block_map.rs

  1use super::wrap_map::{self, Edit as WrapEdit, Snapshot as WrapSnapshot, WrapPoint};
  2use buffer::{rope, Anchor, Bias, Edit, Point, Rope, ToOffset, ToPoint as _};
  3use gpui::{fonts::HighlightStyle, AppContext, ModelHandle};
  4use language::{Buffer, HighlightedChunk};
  5use parking_lot::Mutex;
  6use std::{
  7    cmp,
  8    collections::HashSet,
  9    iter,
 10    ops::Range,
 11    slice,
 12    sync::{
 13        atomic::{AtomicUsize, Ordering::SeqCst},
 14        Arc,
 15    },
 16};
 17use sum_tree::SumTree;
 18
 19pub struct BlockMap {
 20    buffer: ModelHandle<Buffer>,
 21    next_block_id: AtomicUsize,
 22    wrap_snapshot: Mutex<WrapSnapshot>,
 23    blocks: Vec<Arc<Block>>,
 24    transforms: Mutex<SumTree<Transform>>,
 25}
 26
 27pub struct BlockMapWriter<'a>(&'a mut BlockMap);
 28
 29pub struct BlockSnapshot {
 30    wrap_snapshot: WrapSnapshot,
 31    transforms: SumTree<Transform>,
 32}
 33
 34#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Hash)]
 35pub struct BlockId(usize);
 36
 37#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
 38pub struct BlockPoint(pub super::Point);
 39
 40#[derive(Debug)]
 41struct Block {
 42    id: BlockId,
 43    position: Anchor,
 44    text: Rope,
 45    runs: Vec<(usize, HighlightStyle)>,
 46    disposition: BlockDisposition,
 47}
 48
 49#[derive(Clone)]
 50pub struct BlockProperties<P, T>
 51where
 52    P: Clone,
 53    T: Clone,
 54{
 55    position: P,
 56    text: T,
 57    runs: Vec<(usize, HighlightStyle)>,
 58    disposition: BlockDisposition,
 59}
 60
 61#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
 62enum BlockDisposition {
 63    Above,
 64    Below,
 65}
 66
 67#[derive(Clone, Debug)]
 68struct Transform {
 69    summary: TransformSummary,
 70    block: Option<Arc<Block>>,
 71}
 72
 73#[derive(Copy, Clone, Debug, Default)]
 74struct TransformSummary {
 75    input_rows: u32,
 76    output_rows: u32,
 77}
 78
 79pub struct HighlightedChunks<'a> {
 80    transforms: sum_tree::Cursor<'a, Transform, (OutputRow, InputRow)>,
 81    input_chunks: wrap_map::HighlightedChunks<'a>,
 82    input_chunk: HighlightedChunk<'a>,
 83    block_chunks: Option<BlockChunks<'a>>,
 84    output_row: u32,
 85    max_output_row: u32,
 86}
 87
 88struct BlockChunks<'a> {
 89    chunks: rope::Chunks<'a>,
 90    runs: iter::Peekable<slice::Iter<'a, (usize, HighlightStyle)>>,
 91    chunk: Option<&'a str>,
 92    run_start: usize,
 93    offset: usize,
 94}
 95
 96#[derive(Copy, Clone, Default, Debug, PartialEq, Eq, PartialOrd, Ord)]
 97struct InputRow(u32);
 98
 99#[derive(Copy, Clone, Default, Debug, PartialEq, Eq, PartialOrd, Ord)]
100struct OutputRow(u32);
101
102impl BlockMap {
103    pub fn new(buffer: ModelHandle<Buffer>, wrap_snapshot: WrapSnapshot) -> Self {
104        Self {
105            buffer,
106            next_block_id: AtomicUsize::new(0),
107            blocks: Vec::new(),
108            transforms: Mutex::new(SumTree::from_item(
109                Transform::isomorphic(wrap_snapshot.max_point().row() + 1),
110                &(),
111            )),
112            wrap_snapshot: Mutex::new(wrap_snapshot),
113        }
114    }
115
116    pub fn read(
117        &self,
118        wrap_snapshot: WrapSnapshot,
119        edits: Vec<WrapEdit>,
