap_snapshot.clone();
 333        BlockMapReader {
 334            blocks: &self.custom_blocks,
 335            snapshot: BlockSnapshot {
 336                wrap_snapshot,
 337                transforms: self.transforms.borrow().clone(),
 338                custom_blocks_by_id: self.custom_blocks_by_id.clone(),
 339            },
 340        }
 341    }
 342
 343    pub fn write(&mut self, wrap_snapshot: WrapSnapshot, edits: Patch<u32>) -> BlockMapWriter {
 344        self.sync(&wrap_snapshot, edits);
 345        *self.wrap_snapshot.borrow_mut() = wrap_snapshot;
 346        BlockMapWriter(self)
 347    }
 348
 349    fn sync(&self, wrap_snapshot: &WrapSnapshot, mut edits: Patch<u32>) {
 350        let buffer = wrap_snapshot.buffer_snapshot();
 351
 352        // Handle changing the last excerpt if it is empty.
 353        if buffer.trailing_excerpt_update_count()
 354            != self
 355                .wrap_snapshot
 356                .borrow()
 357                .buffer_snapshot()
 358                .trailing_excerpt_update_count()
 359        {
 360            let max_point = wrap_snapshot.max_point();
 361            let edit_start = wrap_snapshot.prev_row_boundary(max_point);
 362            let edit_end = max_point.row() + 1;
 363            edits = edits.compose([WrapEdit {
 364                old: edit_start..edit_end,
 365                new: edit_start..edit_end,
 366            }]);
 367        }
 368
 369        let edits = edits.into_inner();
 370        if edits.is_empty() {
 371            return;
 372        }
 373
 374        let mut transforms = self.transforms.borrow_mut();
 375        let mut new_transforms = SumTree::new();
 376        let old_row_count = transforms.summary().input_rows;
 377        let new_row_count = wrap_snapshot.max_point().row() + 1;
 378        let mut cursor = transforms.cursor::<WrapRow>();
 379        let mut last_block_ix = 0;
 380        let mut blocks_in_edit = Vec::new();
 381        let mut edits = edits.into_iter().peekable();
 382
 383        while let Some(edit) = edits.next() {
 384            // Preserve any old transforms that precede this edit.
 385            let old_start = WrapRow(edit.old.start);
 386            let new_start = WrapRow(edit.new.start);
 387            new_transforms.append(cursor.slice(&old_start, Bias::Left, &()), &());
 388            if let Some(transform) = cursor.item() {
 389                if transform.is_isomorphic() && old_start == cursor.end(&()) {
 390                    new_transforms.push(transform.clone(), &());
 391                    cursor.next(&());
 392                    while let Some(transform) = cursor.item() {
 393                        if transform
 394                            .block
 395                            .as_ref()
 396                            .map_or(false, |b| b.disposition().is_below())
 397                        {
 398                            new_transforms.push(transform.clone(), &());
 399                            cursor.next(&());
 400                        } else {
 401                            break;
 402                        }
 403                    }
 404                }
 405            }
 406
 407            // Preserve any portion of an old transform that precedes this edit.
 408            let extent_before_edit = old_start.0 - cursor.start().0;
 409            push_isomorphic(&mut new_transforms, extent_before_edit);
 410
 411            // Skip over any old transforms that intersect this edit.
 412            let mut old_end = WrapRow(edit.old.end);
 413            let mut new_end = WrapRow(edit.new.end);
 414            cursor.seek(&old_end, Bias::Left, &());
 415            cursor.next(&());
 416            if old_end == *cursor.start() {
 417                while let Some(transform) = cursor.item() {
 418                    if transform
 419                        .block
 420                        .as_ref()
 421                        .map_or(false, |b| b.disposition().is_below())
 422                    {
 423                        cursor.next(&());
 424                    } else {
 425                        break;
 426                    }
 427                }
 428            }
 429
 430            // Combine this edit with any subsequent edits that intersect the same transform.
 431            while let Some(next_edit) = edits.peek() {
 432                if next_edit.old.start <= cursor.start().0 {
 433                    old_end = WrapRow(next_edit.old.end);
 434                    new_end = WrapRow(next_edit.new.end);
 435                    cursor.seek(&old_end, Bias::Left, &());
 436                    cursor.next(&());
 437                    if old_end == *cursor.start() {
 438                        while let Some(transform) = cursor.item() {
 439                            if transform
 440                                .block
 441                                .as_ref()
 442                                .map_or(false, |b| b.disposition().is_below())
 443                            {
 444                                cursor.next(&());
 445                            } else {
 446                                break;
 447                            }
 448                        }
 449                    }
 450                    edits.next();
 451                } else {
 452                    break;
 453                }
 454            }
 455
 456            // Find the blocks within this edited region.
 457            let new_buffer_start =
 458                wrap_snapshot.to_point(WrapPoint::new(new_start.0, 0), Bias::Left);
 459            let start_bound = Bound::Included(new_buffer_start);
 460            let start_block_ix =
 461                match self.custom_blocks[last_block_ix..].binary_search_by(|probe| {
 462                    probe
 463                        .position
 464                        .to_point(buffer)
 465                        .cmp(&new_buffer_start)
 466                        .then(Ordering::Greater)
 467                }) {
 468                    Ok(ix) | Err(ix) => last_block_ix + ix,
 469                };
 470
 471            let end_bound;
 472            let end_block_ix = if new_end.0 > wrap_snapshot.max_point().row() {
 473                end_bound = Bound::Unbounded;
 474                self.custom_blocks.len()
 475            } else {
 476                let new_buffer_end =
 477                    wrap_snapshot.to_point(WrapPoint::new(new_end.0, 0), Bias::Left);
 478                end_bound = Bound::Excluded(new_buffer_end);
 479                match self.custom_blocks[start_block_ix..].binary_search_by(|probe| {
 480                    probe
 481                        .position
 482                        .to_point(buffer)
 483                        .cmp(&new_buffer_end)
 484                        .then(Ordering::Greater)
 485                }) {
 486                    Ok(ix) | Err(ix) => start_block_ix + ix,
 487                }
 488            };
 489            last_block_ix = end_block_ix;
 490
 491            debug_assert!(blocks_in_edit.is_empty());
 492            blocks_in_edit.extend(self.custom_blocks[start_block_ix..end_block_ix].iter().map(
 493                |block| {
 494                    let mut position = block.position.to_point(buffer);
 495                    match block.disposition {
 496                        BlockDisposition::Above => position.column = 0,
 497                        BlockDisposition::Below => {
 498                            position.column = buffer.line_len(MultiBufferRow(position.row))
 499                        }
 500                    }
 501                    let position = wrap_snapshot.make_wrap_point(position, Bias::Left);
 502                    (position.row(), Block::Custom(block.clone()))
 503                },
 504            ));
 505
 506            if buffer.show_headers() {
 507                blocks_in_edit.extend(BlockMap::header_and_footer_blocks(
 508                    self.show_excerpt_controls,
 509                    self.excerpt_footer_height,
 510                    self.buffer_header_height,
 511                    self.excerpt_header_height,
 512                    buffer,
 513                    (start_bound, end_bound),
 514                    wrap_snapshot,
 515                ));
 516            }
 517
 518            BlockMap::sort_blocks(&mut blocks_in_edit);
 519
 520            // For each of these blocks, insert a new isomorphic transform preceding the block,
 521            // and then insert the block itself.
 522            for (block_row, block) in blocks_in_edit.drain(..) {
 523                let insertion_row = match block.disposition() {
 524                    BlockDisposition::Above => block_row,
 525                    BlockDisposition::Below => block_row + 1,
 526                };
 527                let extent_before_block = insertion_row - new_transforms.summary().input_rows;
 528                push_isomorphic(&mut new_transforms, extent_before_block);
 529                new_transforms.push(Transform::block(block), &());
 530            }
 531
 532            old_end = WrapRow(old_end.0.min(old_row_count));
 533            new_end = WrapRow(new_end.0.min(new_row_count));
 534
 535            // Insert an isomorphic transform after the final block.
 536            let extent_after_last_block = new_end.0 - new_transforms.summary().input_rows;
 537            push_isomorphic(&mut new_transforms, extent_after_last_block);
 538
 539            // Preserve any portion of the old transform after this edit.
