1use std::{
2 cell::Ref,
3 iter, mem,
4 ops::{Deref, DerefMut, Range, Sub},
5 sync::Arc,
6};
7
8use collections::HashMap;
9use gpui::{AppContext, Model, Pixels};
10use itertools::Itertools;
11use language::{Bias, Point, Selection, SelectionGoal, TextDimension};
12use util::post_inc;
13
14use crate::{
15 display_map::{DisplayMap, DisplaySnapshot, ToDisplayPoint},
16 movement::TextLayoutDetails,
17 Anchor, DisplayPoint, DisplayRow, ExcerptId, MultiBuffer, MultiBufferSnapshot, SelectMode,
18 ToOffset, ToPoint,
19};
20
21#[derive(Debug, Clone)]
22pub struct PendingSelection {
23 pub selection: Selection<Anchor>,
24 pub mode: SelectMode,
25}
26
27#[derive(Debug, Clone)]
28pub struct SelectionsCollection {
29 display_map: Model<DisplayMap>,
30 buffer: Model<MultiBuffer>,
31 pub next_selection_id: usize,
32 pub line_mode: bool,
33 /// The non-pending, non-overlapping selections.
34 /// The [SelectionsCollection::pending] selection could possibly overlap these
35 pub disjoint: Arc<[Selection<Anchor>]>,
36 /// A pending selection, such as when the mouse is being dragged
37 pub pending: Option<PendingSelection>,
38}
39
40impl SelectionsCollection {
41 pub fn new(display_map: Model<DisplayMap>, buffer: Model<MultiBuffer>) -> Self {
42 Self {
43 display_map,
44 buffer,
45 next_selection_id: 1,
46 line_mode: false,
47 disjoint: Arc::default(),
48 pending: Some(PendingSelection {
49 selection: Selection {
50 id: 0,
51 start: Anchor::min(),
52 end: Anchor::min(),
53 reversed: false,
54 goal: SelectionGoal::None,
55 },
56 mode: SelectMode::Character,
57 }),
58 }
59 }
60
61 pub fn display_map(&self, cx: &mut AppContext) -> DisplaySnapshot {
62 self.display_map.update(cx, |map, cx| map.snapshot(cx))
63 }
64
65 fn buffer<'a>(&self, cx: &'a AppContext) -> Ref<'a, MultiBufferSnapshot> {
66 self.buffer.read(cx).read(cx)
67 }
68
69 pub fn clone_state(&mut self, other: &SelectionsCollection) {
70 self.next_selection_id = other.next_selection_id;
71 self.line_mode = other.line_mode;
72 self.disjoint = other.disjoint.clone();
73 self.pending.clone_from(&other.pending);
74 }
75
76 pub fn count(&self) -> usize {
77 let mut count = self.disjoint.len();
78 if self.pending.is_some() {
79 count += 1;
80 }
81 count
82 }
83
84 /// The non-pending, non-overlapping selections. There could still be a pending
85 /// selection that overlaps these if the mouse is being dragged, etc. Returned as
86 /// selections over Anchors.
87 pub fn disjoint_anchors(&self) -> Arc<[Selection<Anchor>]> {
88 self.disjoint.clone()
89 }
90
91 pub fn pending_anchor(&self) -> Option<Selection<Anchor>> {
92 self.pending
93 .as_ref()
94 .map(|pending| pending.selection.clone())
95 }
96
97 pub fn pending<D: TextDimension + Ord + Sub<D, Output = D>>(
98 &self,
99 cx: &mut AppContext,
100 ) -> Option<Selection<D>> {
101 self.pending_anchor()
102 .as_ref()
103 .map(|pending| pending.map(|p| p.summary::<D>(&self.buffer(cx))))
104 }
105
106 pub(crate) fn pending_mode(&self) -> Option<SelectMode> {
107 self.pending.as_ref().map(|pending| pending.mode.clone())
108 }
109
110 pub fn all<'a, D>(&self, cx: &mut AppContext) -> Vec<Selection<D>>
111 where
112 D: 'a + TextDimension + Ord + Sub<D, Output = D>,
113 {
114 let disjoint_anchors = &self.disjoint;
115 let mut disjoint =
116 resolve_multiple::<D, _>(disjoint_anchors.iter(), &self.buffer(cx)).peekable();
117
118 let mut pending_opt = self.pending::<D>(cx);
119
120 iter::from_fn(move || {
121 if let Some(pending) = pending_opt.as_mut() {
122 while let Some(next_selection) = disjoint.peek() {
