1mod anchor;
2pub mod locator;
3#[cfg(any(test, feature = "test-support"))]
4pub mod network;
5mod offset_utf16;
6pub mod operation_queue;
7mod patch;
8mod point;
9mod point_utf16;
10#[cfg(any(test, feature = "test-support"))]
11pub mod random_char_iter;
12pub mod rope;
13mod selection;
14pub mod subscription;
15#[cfg(test)]
16mod tests;
17
18pub use anchor::*;
19use anyhow::Result;
20use clock::ReplicaId;
21use collections::{HashMap, HashSet};
22use lazy_static::lazy_static;
23use locator::Locator;
24pub use offset_utf16::*;
25use operation_queue::OperationQueue;
26pub use patch::Patch;
27pub use point::*;
28pub use point_utf16::*;
29use postage::{barrier, oneshot, prelude::*};
30#[cfg(any(test, feature = "test-support"))]
31pub use random_char_iter::*;
32use regex::Regex;
33use rope::TextDimension;
34pub use rope::{Chunks, Rope, TextSummary};
35pub use selection::*;
36use std::{
37 borrow::Cow,
38 cmp::{self, Ordering, Reverse},
39 future::Future,
40 iter::Iterator,
41 ops::{self, Deref, Range, Sub},
42 str,
43 sync::Arc,
44 time::{Duration, Instant},
45};
46pub use subscription::*;
47pub use sum_tree::Bias;
48use sum_tree::{FilterCursor, SumTree};
49
50lazy_static! {
51 static ref CARRIAGE_RETURNS_REGEX: Regex = Regex::new("\r\n|\r").unwrap();
52}
53
54pub type TransactionId = clock::Local;
55
56pub struct Buffer {
57 snapshot: BufferSnapshot,
58 history: History,
59 deferred_ops: OperationQueue<Operation>,
60 deferred_replicas: HashSet<ReplicaId>,
61 replica_id: ReplicaId,
62 local_clock: clock::Local,
63 pub lamport_clock: clock::Lamport,
64 subscriptions: Topic,
65 edit_id_resolvers: HashMap<clock::Local, Vec<oneshot::Sender<()>>>,
66 version_barriers: Vec<(clock::Global, barrier::Sender)>,
67}
68
69#[derive(Clone, Debug)]
70pub struct BufferSnapshot {
71 replica_id: ReplicaId,
72 remote_id: u64,
73 visible_text: Rope,
74 deleted_text: Rope,
75 line_ending: LineEnding,
76 undo_map: UndoMap,
77 fragments: SumTree<Fragment>,
78 insertions: SumTree<InsertionFragment>,
79 pub version: clock::Global,
80}
81
82#[derive(Clone, Debug)]
83pub struct HistoryEntry {
84 transaction: Transaction,
85 first_edit_at: Instant,
86 last_edit_at: Instant,
87 suppress_grouping: bool,
88}
89
90#[derive(Clone, Debug)]
91pub struct Transaction {
92 pub id: TransactionId,
93 pub edit_ids: Vec<clock::Local>,
94 pub start: clock::Global,
95}
96
97#[derive(Clone, Copy, Debug, PartialEq)]
98pub enum LineEnding {
99 Unix,
100 Windows,
101}
102
103impl HistoryEntry {
104 pub fn transaction_id(&self) -> TransactionId {
105 self.transaction.id
106 }
107}
108
109struct History {
110 // TODO: Turn this into a String or Rope, maybe.
111 base_text: Arc<str>,
112 operations: HashMap<clock::Local, Operation>,
113 insertion_slices: HashMap<clock::Local, Vec<InsertionSlice>>,
114 undo_stack: Vec<HistoryEntry>,
115 redo_stack: Vec<HistoryEntry>,
116 transaction_depth: usize,
117 group_interval: Duration,
118}
119
120#[derive(Clone, Debug)]
121struct InsertionSlice {
122 insertion_id: clock::Local,
123 range: Range<usize>,
124}
125
126impl History {
127 pub fn new(base_text: Arc<str>) -> Self {
128 Self {
129 base_text,
130 operations: Default::default(),
131 insertion_slices: Default::default(),
132 undo_stack: Vec::new(),
133 redo_stack: Vec::new(),
134 transaction_depth: 0,
135 group_interval: Duration::from_millis(300),
136 }
137 }
138
139 fn push(&mut self, op: Operation) {
140 self.operations.insert(op.local_timestamp(), op);
141 }
142
143 fn start_transaction(
144 &mut self,
145 start: clock::Global,
146 now: Instant,
147 local_clock: &mut clock::Local,
148 ) -> Option<TransactionId> {
149 self.transaction_depth += 1;
150 if self.transaction_depth == 1 {
151 let id = local_clock.tick();
152 self.undo_stack.push(HistoryEntry {
153 transaction: Transaction {
154 id,
155 start,
156 edit_ids: Default::default(),
157 },
158 first_edit_at: now,
159 last_edit_at: now,
160 suppress_grouping: false,
161 });
162 Some(id)
163 } else {
164 None
165 }
166 }
167
168 fn end_transaction(&mut self, now: Instant) -> Option<&HistoryEntry> {
169 assert_ne!(self.transaction_depth, 0);
170 self.transaction_depth -= 1;
171 if self.transaction_depth == 0 {
172 if self
173 .undo_stack
174 .last()
175 .unwrap()
176 .transaction
177 .edit_ids
178 .is_empty()
179 {
180 self.undo_stack.pop();
181 None
182 } else {
183 self.redo_stack.clear();
184 let entry = self.undo_stack.last_mut().unwrap();
185 entry.last_edit_at = now;
186 Some(entry)
187 }
188 } else {
189 None
190 }
191 }
192
193 fn group(&mut self) -> Option<TransactionId> {
194 let mut count = 0;
195 let mut entries = self.undo_stack.iter();
196 if let Some(mut entry) = entries.next_back() {
197 while let Some(prev_entry) = entries.next_back() {
198 if !prev_entry.suppress_grouping
199 && entry.first_edit_at - prev_entry.last_edit_at <= self.group_interval
200 {
201 entry = prev_entry;
202 count += 1;
203 } else {
204 break;
205 }
206 }
207 }
208 self.group_trailing(count)
209 }
210
211 fn group_until(&mut self, transaction_id: TransactionId) {
212 let mut count = 0;
213 for entry in self.undo_stack.iter().rev() {
214 if entry.transaction_id() == transaction_id {
215 self.group_trailing(count);
216 break;
217 } else if entry.suppress_grouping {
218 break;
219 } else {
220 count += 1;
221 }
222 }
223 }
224
225 fn group_trailing(&mut self, n: usize) -> Option<TransactionId> {
226 let new_len = self.undo_stack.len() - n;
227 let (entries_to_keep, entries_to_merge) = self.undo_stack.split_at_mut(new_len);
228 if let Some(last_entry) = entries_to_keep.last_mut() {
229 for entry in &*entries_to_merge {
230 for edit_id in &entry.transaction.edit_ids {
231 last_entry.transaction.edit_ids.push(*edit_id);
232 }
233 }
234
235 if let Some(entry) = entries_to_merge.last_mut() {
236 last_entry.last_edit_at = entry.last_edit_at;
237 }
238 }
239
240 self.undo_stack.truncate(new_len);
241 self.undo_stack.last().map(|e| e.transaction.id)
242 }
243
244 fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
245 self.undo_stack.last_mut().map(|entry| {
246 entry.suppress_grouping = true;
247 &entry.transaction
248 })
249 }
250
251 fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
252 assert_eq!(self.transaction_depth, 0);
253 self.undo_stack.push(HistoryEntry {
254 transaction,
255 first_edit_at: now,
256 last_edit_at: now,
257 suppress_grouping: false,
258 });
259 self.redo_stack.clear();
260 }
261
262 fn push_undo(&mut self, op_id: clock::Local) {
263 assert_ne!(self.transaction_depth, 0);
264 if let Some(Operation::Edit(_)) = self.operations.get(&op_id) {
265 let last_transaction = self.undo_stack.last_mut().unwrap();
266 last_transaction.transaction.edit_ids.push(op_id);
267 }
268 }
269
270 fn pop_undo(&mut self) -> Option<&HistoryEntry> {
271 assert_eq!(self.transaction_depth, 0);
272 if let Some(entry) = self.undo_stack.pop() {
273 self.redo_stack.push(entry);
274 self.redo_stack.last()
275 } else {
276 None
277 }
278 }
279
280 fn remove_from_undo(&mut self, transaction_id: TransactionId) -> &[HistoryEntry] {
281 assert_eq!(self.transaction_depth, 0);
282
283 let redo_stack_start_len = self.redo_stack.len();
284 if let Some(entry_ix) = self
285 .undo_stack
286 .iter()
287 .rposition(|entry| entry.transaction.id == transaction_id)
288 {
289 self.redo_stack
290 .extend(self.undo_stack.drain(entry_ix..).rev());
291 }
292 &self.redo_stack[redo_stack_start_len..]
293 }
294
295 fn forget(&mut self, transaction_id: TransactionId) {
296 assert_eq!(self.transaction_depth, 0);
297 if let Some(entry_ix) = self
298 .undo_stack
299 .iter()
300 .rposition(|entry| entry.transaction.id == transaction_id)
301 {
302 self.undo_stack.remove(entry_ix);
303 } else if let Some(entry_ix) = self
304 .redo_stack
305 .iter()
306 .rposition(|entry| entry.transaction.id == transaction_id)
307 {
308 self.undo_stack.remove(entry_ix);
309 }
310 }
311
312 fn pop_redo(&mut self) -> Option<&HistoryEntry> {
313 assert_eq!(self.transaction_depth, 0);
314 if let Some(entry) = self.redo_stack.pop() {
315 self.undo_stack.push(entry);
316 self.undo_stack.last()
317 } else {
318 None
319 }
320 }
321
322 fn remove_from_redo(&mut self, transaction_id: TransactionId) -> &[HistoryEntry] {
323 assert_eq!(self.transaction_depth, 0);
324
325 let undo_stack_start_len = self.undo_stack.len();
326 if let Some(entry_ix) = self
327 .redo_stack
328 .iter()
329 .rposition(|entry| entry.transaction.id == transaction_id)
330 {
331 self.undo_stack
332 .extend(self.redo_stack.drain(entry_ix..).rev());
333 }
334 &self.undo_stack[undo_stack_start_len..]