 540            let extent_after_edit = cursor.start().0 - old_end.0;
 541            push_isomorphic(&mut new_transforms, extent_after_edit);
 542        }
 543
 544        new_transforms.append(cursor.suffix(&()), &());
 545        debug_assert_eq!(
 546            new_transforms.summary().input_rows,
 547            wrap_snapshot.max_point().row() + 1
 548        );
 549
 550        drop(cursor);
 551        *transforms = new_transforms;
 552    }
 553
 554    pub fn replace_renderers(&mut self, mut renderers: HashMap<CustomBlockId, RenderBlock>) {
 555        for block in &mut self.custom_blocks {
 556            if let Some(render) = renderers.remove(&block.id) {
 557                *block.render.lock() = render;
 558            }
 559        }
 560    }
 561
 562    pub fn show_excerpt_controls(&self) -> bool {
 563        self.show_excerpt_controls
 564    }
 565
 566    pub fn header_and_footer_blocks<'a, 'b: 'a, 'c: 'a + 'b, R, T>(
 567        show_excerpt_controls: bool,
 568        excerpt_footer_height: u8,
 569        buffer_header_height: u8,
 570        excerpt_header_height: u8,
 571        buffer: &'b multi_buffer::MultiBufferSnapshot,
 572        range: R,
 573        wrap_snapshot: &'c WrapSnapshot,
 574    ) -> impl Iterator<Item = (u32, Block)> + 'b
 575    where
 576        R: RangeBounds<T>,
 577        T: multi_buffer::ToOffset,
 578    {
 579        buffer
 580            .excerpt_boundaries_in_range(range)
 581            .flat_map(move |excerpt_boundary| {
 582                let mut wrap_row = wrap_snapshot
 583                    .make_wrap_point(Point::new(excerpt_boundary.row.0, 0), Bias::Left)
 584                    .row();
 585
 586                [
 587                    show_excerpt_controls
 588                        .then(|| {
 589                            let disposition;
 590                            if excerpt_boundary.next.is_some() {
 591                                disposition = BlockDisposition::Above;
 592                            } else {
 593                                wrap_row = wrap_snapshot
 594                                    .make_wrap_point(
 595                                        Point::new(
 596                                            excerpt_boundary.row.0,
 597                                            buffer.line_len(excerpt_boundary.row),
 598                                        ),
 599                                        Bias::Left,
 600                                    )
 601                                    .row();
 602                                disposition = BlockDisposition::Below;
 603                            }
 604
 605                            excerpt_boundary.prev.as_ref().map(|prev| {
 606                                (
 607                                    wrap_row,
 608                                    Block::ExcerptFooter {
 609                                        id: prev.id,
 610                                        height: excerpt_footer_height,
 611                                        disposition,
 612                                    },
 613                                )
 614                            })
 615                        })
 616                        .flatten(),
 617                    excerpt_boundary.next.map(|next| {
 618                        let starts_new_buffer = excerpt_boundary
 619                            .prev
 620                            .map_or(true, |prev| prev.buffer_id != next.buffer_id);
 621
 622                        (
 623                            wrap_row,
 624                            Block::ExcerptHeader {
 625                                id: next.id,
 626                                buffer: next.buffer,
 627                                range: next.range,
 628                                height: if starts_new_buffer {
 629                                    buffer_header_height
 630                                } else {
 631                                    excerpt_header_height
 632                                },
 633                                starts_new_buffer,
 634                                show_excerpt_controls,
 635                            },
 636                        )
 637                    }),
 638                ]
 639            })
 640            .flatten()
 641    }
 642
 643    pub(crate) fn sort_blocks<B: BlockLike>(blocks: &mut Vec<(u32, B)>) {
 644        // Place excerpt headers and footers above custom blocks on the same row
 645        blocks.sort_unstable_by(|(row_a, block_a), (row_b, block_b)| {
 646            row_a.cmp(row_b).then_with(|| {
 647                block_a
 648                    .disposition()
 649                    .cmp(&block_b.disposition())
 650                    .then_with(|| match ((block_a.block_type()), (block_b.block_type())) {
 651                        (BlockType::Footer, BlockType::Footer) => Ordering::Equal,
 652                        (BlockType::Footer, _) => Ordering::Less,
 653                        (_, BlockType::Footer) => Ordering::Greater,
 654                        (BlockType::Header, BlockType::Header) => Ordering::Equal,
 655                        (BlockType::Header, _) => Ordering::Less,
 656                        (_, BlockType::Header) => Ordering::Greater,
 657                        (BlockType::Custom(a_id), BlockType::Custom(b_id)) => a_id.cmp(&b_id),
 658                    })
 659            })
 660        });
 661    }
 662}
 663
 664fn push_isomorphic(tree: &mut SumTree<Transform>, rows: u32) {
 665    if rows == 0 {
 666        return;
 667    }
 668
 669    let mut extent = Some(rows);
 670    tree.update_last(
 671        |last_transform| {
 672            if last_transform.is_isomorphic() {
 673                let extent = extent.take().unwrap();
 674                last_transform.summary.input_rows += extent;
 675                last_transform.summary.output_rows += extent;
 676            }
 677        },
 678        &(),
 679    );
 680    if let Some(extent) = extent {
 681        tree.push(Transform::isomorphic(extent), &());
 682    }
 683}
 684
 685impl BlockPoint {
 686    pub fn new(row: u32, column: u32) -> Self {
 687        Self(Point::new(row, column))
 688    }
 689}
 690
 691impl Deref for BlockPoint {
 692    type Target = Point;
 693
 694    fn deref(&self) -> &Self::Target {
 695        &self.0
 696    }
 697}
 698
 699impl std::ops::DerefMut for BlockPoint {
 700    fn deref_mut(&mut self) -> &mut Self::Target {
 701        &mut self.0
 702    }
 703}
 704
 705impl<'a> Deref for BlockMapReader<'a> {
 706    type Target = BlockSnapshot;
 707
 708    fn deref(&self) -> &Self::Target {
 709        &self.snapshot
 710    }
 711}
 712
 713impl<'a> DerefMut for BlockMapReader<'a> {
 714    fn deref_mut(&mut self) -> &mut Self::Target {
 715        &mut self.snapshot
 716    }
 717}
 718
 719impl<'a> BlockMapReader<'a> {
 720    pub fn row_for_block(&self, block_id: CustomBlockId) -> Option<BlockRow> {
 721        let block = self.blocks.iter().find(|block| block.id == block_id)?;
 722        let buffer_row = block
 723            .position
 724            .to_point(self.wrap_snapshot.buffer_snapshot())
 725            .row;
 726        let wrap_row = self
 727            .wrap_snapshot
 728            .make_wrap_point(Point::new(buffer_row, 0), Bias::Left)
 729            .row();
 730        let start_wrap_row = WrapRow(
 731            self.wrap_snapshot
 732                .prev_row_boundary(WrapPoint::new(wrap_row, 0)),
 733        );
 734        let end_wrap_row = WrapRow(
 735            self.wrap_snapshot
 736                .next_row_boundary(WrapPoint::new(wrap_row, 0))
 737                .unwrap_or(self.wrap_snapshot.max_point().row() + 1),
 738        );
 739
 740        let mut cursor = self.transforms.cursor::<(WrapRow, BlockRow)>();
 741        cursor.seek(&start_wrap_row, Bias::Left, &());
 742        while let Some(transform) = cursor.item() {
 743            if cursor.start().0 > end_wrap_row {
 744                break;
 745            }
 746
 747            if let Some(BlockType::Custom(id)) =
 748                transform.block.as_ref().map(|block| block.block_type())
 749            {
 750                if id == block_id {
 751                    return Some(cursor.start().1);
 752                }
 753            }
 754            cursor.next(&());
 755        }
 756
 757        None
 758    }
 759}
 760
 761impl<'a> BlockMapWriter<'a> {
 762    pub fn insert(
 763        &mut self,
 764        blocks: impl IntoIterator<Item = BlockProperties<Anchor>>,
 765    ) -> Vec<CustomBlockId> {
 766        let mut ids = Vec::new();
 767        let mut edits = Patch::default();
 768        let wrap_snapshot = &*self.0.wrap_snapshot.borrow();
 769        let buffer = wrap_snapshot.buffer_snapshot();
 770
 771        for block in blocks {
 772            let id = CustomBlockId(self.0.next_block_id.fetch_add(1, SeqCst));
 773            ids.push(id);
 774
 775            let position = block.position;
 776            let point = position.to_point(buffer);
 777            let wrap_row = wrap_snapshot
 778                .make_wrap_point(Point::new(point.row, 0), Bias::Left)
 779                .row();
 780            let start_row = wrap_snapshot.prev_row_boundary(WrapPoint::new(wrap_row, 0));
 781            let end_row = wrap_snapshot
 782                .next_row_boundary(WrapPoint::new(wrap_row, 0))
 783                .unwrap_or(wrap_snapshot.max_point().row() + 1);
 784
 785            let block_ix = match self
 786                .0
 787                .custom_blocks
 788                .binary_search_by(|probe| probe.position.cmp(&position, buffer))
 789            {
 790                Ok(ix) | Err(ix) => ix,
 791            };
 792            let new_block = Arc::new(CustomBlock {
 793                id,
 794                position,
 795                height: block.height,
 796                render: Mutex::new(block.render),
 797                disposition: block.disposition,
 798                style: block.style,
 799            });
 800            self.0.custom_blocks.insert(block_ix, new_block.clone());
 801            self.0.custom_blocks_by_id.insert(id, new_block);
 802
 803            edits = edits.compose([Edit {
 804                old: start_row..end_row,
 805                new: start_row..end_row,
 806            }]);
 807        }
 808
 809        self.0.sync(wrap_snapshot, edits);
 810        ids
 811    }
 812
 813    pub fn replace(
 814        &mut self,
 815        mut heights_and_renderers: HashMap<CustomBlockId, (u8, RenderBlock)>,