120        cx: &AppContext,
121    ) -> BlockSnapshot {
122        self.apply_edits(&wrap_snapshot, edits, cx);
123        *self.wrap_snapshot.lock() = wrap_snapshot.clone();
124        BlockSnapshot {
125            wrap_snapshot,
126            transforms: self.transforms.lock().clone(),
127        }
128    }
129
130    pub fn write(
131        &mut self,
132        wrap_snapshot: WrapSnapshot,
133        edits: Vec<WrapEdit>,
134        cx: &AppContext,
135    ) -> BlockMapWriter {
136        self.apply_edits(&wrap_snapshot, edits, cx);
137        *self.wrap_snapshot.lock() = wrap_snapshot;
138        BlockMapWriter(self)
139    }
140
141    fn apply_edits(&self, wrap_snapshot: &WrapSnapshot, edits: Vec<WrapEdit>, cx: &AppContext) {
142        let buffer = self.buffer.read(cx);
143        let mut transforms = self.transforms.lock();
144        let mut new_transforms = SumTree::new();
145        let mut cursor = transforms.cursor::<InputRow>();
146        let mut edits = edits.into_iter().peekable();
147        let mut last_block_ix = 0;
148        let mut blocks_in_edit = Vec::new();
149
150        while let Some(mut edit) = edits.next() {
151            new_transforms.push_tree(
152                cursor.slice(&InputRow(edit.old.start), Bias::Left, &()),
153                &(),
154            );
155
156            let transform_start = cursor.start().0;
157            edit.new.start -= edit.old.start - transform_start;
158            edit.old.start = transform_start;
159
160            loop {
161                if edit.old.end > cursor.start().0 {
162                    cursor.seek(&InputRow(edit.old.end), Bias::Left, &());
163                    cursor.next(&());
164                    while let Some(item) = cursor.item() {
165                        if item.is_isomorphic() {
166                            break;
167                        } else {
168                            cursor.next(&());
169                        }
170                    }
171                    let transform_end = cursor.start().0;
172                    edit.new.end += transform_end - edit.old.end;
173                    edit.old.end = transform_end;
174                }
175
176                if let Some(next_edit) = edits.peek() {
177                    if edit.old.end >= next_edit.old.start {
178                        let delta = next_edit.new.len() as i32 - next_edit.old.len() as i32;
179                        edit.old.end = cmp::max(next_edit.old.end, edit.old.end);
180                        edit.new.end = (edit.new.end as i32 + delta) as u32;
181                        edits.next();
182                    } else {
183                        break;
184                    }
185                } else {
186                    break;
187                }
188            }
189
190            let start_anchor = buffer.anchor_before(Point::new(edit.new.start, 0));
191            let end_anchor = buffer.anchor_after(Point::new(edit.new.end, 0));
192            let start_block_ix = match self.blocks[last_block_ix..]
193                .binary_search_by(|probe| probe.position.cmp(&start_anchor, buffer).unwrap())
194            {
195                Ok(ix) | Err(ix) => last_block_ix + ix,
196            };
197            let end_block_ix = match self.blocks[start_block_ix..]