335 }
336}
337
338#[derive(Clone, Default, Debug)]
339struct UndoMap(HashMap<clock::Local, Vec<(clock::Local, u32)>>);
340
341impl UndoMap {
342 fn insert(&mut self, undo: &UndoOperation) {
343 for (edit_id, count) in &undo.counts {
344 self.0.entry(*edit_id).or_default().push((undo.id, *count));
345 }
346 }
347
348 fn is_undone(&self, edit_id: clock::Local) -> bool {
349 self.undo_count(edit_id) % 2 == 1
350 }
351
352 fn was_undone(&self, edit_id: clock::Local, version: &clock::Global) -> bool {
353 let undo_count = self
354 .0
355 .get(&edit_id)
356 .unwrap_or(&Vec::new())
357 .iter()
358 .filter(|(undo_id, _)| version.observed(*undo_id))
359 .map(|(_, undo_count)| *undo_count)
360 .max()
361 .unwrap_or(0);
362 undo_count % 2 == 1
363 }
364
365 fn undo_count(&self, edit_id: clock::Local) -> u32 {
366 self.0
367 .get(&edit_id)
368 .unwrap_or(&Vec::new())
369 .iter()
370 .map(|(_, undo_count)| *undo_count)
371 .max()
372 .unwrap_or(0)
373 }
374}
375
376struct Edits<'a, D: TextDimension, F: FnMut(&FragmentSummary) -> bool> {
377 visible_cursor: rope::Cursor<'a>,
378 deleted_cursor: rope::Cursor<'a>,
379 fragments_cursor: Option<FilterCursor<'a, F, Fragment, FragmentTextSummary>>,
380 undos: &'a UndoMap,
381 since: &'a clock::Global,
382 old_end: D,
383 new_end: D,
384 range: Range<(&'a Locator, usize)>,
385}
386
387#[derive(Clone, Debug, Default, Eq, PartialEq)]
388pub struct Edit<D> {
389 pub old: Range<D>,
390 pub new: Range<D>,
391}
392
393impl<D> Edit<D>
394where
395 D: Sub<D, Output = D> + PartialEq + Copy,
396{
397 pub fn old_len(&self) -> D {
398 self.old.end - self.old.start
399 }
400
401 pub fn new_len(&self) -> D {
402 self.new.end - self.new.start
403 }
404
405 pub fn is_empty(&self) -> bool {
406 self.old.start == self.old.end && self.new.start == self.new.end
407 }
408}
409
410impl<D1, D2> Edit<(D1, D2)> {
411 pub fn flatten(self) -> (Edit<D1>, Edit<D2>) {
412 (
413 Edit {
414 old: self.old.start.0..self.old.end.0,
415 new: self.new.start.0..self.new.end.0,
416 },
417 Edit {
418 old: self.old.start.1..self.old.end.1,
419 new: self.new.start.1..self.new.end.1,
420 },
421 )
422 }
423}
424
425#[derive(Copy, Clone, Debug, Default, Eq, PartialEq, PartialOrd, Ord)]
426pub struct InsertionTimestamp {
427 pub replica_id: ReplicaId,
428 pub local: clock::Seq,
429 pub lamport: clock::Seq,
430}
431
432impl InsertionTimestamp {
433 pub fn local(&self) -> clock::Local {
434 clock::Local {
435 replica_id: self.replica_id,
436 value: self.local,
437 }
438 }
439
440 pub fn lamport(&self) -> clock::Lamport {
441 clock::Lamport {
442 replica_id: self.replica_id,
443 value: self.lamport,
444 }
445 }
446}
447
448#[derive(Eq, PartialEq, Clone, Debug)]
449pub struct Fragment {
450 pub id: Locator,
451 pub insertion_timestamp: InsertionTimestamp,
452 pub insertion_offset: usize,
453 pub len: usize,
454 pub visible: bool,
455 pub deletions: HashSet<clock::Local>,
456 pub max_undos: clock::Global,
457}
458
459#[derive(Eq, PartialEq, Clone, Debug)]
460pub struct FragmentSummary {
461 text: FragmentTextSummary,
462 max_id: Locator,
463 max_version: clock::Global,
464 min_insertion_version: clock::Global,
465 max_insertion_version: clock::Global,
466}
467
468#[derive(Copy, Default, Clone, Debug, PartialEq, Eq)]
469struct FragmentTextSummary {
470 visible: usize,
471 deleted: usize,
472}
473
474impl<'a> sum_tree::Dimension<'a, FragmentSummary> for FragmentTextSummary {
475 fn add_summary(&mut self, summary: &'a FragmentSummary, _: &Option<clock::Global>) {
476 self.visible += summary.text.visible;
477 self.deleted += summary.text.deleted;
478 }
479}
480
481#[derive(Eq, PartialEq, Clone, Debug)]
482struct InsertionFragment {
483 timestamp: clock::Local,
484 split_offset: usize,
485 fragment_id: Locator,
486}
487
488#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord)]
489struct InsertionFragmentKey {
490 timestamp: clock::Local,
491 split_offset: usize,
492}
493
494#[derive(Clone, Debug, Eq, PartialEq)]
495pub enum Operation {
496 Edit(EditOperation),
497 Undo {
498 undo: UndoOperation,
499 lamport_timestamp: clock::Lamport,
500 },
501}
502
503#[derive(Clone, Debug, Eq, PartialEq)]
504pub struct EditOperation {
505 pub timestamp: InsertionTimestamp,
506 pub version: clock::Global,
507 pub ranges: Vec<Range<FullOffset>>,
508 pub new_text: Vec<Arc<str>>,
509}
510
511#[derive(Clone, Debug, Eq, PartialEq)]
512pub struct UndoOperation {
513 pub id: clock::Local,
514 pub counts: HashMap<clock::Local, u32>,
515 pub transaction_version: clock::Global,
516 pub version: clock::Global,
517}
518
519impl Buffer {
520 pub fn new(replica_id: u16, remote_id: u64, mut base_text: String) -> Buffer {
521 let line_ending = LineEnding::detect(&base_text);
522 LineEnding::normalize(&mut base_text);
523
524 let history = History::new(base_text.into());
525 let mut fragments = SumTree::new();
526 let mut insertions = SumTree::new();
527
528 let mut local_clock = clock::Local::new(replica_id);
529 let mut lamport_clock = clock::Lamport::new(replica_id);
530 let mut version = clock::Global::new();
531
532 let visible_text = Rope::from(history.base_text.as_ref());
533 if !visible_text.is_empty() {
534 let insertion_timestamp = InsertionTimestamp {
535 replica_id: 0,
536 local: 1,
537 lamport: 1,
538 };
539 local_clock.observe(insertion_timestamp.local());
540 lamport_clock.observe(insertion_timestamp.lamport());
541 version.observe(insertion_timestamp.local());
542 let fragment_id = Locator::between(&Locator::min(), &Locator::max());
543 let fragment = Fragment {
544 id: fragment_id,
545 insertion_timestamp,
546 insertion_offset: 0,
547 len: visible_text.len(),
548 visible: true,
549 deletions: Default::default(),
550 max_undos: Default::default(),
551 };
552 insertions.push(InsertionFragment::new(&fragment), &());
553 fragments.push(fragment, &None);
554 }
555
556 Buffer {
557 snapshot: BufferSnapshot {
558 replica_id,
559 remote_id,
560 visible_text,
561 deleted_text: Rope::new(),
562 line_ending,
563 fragments,
564 insertions,
565 version,
566 undo_map: Default::default(),
567 },
568 history,
569 deferred_ops: OperationQueue::new(),
570 deferred_replicas: HashSet::default(),
571 replica_id,
572 local_clock,
573 lamport_clock,
574 subscriptions: Default::default(),
575 edit_id_resolvers: Default::default(),
576 version_barriers: Default::default(),
577 }
578 }
579
580 pub fn version(&self) -> clock::Global {
581 self.version.clone()
582 }
583
584 pub fn snapshot(&self) -> BufferSnapshot {
585 self.snapshot.clone()
586 }
587
588 pub fn replica_id(&self) -> ReplicaId {
589 self.local_clock.replica_id
590 }
591
592 pub fn remote_id(&self) -> u64 {
593 self.remote_id
594 }
595
596 pub fn deferred_ops_len(&self) -> usize {
597 self.deferred_ops.len()
598 }
599
600 pub fn transaction_group_interval(&self) -> Duration {
601 self.history.group_interval
602 }
603
604 pub fn edit<R, I, S, T>(&mut self, edits: R) -> Operation
605 where
606 R: IntoIterator<IntoIter = I>,
607 I: ExactSizeIterator<Item = (Range<S>, T)>,
608 S: ToOffset,
609 T: Into<Arc<str>>,
610 {
611 let edits = edits
612 .into_iter()
613 .map(|(range, new_text)| (range, new_text.into()));
614
615 self.start_transaction();
616 let timestamp = InsertionTimestamp {
617 replica_id: self.replica_id,
618 local: self.local_clock.tick().value,
619 lamport: self.lamport_clock.tick().value,
620 };
621 let operation = Operation::Edit(self.apply_local_edit(edits, timestamp));
622
623 self.history.push(operation.clone());
624 self.history.push_undo(operation.local_timestamp());
625 self.snapshot.version.observe(operation.local_timestamp());
626 self.end_transaction();
627 operation
628 }
629
630 fn apply_local_edit<S: ToOffset, T: Into<Arc<str>>>(
631 &mut self,
632 edits: impl ExactSizeIterator<Item = (Range<S>, T)>,
633 timestamp: InsertionTimestamp,
634 ) -> EditOperation {
635 let mut edits_patch = Patch::default();
636 let mut edit_op = EditOperation {
637 timestamp,
638 version: self.version(),
639 ranges: Vec::with_capacity(edits.len()),
640 new_text: Vec::with_capacity(edits.len()),
641 };
642 let mut new_insertions = Vec::new();
643 let mut insertion_offset = 0;
644 let mut insertion_slices = Vec::new();
645
646 let mut edits = edits
647 .map(|(range, new_text)| (range.to_offset(&*self), new_text))
648 .peekable();
649
650 let mut new_ropes =
651 RopeBuilder::new(self.visible_text.cursor(0), self.deleted_text.cursor(0));
652 let mut old_fragments = self.fragments.cursor::<FragmentTextSummary>();
653 let mut new_fragments =
654 old_fragments.slice(&edits.peek().unwrap().0.start, Bias::Right, &None);
655 new_ropes.push_tree(new_fragments.summary().text);
656
657 let mut fragment_start = old_fragments.start().visible;
658 for (range, new_text) in edits {
659 let new_text = LineEnding::normalize_arc(new_text.into());
660 let fragment_end = old_fragments.end(&None).visible;
661
662 // If the current fragment ends before this range, then jump ahead to the first fragment
663 // that extends past the start of this range, reusing any intervening fragments.
664 if fragment_end < range.start {
665 // If the current fragment has been partially consumed, then consume the rest of it
666 // and advance to the next fragment before slicing.
667 if fragment_start > old_fragments.start().visible {
668 if fragment_end > fragment_start {
669 let mut suffix = old_fragments.item().unwrap().clone();
670 suffix.len = fragment_end - fragment_start;
671 suffix.insertion_offset += fragment_start - old_fragments.start().visible;
672 new_insertions.push(InsertionFragment::insert_new(&suffix));
673 new_ropes.push_fragment(&suffix, suffix.visible);
674 new_fragments.push(suffix, &None);
675 }
676 old_fragments.next(&None);
677 }
678
679 let slice = old_fragments.slice(&range.start, Bias::Right, &None);
680 new_ropes.push_tree(slice.summary().text);
681 new_fragments.push_tree(slice, &None);
682 fragment_start = old_fragments.start().visible;
683 }
684
685 let full_range_start = FullOffset(range.start + old_fragments.start().deleted);
686
687 // Preserve any portion of the current fragment that precedes this range.
688 if fragment_start < range.start {
689 let mut prefix = old_fragments.item().unwrap().clone();
690 prefix.len = range.start - fragment_start;
691 prefix.insertion_offset += fragment_start - old_fragments.start().visible;
692 prefix.id = Locator::between(&new_fragments.summary().max_id, &prefix.id);
693 new_insertions.push(InsertionFragment::insert_new(&prefix));
694 new_ropes.push_fragment(&prefix, prefix.visible);
695 new_fragments.push(prefix, &None);
696 fragment_start = range.start;
697 }
698
699 // Insert the new text before any existing fragments within the range.