 816    ) {
 817        let wrap_snapshot = &*self.0.wrap_snapshot.borrow();
 818        let buffer = wrap_snapshot.buffer_snapshot();
 819        let mut edits = Patch::default();
 820        let mut last_block_buffer_row = None;
 821
 822        for block in &mut self.0.custom_blocks {
 823            if let Some((new_height, render)) = heights_and_renderers.remove(&block.id) {
 824                if block.height != new_height {
 825                    let new_block = CustomBlock {
 826                        id: block.id,
 827                        position: block.position,
 828                        height: new_height,
 829                        style: block.style,
 830                        render: Mutex::new(render),
 831                        disposition: block.disposition,
 832                    };
 833                    let new_block = Arc::new(new_block);
 834                    *block = new_block.clone();
 835                    self.0.custom_blocks_by_id.insert(block.id, new_block);
 836
 837                    let buffer_row = block.position.to_point(buffer).row;
 838                    if last_block_buffer_row != Some(buffer_row) {
 839                        last_block_buffer_row = Some(buffer_row);
 840                        let wrap_row = wrap_snapshot
 841                            .make_wrap_point(Point::new(buffer_row, 0), Bias::Left)
 842                            .row();
 843                        let start_row =
 844                            wrap_snapshot.prev_row_boundary(WrapPoint::new(wrap_row, 0));
 845                        let end_row = wrap_snapshot
 846                            .next_row_boundary(WrapPoint::new(wrap_row, 0))
 847                            .unwrap_or(wrap_snapshot.max_point().row() + 1);
 848                        edits.push(Edit {
 849                            old: start_row..end_row,
 850                            new: start_row..end_row,
 851                        })
 852                    }
 853                }
 854            }
 855        }
 856
 857        self.0.sync(wrap_snapshot, edits);
 858    }
 859
 860    pub fn remove(&mut self, block_ids: HashSet<CustomBlockId>) {
 861        let wrap_snapshot = &*self.0.wrap_snapshot.borrow();
 862        let buffer = wrap_snapshot.buffer_snapshot();
 863        let mut edits = Patch::default();
 864        let mut last_block_buffer_row = None;
 865        self.0.custom_blocks.retain(|block| {
 866            if block_ids.contains(&block.id) {
 867                let buffer_row = block.position.to_point(buffer).row;
 868                if last_block_buffer_row != Some(buffer_row) {
 869                    last_block_buffer_row = Some(buffer_row);
 870                    let wrap_row = wrap_snapshot
 871                        .make_wrap_point(Point::new(buffer_row, 0), Bias::Left)
 872                        .row();
 873                    let start_row = wrap_snapshot.prev_row_boundary(WrapPoint::new(wrap_row, 0));
 874                    let end_row = wrap_snapshot
 875                        .next_row_boundary(WrapPoint::new(wrap_row, 0))
 876                        .unwrap_or(wrap_snapshot.max_point().row() + 1);
 877                    edits.push(Edit {
 878                        old: start_row..end_row,
 879                        new: start_row..end_row,
 880                    })
 881                }
 882                self.0.custom_blocks_by_id.remove(&block.id);
 883                false
 884            } else {
 885                true
 886            }
 887        });
 888        self.0.sync(wrap_snapshot, edits);
 889    }
 890}
 891
 892impl BlockSnapshot {
 893    #[cfg(test)]
 894    pub fn text(&self) -> String {
 895        self.chunks(
 896            0..self.transforms.summary().output_rows,
 897            false,
 898            false,
 899            Highlights::default(),
 900        )
 901        .map(|chunk| chunk.text)
 902        .collect()
 903    }
 904
 905    pub(crate) fn chunks<'a>(
 906        &'a self,
 907        rows: Range<u32>,
 908        language_aware: bool,
 909        masked: bool,
 910        highlights: Highlights<'a>,
 911    ) -> BlockChunks<'a> {
 912        let max_output_row = cmp::min(rows.end, self.transforms.summary().output_rows);
 913        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 914        let input_end = {
 915            cursor.seek(&BlockRow(rows.end), Bias::Right, &());
 916            let overshoot = if cursor
 917                .item()
 918                .map_or(false, |transform| transform.is_isomorphic())
 919            {
 920                rows.end - cursor.start().0 .0
 921            } else {
 922                0
 923            };
 924            cursor.start().1 .0 + overshoot
 925        };
 926        let input_start = {
 927            cursor.seek(&BlockRow(rows.start), Bias::Right, &());
 928            let overshoot = if cursor
 929                .item()
 930                .map_or(false, |transform| transform.is_isomorphic())
 931            {
 932                rows.start - cursor.start().0 .0
 933            } else {
 934                0
 935            };
 936            cursor.start().1 .0 + overshoot
 937        };
 938        BlockChunks {
 939            input_chunks: self.wrap_snapshot.chunks(
 940                input_start..input_end,
 941                language_aware,
 942                highlights,
 943            ),
 944            input_chunk: Default::default(),
 945            transforms: cursor,
 946            output_row: rows.start,
 947            max_output_row,
 948            masked,
 949        }
 950    }
 951
 952    pub(super) fn buffer_rows(&self, start_row: BlockRow) -> BlockBufferRows {
 953        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 954        cursor.seek(&start_row, Bias::Right, &());
 955        let (output_start, input_start) = cursor.start();
 956        let overshoot = if cursor.item().map_or(false, |t| t.is_isomorphic()) {
 957            start_row.0 - output_start.0
 958        } else {
 959            0
 960        };
 961        let input_start_row = input_start.0 + overshoot;
 962        BlockBufferRows {
 963            transforms: cursor,
 964            input_buffer_rows: self.wrap_snapshot.buffer_rows(input_start_row),
 965            output_row: start_row,
 966            started: false,
 967        }
 968    }
 969
 970    pub fn blocks_in_range(&self, rows: Range<u32>) -> impl Iterator<Item = (u32, &Block)> {
 971        let mut cursor = self.transforms.cursor::<BlockRow>();
 972        cursor.seek(&BlockRow(rows.start), Bias::Right, &());
 973        std::iter::from_fn(move || {
 974            while let Some(transform) = cursor.item() {
 975                let start_row = cursor.start().0;
 976                if start_row >= rows.end {
 977                    break;
 978                }
 979                if let Some(block) = &transform.block {
 980                    cursor.next(&());
 981                    return Some((start_row, block));
 982                } else {
 983                    cursor.next(&());
 984                }
 985            }
 986            None
 987        })
 988    }
 989
 990    pub fn block_for_id(&self, block_id: BlockId) -> Option<Block> {
 991        let buffer = self.wrap_snapshot.buffer_snapshot();
 992
 993        match block_id {
 994            BlockId::Custom(custom_block_id) => {
 995                let custom_block = self.custom_blocks_by_id.get(&custom_block_id)?;
 996                Some(Block::Custom(custom_block.clone()))
 997            }
 998            BlockId::ExcerptHeader(excerpt_id) => {
 999                let excerpt_range = buffer.range_for_excerpt::<Point>(excerpt_id)?;
1000                let wrap_point = self
1001                    .wrap_snapshot
1002                    .make_wrap_point(excerpt_range.start, Bias::Left);
1003                let mut cursor = self.transforms.cursor::<(WrapRow, BlockRow)>();
1004                cursor.seek(&WrapRow(wrap_point.row()), Bias::Left, &());
1005                while let Some(transform) = cursor.item() {
1006                    if let Some(block) = transform.block.as_ref() {
1007                        if block.id() == block_id {
1008                            return Some(block.clone());
1009                        }
1010                    } else if cursor.start().0 > WrapRow(wrap_point.row()) {
1011                        break;
1012                    }
1013
1014                    cursor.next(&());
1015                }
1016
1017                None
1018            }
1019            BlockId::ExcerptFooter(excerpt_id) => {
1020                let excerpt_range = buffer.range_for_excerpt::<Point>(excerpt_id)?;
1021                let wrap_point = self
1022                    .wrap_snapshot
1023                    .make_wrap_point(excerpt_range.end, Bias::Left);
1024
1025                let mut cursor = self.transforms.cursor::<(WrapRow, BlockRow)>();
1026                cursor.seek(&WrapRow(wrap_point.row()), Bias::Left, &());
1027                while let Some(transform) = cursor.item() {
1028                    if let Some(block) = transform.block.as_ref() {
1029                        if block.id() == block_id {
1030                            return Some(block.clone());
1031                        }
1032                    } else if cursor.start().0 > WrapRow(wrap_point.row()) {
1033                        break;
1034                    }
1035
1036                    cursor.next(&());
1037                }
1038
1039                None
1040            }
1041        }
1042    }
1043
1044    pub fn max_point(&self) -> BlockPoint {
1045        let row = self.transforms.summary().output_rows - 1;
1046        BlockPoint::new(row, self.line_len(BlockRow(row)))
1047    }
1048
1049    pub fn longest_row(&self) -> u32 {
1050        let input_row = self.wrap_snapshot.longest_row();
1051        self.to_block_point(WrapPoint::new(input_row, 0)).row
1052    }
1053
1054    pub(super) fn line_len(&self, row: BlockRow) -> u32 {
1055        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
1056        cursor.seek(&BlockRow(row.0), Bias::Right, &());
1057        if let Some(transform) = cursor.item() {
1058            let (output_start, input_start) = cursor.start();
1059            let overshoot = row.0 - output_start.0;
1060            if transform.block.is_some() {
1061                0
1062            } else {
1063                self.wrap_snapshot.line_len(input_start.0 + overshoot)
1064            }
1065        } else {
1066            panic!("row out of range");