198                .binary_search_by(|probe| probe.position.cmp(&end_anchor, buffer).unwrap())
199            {
200                Ok(ix) | Err(ix) => start_block_ix + ix,
201            };
202            last_block_ix = end_block_ix;
203
204            blocks_in_edit.clear();
205            blocks_in_edit.extend(
206                self.blocks[start_block_ix..end_block_ix]
207                    .iter()
208                    .map(|block| (block.position.to_point(buffer).row, block)),
209            );
210            blocks_in_edit.sort_unstable_by_key(|(row, block)| (*row, block.disposition));
211
212            for (row, block) in blocks_in_edit.iter().copied() {
213                let insertion_row = if block.disposition.is_above() {
214                    row
215                } else {
216                    row + 1
217                };
218
219                let new_transforms_end = new_transforms.summary().input_rows;
220                if new_transforms_end < insertion_row {
221                    new_transforms.push(
222                        Transform::isomorphic(insertion_row - new_transforms_end),
223                        &(),
224                    );
225                }
226
227                new_transforms.push(Transform::block(block.clone()), &());
228            }
229
230            let new_transforms_end = new_transforms.summary().input_rows;
231            if new_transforms_end < edit.new.end {
232                new_transforms.push(
233                    Transform::isomorphic(edit.new.end - new_transforms_end),
234                    &(),
235                );
236            }
237        }
238        new_transforms.push_tree(cursor.suffix(&()), &());
239        drop(cursor);
240        *transforms = new_transforms;
241    }
242}
243
244impl BlockPoint {
245    fn new(row: u32, column: u32) -> Self {
246        Self(Point::new(row, column))
247    }
248}
249
250impl std::ops::Deref for BlockPoint {
251    type Target = Point;
252
253    fn deref(&self) -> &Self::Target {
254        &self.0
255    }
256}
257
258impl std::ops::DerefMut for BlockPoint {
259    fn deref_mut(&mut self) -> &mut Self::Target {
260        &mut self.0
261    }
262}
263
264impl<'a> BlockMapWriter<'a> {
265    pub fn insert<P, T>(
266        &mut self,
267        blocks: impl IntoIterator<Item = BlockProperties<P, T>>,
268        cx: &AppContext,
269    ) -> Vec<BlockId>
270    where
271        P: ToOffset + Clone,
272        T: Into<Rope> + Clone,
273    {
274        let buffer = self.0.buffer.read(cx);
275        let mut ids = Vec::new();
276        let mut edits = Vec::<Edit<u32>>::new();
277
278        for block in blocks {
279            let id = BlockId(self.0.next_block_id.fetch_add(1, SeqCst));
280            ids.push(id);
281
282            let position = buffer.anchor_before(block.position);
283            let row = position.to_point(buffer).row;
284
285            let block_ix = match self
286                .0
287                .blocks
288                .binary_search_by(|probe| probe.position.cmp(&position, buffer).unwrap())
289            {
290                Ok(ix) | Err(ix) => ix,
291            };
292            let mut text = block.text.into();
293            text.push("\n");
294            self.0.blocks.insert(
295                block_ix,
296                Arc::new(Block {
297                    id,
298                    position,
299                    text,
300                    runs: block.runs,
301                    disposition: block.disposition,
302                }),
303            );
304
305            if let Err(edit_ix) = edits.binary_search_by_key(&row, |edit| edit.old.start) {
306                edits.insert(
307                    edit_ix,
308                    Edit {
309                        old: row..(row + 1),
310                        new: row..(row + 1),
311                    },
312                );
313            }
314        }
315
316        self.0.apply_edits(&*self.0.wrap_snapshot.lock(), edits, cx);
317        ids
318    }
319
320    pub fn remove(&mut self, _: HashSet<BlockId>, _: &AppContext) {
321        todo!()
322    }
323}
324
325impl BlockSnapshot {
326    #[cfg(test)]
327    fn text(&mut self) -> String {
328        self.highlighted_chunks_for_rows(0..(self.max_point().0.row + 1))
329            .map(|chunk| chunk.text)
330            .collect()
331    }
332
333    pub fn highlighted_chunks_for_rows(&mut self, rows: Range<u32>) -> HighlightedChunks {
334        let mut cursor = self.transforms.cursor::<(OutputRow, InputRow)>();
335        cursor.seek(&OutputRow(rows.start), Bias::Right, &());
336        let (input_start, output_start) = cursor.start();
337        let row_overshoot = rows.start - output_start.0;
338        let input_start_row = input_start.0 + row_overshoot;