700 if !new_text.is_empty() {
701 let new_start = new_fragments.summary().text.visible;
702
703 let fragment = Fragment {
704 id: Locator::between(
705 &new_fragments.summary().max_id,
706 old_fragments
707 .item()
708 .map_or(&Locator::max(), |old_fragment| &old_fragment.id),
709 ),
710 insertion_timestamp: timestamp,
711 insertion_offset,
712 len: new_text.len(),
713 deletions: Default::default(),
714 max_undos: Default::default(),
715 visible: true,
716 };
717 edits_patch.push(Edit {
718 old: fragment_start..fragment_start,
719 new: new_start..new_start + new_text.len(),
720 });
721 insertion_slices.push(fragment.insertion_slice());
722 new_insertions.push(InsertionFragment::insert_new(&fragment));
723 new_ropes.push_str(new_text.as_ref());
724 new_fragments.push(fragment, &None);
725 insertion_offset += new_text.len();
726 }
727
728 // Advance through every fragment that intersects this range, marking the intersecting
729 // portions as deleted.
730 while fragment_start < range.end {
731 let fragment = old_fragments.item().unwrap();
732 let fragment_end = old_fragments.end(&None).visible;
733 let mut intersection = fragment.clone();
734 let intersection_end = cmp::min(range.end, fragment_end);
735 if fragment.visible {
736 intersection.len = intersection_end - fragment_start;
737 intersection.insertion_offset += fragment_start - old_fragments.start().visible;
738 intersection.id =
739 Locator::between(&new_fragments.summary().max_id, &intersection.id);
740 intersection.deletions.insert(timestamp.local());
741 intersection.visible = false;
742 }
743 if intersection.len > 0 {
744 if fragment.visible && !intersection.visible {
745 let new_start = new_fragments.summary().text.visible;
746 edits_patch.push(Edit {
747 old: fragment_start..intersection_end,
748 new: new_start..new_start,
749 });
750 insertion_slices.push(intersection.insertion_slice());
751 }
752 new_insertions.push(InsertionFragment::insert_new(&intersection));
753 new_ropes.push_fragment(&intersection, fragment.visible);
754 new_fragments.push(intersection, &None);
755 fragment_start = intersection_end;
756 }
757 if fragment_end <= range.end {
758 old_fragments.next(&None);
759 }
760 }
761
762 let full_range_end = FullOffset(range.end + old_fragments.start().deleted);
763 edit_op.ranges.push(full_range_start..full_range_end);
764 edit_op.new_text.push(new_text);
765 }
766
767 // If the current fragment has been partially consumed, then consume the rest of it
768 // and advance to the next fragment before slicing.
769 if fragment_start > old_fragments.start().visible {
770 let fragment_end = old_fragments.end(&None).visible;
771 if fragment_end > fragment_start {
772 let mut suffix = old_fragments.item().unwrap().clone();
773 suffix.len = fragment_end - fragment_start;
774 suffix.insertion_offset += fragment_start - old_fragments.start().visible;
775 new_insertions.push(InsertionFragment::insert_new(&suffix));
776 new_ropes.push_fragment(&suffix, suffix.visible);
777 new_fragments.push(suffix, &None);
778 }
779 old_fragments.next(&None);
780 }
781
782 let suffix = old_fragments.suffix(&None);
783 new_ropes.push_tree(suffix.summary().text);
784 new_fragments.push_tree(suffix, &None);
785 let (visible_text, deleted_text) = new_ropes.finish();
786 drop(old_fragments);
787
788 self.snapshot.fragments = new_fragments;
789 self.snapshot.insertions.edit(new_insertions, &());
790 self.snapshot.visible_text = visible_text;
791 self.snapshot.deleted_text = deleted_text;
792 self.subscriptions.publish_mut(&edits_patch);
793 self.history
794 .insertion_slices
795 .insert(timestamp.local(), insertion_slices);
796 edit_op
797 }
798
799 pub fn set_line_ending(&mut self, line_ending: LineEnding) {
800 self.snapshot.line_ending = line_ending;
801 }
802
803 pub fn apply_ops<I: IntoIterator<Item = Operation>>(&mut self, ops: I) -> Result<()> {
804 let mut deferred_ops = Vec::new();
805 for op in ops {
806 self.history.push(op.clone());
807 if self.can_apply_op(&op) {
808 self.apply_op(op)?;
809 } else {
810 self.deferred_replicas.insert(op.replica_id());
811 deferred_ops.push(op);
812 }
813 }
814 self.deferred_ops.insert(deferred_ops);
815 self.flush_deferred_ops()?;
816 Ok(())
817 }
818
819 fn apply_op(&mut self, op: Operation) -> Result<()> {
820 match op {
821 Operation::Edit(edit) => {
822 if !self.version.observed(edit.timestamp.local()) {
823 self.apply_remote_edit(
824 &edit.version,
825 &edit.ranges,
826 &edit.new_text,
827 edit.timestamp,
828 );
829 self.snapshot.version.observe(edit.timestamp.local());
830 self.local_clock.observe(edit.timestamp.local());
831 self.lamport_clock.observe(edit.timestamp.lamport());
832 self.resolve_edit(edit.timestamp.local());
833 }
834 }
835 Operation::Undo {
836 undo,
837 lamport_timestamp,
838 } => {
839 if !self.version.observed(undo.id) {
840 self.apply_undo(&undo)?;
841 self.snapshot.version.observe(undo.id);
842 self.local_clock.observe(undo.id);
843 self.lamport_clock.observe(lamport_timestamp);
844 }
845 }
846 }
847 self.version_barriers
848 .retain(|(version, _)| !self.snapshot.version().observed_all(version));
849 Ok(())
850 }
851
852 fn apply_remote_edit(
853 &mut self,
854 version: &clock::Global,
855 ranges: &[Range<FullOffset>],
856 new_text: &[Arc<str>],
857 timestamp: InsertionTimestamp,
858 ) {
859 if ranges.is_empty() {
860 return;
861 }
862
863 let edits = ranges.iter().zip(new_text.iter());
864 let mut edits_patch = Patch::default();
865 let mut insertion_slices = Vec::new();
866 let cx = Some(version.clone());
867 let mut new_insertions = Vec::new();
868 let mut insertion_offset = 0;
869 let mut new_ropes =
870 RopeBuilder::new(self.visible_text.cursor(0), self.deleted_text.cursor(0));
871 let mut old_fragments = self.fragments.cursor::<(VersionedFullOffset, usize)>();
872 let mut new_fragments = old_fragments.slice(
873 &VersionedFullOffset::Offset(ranges[0].start),
874 Bias::Left,
875 &cx,
876 );
877 new_ropes.push_tree(new_fragments.summary().text);
878
879 let mut fragment_start = old_fragments.start().0.full_offset();
880 for (range, new_text) in edits {
881 let fragment_end = old_fragments.end(&cx).0.full_offset();
882
883 // If the current fragment ends before this range, then jump ahead to the first fragment
884 // that extends past the start of this range, reusing any intervening fragments.
885 if fragment_end < range.start {
886 // If the current fragment has been partially consumed, then consume the rest of it
887 // and advance to the next fragment before slicing.
888 if fragment_start > old_fragments.start().0.full_offset() {
889 if fragment_end > fragment_start {
890 let mut suffix = old_fragments.item().unwrap().clone();
891 suffix.len = fragment_end.0 - fragment_start.0;
892 suffix.insertion_offset +=
893 fragment_start - old_fragments.start().0.full_offset();
894 new_insertions.push(InsertionFragment::insert_new(&suffix));
895 new_ropes.push_fragment(&suffix, suffix.visible);
896 new_fragments.push(suffix, &None);
897 }
898 old_fragments.next(&cx);
899 }
900
901 let slice =
902 old_fragments.slice(&VersionedFullOffset::Offset(range.start), Bias::Left, &cx);
903 new_ropes.push_tree(slice.summary().text);
904 new_fragments.push_tree(slice, &None);
905 fragment_start = old_fragments.start().0.full_offset();
906 }
907
908 // If we are at the end of a non-concurrent fragment, advance to the next one.
909 let fragment_end = old_fragments.end(&cx).0.full_offset();
910 if fragment_end == range.start && fragment_end > fragment_start {
911 let mut fragment = old_fragments.item().unwrap().clone();
912 fragment.len = fragment_end.0 - fragment_start.0;
913 fragment.insertion_offset += fragment_start - old_fragments.start().0.full_offset();
914 new_insertions.push(InsertionFragment::insert_new(&fragment));
915 new_ropes.push_fragment(&fragment, fragment.visible);
916 new_fragments.push(fragment, &None);
917 old_fragments.next(&cx);
918 fragment_start = old_fragments.start().0.full_offset();
919 }
920
921 // Skip over insertions that are concurrent to this edit, but have a lower lamport
922 // timestamp.
923 while let Some(fragment) = old_fragments.item() {
924 if fragment_start == range.start
925 && fragment.insertion_timestamp.lamport() > timestamp.lamport()
926 {
927 new_ropes.push_fragment(fragment, fragment.visible);
928 new_fragments.push(fragment.clone(), &None);
929 old_fragments.next(&cx);
930 debug_assert_eq!(fragment_start, range.start);
931 } else {
932 break;
933 }
934 }
935 debug_assert!(fragment_start <= range.start);
936
937 // Preserve any portion of the current fragment that precedes this range.
938 if fragment_start < range.start {
939 let mut prefix = old_fragments.item().unwrap().clone();
940 prefix.len = range.start.0 - fragment_start.0;
941 prefix.insertion_offset += fragment_start - old_fragments.start().0.full_offset();
942 prefix.id = Locator::between(&new_fragments.summary().max_id, &prefix.id);
943 new_insertions.push(InsertionFragment::insert_new(&prefix));
944 fragment_start = range.start;
945 new_ropes.push_fragment(&prefix, prefix.visible);
946 new_fragments.push(prefix, &None);
947 }
948
949 // Insert the new text before any existing fragments within the range.
950 if !new_text.is_empty() {
951 let mut old_start = old_fragments.start().1;
952 if old_fragments.item().map_or(false, |f| f.visible) {
953 old_start += fragment_start.0 - old_fragments.start().0.full_offset().0;
954 }
955 let new_start = new_fragments.summary().text.visible;
956 let fragment = Fragment {
957 id: Locator::between(
958 &new_fragments.summary().max_id,
959 old_fragments
960 .item()
961 .map_or(&Locator::max(), |old_fragment| &old_fragment.id),
962 ),
963 insertion_timestamp: timestamp,
964 insertion_offset,
965 len: new_text.len(),
966 deletions: Default::default(),
967 max_undos: Default::default(),
968 visible: true,
969 };
970 edits_patch.push(Edit {
971 old: old_start..old_start,
972 new: new_start..new_start + new_text.len(),
973 });
974 insertion_slices.push(fragment.insertion_slice());
975 new_insertions.push(InsertionFragment::insert_new(&fragment));
976 new_ropes.push_str(new_text);
977 new_fragments.push(fragment, &None);
978 insertion_offset += new_text.len();
979 }
980
981 // Advance through every fragment that intersects this range, marking the intersecting
982 // portions as deleted.
983 while fragment_start < range.end {
984 let fragment = old_fragments.item().unwrap();
985 let fragment_end = old_fragments.end(&cx).0.full_offset();
986 let mut intersection = fragment.clone();
987 let intersection_end = cmp::min(range.end, fragment_end);
988 if fragment.was_visible(version, &self.undo_map) {
989 intersection.len = intersection_end.0 - fragment_start.0;
990 intersection.insertion_offset +=
991 fragment_start - old_fragments.start().0.full_offset();
992 intersection.id =
993 Locator::between(&new_fragments.summary().max_id, &intersection.id);
994 intersection.deletions.insert(timestamp.local());
995 intersection.visible = false;
996 insertion_slices.push(intersection.insertion_slice());
997 }
998 if intersection.len > 0 {
999 if fragment.visible && !intersection.visible {
1000 let old_start = old_fragments.start().1
1001 + (fragment_start.0 - old_fragments.start().0.full_offset().0);
1002 let new_start = new_fragments.summary().text.visible;
1003 edits_patch.push(Edit {
1004 old: old_start..old_start + intersection.len,
1005 new: new_start..new_start,
1006 });
1007 }
1008 new_insertions.push(InsertionFragment::insert_new(&intersection));
1009 new_ropes.push_fragment(&intersection, fragment.visible);
1010 new_fragments.push(intersection, &None);
1011 fragment_start = intersection_end;
1012 }
1013 if fragment_end <= range.end {
1014 old_fragments.next(&cx);
1015 }
1016 }
1017 }
1018
1019 // If the current fragment has been partially consumed, then consume the rest of it
1020 // and advance to the next fragment before slicing.