1067        }
1068    }
1069
1070    pub(super) fn is_block_line(&self, row: BlockRow) -> bool {
1071        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
1072        cursor.seek(&row, Bias::Right, &());
1073        cursor.item().map_or(false, |t| t.block.is_some())
1074    }
1075
1076    pub fn clip_point(&self, point: BlockPoint, bias: Bias) -> BlockPoint {
1077        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
1078        cursor.seek(&BlockRow(point.row), Bias::Right, &());
1079
1080        let max_input_row = WrapRow(self.transforms.summary().input_rows);
1081        let mut search_left =
1082            (bias == Bias::Left && cursor.start().1 .0 > 0) || cursor.end(&()).1 == max_input_row;
1083        let mut reversed = false;
1084
1085        loop {
1086            if let Some(transform) = cursor.item() {
1087                if transform.is_isomorphic() {
1088                    let (output_start_row, input_start_row) = cursor.start();
1089                    let (output_end_row, input_end_row) = cursor.end(&());
1090                    let output_start = Point::new(output_start_row.0, 0);
1091                    let input_start = Point::new(input_start_row.0, 0);
1092                    let input_end = Point::new(input_end_row.0, 0);
1093                    let input_point = if point.row >= output_end_row.0 {
1094                        let line_len = self.wrap_snapshot.line_len(input_end_row.0 - 1);
1095                        self.wrap_snapshot
1096                            .clip_point(WrapPoint::new(input_end_row.0 - 1, line_len), bias)
1097                    } else {
1098                        let output_overshoot = point.0.saturating_sub(output_start);
1099                        self.wrap_snapshot
1100                            .clip_point(WrapPoint(input_start + output_overshoot), bias)
1101                    };
1102
1103                    if (input_start..input_end).contains(&input_point.0) {
1104                        let input_overshoot = input_point.0.saturating_sub(input_start);
1105                        return BlockPoint(output_start + input_overshoot);
1106                    }
1107                }
1108
1109                if search_left {
1110                    cursor.prev(&());
1111                } else {
1112                    cursor.next(&());
1113                }
1114            } else if reversed {
1115                return self.max_point();
1116            } else {
1117                reversed = true;
1118                search_left = !search_left;
1119                cursor.seek(&BlockRow(point.row), Bias::Right, &());
1120            }
1121        }
1122    }
1123
1124    pub fn to_block_point(&self, wrap_point: WrapPoint) -> BlockPoint {
1125        let mut cursor = self.transforms.cursor::<(WrapRow, BlockRow)>();
1126        cursor.seek(&WrapRow(wrap_point.row()), Bias::Right, &());
1127        if let Some(transform) = cursor.item() {
1128            debug_assert!(transform.is_isomorphic());
1129        } else {
1130            return self.max_point();
1131        }
1132
1133        let (input_start_row, output_start_row) = cursor.start();
1134        let input_start = Point::new(input_start_row.0, 0);
1135        let output_start = Point::new(output_start_row.0, 0);
1136        let input_overshoot = wrap_point.0 - input_start;
1137        BlockPoint(output_start + input_overshoot)
1138    }
1139
1140    pub fn to_wrap_point(&self, block_point: BlockPoint) -> WrapPoint {
1141        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
1142        cursor.seek(&BlockRow(block_point.row), Bias::Right, &());
1143        if let Some(transform) = cursor.item() {
1144            match transform.block.as_ref().map(|b| b.disposition()) {
1145                Some(BlockDisposition::Above) => WrapPoint::new(cursor.start().1 .0, 0),
1146                Some(BlockDisposition::Below) => {
1147                    let wrap_row = cursor.start().1 .0 - 1;
1148                    WrapPoint::new(wrap_row, self.wrap_snapshot.line_len(wrap_row))
1149                }
1150                None => {
1151                    let overshoot = block_point.row - cursor.start().0 .0;
1152                    let wrap_row = cursor.start().1 .0 + overshoot;
1153                    WrapPoint::new(wrap_row, block_point.column)
1154                }
1155            }
1156        } else {
1157            self.wrap_snapshot.max_point()
1158        }
1159    }
1160}
1161
1162impl Transform {
1163    fn isomorphic(rows: u32) -> Self {
1164        Self {
1165            summary: TransformSummary {
1166                input_rows: rows,
1167                output_rows: rows,
1168            },
1169            block: None,
1170        }
1171    }
1172
1173    fn block(block: Block) -> Self {
1174        Self {
1175            summary: TransformSummary {
1176                input_rows: 0,
1177                output_rows: block.height() as u32,
1178            },
1179            block: Some(block),
1180        }
1181    }
1182
1183    fn is_isomorphic(&self) -> bool {
1184        self.block.is_none()
1185    }
1186}
1187
1188impl<'a> Iterator for BlockChunks<'a> {
1189    type Item = Chunk<'a>;
1190
1191    fn next(&mut self) -> Option<Self::Item> {
1192        if self.output_row >= self.max_output_row {
1193            return None;
1194        }
1195
1196        let transform = self.transforms.item()?;
1197        if transform.block.is_some() {
1198            let block_start = self.transforms.start().0 .0;
1199            let mut block_end = self.transforms.end(&()).0 .0;
1200            self.transforms.next(&());
1201            if self.transforms.item().is_none() {
1202                block_end -= 1;
1203            }
1204
1205            let start_in_block = self.output_row - block_start;
1206            let end_in_block = cmp::min(self.max_output_row, block_end) - block_start;
1207            let line_count = end_in_block - start_in_block;
1208            self.output_row += line_count;
1209
1210            return Some(Chunk {
1211                text: unsafe { std::str::from_utf8_unchecked(&NEWLINES[..line_count as usize]) },
1212                ..Default::default()
1213            });
1214        }
1215
1216        if self.input_chunk.text.is_empty() {
1217            if let Some(input_chunk) = self.input_chunks.next() {
1218                self.input_chunk = input_chunk;
1219            } else {
1220                self.output_row += 1;
1221                if self.output_row < self.max_output_row {
1222                    self.transforms.next(&());
1223                    return Some(Chunk {
1224                        text: "\n",
1225                        ..Default::default()
1226                    });
1227                } else {
1228                    return None;
1229                }
1230            }
1231        }
1232
1233        let transform_end = self.transforms.end(&()).0 .0;
1234        let (prefix_rows, prefix_bytes) =
1235            offset_for_row(self.input_chunk.text, transform_end - self.output_row);
1236        self.output_row += prefix_rows;
1237        let (mut prefix, suffix) = self.input_chunk.text.split_at(prefix_bytes);
1238        self.input_chunk.text = suffix;
1239        if self.output_row == transform_end {
1240            self.transforms.next(&());
1241        }
1242
1243        if self.masked {
1244            // Not great for multibyte text because to keep cursor math correct we
1245            // need to have the same number of bytes in the input as output.
1246            let chars = prefix.chars().count();
1247            let bullet_len = chars;
1248            prefix = &BULLETS[..bullet_len];
1249        }
1250
1251        Some(Chunk {
1252            text: prefix,
1253            ..self.input_chunk.clone()
1254        })
1255    }
1256}
1257
1258impl<'a> Iterator for BlockBufferRows<'a> {
1259    type Item = Option<BlockRow>;
1260
1261    fn next(&mut self) -> Option<Self::Item> {
1262        if self.started {
1263            self.output_row.0 += 1;
1264        } else {
1265            self.started = true;
1266        }
1267
1268        if self.output_row.0 >= self.transforms.end(&()).0 .0 {
1269            self.transforms.next(&());
1270        }
1271
1272        let transform = self.transforms.item()?;
1273        if transform.block.is_some() {
1274            Some(None)
1275        } else {
1276            Some(self.input_buffer_rows.next().unwrap().map(BlockRow))
1277        }
1278    }
1279}
1280
1281impl sum_tree::Item for Transform {
1282    type Summary = TransformSummary;
1283
1284    fn summary(&self) -> Self::Summary {
1285        self.summary.clone()
1286    }
1287}
1288
1289impl sum_tree::Summary for TransformSummary {
1290    type Context = ();
1291
1292    fn add_summary(&mut self, summary: &Self, _: &()) {
1293        self.input_rows += summary.input_rows;
1294        self.output_rows += summary.output_rows;
1295    }
1296}
1297
1298impl<'a> sum_tree::Dimension<'a, TransformSummary> for WrapRow {
1299    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1300        self.0 += summary.input_rows;
1301    }
1302}
1303
1304impl<'a> sum_tree::Dimension<'a, TransformSummary> for BlockRow {
1305    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
1306        self.0 += summary.output_rows;
1307    }
1308}
1309
1310impl BlockDisposition {
1311    fn is_below(&self) -> bool {
1312        matches!(self, BlockDisposition::Below)
1313    }
1314}
1315
1316impl<'a> Deref for BlockContext<'a, '_> {
1317    type Target = WindowContext<'a>;
1318
1319    fn deref(&self) -> &Self::Target {
1320        self.context
1321    }
1322}
1323
1324impl DerefMut for BlockContext<'_, '_> {
1325    fn deref_mut(&mut self) -> &mut Self::Target {
1326        self.context
1327    }
1328}
1329
1330impl CustomBlock {
1331    pub fn render(&self, cx: &mut BlockContext) -> AnyElement {
1332        self.render.lock()(cx)
1333    }
1334
1335    pub fn position(&self) -> &Anchor {
1336        &self.position
1337    }
1338
1339    pub fn style(&self) -> BlockStyle {
1340        self.style
1341    }
1342}
1343
1344impl Debug for CustomBlock {
1345    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
1346        f.debug_struct("Block")
1347            .field("id", &self.id)
1348            .field("position", &self.position)
1349            .field("disposition", &self.disposition)
1350            .finish()
1351    }
1352}
1353
1354// Count the number of bytes prior to a target point. If the string doesn't contain the target
1355// point, return its total extent. Otherwise return the target point itself.