123 if pending.start <= next_selection.end && pending.end >= next_selection.start {
124 let next_selection = disjoint.next().unwrap();
125 if next_selection.start < pending.start {
126 pending.start = next_selection.start;
127 }
128 if next_selection.end > pending.end {
129 pending.end = next_selection.end;
130 }
131 } else if next_selection.end < pending.start {
132 return disjoint.next();
133 } else {
134 break;
135 }
136 }
137
138 pending_opt.take()
139 } else {
140 disjoint.next()
141 }
142 })
143 .collect()
144 }
145
146 /// Returns all of the selections, adjusted to take into account the selection line_mode
147 pub fn all_adjusted(&self, cx: &mut AppContext) -> Vec<Selection<Point>> {
148 let mut selections = self.all::<Point>(cx);
149 if self.line_mode {
150 let map = self.display_map(cx);
151 for selection in &mut selections {
152 let new_range = map.expand_to_line(selection.range());
153 selection.start = new_range.start;
154 selection.end = new_range.end;
155 }
156 }
157 selections
158 }
159
160 /// Returns the newest selection, adjusted to take into account the selection line_mode
161 pub fn newest_adjusted(&self, cx: &mut AppContext) -> Selection<Point> {
162 let mut selection = self.newest::<Point>(cx);
163 if self.line_mode {
164 let map = self.display_map(cx);
165 let new_range = map.expand_to_line(selection.range());
166 selection.start = new_range.start;
167 selection.end = new_range.end;
168 }
169 selection
170 }
171
172 pub fn all_adjusted_display(
173 &self,
174 cx: &mut AppContext,
175 ) -> (DisplaySnapshot, Vec<Selection<DisplayPoint>>) {
176 if self.line_mode {
177 let selections = self.all::<Point>(cx);
178 let map = self.display_map(cx);
179 let result = selections
180 .into_iter()
181 .map(|mut selection| {
182 let new_range = map.expand_to_line(selection.range());
183 selection.start = new_range.start;
184 selection.end = new_range.end;
185 selection.map(|point| point.to_display_point(&map))
186 })
187 .collect();
188 (map, result)
189 } else {
190 self.all_display(cx)
191 }
192 }
193
194 pub fn disjoint_in_range<'a, D>(
195 &self,
196 range: Range<Anchor>,
197 cx: &mut AppContext,
198 ) -> Vec<Selection<D>>
199 where
200 D: 'a + TextDimension + Ord + Sub<D, Output = D> + std::fmt::Debug,
201 {
202 let buffer = self.buffer(cx);
203 let start_ix = match self
204 .disjoint
205 .binary_search_by(|probe| probe.end.cmp(&range.start, &buffer))
206 {
207 Ok(ix) | Err(ix) => ix,
208 };
209 let end_ix = match self
210 .disjoint
211 .binary_search_by(|probe| probe.start.cmp(&range.end, &buffer))
212 {
213 Ok(ix) => ix + 1,
214 Err(ix) => ix,
215 };
216 resolve_multiple(&self.disjoint[start_ix..end_ix], &buffer).collect()
217 }
218
219 pub fn all_display(
220 &self,
221 cx: &mut AppContext,
222 ) -> (DisplaySnapshot, Vec<Selection<DisplayPoint>>) {
223 let display_map = self.display_map(cx);
224 let selections = self
225 .all::<Point>(cx)
226 .into_iter()
227 .map(|selection| selection.map(|point| point.to_display_point(&display_map)))
228 .collect();
229 (display_map, selections)
230 }
231
232 pub fn newest_anchor(&self) -> &Selection<Anchor> {
233 self.pending
234 .as_ref()
235 .map(|s| &s.selection)
236 .or_else(|| self.disjoint.iter().max_by_key(|s| s.id))
237 .unwrap()
238 }
239
240 pub fn newest<D: TextDimension + Ord + Sub<D, Output = D>>(
241 &self,
242 cx: &mut AppContext,
243 ) -> Selection<D> {
244 let buffer = self.buffer(cx);
245 self.newest_anchor().map(|p| p.summary::<D>(&buffer))
246 }
247
248 pub fn newest_display(&self, cx: &mut AppContext) -> Selection<DisplayPoint> {