339        let input_end_row = self.to_wrap_point(BlockPoint::new(rows.end, 0)).row();
340        let input_chunks = self
341            .wrap_snapshot
342            .highlighted_chunks_for_rows(input_start_row..input_end_row);
343        HighlightedChunks {
344            input_chunks,
345            input_chunk: Default::default(),
346            block_chunks: None,
347            transforms: cursor,
348            output_row: rows.start,
349            max_output_row: rows.end,
350        }
351    }
352
353    pub fn max_point(&self) -> BlockPoint {
354        self.to_block_point(self.wrap_snapshot.max_point())
355    }
356
357    pub fn clip_point(&self, point: BlockPoint, bias: Bias) -> BlockPoint {
358        let mut cursor = self.transforms.cursor::<(OutputRow, InputRow)>();
359        cursor.seek(&OutputRow(point.row), Bias::Right, &());
360        if let Some(transform) = cursor.item() {
361            if transform.is_isomorphic() {
362                let (output_start_row, input_start_row) = cursor.start();
363                let output_overshoot = point.row - output_start_row.0;
364                let input_point = self.wrap_snapshot.clip_point(
365                    WrapPoint::new(input_start_row.0 + output_overshoot, point.column),
366                    bias,
367                );
368                let input_overshoot = input_point.row() - input_start_row.0;
369                BlockPoint::new(output_start_row.0 + input_overshoot, input_point.column())
370            } else {
371                if bias == Bias::Left && cursor.start().1 .0 > 0
372                    || cursor.end(&()).1 .0 == self.wrap_snapshot.max_point().row()
373                {
374                    loop {
375                        cursor.prev(&());
376                        let transform = cursor.item().unwrap();
377                        if transform.is_isomorphic() {
378                            return BlockPoint::new(cursor.end(&()).0 .0 - 1, 0);
379                        }
380                    }
381                } else {
382                    loop {
383                        cursor.next(&());
384                        let transform = cursor.item().unwrap();
385                        if transform.is_isomorphic() {
386                            return BlockPoint::new(cursor.start().0 .0, 0);
387                        }
388                    }
389                }
390            }
391        } else {
392            self.max_point()
393        }
394    }
395
396    pub fn to_block_point(&self, wrap_point: WrapPoint) -> BlockPoint {
397        let mut cursor = self.transforms.cursor::<(InputRow, OutputRow)>();
398        cursor.seek(&InputRow(wrap_point.row()), Bias::Right, &());
399        while let Some(item) = cursor.item() {
400            if item.is_isomorphic() {
401                break;
402            }
403            cursor.next(&());
404        }
405        let (input_start, output_start) = cursor.start();
406        let row_overshoot = wrap_point.row() - input_start.0;
407        BlockPoint::new(output_start.0 + row_overshoot, wrap_point.column())
408    }
409
410    pub fn to_wrap_point(&self, block_point: BlockPoint) -> WrapPoint {
411        let mut cursor = self.transforms.cursor::<(OutputRow, InputRow)>();
412        cursor.seek(&OutputRow(block_point.0.row), Bias::Right, &());
413        let (output_start, input_start) = cursor.start();
414        let row_overshoot = block_point.0.row - output_start.0;
415        WrapPoint::new(input_start.0 + row_overshoot, block_point.0.column)
416    }
417}
418
419impl Transform {
420    fn isomorphic(rows: u32) -> Self {
421        Self {
422            summary: TransformSummary {
423                input_rows: rows,
424                output_rows: rows,
425            },
426            block: None,
427        }
428    }
429
430    fn block(block: Arc<Block>) -> Self {
431        Self {
432            summary: TransformSummary {
433                input_rows: 0,
434                output_rows: block.text.summary().lines.row,
435            },
436            block: Some(block),
437        }
438    }
439
440    fn is_isomorphic(&self) -> bool {
441        self.block.is_none()
442    }
443}
444
445impl<'a> Iterator for HighlightedChunks<'a> {
446    type Item = HighlightedChunk<'a>;
447
448    fn next(&mut self) -> Option<Self::Item> {
449        if self.output_row >= self.max_output_row {
450            return None;
451        }
452
453        if let Some(block_chunks) = self.block_chunks.as_mut() {
454            if let Some(block_chunk) = block_chunks.next() {
455                self.output_row += block_chunk.text.matches('\n').count() as u32;
456                return Some(block_chunk);
457            } else {
458                self.block_chunks.take();