1356fn offset_for_row(s: &str, target: u32) -> (u32, usize) {
1357    let mut row = 0;
1358    let mut offset = 0;
1359    for (ix, line) in s.split('\n').enumerate() {
1360        if ix > 0 {
1361            row += 1;
1362            offset += 1;
1363        }
1364        if row >= target {
1365            break;
1366        }
1367        offset += line.len();
1368    }
1369    (row, offset)
1370}
1371
1372#[cfg(test)]
1373mod tests {
1374    use super::*;
1375    use crate::display_map::{
1376        fold_map::FoldMap, inlay_map::InlayMap, tab_map::TabMap, wrap_map::WrapMap,
1377    };
1378    use gpui::{div, font, px, AppContext, Context as _, Element};
1379    use language::{Buffer, Capability};
1380    use multi_buffer::MultiBuffer;
1381    use rand::prelude::*;
1382    use settings::SettingsStore;
1383    use std::env;
1384    use util::RandomCharIter;
1385
1386    #[gpui::test]
1387    fn test_offset_for_row() {
1388        assert_eq!(offset_for_row("", 0), (0, 0));
1389        assert_eq!(offset_for_row("", 1), (0, 0));
1390        assert_eq!(offset_for_row("abcd", 0), (0, 0));
1391        assert_eq!(offset_for_row("abcd", 1), (0, 4));
1392        assert_eq!(offset_for_row("\n", 0), (0, 0));
1393        assert_eq!(offset_for_row("\n", 1), (1, 1));
1394        assert_eq!(offset_for_row("abc\ndef\nghi", 0), (0, 0));
1395        assert_eq!(offset_for_row("abc\ndef\nghi", 1), (1, 4));
1396        assert_eq!(offset_for_row("abc\ndef\nghi", 2), (2, 8));
1397        assert_eq!(offset_for_row("abc\ndef\nghi", 3), (2, 11));
1398    }
1399
1400    #[gpui::test]
1401    fn test_basic_blocks(cx: &mut gpui::TestAppContext) {
1402        cx.update(|cx| init_test(cx));
1403
1404        let text = "aaa\nbbb\nccc\nddd";
1405
1406        let buffer = cx.update(|cx| MultiBuffer::build_simple(text, cx));
1407        let buffer_snapshot = cx.update(|cx| buffer.read(cx).snapshot(cx));
1408        let subscription = buffer.update(cx, |buffer, _| buffer.subscribe());
1409        let (mut inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
1410        let (mut fold_map, fold_snapshot) = FoldMap::new(inlay_snapshot);
1411        let (mut tab_map, tab_snapshot) = TabMap::new(fold_snapshot, 1.try_into().unwrap());
1412        let (wrap_map, wraps_snapshot) =
1413            cx.update(|cx| WrapMap::new(tab_snapshot, font("Helvetica"), px(14.0), None, cx));
1414        let mut block_map = BlockMap::new(wraps_snapshot.clone(), true, 1, 1, 1);
1415
1416        let mut writer = block_map.write(wraps_snapshot.clone(), Default::default());
1417        let block_ids = writer.insert(vec![
1418            BlockProperties {
1419                style: BlockStyle::Fixed,
1420                position: buffer_snapshot.anchor_after(Point::new(1, 0)),
1421                height: 1,
1422                disposition: BlockDisposition::Above,
1423                render: Box::new(|_| div().into_any()),
1424            },
1425            BlockProperties {
1426                style: BlockStyle::Fixed,
1427                position: buffer_snapshot.anchor_after(Point::new(1, 2)),
1428                height: 2,
1429                disposition: BlockDisposition::Above,
1430                render: Box::new(|_| div().into_any()),
1431            },
1432            BlockProperties {
1433                style: BlockStyle::Fixed,
1434                position: buffer_snapshot.anchor_after(Point::new(3, 3)),
1435                height: 3,
1436                disposition: BlockDisposition::Below,
1437                render: Box::new(|_| div().into_any()),
1438            },
1439        ]);
1440
1441        let snapshot = block_map.read(wraps_snapshot, Default::default());
1442        assert_eq!(snapshot.text(), "aaa\n\n\n\nbbb\nccc\nddd\n\n\n");
1443
1444        let blocks = snapshot
1445            .blocks_in_range(0..8)
1446            .map(|(start_row, block)| {
1447                let block = block.as_custom().unwrap();
1448                (start_row..start_row + block.height as u32, block.id)
1449            })
1450            .collect::<Vec<_>>();
1451
1452        // When multiple blocks are on the same line, the newer blocks appear first.
1453        assert_eq!(
1454            blocks,
1455            &[
1456                (1..2, block_ids[0]),
1457                (2..4, block_ids[1]),
1458                (7..10, block_ids[2]),
1459            ]
1460        );
1461
1462        assert_eq!(
1463            snapshot.to_block_point(WrapPoint::new(0, 3)),
1464            BlockPoint::new(0, 3)
1465        );
1466        assert_eq!(
1467            snapshot.to_block_point(WrapPoint::new(1, 0)),
1468            BlockPoint::new(4, 0)
1469        );
1470        assert_eq!(
1471            snapshot.to_block_point(WrapPoint::new(3, 3)),
1472            BlockPoint::new(6, 3)
1473        );
1474
1475        assert_eq!(
1476            snapshot.to_wrap_point(BlockPoint::new(0, 3)),
1477            WrapPoint::new(0, 3)
1478        );
1479        assert_eq!(
1480            snapshot.to_wrap_point(BlockPoint::new(1, 0)),
1481            WrapPoint::new(1, 0)
1482        );
1483        assert_eq!(
1484            snapshot.to_wrap_point(BlockPoint::new(3, 0)),
1485            WrapPoint::new(1, 0)
1486        );
1487        assert_eq!(
1488            snapshot.to_wrap_point(BlockPoint::new(7, 0)),
1489            WrapPoint::new(3, 3)
1490        );
1491
1492        assert_eq!(
1493            snapshot.clip_point(BlockPoint::new(1, 0), Bias::Left),
1494            BlockPoint::new(0, 3)
1495        );
1496        assert_eq!(
1497            snapshot.clip_point(BlockPoint::new(1, 0), Bias::Right),
1498            BlockPoint::new(4, 0)
1499        );
1500        assert_eq!(
1501            snapshot.clip_point(BlockPoint::new(1, 1), Bias::Left),
1502            BlockPoint::new(0, 3)
1503        );
1504        assert_eq!(
1505            snapshot.clip_point(BlockPoint::new(1, 1), Bias::Right),
1506            BlockPoint::new(4, 0)
1507        );
1508        assert_eq!(
1509            snapshot.clip_point(BlockPoint::new(4, 0), Bias::Left),
1510            BlockPoint::new(4, 0)
1511        );
1512        assert_eq!(
1513            snapshot.clip_point(BlockPoint::new(4, 0), Bias::Right),
1514            BlockPoint::new(4, 0)
1515        );
1516        assert_eq!(
1517            snapshot.clip_point(BlockPoint::new(6, 3), Bias::Left),
1518            BlockPoint::new(6, 3)
1519        );
1520        assert_eq!(
1521            snapshot.clip_point(BlockPoint::new(6, 3), Bias::Right),
1522            BlockPoint::new(6, 3)
1523        );
1524        assert_eq!(
1525            snapshot.clip_point(BlockPoint::new(7, 0), Bias::Left),
1526            BlockPoint::new(6, 3)
1527        );
1528        assert_eq!(
1529            snapshot.clip_point(BlockPoint::new(7, 0), Bias::Right),
1530            BlockPoint::new(6, 3)
1531        );
1532
1533        assert_eq!(
1534            snapshot
1535                .buffer_rows(BlockRow(0))
1536                .map(|row| row.map(|r| r.0))
1537                .collect::<Vec<_>>(),
1538            &[
1539                Some(0),
1540                None,
1541                None,
1542                None,
1543                Some(1),
1544                Some(2),
1545                Some(3),
1546                None,
1547                None,
1548                None
1549            ]
1550        );
1551
1552        // Insert a line break, separating two block decorations into separate lines.
1553        let buffer_snapshot = buffer.update(cx, |buffer, cx| {
1554            buffer.edit([(Point::new(1, 1)..Point::new(1, 1), "!!!\n")], None, cx);
1555            buffer.snapshot(cx)
1556        });
1557
1558        let (inlay_snapshot, inlay_edits) =
1559            inlay_map.sync(buffer_snapshot, subscription.consume().into_inner());
1560        let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1561        let (tab_snapshot, tab_edits) =
1562            tab_map.sync(fold_snapshot, fold_edits, 4.try_into().unwrap());
1563        let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1564            wrap_map.sync(tab_snapshot, tab_edits, cx)
1565        });
1566        let snapshot = block_map.read(wraps_snapshot, wrap_edits);
1567        assert_eq!(snapshot.text(), "aaa\n\nb!!!\n\n\nbb\nccc\nddd\n\n\n");
1568    }
1569
1570    #[gpui::test]
1571    fn test_multibuffer_headers_and_footers(cx: &mut AppContext) {
1572        init_test(cx);
1573
1574        let buffer1 = cx.new_model(|cx| Buffer::local("Buffer 1", cx));
1575        let buffer2 = cx.new_model(|cx| Buffer::local("Buffer 2", cx));
1576        let buffer3 = cx.new_model(|cx| Buffer::local("Buffer 3", cx));
1577
1578        let mut excerpt_ids = Vec::new();
1579        let multi_buffer = cx.new_model(|cx| {
1580            let mut multi_buffer = MultiBuffer::new(0, Capability::ReadWrite);
1581            excerpt_ids.extend(multi_buffer.push_excerpts(
1582                buffer1.clone(),
1583                [ExcerptRange {
1584                    context: 0..buffer1.read(cx).len(),
1585                    primary: None,
1586                }],
1587                cx,
1588            ));
1589            excerpt_ids.extend(multi_buffer.push_excerpts(
1590                buffer2.clone(),
1591                [ExcerptRange {
1592                    context: 0..buffer2.read(cx).len(),
1593                    primary: None,
1594                }],
1595                cx,
1596            ));
1597            excerpt_ids.extend(multi_buffer.push_excerpts(
1598                buffer3.clone(),
1599                [ExcerptRange {
1600                    context: 0..buffer3.read(cx).len(),
1601                    primary: None,
1602                }],
1603                cx,
1604            ));
1605
1606            multi_buffer
1607        });
1608
1609        let font = font("Helvetica");
1610        let font_size = px(14.);
1611        let font_id = cx.text_system().resolve_font(&font);
1612        let mut wrap_width = px(0.);
1613        for c in "Buff".chars() {
1614            wrap_width += cx
1615                .text_system()
1616                .advance(font_id, font_size, c)
1617                .unwrap()
1618                .width;
1619        }
1620
1621        let multi_buffer_snapshot = multi_buffer.read(cx).snapshot(cx);
1622        let (_, inlay_snapshot) = InlayMap::new(multi_buffer_snapshot.clone());
1623        let (_, fold_snapshot) = FoldMap::new(inlay_snapshot);
1624        let (_, tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
1625        let (_, wraps_snapshot) = WrapMap::new(tab_snapshot, font, font_size, Some(wrap_width), cx);
1626
1627        let block_map = BlockMap::new(wraps_snapshot.clone(), true, 1, 1, 1);
1628        let snapshot = block_map.read(wraps_snapshot, Default::default());
1629
1630        // Each excerpt has a header above and footer below. Excerpts are also *separated* by a newline.