249 let display_map = self.display_map(cx);
250 let selection = self
251 .newest_anchor()
252 .map(|point| point.to_display_point(&display_map));
253 selection
254 }
255
256 pub fn oldest_anchor(&self) -> &Selection<Anchor> {
257 self.disjoint
258 .iter()
259 .min_by_key(|s| s.id)
260 .or_else(|| self.pending.as_ref().map(|p| &p.selection))
261 .unwrap()
262 }
263
264 pub fn oldest<D: TextDimension + Ord + Sub<D, Output = D>>(
265 &self,
266 cx: &mut AppContext,
267 ) -> Selection<D> {
268 let buffer = self.buffer(cx);
269 self.oldest_anchor().map(|p| p.summary::<D>(&buffer))
270 }
271
272 pub fn first_anchor(&self) -> Selection<Anchor> {
273 self.pending
274 .as_ref()
275 .map(|pending| pending.selection.clone())
276 .unwrap_or_else(|| self.disjoint.first().cloned().unwrap())
277 }
278
279 pub fn first<D: TextDimension + Ord + Sub<D, Output = D>>(
280 &self,
281 cx: &mut AppContext,
282 ) -> Selection<D> {
283 self.all(cx).first().unwrap().clone()
284 }
285
286 pub fn last<D: TextDimension + Ord + Sub<D, Output = D>>(
287 &self,
288 cx: &mut AppContext,
289 ) -> Selection<D> {
290 self.all(cx).last().unwrap().clone()
291 }
292
293 pub fn disjoint_anchor_ranges(&self) -> Vec<Range<Anchor>> {
294 self.disjoint_anchors()
295 .iter()
296 .map(|s| s.start..s.end)
297 .collect()
298 }
299
300 #[cfg(any(test, feature = "test-support"))]
301 pub fn ranges<D: TextDimension + Ord + Sub<D, Output = D> + std::fmt::Debug>(
302 &self,
303 cx: &mut AppContext,
304 ) -> Vec<Range<D>> {
305 self.all::<D>(cx)
306 .iter()
307 .map(|s| {
308 if s.reversed {
309 s.end.clone()..s.start.clone()
310 } else {
311 s.start.clone()..s.end.clone()
312 }
313 })
314 .collect()
315 }
316
317 #[cfg(any(test, feature = "test-support"))]
318 pub fn display_ranges(&self, cx: &mut AppContext) -> Vec<Range<DisplayPoint>> {
319 let display_map = self.display_map(cx);
320 self.disjoint_anchors()
321 .iter()
322 .chain(self.pending_anchor().as_ref())
323 .map(|s| {
324 if s.reversed {
325 s.end.to_display_point(&display_map)..s.start.to_display_point(&display_map)
326 } else {
327 s.start.to_display_point(&display_map)..s.end.to_display_point(&display_map)
328 }
329 })
330 .collect()
331 }
332
333 pub fn build_columnar_selection(
334 &mut self,
335 display_map: &DisplaySnapshot,
336 row: DisplayRow,
337 positions: &Range<Pixels>,
338 reversed: bool,
339 text_layout_details: &TextLayoutDetails,
340 ) -> Option<Selection<Point>> {
341 let is_empty = positions.start == positions.end;
342 let line_len = display_map.line_len(row);
343
344 let line = display_map.layout_row(row, text_layout_details);
345
346 let start_col = line.closest_index_for_x(positions.start) as u32;
347 if start_col < line_len || (is_empty && positions.start == line.width) {
348 let start = DisplayPoint::new(row, start_col);
349 let end_col = line.closest_index_for_x(positions.end) as u32;
350 let end = DisplayPoint::new(row, end_col);
351
352 Some(Selection {
353 id: post_inc(&mut self.next_selection_id),
354 start: start.to_point(display_map),
355 end: end.to_point(display_map),
356 reversed,
357 goal: SelectionGoal::HorizontalRange {
358 start: positions.start.into(),
359 end: positions.end.into(),
360 },
361 })
362 } else {
363 None
364 }
365 }
366
367 pub(crate) fn change_with<R>(
368 &mut self,
369 cx: &mut AppContext,
370 change: impl FnOnce(&mut MutableSelectionsCollection) -> R,
371 ) -> (bool, R) {
372 let mut mutable_collection = MutableSelectionsCollection {
373 collection: self,
374 selections_changed: false,
375 cx,
376 };
377
378 let result = change(&mut mutable_collection);