1021 if fragment_start > old_fragments.start().0.full_offset() {
1022 let fragment_end = old_fragments.end(&cx).0.full_offset();
1023 if fragment_end > fragment_start {
1024 let mut suffix = old_fragments.item().unwrap().clone();
1025 suffix.len = fragment_end.0 - fragment_start.0;
1026 suffix.insertion_offset += fragment_start - old_fragments.start().0.full_offset();
1027 new_insertions.push(InsertionFragment::insert_new(&suffix));
1028 new_ropes.push_fragment(&suffix, suffix.visible);
1029 new_fragments.push(suffix, &None);
1030 }
1031 old_fragments.next(&cx);
1032 }
1033
1034 let suffix = old_fragments.suffix(&cx);
1035 new_ropes.push_tree(suffix.summary().text);
1036 new_fragments.push_tree(suffix, &None);
1037 let (visible_text, deleted_text) = new_ropes.finish();
1038 drop(old_fragments);
1039
1040 self.snapshot.fragments = new_fragments;
1041 self.snapshot.visible_text = visible_text;
1042 self.snapshot.deleted_text = deleted_text;
1043 self.snapshot.insertions.edit(new_insertions, &());
1044 self.history
1045 .insertion_slices
1046 .insert(timestamp.local(), insertion_slices);
1047 self.subscriptions.publish_mut(&edits_patch)
1048 }
1049
1050 fn fragment_ids_for_edits<'a>(
1051 &'a self,
1052 edit_ids: impl Iterator<Item = &'a clock::Local>,
1053 ) -> Vec<&'a Locator> {
1054 // Get all of the insertion slices changed by the given edits.
1055 let mut insertion_slices = Vec::new();
1056 for edit_id in edit_ids {
1057 if let Some(slices) = self.history.insertion_slices.get(edit_id) {
1058 insertion_slices.extend_from_slice(slices)
1059 }
1060 }
1061 insertion_slices
1062 .sort_unstable_by_key(|s| (s.insertion_id, s.range.start, Reverse(s.range.end)));
1063
1064 // Get all of the fragments corresponding to these insertion slices.
1065 let mut fragment_ids = Vec::new();
1066 let mut insertions_cursor = self.insertions.cursor::<InsertionFragmentKey>();
1067 for insertion_slice in &insertion_slices {
1068 if insertion_slice.insertion_id != insertions_cursor.start().timestamp
1069 || insertion_slice.range.start > insertions_cursor.start().split_offset
1070 {
1071 insertions_cursor.seek_forward(
1072 &InsertionFragmentKey {
1073 timestamp: insertion_slice.insertion_id,
1074 split_offset: insertion_slice.range.start,
1075 },
1076 Bias::Left,
1077 &(),
1078 );
1079 }
1080 while let Some(item) = insertions_cursor.item() {
1081 if item.timestamp != insertion_slice.insertion_id
1082 || item.split_offset >= insertion_slice.range.end
1083 {
1084 break;
1085 }
1086 fragment_ids.push(&item.fragment_id);
1087 insertions_cursor.next(&());
1088 }
1089 }
1090 fragment_ids.sort_unstable();
1091 fragment_ids
1092 }
1093
1094 fn apply_undo(&mut self, undo: &UndoOperation) -> Result<()> {
1095 self.snapshot.undo_map.insert(undo);
1096
1097 let mut edits = Patch::default();
1098 let mut old_fragments = self.fragments.cursor::<(Option<&Locator>, usize)>();
1099 let mut new_fragments = SumTree::new();
1100 let mut new_ropes =
1101 RopeBuilder::new(self.visible_text.cursor(0), self.deleted_text.cursor(0));
1102
1103 for fragment_id in self.fragment_ids_for_edits(undo.counts.keys()) {
1104 let preceding_fragments = old_fragments.slice(&Some(fragment_id), Bias::Left, &None);
1105 new_ropes.push_tree(preceding_fragments.summary().text);
1106 new_fragments.push_tree(preceding_fragments, &None);
1107
1108 if let Some(fragment) = old_fragments.item() {
1109 let mut fragment = fragment.clone();
1110 let fragment_was_visible = fragment.visible;
1111
1112 if fragment.was_visible(&undo.transaction_version, &self.undo_map)
1113 || undo
1114 .counts
1115 .contains_key(&fragment.insertion_timestamp.local())
1116 {
1117 fragment.visible = fragment.is_visible(&self.undo_map);
1118 fragment.max_undos.observe(undo.id);
1119 }
1120
1121 let old_start = old_fragments.start().1;
1122 let new_start = new_fragments.summary().text.visible;
1123 if fragment_was_visible && !fragment.visible {
1124 edits.push(Edit {
1125 old: old_start..old_start + fragment.len,
1126 new: new_start..new_start,
1127 });
1128 } else if !fragment_was_visible && fragment.visible {
1129 edits.push(Edit {
1130 old: old_start..old_start,
1131 new: new_start..new_start + fragment.len,
1132 });
1133 }
1134 new_ropes.push_fragment(&fragment, fragment_was_visible);
1135 new_fragments.push(fragment, &None);
1136
1137 old_fragments.next(&None);
1138 }
1139 }
1140
1141 let suffix = old_fragments.suffix(&None);
1142 new_ropes.push_tree(suffix.summary().text);
1143 new_fragments.push_tree(suffix, &None);
1144
1145 drop(old_fragments);
1146 let (visible_text, deleted_text) = new_ropes.finish();
1147 self.snapshot.fragments = new_fragments;
1148 self.snapshot.visible_text = visible_text;
1149 self.snapshot.deleted_text = deleted_text;
1150 self.subscriptions.publish_mut(&edits);
1151 Ok(())
1152 }
1153
1154 fn flush_deferred_ops(&mut self) -> Result<()> {
1155 self.deferred_replicas.clear();
1156 let mut deferred_ops = Vec::new();
1157 for op in self.deferred_ops.drain().iter().cloned() {
1158 if self.can_apply_op(&op) {
1159 self.apply_op(op)?;
1160 } else {
1161 self.deferred_replicas.insert(op.replica_id());
1162 deferred_ops.push(op);
1163 }
1164 }
1165 self.deferred_ops.insert(deferred_ops);
1166 Ok(())
1167 }
1168
1169 fn can_apply_op(&self, op: &Operation) -> bool {
1170 if self.deferred_replicas.contains(&op.replica_id()) {
1171 false
1172 } else {
1173 match op {
1174 Operation::Edit(edit) => self.version.observed_all(&edit.version),
1175 Operation::Undo { undo, .. } => self.version.observed_all(&undo.version),
1176 }
1177 }
1178 }
1179
1180 pub fn peek_undo_stack(&self) -> Option<&HistoryEntry> {
1181 self.history.undo_stack.last()
1182 }
1183
1184 pub fn peek_redo_stack(&self) -> Option<&HistoryEntry> {
1185 self.history.redo_stack.last()
1186 }
1187
1188 pub fn start_transaction(&mut self) -> Option<TransactionId> {
1189 self.start_transaction_at(Instant::now())
1190 }
1191
1192 pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1193 self.history
1194 .start_transaction(self.version.clone(), now, &mut self.local_clock)
1195 }
1196
1197 pub fn end_transaction(&mut self) -> Option<(TransactionId, clock::Global)> {
1198 self.end_transaction_at(Instant::now())
1199 }
1200
1201 pub fn end_transaction_at(&mut self, now: Instant) -> Option<(TransactionId, clock::Global)> {
1202 if let Some(entry) = self.history.end_transaction(now) {
1203 let since = entry.transaction.start.clone();
1204 let id = self.history.group().unwrap();
1205 Some((id, since))
1206 } else {
1207 None
1208 }
1209 }
1210
1211 pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1212 self.history.finalize_last_transaction()
1213 }
1214
1215 pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
1216 self.history.group_until(transaction_id);
1217 }
1218
1219 pub fn base_text(&self) -> &Arc<str> {
1220 &self.history.base_text
1221 }
1222
1223 pub fn history(&self) -> impl Iterator<Item = &Operation> {
1224 self.history.operations.values()
1225 }
1226
1227 pub fn undo_history(&self) -> impl Iterator<Item = (&clock::Local, &[(clock::Local, u32)])> {
1228 self.undo_map
1229 .0
1230 .iter()
1231 .map(|(edit_id, undo_counts)| (edit_id, undo_counts.as_slice()))
1232 }
1233
1234 pub fn undo(&mut self) -> Option<(TransactionId, Operation)> {
1235 if let Some(entry) = self.history.pop_undo() {
1236 let transaction = entry.transaction.clone();
1237 let transaction_id = transaction.id;
1238 let op = self.undo_or_redo(transaction).unwrap();
1239 Some((transaction_id, op))
1240 } else {
1241 None
1242 }
1243 }
1244
1245 #[allow(clippy::needless_collect)]
1246 pub fn undo_to_transaction(&mut self, transaction_id: TransactionId) -> Vec<Operation> {
1247 let transactions = self
1248 .history
1249 .remove_from_undo(transaction_id)
1250 .iter()
1251 .map(|entry| entry.transaction.clone())
1252 .collect::<Vec<_>>();
1253
1254 transactions
1255 .into_iter()
1256 .map(|transaction| self.undo_or_redo(transaction).unwrap())
1257 .collect()
1258 }
1259
1260 pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1261 self.history.forget(transaction_id);
1262 }
1263
1264 pub fn redo(&mut self) -> Option<(TransactionId, Operation)> {
1265 if let Some(entry) = self.history.pop_redo() {
1266 let transaction = entry.transaction.clone();
1267 let transaction_id = transaction.id;
1268 let op = self.undo_or_redo(transaction).unwrap();
1269 Some((transaction_id, op))
1270 } else {
1271 None
1272 }
1273 }
1274
1275 #[allow(clippy::needless_collect)]
1276 pub fn redo_to_transaction(&mut self, transaction_id: TransactionId) -> Vec<Operation> {
1277 let transactions = self
1278 .history
1279 .remove_from_redo(transaction_id)
1280 .iter()
1281 .map(|entry| entry.transaction.clone())
1282 .collect::<Vec<_>>();
1283
1284 transactions
1285 .into_iter()
1286 .map(|transaction| self.undo_or_redo(transaction).unwrap())
1287 .collect()
1288 }
1289
1290 fn undo_or_redo(&mut self, transaction: Transaction) -> Result<Operation> {
1291 let mut counts = HashMap::default();
1292 for edit_id in transaction.edit_ids {
1293 counts.insert(edit_id, self.undo_map.undo_count(edit_id) + 1);
1294 }
1295
1296 let undo = UndoOperation {
1297 id: self.local_clock.tick(),
1298 version: self.version(),
1299 counts,
1300 transaction_version: transaction.start,
1301 };
1302 self.apply_undo(&undo)?;
1303 let operation = Operation::Undo {
1304 undo,
1305 lamport_timestamp: self.lamport_clock.tick(),
1306 };
1307 self.snapshot.version.observe(operation.local_timestamp());
1308 self.history.push(operation.clone());
1309 Ok(operation)
1310 }
1311
1312 pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
1313 self.history.push_transaction(transaction, now);
1314 self.history.finalize_last_transaction();
1315 }
1316
1317 pub fn edited_ranges_for_transaction<'a, D>(
1318 &'a self,
1319 transaction: &'a Transaction,
1320 ) -> impl 'a + Iterator<Item = Range<D>>
1321 where
1322 D: TextDimension,
1323 {
1324 // get fragment ranges
1325 let mut cursor = self.fragments.cursor::<(Option<&Locator>, usize)>();
1326 let offset_ranges = self
1327 .fragment_ids_for_edits(transaction.edit_ids.iter())
1328 .into_iter()
1329 .filter_map(move |fragment_id| {
1330 cursor.seek_forward(&Some(fragment_id), Bias::Left, &None);
1331 let fragment = cursor.item()?;
1332 let start_offset = cursor.start().1;
1333 let end_offset = start_offset + if fragment.visible { fragment.len } else { 0 };
1334 Some(start_offset..end_offset)
1335 });
1336
1337 // combine adjacent ranges
1338 let mut prev_range: Option<Range<usize>> = None;
1339 let disjoint_ranges = offset_ranges
1340 .map(Some)
1341 .chain([None])
1342 .filter_map(move |range| {
1343 if let Some((range, prev_range)) = range.as_ref().zip(prev_range.as_mut()) {
1344 if prev_range.end == range.start {
1345 prev_range.end = range.end;
1346 return None;
1347 }
1348 }
1349 let result = prev_range.clone();
1350 prev_range = range;
1351 result
1352 });
1353
1354 // convert to the desired text dimension.