459            }
460        }
461
462        let transform = self.transforms.item()?;
463        if let Some(block) = transform.block.as_ref() {
464            let block_start = self.transforms.start().0 .0;
465            let block_end = self.transforms.end(&()).0 .0;
466            let start_row_in_block = self.output_row - block_start;
467            let end_row_in_block = cmp::min(self.max_output_row, block_end) - block_start;
468            self.transforms.next(&());
469            let mut block_chunks = BlockChunks::new(block, start_row_in_block..end_row_in_block);
470            if let Some(block_chunk) = block_chunks.next() {
471                self.output_row += block_chunk.text.matches('\n').count() as u32;
472                return Some(block_chunk);
473            }
474        }
475
476        if self.input_chunk.text.is_empty() {
477            self.input_chunk = self.input_chunks.next()?;
478        }
479
480        let transform_end = self.transforms.end(&()).0 .0;
481        let (prefix_rows, prefix_bytes) =
482            offset_for_row(self.input_chunk.text, transform_end - self.output_row);
483        self.output_row += prefix_rows;
484        let (prefix, suffix) = self.input_chunk.text.split_at(prefix_bytes);
485        self.input_chunk.text = suffix;
486        if self.output_row == transform_end {
487            self.transforms.next(&());
488        }
489
490        Some(HighlightedChunk {
491            text: prefix,
492            ..self.input_chunk
493        })
494    }
495}
496
497impl<'a> BlockChunks<'a> {
498    fn new(block: &'a Block, row_range: Range<u32>) -> Self {
499        let point_range = Point::new(row_range.start, 0)..Point::new(row_range.end, 0);
500        let offset_range = block.text.point_to_offset(point_range.start)
501            ..block.text.point_to_offset(point_range.end);
502
503        let mut runs = block.runs.iter().peekable();
504        let mut run_start = 0;
505        while let Some((run_len, _)) = runs.peek() {
506            let run_end = run_start + run_len;
507            if run_end <= offset_range.start {
508                run_start = run_end;
509                runs.next();
510            } else {
511                break;
512            }
513        }
514
515        Self {
516            chunk: None,
517            run_start,
518            chunks: block.text.chunks_in_range(offset_range.clone()),
519            runs,
520            offset: offset_range.start,
521        }
522    }
523}
524
525impl<'a> Iterator for BlockChunks<'a> {
526    type Item = HighlightedChunk<'a>;
527
528    fn next(&mut self) -> Option<Self::Item> {
529        if self.chunk.is_none() {
530            self.chunk = self.chunks.next();
531        }
532
533        let chunk = self.chunk?;
534        let mut chunk_len = chunk.len();
535        let mut highlight_style = None;
536        if let Some((run_len, style)) = self.runs.peek() {
537            highlight_style = Some(style.clone());
538            let run_end_in_chunk = self.run_start + run_len - self.offset;
539            if run_end_in_chunk <= chunk_len {
540                chunk_len = run_end_in_chunk;
541                self.run_start += run_len;
542                self.runs.next();
543            }
544        }
545
546        self.offset += chunk_len;
547        let (chunk, suffix) = chunk.split_at(chunk_len);
548        self.chunk = if suffix.is_empty() {
549            None
550        } else {
551            Some(suffix)
552        };
553
554        Some(HighlightedChunk {
555            text: chunk,
556            highlight_id: Default::default(),
557            diagnostic: None,
558        })
559    }
560}
561
562impl sum_tree::Item for Transform {
563    type Summary = TransformSummary;
564
565    fn summary(&self) -> Self::Summary {
566        self.summary
567    }
568}
569
570impl sum_tree::Summary for TransformSummary {
571    type Context = ();
572
573    fn add_summary(&mut self, summary: &Self, _: &()) {
574        self.input_rows += summary.input_rows;
575        self.output_rows += summary.output_rows;
576    }
577}
578
579impl<'a> sum_tree::Dimension<'a, TransformSummary> for InputRow {
580    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
581        self.0 += summary.input_rows;
582    }
583}
584
585impl<'a> sum_tree::Dimension<'a, TransformSummary> for OutputRow {
586    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
587        self.0 += summary.output_rows;
588    }
589}
590
591impl BlockDisposition {
592    fn is_above(&self) -> bool {
593        matches!(self, BlockDisposition::Above)
594    }
595}
596
597// Count the number of bytes prior to a target row.
598// If the string doesn't contain the target row, return the total number of rows it does contain.
599// Otherwise return the target row itself.