379 assert!(
380 !mutable_collection.disjoint.is_empty() || mutable_collection.pending.is_some(),
381 "There must be at least one selection"
382 );
383 (mutable_collection.selections_changed, result)
384 }
385}
386
387pub struct MutableSelectionsCollection<'a> {
388 collection: &'a mut SelectionsCollection,
389 selections_changed: bool,
390 cx: &'a mut AppContext,
391}
392
393impl<'a> MutableSelectionsCollection<'a> {
394 pub fn display_map(&mut self) -> DisplaySnapshot {
395 self.collection.display_map(self.cx)
396 }
397
398 pub fn buffer(&self) -> Ref<MultiBufferSnapshot> {
399 self.collection.buffer(self.cx)
400 }
401
402 pub fn clear_disjoint(&mut self) {
403 self.collection.disjoint = Arc::default();
404 }
405
406 pub fn delete(&mut self, selection_id: usize) {
407 let mut changed = false;
408 self.collection.disjoint = self
409 .disjoint
410 .iter()
411 .filter(|selection| {
412 let found = selection.id == selection_id;
413 changed |= found;
414 !found
415 })
416 .cloned()
417 .collect();
418
419 self.selections_changed |= changed;
420 }
421
422 pub fn clear_pending(&mut self) {
423 if self.collection.pending.is_some() {
424 self.collection.pending = None;
425 self.selections_changed = true;
426 }
427 }
428
429 pub(crate) fn set_pending_anchor_range(&mut self, range: Range<Anchor>, mode: SelectMode) {
430 self.collection.pending = Some(PendingSelection {
431 selection: Selection {
432 id: post_inc(&mut self.collection.next_selection_id),
433 start: range.start,
434 end: range.end,
435 reversed: false,
436 goal: SelectionGoal::None,
437 },
438 mode,
439 });
440 self.selections_changed = true;
441 }
442
443 pub(crate) fn set_pending(&mut self, selection: Selection<Anchor>, mode: SelectMode) {
444 self.collection.pending = Some(PendingSelection { selection, mode });
445 self.selections_changed = true;
446 }
447
448 pub fn try_cancel(&mut self) -> bool {
449 if let Some(pending) = self.collection.pending.take() {
450 if self.disjoint.is_empty() {
451 self.collection.disjoint = Arc::from([pending.selection]);
452 }
453 self.selections_changed = true;
454 return true;
455 }
456
457 let mut oldest = self.oldest_anchor().clone();
458 if self.count() > 1 {
459 self.collection.disjoint = Arc::from([oldest]);
460 self.selections_changed = true;
461 return true;
462 }
463
464 if !oldest.start.cmp(&oldest.end, &self.buffer()).is_eq() {
465 let head = oldest.head();
466 oldest.start = head;
467 oldest.end = head;
468 self.collection.disjoint = Arc::from([oldest]);
469 self.selections_changed = true;
470 return true;
471 }
472
473 false
474 }
475
476 pub fn insert_range<T>(&mut self, range: Range<T>)
477 where
478 T: 'a + ToOffset + ToPoint + TextDimension + Ord + Sub<T, Output = T> + std::marker::Copy,
479 {
480 let mut selections = self.collection.all(self.cx);
481 let mut start = range.start.to_offset(&self.buffer());
482 let mut end = range.end.to_offset(&self.buffer());
483 let reversed = if start > end {
484 mem::swap(&mut start, &mut end);
485 true
486 } else {
487 false
488 };
489 selections.push(Selection {
490 id: post_inc(&mut self.collection.next_selection_id),
491 start,
492 end,
493 reversed,
494 goal: SelectionGoal::None,
495 });
496 self.select(selections);
497 }
498
499 pub fn select<T>(&mut self, mut selections: Vec<Selection<T>>)
500 where
501 T: ToOffset + ToPoint + Ord + std::marker::Copy + std::fmt::Debug,
502 {
503 let buffer = self.buffer.read(self.cx).snapshot(self.cx);
504 selections.sort_unstable_by_key(|s| s.start);
505 // Merge overlapping selections.