1631        assert_eq!(
1632            snapshot.text(),
1633            "\nBuff\ner 1\n\n\nBuff\ner 2\n\n\nBuff\ner 3\n"
1634        );
1635
1636        let blocks: Vec<_> = snapshot
1637            .blocks_in_range(0..u32::MAX)
1638            .map(|(row, block)| (row, block.id()))
1639            .collect();
1640        assert_eq!(
1641            blocks,
1642            vec![
1643                (0, BlockId::ExcerptHeader(excerpt_ids[0])),
1644                (3, BlockId::ExcerptFooter(excerpt_ids[0])),
1645                (4, BlockId::ExcerptHeader(excerpt_ids[1])),
1646                (7, BlockId::ExcerptFooter(excerpt_ids[1])),
1647                (8, BlockId::ExcerptHeader(excerpt_ids[2])),
1648                (11, BlockId::ExcerptFooter(excerpt_ids[2]))
1649            ]
1650        );
1651    }
1652
1653    #[gpui::test]
1654    fn test_replace_with_heights(cx: &mut gpui::TestAppContext) {
1655        let _update = cx.update(|cx| init_test(cx));
1656
1657        let text = "aaa\nbbb\nccc\nddd";
1658
1659        let buffer = cx.update(|cx| MultiBuffer::build_simple(text, cx));
1660        let buffer_snapshot = cx.update(|cx| buffer.read(cx).snapshot(cx));
1661        let _subscription = buffer.update(cx, |buffer, _| buffer.subscribe());
1662        let (_inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
1663        let (_fold_map, fold_snapshot) = FoldMap::new(inlay_snapshot);
1664        let (_tab_map, tab_snapshot) = TabMap::new(fold_snapshot, 1.try_into().unwrap());
1665        let (_wrap_map, wraps_snapshot) =
1666            cx.update(|cx| WrapMap::new(tab_snapshot, font("Helvetica"), px(14.0), None, cx));
1667        let mut block_map = BlockMap::new(wraps_snapshot.clone(), false, 1, 1, 0);
1668
1669        let mut writer = block_map.write(wraps_snapshot.clone(), Default::default());
1670        let block_ids = writer.insert(vec![
1671            BlockProperties {
1672                style: BlockStyle::Fixed,
1673                position: buffer_snapshot.anchor_after(Point::new(1, 0)),
1674                height: 1,
1675                disposition: BlockDisposition::Above,
1676                render: Box::new(|_| div().into_any()),
1677            },
1678            BlockProperties {
1679                style: BlockStyle::Fixed,
1680                position: buffer_snapshot.anchor_after(Point::new(1, 2)),
1681                height: 2,
1682                disposition: BlockDisposition::Above,
1683                render: Box::new(|_| div().into_any()),
1684            },
1685            BlockProperties {
1686                style: BlockStyle::Fixed,
1687                position: buffer_snapshot.anchor_after(Point::new(3, 3)),
1688                height: 3,
1689                disposition: BlockDisposition::Below,
1690                render: Box::new(|_| div().into_any()),
1691            },
1692        ]);
1693
1694        {
1695            let snapshot = block_map.read(wraps_snapshot.clone(), Default::default());
1696            assert_eq!(snapshot.text(), "aaa\n\n\n\nbbb\nccc\nddd\n\n\n");
1697
1698            let mut block_map_writer = block_map.write(wraps_snapshot.clone(), Default::default());
1699
1700            let mut hash_map = HashMap::default();
1701            let render: RenderBlock = Box::new(|_| div().into_any());
1702            hash_map.insert(block_ids[0], (2_u8, render));
1703            block_map_writer.replace(hash_map);
1704            let snapshot = block_map.read(wraps_snapshot.clone(), Default::default());
1705            assert_eq!(snapshot.text(), "aaa\n\n\n\n\nbbb\nccc\nddd\n\n\n");
1706        }
1707
1708        {
1709            let mut block_map_writer = block_map.write(wraps_snapshot.clone(), Default::default());
1710
1711            let mut hash_map = HashMap::default();
1712            let render: RenderBlock = Box::new(|_| div().into_any());
1713            hash_map.insert(block_ids[0], (1_u8, render));
1714            block_map_writer.replace(hash_map);
1715
1716            let snapshot = block_map.read(wraps_snapshot.clone(), Default::default());
1717            assert_eq!(snapshot.text(), "aaa\n\n\n\nbbb\nccc\nddd\n\n\n");
1718        }
1719
1720        {
1721            let mut block_map_writer = block_map.write(wraps_snapshot.clone(), Default::default());
1722
1723            let mut hash_map = HashMap::default();
1724            let render: RenderBlock = Box::new(|_| div().into_any());
1725            hash_map.insert(block_ids[0], (0_u8, render));
1726            block_map_writer.replace(hash_map);
1727
1728            let snapshot = block_map.read(wraps_snapshot.clone(), Default::default());
1729            assert_eq!(snapshot.text(), "aaa\n\n\nbbb\nccc\nddd\n\n\n");
1730        }
1731
1732        {
1733            let mut block_map_writer = block_map.write(wraps_snapshot.clone(), Default::default());
1734
1735            let mut hash_map = HashMap::default();
1736            let render: RenderBlock = Box::new(|_| div().into_any());
1737            hash_map.insert(block_ids[0], (3_u8, render));
1738            block_map_writer.replace(hash_map);
1739
1740            let snapshot = block_map.read(wraps_snapshot.clone(), Default::default());
1741            assert_eq!(snapshot.text(), "aaa\n\n\n\n\n\nbbb\nccc\nddd\n\n\n");
1742        }
1743
1744        {
1745            let mut block_map_writer = block_map.write(wraps_snapshot.clone(), Default::default());
1746
1747            let mut hash_map = HashMap::default();
1748            let render: RenderBlock = Box::new(|_| div().into_any());
1749            hash_map.insert(block_ids[0], (3_u8, render));
1750            block_map_writer.replace(hash_map);
1751
1752            let snapshot = block_map.read(wraps_snapshot.clone(), Default::default());
1753            // Same height as before, should remain the same
1754            assert_eq!(snapshot.text(), "aaa\n\n\n\n\n\nbbb\nccc\nddd\n\n\n");
1755        }
1756    }
1757
1758    #[cfg(target_os = "macos")]
1759    #[gpui::test]
1760    fn test_blocks_on_wrapped_lines(cx: &mut gpui::TestAppContext) {
1761        cx.update(|cx| init_test(cx));
1762
1763        let _font_id = cx.text_system().font_id(&font("Helvetica")).unwrap();
1764
1765        let text = "one two three\nfour five six\nseven eight";
1766
1767        let buffer = cx.update(|cx| MultiBuffer::build_simple(text, cx));
1768        let buffer_snapshot = cx.update(|cx| buffer.read(cx).snapshot(cx));
1769        let (_, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
1770        let (_, fold_snapshot) = FoldMap::new(inlay_snapshot);
1771        let (_, tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
1772        let (_, wraps_snapshot) = cx.update(|cx| {
1773            WrapMap::new(tab_snapshot, font("Helvetica"), px(14.0), Some(px(60.)), cx)
1774        });
1775        let mut block_map = BlockMap::new(wraps_snapshot.clone(), true, 1, 1, 0);
1776
1777        let mut writer = block_map.write(wraps_snapshot.clone(), Default::default());
1778        writer.insert(vec![
1779            BlockProperties {
1780                style: BlockStyle::Fixed,
1781                position: buffer_snapshot.anchor_after(Point::new(1, 12)),
1782                disposition: BlockDisposition::Above,
1783                render: Box::new(|_| div().into_any()),
1784                height: 1,
1785            },
1786            BlockProperties {
1787                style: BlockStyle::Fixed,
1788                position: buffer_snapshot.anchor_after(Point::new(1, 1)),
1789                disposition: BlockDisposition::Below,
1790                render: Box::new(|_| div().into_any()),
1791                height: 1,
1792            },
1793        ]);
1794
1795        // Blocks with an 'above' disposition go above their corresponding buffer line.
1796        // Blocks with a 'below' disposition go below their corresponding buffer line.
