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