600fn offset_for_row(s: &str, target_row: u32) -> (u32, usize) {
601    let mut row = 0;
602    let mut offset = 0;
603    for (ix, line) in s.split('\n').enumerate() {
604        if ix > 0 {
605            row += 1;
606            offset += 1;
607        }
608        if row as u32 >= target_row {
609            break;
610        }
611        offset += line.len();
612    }
613    (row, offset)
614}
615
616#[cfg(test)]
617mod tests {
618    use super::*;
619    use crate::display_map::{fold_map::FoldMap, tab_map::TabMap, wrap_map::WrapMap};
620    use buffer::RandomCharIter;
621    use language::Buffer;
622    use rand::prelude::*;
623    use std::env;
624
625    #[gpui::test]
626    fn test_basic_blocks(cx: &mut gpui::MutableAppContext) {
627        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
628        let font_id = cx
629            .font_cache()
630            .select_font(family_id, &Default::default())
631            .unwrap();
632
633        let text = "aaa\nbbb\nccc\nddd\n";
634
635        let buffer = cx.add_model(|cx| Buffer::new(0, text, cx));
636        let (fold_map, folds_snapshot) = FoldMap::new(buffer.clone(), cx);
637        let (tab_map, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), 1);
638        let (wrap_map, wraps_snapshot) = WrapMap::new(tabs_snapshot, font_id, 14.0, None, cx);
639        let mut block_map = BlockMap::new(buffer.clone(), wraps_snapshot.clone());
640
641        let mut writer = block_map.write(wraps_snapshot.clone(), vec![], cx);
642        writer.insert(
643            vec![
644                BlockProperties {
645                    position: Point::new(1, 0),
646                    text: "BLOCK 1",
647                    disposition: BlockDisposition::Above,
648                    runs: vec![],
649                },
650                BlockProperties {
651                    position: Point::new(1, 2),
652                    text: "BLOCK 2",
653                    disposition: BlockDisposition::Above,
654                    runs: vec![],
655                },
656                BlockProperties {
657                    position: Point::new(3, 2),
658                    text: "BLOCK 3",
659                    disposition: BlockDisposition::Below,
660                    runs: vec![],
661                },
662            ],
663            cx,
664        );
665
666        let mut snapshot = block_map.read(wraps_snapshot, vec![], cx);
667        assert_eq!(
668            snapshot.text(),
669            "aaa\nBLOCK 1\nBLOCK 2\nbbb\nccc\nddd\nBLOCK 3\n"
670        );
671        assert_eq!(
672            snapshot.to_block_point(WrapPoint::new(1, 0)),
673            BlockPoint::new(3, 0)
674        );
675
676        // Insert a line break, separating two block decorations into separate
677        // lines.
678        buffer.update(cx, |buffer, cx| {
679            buffer.edit([Point::new(1, 1)..Point::new(1, 1)], "!!!\n", cx)
680        });
681
682        let (folds_snapshot, fold_edits) = fold_map.read(cx);
683        let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
684        let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
685            wrap_map.sync(tabs_snapshot, tab_edits, cx)
686        });
687        let mut snapshot = block_map.read(wraps_snapshot, wrap_edits, cx);
688        assert_eq!(
689            snapshot.text(),
690            "aaa\nBLOCK 1\nb!!!\nBLOCK 2\nbb\nccc\nddd\nBLOCK 3\n"
691        );
692    }
693
694    #[gpui::test(iterations = 100)]
695    fn test_random_blocks(cx: &mut gpui::MutableAppContext, mut rng: StdRng) {
696        let operations = env::var("OPERATIONS")
697            .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
698            .unwrap_or(10);
699
700        let wrap_width = Some(rng.gen_range(0.0..=1000.0));
701        let tab_size = 1;
702        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
703        let font_id = cx
704            .font_cache()
705            .select_font(family_id, &Default::default())
706            .unwrap();
707        let font_size = 14.0;
708
709        log::info!("Wrap width: {:?}", wrap_width);
710
711        let buffer = cx.add_model(|cx| {
712            let len = rng.gen_range(0..10);
713            let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
714            Buffer::new(0, text, cx)
715        });
716        let (fold_map, folds_snapshot) = FoldMap::new(buffer.clone(), cx);
717        let (tab_map, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), tab_size);
718        let (wrap_map, wraps_snapshot) =
719            WrapMap::new(tabs_snapshot, font_id, font_size, wrap_width, cx);
720        let mut block_map = BlockMap::new(buffer.clone(), wraps_snapshot);
721        let mut expected_blocks = Vec::new();
722
723        for _ in 0..operations {
724            match rng.gen_range(0..=100) {
725                0..=19 => {
726                    let wrap_width = if rng.gen_bool(0.2) {
727                        None
728                    } else {
729                        Some(rng.gen_range(0.0..=1000.0))
730                    };
731                    log::info!("Setting wrap width to {:?}", wrap_width);
732                    wrap_map.update(cx, |map, cx| map.set_wrap_width(wrap_width, cx));
733                }
734                20..=39 => {
735                    let block_count = rng.gen_range(1..=4);
736                    let block_properties = (0..block_count)
737                        .map(|_| {