1797        let snapshot = block_map.read(wraps_snapshot, Default::default());
1798        assert_eq!(
1799            snapshot.text(),
1800            "one two \nthree\n\nfour five \nsix\n\nseven \neight"
1801        );
1802    }
1803
1804    #[gpui::test(iterations = 100)]
1805    fn test_random_blocks(cx: &mut gpui::TestAppContext, mut rng: StdRng) {
1806        cx.update(|cx| init_test(cx));
1807
1808        let operations = env::var("OPERATIONS")
1809            .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
1810            .unwrap_or(10);
1811
1812        let wrap_width = if rng.gen_bool(0.2) {
1813            None
1814        } else {
1815            Some(px(rng.gen_range(0.0..=100.0)))
1816        };
1817        let tab_size = 1.try_into().unwrap();
1818        let font_size = px(14.0);
1819        let buffer_start_header_height = rng.gen_range(1..=5);
1820        let excerpt_header_height = rng.gen_range(1..=5);
1821        let excerpt_footer_height = rng.gen_range(1..=5);
1822
1823        log::info!("Wrap width: {:?}", wrap_width);
1824        log::info!("Excerpt Header Height: {:?}", excerpt_header_height);
1825        log::info!("Excerpt Footer Height: {:?}", excerpt_footer_height);
1826
1827        let buffer = if rng.gen() {
1828            let len = rng.gen_range(0..10);
1829            let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
1830            log::info!("initial buffer text: {:?}", text);
1831            cx.update(|cx| MultiBuffer::build_simple(&text, cx))
1832        } else {
1833            cx.update(|cx| MultiBuffer::build_random(&mut rng, cx))
1834        };
1835
1836        let mut buffer_snapshot = cx.update(|cx| buffer.read(cx).snapshot(cx));
1837        let (mut inlay_map, inlay_snapshot) = InlayMap::new(buffer_snapshot.clone());
1838        let (mut fold_map, fold_snapshot) = FoldMap::new(inlay_snapshot);
1839        let (mut tab_map, tab_snapshot) = TabMap::new(fold_snapshot, 4.try_into().unwrap());
1840        let (wrap_map, wraps_snapshot) = cx
1841            .update(|cx| WrapMap::new(tab_snapshot, font("Helvetica"), font_size, wrap_width, cx));
1842        let mut block_map = BlockMap::new(
1843            wraps_snapshot,
1844            true,
1845            buffer_start_header_height,
1846            excerpt_header_height,
1847            excerpt_footer_height,
1848        );
1849        let mut custom_blocks = Vec::new();
1850
1851        for _ in 0..operations {
1852            let mut buffer_edits = Vec::new();
1853            match rng.gen_range(0..=100) {
1854                0..=19 => {
1855                    let wrap_width = if rng.gen_bool(0.2) {
1856                        None
1857                    } else {
1858                        Some(px(rng.gen_range(0.0..=100.0)))
1859                    };
1860                    log::info!("Setting wrap width to {:?}", wrap_width);
1861                    wrap_map.update(cx, |map, cx| map.set_wrap_width(wrap_width, cx));
1862                }
1863                20..=39 => {
1864                    let block_count = rng.gen_range(1..=5);
1865                    let block_properties = (0..block_count)
1866                        .map(|_| {
1867                            let buffer = cx.update(|cx| buffer.read(cx).read(cx).clone());
1868                            let position = buffer.anchor_after(
1869                                buffer.clip_offset(rng.gen_range(0..=buffer.len()), Bias::Left),
1870                            );
1871
1872                            let disposition = if rng.gen() {
1873                                BlockDisposition::Above
1874                            } else {
1875                                BlockDisposition::Below
1876                            };
1877                            let height = rng.gen_range(1..5);
1878                            log::info!(
1879                                "inserting block {:?} {:?} with height {}",
1880                                disposition,
1881                                position.to_point(&buffer),
1882                                height
1883                            );
1884                            BlockProperties {
1885                                style: BlockStyle::Fixed,
1886                                position,
1887                                height,
1888                                disposition,
1889                                render: Box::new(|_| div().into_any()),
1890                            }
1891                        })
1892                        .collect::<Vec<_>>();
1893
1894                    let (inlay_snapshot, inlay_edits) =
1895                        inlay_map.sync(buffer_snapshot.clone(), vec![]);
1896                    let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1897                    let (tab_snapshot, tab_edits) =
1898                        tab_map.sync(fold_snapshot, fold_edits, tab_size);
1899                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1900                        wrap_map.sync(tab_snapshot, tab_edits, cx)
1901                    });
1902                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits);
1903                    let block_ids =
1904                        block_map.insert(block_properties.iter().map(|props| BlockProperties {
1905                            position: props.position,
1906                            height: props.height,
1907                            style: props.style,
1908                            render: Box::new(|_| div().into_any()),
1909                            disposition: props.disposition,
1910                        }));
1911                    for (block_id, props) in block_ids.into_iter().zip(block_properties) {
1912                        custom_blocks.push((block_id, props));
1913                    }
1914                }
1915                40..=59 if !custom_blocks.is_empty() => {
1916                    let block_count = rng.gen_range(1..=4.min(custom_blocks.len()));
1917                    let block_ids_to_remove = (0..block_count)
1918                        .map(|_| {
1919                            custom_blocks
1920                                .remove(rng.gen_range(0..custom_blocks.len()))
1921                                .0
1922                        })
1923                        .collect();
1924
1925                    let (inlay_snapshot, inlay_edits) =
1926                        inlay_map.sync(buffer_snapshot.clone(), vec![]);
1927                    let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1928                    let (tab_snapshot, tab_edits) =
1929                        tab_map.sync(fold_snapshot, fold_edits, tab_size);
1930                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1931                        wrap_map.sync(tab_snapshot, tab_edits, cx)
1932                    });
1933                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits);
1934                    block_map.remove(block_ids_to_remove);
1935                }
1936                _ => {
1937                    buffer.update(cx, |buffer, cx| {
1938                        let mutation_count = rng.gen_range(1..=5);
1939                        let subscription = buffer.subscribe();
1940                        buffer.randomly_mutate(&mut rng, mutation_count, cx);
1941                        buffer_snapshot = buffer.snapshot(cx);
1942                        buffer_edits.extend(subscription.consume());
1943                        log::info!("buffer text: {:?}", buffer_snapshot.text());
1944                    });
1945                }
1946            }
1947
1948            let (inlay_snapshot, inlay_edits) =
1949                inlay_map.sync(buffer_snapshot.clone(), buffer_edits);
1950            let (fold_snapshot, fold_edits) = fold_map.read(inlay_snapshot, inlay_edits);
1951            let (tab_snapshot, tab_edits) = tab_map.sync(fold_snapshot, fold_edits, tab_size);
1952            let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1953                wrap_map.sync(tab_snapshot, tab_edits, cx)
1954            });
1955            let blocks_snapshot = block_map.read(wraps_snapshot.clone(), wrap_edits);
1956            assert_eq!(
1957                blocks_snapshot.transforms.summary().input_rows,
1958                wraps_snapshot.max_point().row() + 1
1959            );
1960            log::info!("blocks text: {:?}", blocks_snapshot.text());
1961
1962            let mut expected_blocks = Vec::new();
1963            expected_blocks.extend(custom_blocks.iter().map(|(id, block)| {
1964                let mut position = block.position.to_point(&buffer_snapshot);
1965                match block.disposition {
1966                    BlockDisposition::Above => {
1967                        position.column = 0;
1968                    }
1969                    BlockDisposition::Below => {
1970                        position.column = buffer_snapshot.line_len(MultiBufferRow(position.row));
1971                    }
1972                };
1973                let row = wraps_snapshot.make_wrap_point(position, Bias::Left).row();
1974                (
1975                    row,
1976                    ExpectedBlock::Custom {
1977                        disposition: block.disposition,
1978                        id: *id,
1979                        height: block.height,
1980                    },
1981                )
1982            }));
1983
1984            // Note that this needs to be synced with the related section in BlockMap::sync
1985            expected_blocks.extend(
1986                BlockMap::header_and_footer_blocks(
1987                    true,
1988                    excerpt_footer_height,
1989                    buffer_start_header_height,
1990                    excerpt_header_height,
1991                    &buffer_snapshot,
1992                    0..,
1993                    &wraps_snapshot,
1994                )
1995                .map(|(row, block)| (row, block.into())),
1996            );
1997
1998            BlockMap::sort_blocks(&mut expected_blocks);
1999
2000            let mut sorted_blocks_iter = expected_blocks.into_iter().peekable();
2001
2002            let input_buffer_rows = buffer_snapshot
2003                .buffer_rows(MultiBufferRow(0))
2004                .collect::<Vec<_>>();
2005            let mut expected_buffer_rows = Vec::new();
2006            let mut expected_text = String::new();
2007            let mut expected_block_positions = Vec::new();
2008            let input_text = wraps_snapshot.text();
2009            for (row, input_line) in input_text.split('\n').enumerate() {
2010                let row = row as u32;
2011                if row > 0 {
2012                    expected_text.push('\n');
2013                }
2014
2015                let buffer_row = input_buffer_rows[wraps_snapshot
2016                    .to_point(WrapPoint::new(row, 0), Bias::Left)
2017                    .row as usize];
2018
2019                while let Some((block_row, block)) = sorted_blocks_iter.peek() {
2020                    if *block_row == row && block.disposition() == BlockDisposition::Above {
2021                        let (_, block) = sorted_blocks_iter.next().unwrap();
2022                        let height = block.height() as usize;
2023                        expected_block_positions
2024                            .push((expected_text.matches('\n').count() as u32, block));
2025                        let text = "\n".repeat(height);
2026                        expected_text.push_str(&text);
2027                        for _ in 0..height {
2028                            expected_buffer_rows.push(None);
2029                        }
2030                    } else {
2031                        break;
2032                    }
2033                }
2034
2035                let soft_wrapped = wraps_snapshot.to_tab_point(WrapPoint::new(row, 0)).column() > 0;
2036                expected_buffer_rows.push(if soft_wrapped { None } else { buffer_row });
2037                expected_text.push_str(input_line);
2038
2039                while let Some((block_row, block)) = sorted_blocks_iter.peek() {
2040                    if *block_row == row && block.disposition() == BlockDisposition::Below {
2041                        let (_, block) = sorted_blocks_iter.next().unwrap();
2042                        let height = block.height() as usize;
2043                        expected_block_positions
2044                            .push((expected_text.matches('\n').count() as u32 + 1, block));
2045                        let text = "\n".repeat(height);
2046                        expected_text.push_str(&text);
2047                        for _ in 0..height {
2048                            expected_buffer_rows.push(None);
2049                        }
2050                    } else {
2051                        break;
2052                    }
2053                }
2054            }
2055
2056            let expected_lines = expected_text.split('\n').collect::<Vec<_>>();
2057            let expected_row_count = expected_lines.len();
2058            for start_row in 0..expected_row_count {
2059                let expected_text = expected_lines[start_row..].join("\n");
2060                let actual_text = blocks_snapshot
2061                    .chunks(
2062                        start_row as u32..blocks_snapshot.max_point().row + 1,
2063                        false,
2064                        false,
2065                        Highlights::default(),
2066                    )
2067                    .map(|chunk| chunk.text)
2068                    .collect::<String>();
2069                assert_eq!(
2070                    actual_text, expected_text,
2071                    "incorrect text starting from row {}",
2072                    start_row
2073                );
2074                assert_eq!(
2075                    blocks_snapshot
2076                        .buffer_rows(BlockRow(start_row as u32))
2077                        .map(|row| row.map(|r| r.0))
2078                        .collect::<Vec<_>>(),
2079                    &expected_buffer_rows[start_row..]