1355 let mut position = D::default();
1356 let mut rope_cursor = self.visible_text.cursor(0);
1357 disjoint_ranges.map(move |range| {
1358 position.add_assign(&rope_cursor.summary(range.start));
1359 let start = position.clone();
1360 position.add_assign(&rope_cursor.summary(range.end));
1361 let end = position.clone();
1362 start..end
1363 })
1364 }
1365
1366 pub fn subscribe(&mut self) -> Subscription {
1367 self.subscriptions.subscribe()
1368 }
1369
1370 pub fn wait_for_edits(
1371 &mut self,
1372 edit_ids: impl IntoIterator<Item = clock::Local>,
1373 ) -> impl 'static + Future<Output = ()> {
1374 let mut futures = Vec::new();
1375 for edit_id in edit_ids {
1376 if !self.version.observed(edit_id) {
1377 let (tx, rx) = oneshot::channel();
1378 self.edit_id_resolvers.entry(edit_id).or_default().push(tx);
1379 futures.push(rx);
1380 }
1381 }
1382
1383 async move {
1384 for mut future in futures {
1385 future.recv().await;
1386 }
1387 }
1388 }
1389
1390 pub fn wait_for_anchors<'a>(
1391 &mut self,
1392 anchors: impl IntoIterator<Item = &'a Anchor>,
1393 ) -> impl 'static + Future<Output = ()> {
1394 let mut futures = Vec::new();
1395 for anchor in anchors {
1396 if !self.version.observed(anchor.timestamp)
1397 && *anchor != Anchor::MAX
1398 && *anchor != Anchor::MIN
1399 {
1400 let (tx, rx) = oneshot::channel();
1401 self.edit_id_resolvers
1402 .entry(anchor.timestamp)
1403 .or_default()
1404 .push(tx);
1405 futures.push(rx);
1406 }
1407 }
1408
1409 async move {
1410 for mut future in futures {
1411 future.recv().await;
1412 }
1413 }
1414 }
1415
1416 pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = ()> {
1417 let (tx, mut rx) = barrier::channel();
1418 if !self.snapshot.version.observed_all(&version) {
1419 self.version_barriers.push((version, tx));
1420 }
1421 async move {
1422 rx.recv().await;
1423 }
1424 }
1425
1426 fn resolve_edit(&mut self, edit_id: clock::Local) {
1427 for mut tx in self
1428 .edit_id_resolvers
1429 .remove(&edit_id)
1430 .into_iter()
1431 .flatten()
1432 {
1433 let _ = tx.try_send(());
1434 }
1435 }
1436}
1437
1438#[cfg(any(test, feature = "test-support"))]
1439impl Buffer {
1440 pub fn check_invariants(&self) {
1441 // Ensure every fragment is ordered by locator in the fragment tree and corresponds
1442 // to an insertion fragment in the insertions tree.
1443 let mut prev_fragment_id = Locator::min();
1444 for fragment in self.snapshot.fragments.items(&None) {
1445 assert!(fragment.id > prev_fragment_id);
1446 prev_fragment_id = fragment.id.clone();
1447
1448 let insertion_fragment = self
1449 .snapshot
1450 .insertions
1451 .get(
1452 &InsertionFragmentKey {
1453 timestamp: fragment.insertion_timestamp.local(),
1454 split_offset: fragment.insertion_offset,
1455 },
1456 &(),
1457 )
1458 .unwrap();
1459 assert_eq!(
1460 insertion_fragment.fragment_id, fragment.id,
1461 "fragment: {:?}\ninsertion: {:?}",
1462 fragment, insertion_fragment
1463 );
1464 }
1465
1466 let mut cursor = self.snapshot.fragments.cursor::<Option<&Locator>>();
1467 for insertion_fragment in self.snapshot.insertions.cursor::<()>() {
1468 cursor.seek(&Some(&insertion_fragment.fragment_id), Bias::Left, &None);
1469 let fragment = cursor.item().unwrap();
1470 assert_eq!(insertion_fragment.fragment_id, fragment.id);
1471 assert_eq!(insertion_fragment.split_offset, fragment.insertion_offset);
1472 }
1473
1474 let fragment_summary = self.snapshot.fragments.summary();
1475 assert_eq!(
1476 fragment_summary.text.visible,
1477 self.snapshot.visible_text.len()
1478 );
1479 assert_eq!(
1480 fragment_summary.text.deleted,
1481 self.snapshot.deleted_text.len()
1482 );
1483
1484 assert!(!self.text().contains("\r\n"));
1485 }
1486
1487 pub fn set_group_interval(&mut self, group_interval: Duration) {
1488 self.history.group_interval = group_interval;
1489 }
1490
1491 pub fn random_byte_range(&self, start_offset: usize, rng: &mut impl rand::Rng) -> Range<usize> {
1492 let end = self.clip_offset(rng.gen_range(start_offset..=self.len()), Bias::Right);
1493 let start = self.clip_offset(rng.gen_range(start_offset..=end), Bias::Right);
1494 start..end
1495 }
1496
1497 #[allow(clippy::type_complexity)]
1498 pub fn randomly_edit<T>(
1499 &mut self,
1500 rng: &mut T,
1501 edit_count: usize,
1502 ) -> (Vec<(Range<usize>, Arc<str>)>, Operation)
1503 where
1504 T: rand::Rng,
1505 {
1506 let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
1507 let mut last_end = None;
1508 for _ in 0..edit_count {
1509 if last_end.map_or(false, |last_end| last_end >= self.len()) {
1510 break;
1511 }
1512 let new_start = last_end.map_or(0, |last_end| last_end + 1);
1513 let range = self.random_byte_range(new_start, rng);
1514 last_end = Some(range.end);
1515
1516 let new_text_len = rng.gen_range(0..10);
1517 let new_text: String = crate::random_char_iter::RandomCharIter::new(&mut *rng)
1518 .take(new_text_len)
1519 .collect();
1520
1521 edits.push((range, new_text.into()));
1522 }
1523
1524 log::info!("mutating buffer {} with {:?}", self.replica_id, edits);
1525 let op = self.edit(edits.iter().cloned());
1526 if let Operation::Edit(edit) = &op {
1527 assert_eq!(edits.len(), edit.new_text.len());
1528 for (edit, new_text) in edits.iter_mut().zip(&edit.new_text) {
1529 edit.1 = new_text.clone();
1530 }
1531 } else {
1532 unreachable!()
1533 }
1534
1535 (edits, op)
1536 }
1537
1538 pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng) -> Vec<Operation> {
1539 use rand::prelude::*;
1540
1541 let mut ops = Vec::new();
1542 for _ in 0..rng.gen_range(1..=5) {
1543 if let Some(entry) = self.history.undo_stack.choose(rng) {
1544 let transaction = entry.transaction.clone();
1545 log::info!(
1546 "undoing buffer {} transaction {:?}",
1547 self.replica_id,
1548 transaction
1549 );
1550 ops.push(self.undo_or_redo(transaction).unwrap());
1551 }
1552 }
1553 ops
1554 }
1555}
1556
1557impl Deref for Buffer {
1558 type Target = BufferSnapshot;
1559
1560 fn deref(&self) -> &Self::Target {
1561 &self.snapshot
1562 }
1563}
1564
1565impl BufferSnapshot {
1566 pub fn as_rope(&self) -> &Rope {
1567 &self.visible_text
1568 }
1569
1570 pub fn replica_id(&self) -> ReplicaId {
1571 self.replica_id
1572 }
1573
1574 pub fn row_count(&self) -> u32 {
1575 self.max_point().row + 1
1576 }
1577
1578 pub fn len(&self) -> usize {
1579 self.visible_text.len()
1580 }
1581
1582 pub fn is_empty(&self) -> bool {
1583 self.len() == 0
1584 }
1585
1586 pub fn chars(&self) -> impl Iterator<Item = char> + '_ {
1587 self.chars_at(0)
1588 }
1589
1590 pub fn chars_for_range<T: ToOffset>(&self, range: Range<T>) -> impl Iterator<Item = char> + '_ {
1591 self.text_for_range(range).flat_map(str::chars)
1592 }
1593
1594 pub fn contains_str_at<T>(&self, position: T, needle: &str) -> bool
1595 where
1596 T: ToOffset,
1597 {
1598 let position = position.to_offset(self);
1599 position == self.clip_offset(position, Bias::Left)
1600 && self
1601 .bytes_in_range(position..self.len())
1602 .flatten()
1603 .copied()
1604 .take(needle.len())
1605 .eq(needle.bytes())
1606 }
1607
1608 pub fn common_prefix_at<T>(&self, position: T, needle: &str) -> Range<T>
1609 where
1610 T: ToOffset + TextDimension,
1611 {
1612 let offset = position.to_offset(self);
1613 let common_prefix_len = needle
1614 .char_indices()
1615 .map(|(index, _)| index)
1616 .chain([needle.len()])
1617 .take_while(|&len| len <= offset)
1618 .filter(|&len| {
1619 let left = self
1620 .chars_for_range(offset - len..offset)
1621 .flat_map(char::to_lowercase);
1622 let right = needle[..len].chars().flat_map(char::to_lowercase);
1623 left.eq(right)
1624 })
1625 .last()
1626 .unwrap_or(0);
1627 let start_offset = offset - common_prefix_len;
1628 let start = self.text_summary_for_range(0..start_offset);
1629 start..position
1630 }
1631
1632 pub fn text(&self) -> String {
1633 self.visible_text.to_string()
1634 }
1635
1636 pub fn line_ending(&self) -> LineEnding {
1637 self.line_ending
1638 }
1639
1640 pub fn deleted_text(&self) -> String {
1641 self.deleted_text.to_string()
1642 }
1643
1644 pub fn fragments(&self) -> impl Iterator<Item = &Fragment> {
1645 self.fragments.iter()
1646 }
1647
1648 pub fn text_summary(&self) -> TextSummary {
1649 self.visible_text.summary()
1650 }
1651
1652 pub fn max_point(&self) -> Point {
1653 self.visible_text.max_point()
1654 }
1655
1656 pub fn max_point_utf16(&self) -> PointUtf16 {
1657 self.visible_text.max_point_utf16()
1658 }
1659
1660 pub fn point_to_offset(&self, point: Point) -> usize {
1661 self.visible_text.point_to_offset(point)
1662 }
1663
1664 pub fn point_utf16_to_offset(&self, point: PointUtf16) -> usize {
1665 self.visible_text.point_utf16_to_offset(point)
1666 }
1667
1668 pub fn point_utf16_to_point(&self, point: PointUtf16) -> Point {
1669 self.visible_text.point_utf16_to_point(point)
1670 }
1671
1672 pub fn offset_utf16_to_offset(&self, offset: OffsetUtf16) -> usize {
1673 self.visible_text.offset_utf16_to_offset(offset)
1674 }
1675
1676 pub fn offset_to_offset_utf16(&self, offset: usize) -> OffsetUtf16 {
1677 self.visible_text.offset_to_offset_utf16(offset)