738                            let buffer = buffer.read(cx);
739                            let position = buffer.anchor_before(rng.gen_range(0..=buffer.len()));
740
741                            let len = rng.gen_range(0..10);
742                            let text = Rope::from(
743                                RandomCharIter::new(&mut rng)
744                                    .take(len)
745                                    .collect::<String>()
746                                    .as_str(),
747                            );
748                            BlockProperties {
749                                position,
750                                text,
751                                runs: Vec::<(usize, HighlightStyle)>::new(),
752                                disposition: if rng.gen() {
753                                    BlockDisposition::Above
754                                } else {
755                                    BlockDisposition::Below
756                                },
757                            }
758                        })
759                        .collect::<Vec<_>>();
760
761                    let (folds_snapshot, fold_edits) = fold_map.read(cx);
762                    let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
763                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
764                        wrap_map.sync(tabs_snapshot, tab_edits, cx)
765                    });
766                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits, cx);
767                    let block_ids = block_map.insert(block_properties.clone(), cx);
768                    expected_blocks.extend(block_ids.into_iter().zip(block_properties));
769                }
770                40..=59 => {
771                    let block_count = rng.gen_range(1..=4.min(expected_blocks.len()));
772                    let block_ids_to_remove = (0..block_count)
773                        .map(|_| {
774                            expected_blocks
775                                .remove(rng.gen_range(0..expected_blocks.len()))
776                                .0
777                        })
778                        .collect();
779
780                    let (folds_snapshot, fold_edits) = fold_map.read(cx);
781                    let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
782                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
783                        wrap_map.sync(tabs_snapshot, tab_edits, cx)
784                    });
785                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits, cx);
786                    block_map.remove(block_ids_to_remove, cx);
787                }
788                _ => {
789                    buffer.update(cx, |buffer, _| buffer.randomly_edit(&mut rng, 5));
790                }
791            }
792
793            let (folds_snapshot, fold_edits) = fold_map.read(cx);
794            let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
795            let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
796                wrap_map.sync(tabs_snapshot, tab_edits, cx)
797            });
798            let mut blocks_snapshot = block_map.read(wraps_snapshot.clone(), wrap_edits, cx);
799            assert_eq!(
800                blocks_snapshot.transforms.summary().input_rows,
801                wraps_snapshot.max_point().row() + 1
802            );
803
804            let buffer = buffer.read(cx);
805            let mut sorted_blocks = expected_blocks
806                .iter()
807                .cloned()
808                .map(|(_, block)| BlockProperties {
809                    position: block.position.to_point(buffer),
810                    text: block.text,
811                    runs: block.runs,
812                    disposition: block.disposition,
813                })
814                .collect::<Vec<_>>();
815            sorted_blocks.sort_unstable_by_key(|block| (block.position.row, block.disposition));
816            let mut sorted_blocks = sorted_blocks.into_iter().peekable();
817
818            let mut expected_text = String::new();
819            let input_text = wraps_snapshot.text();
820            for (row, input_line) in input_text.split('\n').enumerate() {
821                let row = row as u32;
822                if row > 0 {
823                    expected_text.push('\n');
824                }
825
826                while let Some(block) = sorted_blocks.peek() {
827                    if block.position.row == row && block.disposition == BlockDisposition::Above {
828                        expected_text.extend(block.text.chunks());
829                        expected_text.push('\n');
830                        sorted_blocks.next();
831                    } else {
832                        break;
833                    }
834                }
835
836                expected_text.push_str(input_line);
837
838                while let Some(block) = sorted_blocks.peek() {
839                    if block.position.row == row && block.disposition == BlockDisposition::Below {
840                        expected_text.push('\n');
841                        expected_text.extend(block.text.chunks());
842                        sorted_blocks.next();
843                    } else {
844                        break;
845                    }
846                }
847            }
848
849            assert_eq!(blocks_snapshot.text(), expected_text);
850        }
851    }
852}