2080                );
2081            }
2082
2083            assert_eq!(
2084                blocks_snapshot
2085                    .blocks_in_range(0..(expected_row_count as u32))
2086                    .map(|(row, block)| (row, block.clone().into()))
2087                    .collect::<Vec<_>>(),
2088                expected_block_positions
2089            );
2090
2091            for (_, expected_block) in
2092                blocks_snapshot.blocks_in_range(0..(expected_row_count as u32))
2093            {
2094                let actual_block = blocks_snapshot.block_for_id(expected_block.id());
2095                assert_eq!(
2096                    actual_block.map(|block| block.id()),
2097                    Some(expected_block.id())
2098                );
2099            }
2100
2101            for (block_row, block) in expected_block_positions {
2102                if let BlockType::Custom(block_id) = block.block_type() {
2103                    assert_eq!(
2104                        blocks_snapshot.row_for_block(block_id),
2105                        Some(BlockRow(block_row))
2106                    );
2107                }
2108            }
2109
2110            let mut expected_longest_rows = Vec::new();
2111            let mut longest_line_len = -1_isize;
2112            for (row, line) in expected_lines.iter().enumerate() {
2113                let row = row as u32;
2114
2115                assert_eq!(
2116                    blocks_snapshot.line_len(BlockRow(row)),
2117                    line.len() as u32,
2118                    "invalid line len for row {}",
2119                    row
2120                );
2121
2122                let line_char_count = line.chars().count() as isize;
2123                match line_char_count.cmp(&longest_line_len) {
2124                    Ordering::Less => {}
2125                    Ordering::Equal => expected_longest_rows.push(row),
2126                    Ordering::Greater => {
2127                        longest_line_len = line_char_count;
2128                        expected_longest_rows.clear();
2129                        expected_longest_rows.push(row);
2130                    }
2131                }
2132            }
2133
2134            let longest_row = blocks_snapshot.longest_row();
2135            assert!(
2136                expected_longest_rows.contains(&longest_row),
2137                "incorrect longest row {}. expected {:?} with length {}",
2138                longest_row,
2139                expected_longest_rows,
2140                longest_line_len,
2141            );
2142
2143            for row in 0..=blocks_snapshot.wrap_snapshot.max_point().row() {
2144                let wrap_point = WrapPoint::new(row, 0);
2145                let block_point = blocks_snapshot.to_block_point(wrap_point);
2146                assert_eq!(blocks_snapshot.to_wrap_point(block_point), wrap_point);
2147            }
2148
2149            let mut block_point = BlockPoint::new(0, 0);
2150            for c in expected_text.chars() {
2151                let left_point = blocks_snapshot.clip_point(block_point, Bias::Left);
2152                let left_buffer_point = blocks_snapshot.to_point(left_point, Bias::Left);
2153                assert_eq!(
2154                    blocks_snapshot.to_block_point(blocks_snapshot.to_wrap_point(left_point)),
2155                    left_point
2156                );
2157                assert_eq!(
2158                    left_buffer_point,
2159                    buffer_snapshot.clip_point(left_buffer_point, Bias::Right),
2160                    "{:?} is not valid in buffer coordinates",
2161                    left_point
2162                );
2163
2164                let right_point = blocks_snapshot.clip_point(block_point, Bias::Right);
2165                let right_buffer_point = blocks_snapshot.to_point(right_point, Bias::Right);
2166                assert_eq!(
2167                    blocks_snapshot.to_block_point(blocks_snapshot.to_wrap_point(right_point)),
2168                    right_point
2169                );
2170                assert_eq!(
2171                    right_buffer_point,
2172                    buffer_snapshot.clip_point(right_buffer_point, Bias::Left),
2173                    "{:?} is not valid in buffer coordinates",
2174                    right_point
2175                );
2176
2177                if c == '\n' {
2178                    block_point.0 += Point::new(1, 0);
2179                } else {
2180                    block_point.column += c.len_utf8() as u32;
2181                }
2182            }
2183        }
2184
2185        #[derive(Debug, Eq, PartialEq)]
2186        enum ExpectedBlock {
2187            ExcerptHeader {
2188                height: u8,
2189                starts_new_buffer: bool,
2190            },
2191            ExcerptFooter {
2192                height: u8,
2193                disposition: BlockDisposition,
2194            },
2195            Custom {
2196                disposition: BlockDisposition,
2197                id: CustomBlockId,
2198                height: u8,
2199            },
2200        }
2201
2202        impl BlockLike for ExpectedBlock {
2203            fn block_type(&self) -> BlockType {
2204                match self {
2205                    ExpectedBlock::Custom { id, .. } => BlockType::Custom(*id),
2206                    ExpectedBlock::ExcerptHeader { .. } => BlockType::Header,
2207                    ExpectedBlock::ExcerptFooter { .. } => BlockType::Footer,
2208                }
2209            }
2210
2211            fn disposition(&self) -> BlockDisposition {
2212                self.disposition()
2213            }
2214        }
2215
2216        impl ExpectedBlock {
2217            fn height(&self) -> u8 {
2218                match self {
2219                    ExpectedBlock::ExcerptHeader { height, .. } => *height,
2220                    ExpectedBlock::Custom { height, .. } => *height,
2221                    ExpectedBlock::ExcerptFooter { height, .. } => *height,
2222                }
2223            }
2224
2225            fn disposition(&self) -> BlockDisposition {
2226                match self {
2227                    ExpectedBlock::ExcerptHeader { .. } => BlockDisposition::Above,
2228                    ExpectedBlock::Custom { disposition, .. } => *disposition,
2229                    ExpectedBlock::ExcerptFooter { disposition, .. } => *disposition,
2230                }
2231            }
2232        }
2233
2234        impl From<Block> for ExpectedBlock {
2235            fn from(block: Block) -> Self {
2236                match block {
2237                    Block::Custom(block) => ExpectedBlock::Custom {
2238                        id: block.id,
2239                        disposition: block.disposition,
2240                        height: block.height,
2241                    },
2242                    Block::ExcerptHeader {
2243                        height,
2244                        starts_new_buffer,
2245                        ..
2246                    } => ExpectedBlock::ExcerptHeader {
2247                        height,
2248                        starts_new_buffer,
2249                    },
2250                    Block::ExcerptFooter {
2251                        height,
2252                        disposition,
2253                        ..
2254                    } => ExpectedBlock::ExcerptFooter {
2255                        height,
2256                        disposition,
2257                    },
2258                }
2259            }
2260        }
2261    }
2262
2263    fn init_test(cx: &mut gpui::AppContext) {
2264        let settings = SettingsStore::test(cx);
2265        cx.set_global(settings);
2266        theme::init(theme::LoadThemes::JustBase, cx);
2267        assets::Assets.load_test_fonts(cx);
2268    }
2269
2270    impl Block {
2271        fn as_custom(&self) -> Option<&CustomBlock> {
2272            match self {
2273                Block::Custom(block) => Some(block),
2274                Block::ExcerptHeader { .. } => None,
2275                Block::ExcerptFooter { .. } => None,
2276            }
2277        }
2278    }
2279
2280    impl BlockSnapshot {
2281        fn to_point(&self, point: BlockPoint, bias: Bias) -> Point {
2282            self.wrap_snapshot.to_point(self.to_wrap_point(point), bias)
2283        }
2284    }
2285}