1678 }
1679
1680 pub fn offset_to_point(&self, offset: usize) -> Point {
1681 self.visible_text.offset_to_point(offset)
1682 }
1683
1684 pub fn offset_to_point_utf16(&self, offset: usize) -> PointUtf16 {
1685 self.visible_text.offset_to_point_utf16(offset)
1686 }
1687
1688 pub fn point_to_point_utf16(&self, point: Point) -> PointUtf16 {
1689 self.visible_text.point_to_point_utf16(point)
1690 }
1691
1692 pub fn version(&self) -> &clock::Global {
1693 &self.version
1694 }
1695
1696 pub fn chars_at<T: ToOffset>(&self, position: T) -> impl Iterator<Item = char> + '_ {
1697 let offset = position.to_offset(self);
1698 self.visible_text.chars_at(offset)
1699 }
1700
1701 pub fn reversed_chars_at<T: ToOffset>(&self, position: T) -> impl Iterator<Item = char> + '_ {
1702 let offset = position.to_offset(self);
1703 self.visible_text.reversed_chars_at(offset)
1704 }
1705
1706 pub fn reversed_chunks_in_range<T: ToOffset>(&self, range: Range<T>) -> rope::Chunks {
1707 let range = range.start.to_offset(self)..range.end.to_offset(self);
1708 self.visible_text.reversed_chunks_in_range(range)
1709 }
1710
1711 pub fn bytes_in_range<T: ToOffset>(&self, range: Range<T>) -> rope::Bytes<'_> {
1712 let start = range.start.to_offset(self);
1713 let end = range.end.to_offset(self);
1714 self.visible_text.bytes_in_range(start..end)
1715 }
1716
1717 pub fn text_for_range<T: ToOffset>(&self, range: Range<T>) -> Chunks<'_> {
1718 let start = range.start.to_offset(self);
1719 let end = range.end.to_offset(self);
1720 self.visible_text.chunks_in_range(start..end)
1721 }
1722
1723 pub fn line_len(&self, row: u32) -> u32 {
1724 let row_start_offset = Point::new(row, 0).to_offset(self);
1725 let row_end_offset = if row >= self.max_point().row {
1726 self.len()
1727 } else {
1728 Point::new(row + 1, 0).to_offset(self) - 1
1729 };
1730 (row_end_offset - row_start_offset) as u32
1731 }
1732
1733 pub fn is_line_blank(&self, row: u32) -> bool {
1734 self.text_for_range(Point::new(row, 0)..Point::new(row, self.line_len(row)))
1735 .all(|chunk| chunk.matches(|c: char| !c.is_whitespace()).next().is_none())
1736 }
1737
1738 pub fn text_summary_for_range<D, O: ToOffset>(&self, range: Range<O>) -> D
1739 where
1740 D: TextDimension,
1741 {
1742 self.visible_text
1743 .cursor(range.start.to_offset(self))
1744 .summary(range.end.to_offset(self))
1745 }
1746
1747 pub fn summaries_for_anchors<'a, D, A>(&'a self, anchors: A) -> impl 'a + Iterator<Item = D>
1748 where
1749 D: 'a + TextDimension,
1750 A: 'a + IntoIterator<Item = &'a Anchor>,
1751 {
1752 let anchors = anchors.into_iter();
1753 let mut insertion_cursor = self.insertions.cursor::<InsertionFragmentKey>();
1754 let mut fragment_cursor = self.fragments.cursor::<(Option<&Locator>, usize)>();
1755 let mut text_cursor = self.visible_text.cursor(0);
1756 let mut position = D::default();
1757
1758 anchors.map(move |anchor| {
1759 if *anchor == Anchor::MIN {
1760 return D::default();
1761 } else if *anchor == Anchor::MAX {
1762 return D::from_text_summary(&self.visible_text.summary());
1763 }
1764
1765 let anchor_key = InsertionFragmentKey {
1766 timestamp: anchor.timestamp,
1767 split_offset: anchor.offset,
1768 };
1769 insertion_cursor.seek(&anchor_key, anchor.bias, &());
1770 if let Some(insertion) = insertion_cursor.item() {
1771 let comparison = sum_tree::KeyedItem::key(insertion).cmp(&anchor_key);
1772 if comparison == Ordering::Greater
1773 || (anchor.bias == Bias::Left
1774 && comparison == Ordering::Equal
1775 && anchor.offset > 0)
1776 {
1777 insertion_cursor.prev(&());
1778 }
1779 } else {
1780 insertion_cursor.prev(&());
1781 }
1782 let insertion = insertion_cursor.item().expect("invalid insertion");
1783 assert_eq!(insertion.timestamp, anchor.timestamp, "invalid insertion");
1784
1785 fragment_cursor.seek_forward(&Some(&insertion.fragment_id), Bias::Left, &None);
1786 let fragment = fragment_cursor.item().unwrap();
1787 let mut fragment_offset = fragment_cursor.start().1;
1788 if fragment.visible {
1789 fragment_offset += anchor.offset - insertion.split_offset;
1790 }
1791
1792 position.add_assign(&text_cursor.summary(fragment_offset));
1793 position.clone()
1794 })
1795 }
1796
1797 fn summary_for_anchor<D>(&self, anchor: &Anchor) -> D
1798 where
1799 D: TextDimension,
1800 {
1801 if *anchor == Anchor::MIN {
1802 D::default()
1803 } else if *anchor == Anchor::MAX {
1804 D::from_text_summary(&self.visible_text.summary())
1805 } else {
1806 let anchor_key = InsertionFragmentKey {
1807 timestamp: anchor.timestamp,
1808 split_offset: anchor.offset,
1809 };
1810 let mut insertion_cursor = self.insertions.cursor::<InsertionFragmentKey>();
1811 insertion_cursor.seek(&anchor_key, anchor.bias, &());
1812 if let Some(insertion) = insertion_cursor.item() {
1813 let comparison = sum_tree::KeyedItem::key(insertion).cmp(&anchor_key);
1814 if comparison == Ordering::Greater
1815 || (anchor.bias == Bias::Left
1816 && comparison == Ordering::Equal
1817 && anchor.offset > 0)
1818 {
1819 insertion_cursor.prev(&());
1820 }
1821 } else {
1822 insertion_cursor.prev(&());
1823 }
1824 let insertion = insertion_cursor.item().expect("invalid insertion");
1825 assert_eq!(insertion.timestamp, anchor.timestamp, "invalid insertion");
1826
1827 let mut fragment_cursor = self.fragments.cursor::<(Option<&Locator>, usize)>();
1828 fragment_cursor.seek(&Some(&insertion.fragment_id), Bias::Left, &None);
1829 let fragment = fragment_cursor.item().unwrap();
1830 let mut fragment_offset = fragment_cursor.start().1;
1831 if fragment.visible {
1832 fragment_offset += anchor.offset - insertion.split_offset;
1833 }
1834 self.text_summary_for_range(0..fragment_offset)
1835 }
1836 }
1837
1838 fn fragment_id_for_anchor(&self, anchor: &Anchor) -> &Locator {
1839 if *anchor == Anchor::MIN {
1840 &locator::MIN
1841 } else if *anchor == Anchor::MAX {
1842 &locator::MAX
1843 } else {
1844 let anchor_key = InsertionFragmentKey {
1845 timestamp: anchor.timestamp,
1846 split_offset: anchor.offset,
1847 };
1848 let mut insertion_cursor = self.insertions.cursor::<InsertionFragmentKey>();
1849 insertion_cursor.seek(&anchor_key, anchor.bias, &());
1850 if let Some(insertion) = insertion_cursor.item() {
1851 let comparison = sum_tree::KeyedItem::key(insertion).cmp(&anchor_key);
1852 if comparison == Ordering::Greater
1853 || (anchor.bias == Bias::Left
1854 && comparison == Ordering::Equal
1855 && anchor.offset > 0)
1856 {
1857 insertion_cursor.prev(&());
1858 }
1859 } else {
1860 insertion_cursor.prev(&());
1861 }
1862 let insertion = insertion_cursor.item().expect("invalid insertion");
1863 debug_assert_eq!(insertion.timestamp, anchor.timestamp, "invalid insertion");
1864 &insertion.fragment_id
1865 }
1866 }
1867
1868 pub fn anchor_before<T: ToOffset>(&self, position: T) -> Anchor {
1869 self.anchor_at(position, Bias::Left)
1870 }
1871
1872 pub fn anchor_after<T: ToOffset>(&self, position: T) -> Anchor {
1873 self.anchor_at(position, Bias::Right)
1874 }
1875
1876 pub fn anchor_at<T: ToOffset>(&self, position: T, bias: Bias) -> Anchor {
1877 let offset = position.to_offset(self);
1878 if bias == Bias::Left && offset == 0 {
1879 Anchor::MIN
1880 } else if bias == Bias::Right && offset == self.len() {
1881 Anchor::MAX
1882 } else {
1883 let mut fragment_cursor = self.fragments.cursor::<usize>();
1884 fragment_cursor.seek(&offset, bias, &None);
1885 let fragment = fragment_cursor.item().unwrap();
1886 let overshoot = offset - *fragment_cursor.start();
1887 Anchor {
1888 timestamp: fragment.insertion_timestamp.local(),
1889 offset: fragment.insertion_offset + overshoot,
1890 bias,
1891 buffer_id: Some(self.remote_id),
1892 }
1893 }
1894 }
1895
1896 pub fn can_resolve(&self, anchor: &Anchor) -> bool {
1897 *anchor == Anchor::MIN
1898 || *anchor == Anchor::MAX
1899 || (Some(self.remote_id) == anchor.buffer_id && self.version.observed(anchor.timestamp))
1900 }
1901
1902 pub fn clip_offset(&self, offset: usize, bias: Bias) -> usize {
1903 self.visible_text.clip_offset(offset, bias)
1904 }
1905
1906 pub fn clip_point(&self, point: Point, bias: Bias) -> Point {
1907 self.visible_text.clip_point(point, bias)
1908 }
1909
1910 pub fn clip_offset_utf16(&self, offset: OffsetUtf16, bias: Bias) -> OffsetUtf16 {
1911 self.visible_text.clip_offset_utf16(offset, bias)
1912 }
1913
1914 pub fn clip_point_utf16(&self, point: PointUtf16, bias: Bias) -> PointUtf16 {
1915 self.visible_text.clip_point_utf16(point, bias)
1916 }
1917
1918 pub fn edits_since<'a, D>(
1919 &'a self,
1920 since: &'a clock::Global,
1921 ) -> impl 'a + Iterator<Item = Edit<D>>
1922 where
1923 D: TextDimension + Ord,
1924 {
1925 self.edits_since_in_range(since, Anchor::MIN..Anchor::MAX)
1926 }
1927
1928 pub fn edits_since_in_range<'a, D>(
1929 &'a self,
1930 since: &'a clock::Global,
1931 range: Range<Anchor>,
1932 ) -> impl 'a + Iterator<Item = Edit<D>>
1933 where
1934 D: TextDimension + Ord,
1935 {
1936 let fragments_cursor = if *since == self.version {
1937 None
1938 } else {
1939 let mut cursor = self
1940 .fragments
1941 .filter(move |summary| !since.observed_all(&summary.max_version));
1942 cursor.next(&None);
1943 Some(cursor)
1944 };
1945 let mut cursor = self
1946 .fragments
1947 .cursor::<(Option<&Locator>, FragmentTextSummary)>();
1948
1949 let start_fragment_id = self.fragment_id_for_anchor(&range.start);
1950 cursor.seek(&Some(start_fragment_id), Bias::Left, &None);
1951 let mut visible_start = cursor.start().1.visible;
1952 let mut deleted_start = cursor.start().1.deleted;
1953 if let Some(fragment) = cursor.item() {
1954 let overshoot = range.start.offset - fragment.insertion_offset;
1955 if fragment.visible {
1956 visible_start += overshoot;
1957 } else {
1958 deleted_start += overshoot;
1959 }
1960 }
1961 let end_fragment_id = self.fragment_id_for_anchor(&range.end);
1962
1963 Edits {
1964 visible_cursor: self.visible_text.cursor(visible_start),
1965 deleted_cursor: self.deleted_text.cursor(deleted_start),
1966 fragments_cursor,
1967 undos: &self.undo_map,
1968 since,
1969 old_end: Default::default(),
1970 new_end: Default::default(),
1971 range: (start_fragment_id, range.start.offset)..(end_fragment_id, range.end.offset),
1972 }
1973 }
1974}
1975
1976struct RopeBuilder<'a> {
1977 old_visible_cursor: rope::Cursor<'a>,
1978 old_deleted_cursor: rope::Cursor<'a>,
1979 new_visible: Rope,
1980 new_deleted: Rope,
1981}
1982
1983impl<'a> RopeBuilder<'a> {
1984 fn new(old_visible_cursor: rope::Cursor<'a>, old_deleted_cursor: rope::Cursor<'a>) -> Self {
1985 Self {
1986 old_visible_cursor,
1987 old_deleted_cursor,
1988 new_visible: Rope::new(),
1989 new_deleted: Rope::new(),
1990 }
1991 }
1992
1993 fn push_tree(&mut self, len: FragmentTextSummary) {
1994 self.push(len.visible, true, true);
1995 self.push(len.deleted, false, false);
1996 }
1997
1998 fn push_fragment(&mut self, fragment: &Fragment, was_visible: bool) {
1999 debug_assert!(fragment.len > 0);
2000 self.push(fragment.len, was_visible, fragment.visible)
2001 }
2002
2003 fn push(&mut self, len: usize, was_visible: bool, is_visible: bool) {
2004 let text = if was_visible {
2005 self.old_visible_cursor
2006 .slice(self.old_visible_cursor.offset() + len)
2007 } else {
2008 self.old_deleted_cursor
2009 .slice(self.old_deleted_cursor.offset() + len)
2010 };
2011 if is_visible {
2012 self.new_visible.append(text);
2013 } else {
2014 self.new_deleted.append(text);
2015 }
2016 }
2017
2018 fn push_str(&mut self, text: &str) {
2019 self.new_visible.push(text);
2020 }
2021
2022 fn finish(mut self) -> (Rope, Rope) {
2023 self.new_visible.append(self.old_visible_cursor.suffix());
2024 self.new_deleted.append(self.old_deleted_cursor.suffix());
2025 (self.new_visible, self.new_deleted)
2026 }
2027}
2028
2029impl<'a, D: TextDimension + Ord, F: FnMut(&FragmentSummary) -> bool> Iterator for Edits<'a, D, F> {
2030 type Item = Edit<D>;
2031
2032 fn next(&mut self) -> Option<Self::Item> {
2033 let mut pending_edit: Option<Edit<D>> = None;
2034 let cursor = self.fragments_cursor.as_mut()?;
2035
2036 while let Some(fragment) = cursor.item() {
2037 if fragment.id < *self.range.start.0 {
2038 cursor.next(&None);
2039 continue;
2040 } else if fragment.id > *self.range.end.0 {
2041 break;
2042 }
2043
2044 if cursor.start().visible > self.visible_cursor.offset() {
2045 let summary = self.visible_cursor.summary(cursor.start().visible);
2046 self.old_end.add_assign(&summary);
2047 self.new_end.add_assign(&summary);
2048 }
2049
2050 if pending_edit
2051 .as_ref()
2052 .map_or(false, |change| change.new.end < self.new_end)
2053 {
2054 break;
2055 }
2056
2057 if !fragment.was_visible(self.since, self.undos) && fragment.visible {
2058 let mut visible_end = cursor.end(&None).visible;
2059 if fragment.id == *self.range.end.0 {
2060 visible_end = cmp::min(
2061 visible_end,
2062 cursor.start().visible + (self.range.end.1 - fragment.insertion_offset),
2063 );
2064 }
2065
2066 let fragment_summary = self.visible_cursor.summary(visible_end);
2067 let mut new_end = self.new_end.clone();
2068 new_end.add_assign(&fragment_summary);
2069 if let Some(pending_edit) = pending_edit.as_mut() {
2070 pending_edit.new.end = new_end.clone();
2071 } else {
2072 pending_edit = Some(Edit {
2073 old: self.old_end.clone()..self.old_end.clone(),
2074 new: self.new_end.clone()..new_end.clone(),
2075 });
2076 }
2077
2078 self.new_end = new_end;
2079 } else if fragment.was_visible(self.since, self.undos) && !fragment.visible {
2080 let mut deleted_end = cursor.end(&None).deleted;
2081 if fragment.id == *self.range.end.0 {
2082 deleted_end = cmp::min(
2083 deleted_end,
2084 cursor.start().deleted + (self.range.end.1 - fragment.insertion_offset),
2085 );
2086 }
2087
2088 if cursor.start().deleted > self.deleted_cursor.offset() {
2089 self.deleted_cursor.seek_forward(cursor.start().deleted);
2090 }
2091 let fragment_summary = self.deleted_cursor.summary(deleted_end);
2092 let mut old_end = self.old_end.clone();
2093 old_end.add_assign(&fragment_summary);
2094 if let Some(pending_edit) = pending_edit.as_mut() {
2095 pending_edit.old.end = old_end.clone();
2096 } else {
2097 pending_edit = Some(Edit {
2098 old: self.old_end.clone()..old_end.clone(),
2099 new: self.new_end.clone()..self.new_end.clone(),
2100 });
2101 }
2102
2103 self.old_end = old_end;
2104 }
2105
2106 cursor.next(&None);
2107 }
2108
2109 pending_edit
2110 }
2111}
2112
2113impl Fragment {
2114 fn insertion_slice(&self) -> InsertionSlice {
2115 InsertionSlice {
2116 insertion_id: self.insertion_timestamp.local(),
2117 range: self.insertion_offset..self.insertion_offset + self.len,
2118 }
2119 }
2120
2121 fn is_visible(&self, undos: &UndoMap) -> bool {
2122 !undos.is_undone(self.insertion_timestamp.local())
2123 && self.deletions.iter().all(|d| undos.is_undone(*d))
2124 }
2125
2126 fn was_visible(&self, version: &clock::Global, undos: &UndoMap) -> bool {
2127 (version.observed(self.insertion_timestamp.local())
2128 && !undos.was_undone(self.insertion_timestamp.local(), version))
2129 && self
2130 .deletions
2131 .iter()
2132 .all(|d| !version.observed(*d) || undos.was_undone(*d, version))
2133 }
2134}
2135
2136impl sum_tree::Item for Fragment {
2137 type Summary = FragmentSummary;
2138
2139 fn summary(&self) -> Self::Summary {
2140 let mut max_version = clock::Global::new();
2141 max_version.observe(self.insertion_timestamp.local());
2142 for deletion in &self.deletions {
2143 max_version.observe(*deletion);
2144 }
2145 max_version.join(&self.max_undos);
2146
2147 let mut min_insertion_version = clock::Global::new();
2148 min_insertion_version.observe(self.insertion_timestamp.local());
2149 let max_insertion_version = min_insertion_version.clone();
2150 if self.visible {
2151 FragmentSummary {
2152 max_id: self.id.clone(),
2153 text: FragmentTextSummary {
2154 visible: self.len,
2155 deleted: 0,
2156 },
2157 max_version,
2158 min_insertion_version,
2159 max_insertion_version,
2160 }
2161 } else {
2162 FragmentSummary {
2163 max_id: self.id.clone(),
2164 text: FragmentTextSummary {
2165 visible: 0,
2166 deleted: self.len,
2167 },
2168 max_version,
2169 min_insertion_version,
2170 max_insertion_version,
2171 }
2172 }
2173 }
2174}
2175
2176impl sum_tree::Summary for FragmentSummary {
2177 type Context = Option<clock::Global>;
2178
2179 fn add_summary(&mut self, other: &Self, _: &Self::Context) {
2180 self.max_id.assign(&other.max_id);
2181 self.text.visible += &other.text.visible;
2182 self.text.deleted += &other.text.deleted;
2183 self.max_version.join(&other.max_version);
2184 self.min_insertion_version
2185 .meet(&other.min_insertion_version);
2186 self.max_insertion_version
2187 .join(&other.max_insertion_version);
2188 }
2189}
2190
2191impl Default for FragmentSummary {
2192 fn default() -> Self {
2193 FragmentSummary {
2194 max_id: Locator::min(),
2195 text: FragmentTextSummary::default(),
2196 max_version: clock::Global::new(),
2197 min_insertion_version: clock::Global::new(),
2198 max_insertion_version: clock::Global::new(),
2199 }
2200 }
2201}
2202
2203impl sum_tree::Item for InsertionFragment {
2204 type Summary = InsertionFragmentKey;
2205
2206 fn summary(&self) -> Self::Summary {
2207 InsertionFragmentKey {
2208 timestamp: self.timestamp,
2209 split_offset: self.split_offset,
2210 }
2211 }
2212}
2213
2214impl sum_tree::KeyedItem for InsertionFragment {
2215 type Key = InsertionFragmentKey;
2216
2217 fn key(&self) -> Self::Key {
2218 sum_tree::Item::summary(self)
2219 }
2220}
2221
2222impl InsertionFragment {
2223 fn new(fragment: &Fragment) -> Self {
2224 Self {
2225 timestamp: fragment.insertion_timestamp.local(),
2226 split_offset: fragment.insertion_offset,
2227 fragment_id: fragment.id.clone(),
2228 }
2229 }
2230
2231 fn insert_new(fragment: &Fragment) -> sum_tree::Edit<Self> {
2232 sum_tree::Edit::Insert(Self::new(fragment))
2233 }
2234}
2235
2236impl sum_tree::Summary for InsertionFragmentKey {
2237 type Context = ();
2238
2239 fn add_summary(&mut self, summary: &Self, _: &()) {
2240 *self = *summary;
2241 }
2242}
2243
2244#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
2245pub struct FullOffset(pub usize);
2246
2247impl ops::AddAssign<usize> for FullOffset {
2248 fn add_assign(&mut self, rhs: usize) {
2249 self.0 += rhs;
2250 }
2251}
2252
2253impl ops::Add<usize> for FullOffset {
2254 type Output = Self;
2255
2256 fn add(mut self, rhs: usize) -> Self::Output {
2257 self += rhs;
2258 self
2259 }
2260}
2261
2262impl ops::Sub for FullOffset {
2263 type Output = usize;
2264
2265 fn sub(self, rhs: Self) -> Self::Output {
2266 self.0 - rhs.0
2267 }
2268}
2269
2270impl<'a> sum_tree::Dimension<'a, FragmentSummary> for usize {
2271 fn add_summary(&mut self, summary: &FragmentSummary, _: &Option<clock::Global>) {
2272 *self += summary.text.visible;
2273 }
2274}
2275
2276impl<'a> sum_tree::Dimension<'a, FragmentSummary> for FullOffset {
2277 fn add_summary(&mut self, summary: &FragmentSummary, _: &Option<clock::Global>) {
2278 self.0 += summary.text.visible + summary.text.deleted;
2279 }
2280}
2281
2282impl<'a> sum_tree::Dimension<'a, FragmentSummary> for Option<&'a Locator> {
2283 fn add_summary(&mut self, summary: &'a FragmentSummary, _: &Option<clock::Global>) {
2284 *self = Some(&summary.max_id);
2285 }
2286}
2287
2288impl<'a> sum_tree::SeekTarget<'a, FragmentSummary, FragmentTextSummary> for usize {
2289 fn cmp(
2290 &self,
2291 cursor_location: &FragmentTextSummary,
2292 _: &Option<clock::Global>,
2293 ) -> cmp::Ordering {
2294 Ord::cmp(self, &cursor_location.visible)
2295 }
2296}
2297
2298#[derive(Copy, Clone, Debug, Eq, PartialEq)]
2299enum VersionedFullOffset {
2300 Offset(FullOffset),
2301 Invalid,
2302}
2303
2304impl VersionedFullOffset {
2305 fn full_offset(&self) -> FullOffset {
2306 if let Self::Offset(position) = self {
2307 *position
2308 } else {
2309 panic!("invalid version")
2310 }
2311 }
2312}
2313
2314impl Default for VersionedFullOffset {
2315 fn default() -> Self {
2316 Self::Offset(Default::default())
2317 }
2318}
2319
2320impl<'a> sum_tree::Dimension<'a, FragmentSummary> for VersionedFullOffset {
2321 fn add_summary(&mut self, summary: &'a FragmentSummary, cx: &Option<clock::Global>) {
2322 if let Self::Offset(offset) = self {
2323 let version = cx.as_ref().unwrap();
2324 if version.observed_all(&summary.max_insertion_version) {
2325 *offset += summary.text.visible + summary.text.deleted;
2326 } else if version.observed_any(&summary.min_insertion_version) {
2327 *self = Self::Invalid;
2328 }
2329 }
2330 }
2331}
2332
2333impl<'a> sum_tree::SeekTarget<'a, FragmentSummary, Self> for VersionedFullOffset {
2334 fn cmp(&self, cursor_position: &Self, _: &Option<clock::Global>) -> cmp::Ordering {
2335 match (self, cursor_position) {
2336 (Self::Offset(a), Self::Offset(b)) => Ord::cmp(a, b),
2337 (Self::Offset(_), Self::Invalid) => cmp::Ordering::Less,
2338 (Self::Invalid, _) => unreachable!(),
2339 }
2340 }
2341}
2342
2343impl Operation {
2344 fn replica_id(&self) -> ReplicaId {
2345 operation_queue::Operation::lamport_timestamp(self).replica_id
2346 }
2347
2348 pub fn local_timestamp(&self) -> clock::Local {
2349 match self {
2350 Operation::Edit(edit) => edit.timestamp.local(),
2351 Operation::Undo { undo, .. } => undo.id,
2352 }
2353 }
2354
2355 pub fn as_edit(&self) -> Option<&EditOperation> {
2356 match self {
2357 Operation::Edit(edit) => Some(edit),
2358 _ => None,
2359 }
2360 }
2361
2362 pub fn is_edit(&self) -> bool {
2363 matches!(self, Operation::Edit { .. })
2364 }
2365}
2366
2367impl operation_queue::Operation for Operation {
2368 fn lamport_timestamp(&self) -> clock::Lamport {
2369 match self {
2370 Operation::Edit(edit) => edit.timestamp.lamport(),
2371 Operation::Undo {
2372 lamport_timestamp, ..
2373 } => *lamport_timestamp,
2374 }
2375 }
2376}
2377
2378impl Default for LineEnding {
2379 fn default() -> Self {
2380 #[cfg(unix)]
2381 return Self::Unix;
2382
2383 #[cfg(not(unix))]
2384 return Self::CRLF;
2385 }
2386}
2387
2388impl LineEnding {
2389 pub fn as_str(&self) -> &'static str {
2390 match self {
2391 LineEnding::Unix => "\n",
2392 LineEnding::Windows => "\r\n",
2393 }
2394 }
2395
2396 pub fn detect(text: &str) -> Self {
2397 let mut max_ix = cmp::min(text.len(), 1000);
2398 while !text.is_char_boundary(max_ix) {
2399 max_ix -= 1;
2400 }
2401
2402 if let Some(ix) = text[..max_ix].find(&['\n']) {
2403 if ix > 0 && text.as_bytes()[ix - 1] == b'\r' {
2404 Self::Windows
2405 } else {
2406 Self::Unix
2407 }
2408 } else {
2409 Self::default()
2410 }
2411 }
2412
2413 pub fn normalize(text: &mut String) {
2414 if let Cow::Owned(replaced) = CARRIAGE_RETURNS_REGEX.replace_all(text, "\n") {
2415 *text = replaced;
2416 }
2417 }
2418
2419 fn normalize_arc(text: Arc<str>) -> Arc<str> {
2420 if let Cow::Owned(replaced) = CARRIAGE_RETURNS_REGEX.replace_all(&text, "\n") {
2421 replaced.into()
2422 } else {
2423 text
2424 }
2425 }
2426}
2427
2428pub trait ToOffset {
2429 fn to_offset(&self, snapshot: &BufferSnapshot) -> usize;
2430}
2431
2432impl ToOffset for Point {
2433 fn to_offset<'a>(&self, snapshot: &BufferSnapshot) -> usize {
2434 snapshot.point_to_offset(*self)
2435 }
2436}
2437
2438impl ToOffset for PointUtf16 {
2439 fn to_offset<'a>(&self, snapshot: &BufferSnapshot) -> usize {
2440 snapshot.point_utf16_to_offset(*self)
2441 }
2442}
2443
2444impl ToOffset for usize {
2445 fn to_offset<'a>(&self, snapshot: &BufferSnapshot) -> usize {
2446 assert!(*self <= snapshot.len(), "offset is out of range");
2447 *self
2448 }
2449}
2450
2451impl ToOffset for OffsetUtf16 {
2452 fn to_offset<'a>(&self, snapshot: &BufferSnapshot) -> usize {
2453 snapshot.offset_utf16_to_offset(*self)
2454 }
2455}
2456
2457impl ToOffset for Anchor {
2458 fn to_offset<'a>(&self, snapshot: &BufferSnapshot) -> usize {
2459 snapshot.summary_for_anchor(self)
2460 }
2461}
2462
2463impl<'a, T: ToOffset> ToOffset for &'a T {
2464 fn to_offset(&self, content: &BufferSnapshot) -> usize {
2465 (*self).to_offset(content)
2466 }
2467}
2468
2469pub trait ToPoint {
2470 fn to_point(&self, snapshot: &BufferSnapshot) -> Point;
2471}
2472
2473impl ToPoint for Anchor {
2474 fn to_point<'a>(&self, snapshot: &BufferSnapshot) -> Point {
2475 snapshot.summary_for_anchor(self)
2476 }
2477}
2478
2479impl ToPoint for usize {
2480 fn to_point<'a>(&self, snapshot: &BufferSnapshot) -> Point {
2481 snapshot.offset_to_point(*self)
2482 }
2483}
2484
2485impl ToPoint for PointUtf16 {
2486 fn to_point<'a>(&self, snapshot: &BufferSnapshot) -> Point {
2487 snapshot.point_utf16_to_point(*self)
2488 }
2489}
2490
2491impl ToPoint for Point {
2492 fn to_point<'a>(&self, _: &BufferSnapshot) -> Point {
2493 *self
2494 }
2495}
2496
2497pub trait ToPointUtf16 {
2498 fn to_point_utf16(&self, snapshot: &BufferSnapshot) -> PointUtf16;
2499}
2500
2501impl ToPointUtf16 for Anchor {
2502 fn to_point_utf16<'a>(&self, snapshot: &BufferSnapshot) -> PointUtf16 {
2503 snapshot.summary_for_anchor(self)
2504 }
2505}
2506
2507impl ToPointUtf16 for usize {
2508 fn to_point_utf16<'a>(&self, snapshot: &BufferSnapshot) -> PointUtf16 {
2509 snapshot.offset_to_point_utf16(*self)
2510 }
2511}
2512
2513impl ToPointUtf16 for PointUtf16 {
2514 fn to_point_utf16<'a>(&self, _: &BufferSnapshot) -> PointUtf16 {
2515 *self
2516 }
2517}
2518
2519impl ToPointUtf16 for Point {
2520 fn to_point_utf16<'a>(&self, snapshot: &BufferSnapshot) -> PointUtf16 {
2521 snapshot.point_to_point_utf16(*self)
2522 }
2523}
2524
2525pub trait ToOffsetUtf16 {
2526 fn to_offset_utf16(&self, snapshot: &BufferSnapshot) -> OffsetUtf16;
2527}
2528
2529impl ToOffsetUtf16 for Anchor {
2530 fn to_offset_utf16<'a>(&self, snapshot: &BufferSnapshot) -> OffsetUtf16 {
2531 snapshot.summary_for_anchor(self)
2532 }
2533}
2534
2535impl ToOffsetUtf16 for usize {
2536 fn to_offset_utf16<'a>(&self, snapshot: &BufferSnapshot) -> OffsetUtf16 {
2537 snapshot.offset_to_offset_utf16(*self)
2538 }
2539}
2540
2541impl ToOffsetUtf16 for OffsetUtf16 {
2542 fn to_offset_utf16<'a>(&self, _snapshot: &BufferSnapshot) -> OffsetUtf16 {
2543 *self
2544 }
2545}
2546
2547pub trait Clip {
2548 fn clip(&self, bias: Bias, snapshot: &BufferSnapshot) -> Self;
2549}
2550
2551impl Clip for usize {
2552 fn clip(&self, bias: Bias, snapshot: &BufferSnapshot) -> Self {
2553 snapshot.clip_offset(*self, bias)
2554 }
2555}
2556
2557impl Clip for Point {
2558 fn clip(&self, bias: Bias, snapshot: &BufferSnapshot) -> Self {
2559 snapshot.clip_point(*self, bias)
2560 }
2561}
2562
2563impl Clip for PointUtf16 {
2564 fn clip(&self, bias: Bias, snapshot: &BufferSnapshot) -> Self {
2565 snapshot.clip_point_utf16(*self, bias)
2566 }
2567}
2568
2569pub trait FromAnchor {
2570 fn from_anchor(anchor: &Anchor, snapshot: &BufferSnapshot) -> Self;
2571}
2572
2573impl FromAnchor for Point {
2574 fn from_anchor(anchor: &Anchor, snapshot: &BufferSnapshot) -> Self {
2575 snapshot.summary_for_anchor(anchor)
2576 }
2577}
2578
2579impl FromAnchor for PointUtf16 {
2580 fn from_anchor(anchor: &Anchor, snapshot: &BufferSnapshot) -> Self {
2581 snapshot.summary_for_anchor(anchor)
2582 }
2583}
2584
2585impl FromAnchor for usize {
2586 fn from_anchor(anchor: &Anchor, snapshot: &BufferSnapshot) -> Self {
2587 snapshot.summary_for_anchor(anchor)
2588 }
2589}