506 let mut i = 1;
507 while i < selections.len() {
508 if selections[i - 1].end >= selections[i].start {
509 let removed = selections.remove(i);
510 if removed.start < selections[i - 1].start {
511 selections[i - 1].start = removed.start;
512 }
513 if removed.end > selections[i - 1].end {
514 selections[i - 1].end = removed.end;
515 }
516 } else {
517 i += 1;
518 }
519 }
520
521 self.collection.disjoint = Arc::from_iter(selections.into_iter().map(|selection| {
522 let end_bias = if selection.end > selection.start {
523 Bias::Left
524 } else {
525 Bias::Right
526 };
527 Selection {
528 id: selection.id,
529 start: buffer.anchor_after(selection.start),
530 end: buffer.anchor_at(selection.end, end_bias),
531 reversed: selection.reversed,
532 goal: selection.goal,
533 }
534 }));
535
536 self.collection.pending = None;
537 self.selections_changed = true;
538 }
539
540 pub fn select_anchors(&mut self, selections: Vec<Selection<Anchor>>) {
541 let buffer = self.buffer.read(self.cx).snapshot(self.cx);
542 let resolved_selections =
543 resolve_multiple::<usize, _>(&selections, &buffer).collect::<Vec<_>>();
544 self.select(resolved_selections);
545 }
546
547 pub fn select_ranges<I, T>(&mut self, ranges: I)
548 where
549 I: IntoIterator<Item = Range<T>>,
550 T: ToOffset,
551 {
552 let buffer = self.buffer.read(self.cx).snapshot(self.cx);
553 let ranges = ranges
554 .into_iter()
555 .map(|range| range.start.to_offset(&buffer)..range.end.to_offset(&buffer));
556 self.select_offset_ranges(ranges);
557 }
558
559 fn select_offset_ranges<I>(&mut self, ranges: I)
560 where
561 I: IntoIterator<Item = Range<usize>>,
562 {
563 let selections = ranges
564 .into_iter()
565 .map(|range| {
566 let mut start = range.start;
567 let mut end = range.end;
568 let reversed = if start > end {
569 mem::swap(&mut start, &mut end);
570 true
571 } else {
572 false
573 };
574 Selection {
575 id: post_inc(&mut self.collection.next_selection_id),
576 start,
577 end,
578 reversed,
579 goal: SelectionGoal::None,
580 }
581 })
582 .collect::<Vec<_>>();
583
584 self.select(selections)
585 }
586
587 pub fn select_anchor_ranges<I>(&mut self, ranges: I)
588 where
589 I: IntoIterator<Item = Range<Anchor>>,
590 {
591 let buffer = self.buffer.read(self.cx).snapshot(self.cx);
592 let selections = ranges
593 .into_iter()
594 .map(|range| {
595 let mut start = range.start;
596 let mut end = range.end;
597 let reversed = if start.cmp(&end, &buffer).is_gt() {
598 mem::swap(&mut start, &mut end);
599 true
600 } else {
601 false
602 };
603 Selection {
604 id: post_inc(&mut self.collection.next_selection_id),
605 start,
606 end,
607 reversed,
608 goal: SelectionGoal::None,
609 }
610 })
611 .collect::<Vec<_>>();
612 self.select_anchors(selections)
613 }
614
615 pub fn new_selection_id(&mut self) -> usize {
616 post_inc(&mut self.next_selection_id)
617 }
618
619 pub fn select_display_ranges<T>(&mut self, ranges: T)
620 where
621 T: IntoIterator<Item = Range<DisplayPoint>>,
622 {
623 let display_map = self.display_map();
624 let selections = ranges
625 .into_iter()
626 .map(|range| {
627 let mut start = range.start;
628 let mut end = range.end;
629 let reversed = if start > end {
630 mem::swap(&mut start, &mut end);
631 true
632 } else {
633 false
634 };
635 Selection {
636 id: post_inc(&mut self.collection.next_selection_id),
637 start: start.to_point(&display_map),
638 end: end.to_point(&display_map),
639 reversed,
640 goal: SelectionGoal::None,
641 }
642 })
643 .collect();
644 self.select(selections);
645 }
646
647 pub fn move_with(
648 &mut self,
649 mut move_selection: impl FnMut(&DisplaySnapshot, &mut Selection<DisplayPoint>),
650 ) {
651 let mut changed = false;
652 let display_map = self.display_map();
653 let selections = self
654 .collection
655 .all::<Point>(self.cx)
656 .into_iter()
657 .map(|selection| {
658 let mut moved_selection =
659 selection.map(|point| point.to_display_point(&display_map));
660 move_selection(&display_map, &mut moved_selection);
661 let moved_selection =
662 moved_selection.map(|display_point| display_point.to_point(&display_map));
663 if selection != moved_selection {
664 changed = true;
665 }
666 moved_selection
667 })
668 .collect();
669
670 if changed {
671 self.select(selections)
672 }
673 }
674
675 pub fn move_offsets_with(
676 &mut self,
677 mut move_selection: impl FnMut(&MultiBufferSnapshot, &mut Selection<usize>),
678 ) {
679 let mut changed = false;
680 let snapshot = self.buffer().clone();
681 let selections = self
682 .collection
683 .all::<usize>(self.cx)
684 .into_iter()
685 .map(|selection| {
686 let mut moved_selection = selection.clone();
687 move_selection(&snapshot, &mut moved_selection);
688 if selection != moved_selection {
689 changed = true;
690 }
691 moved_selection
692 })
693 .collect();
694 drop(snapshot);
695
696 if changed {
697 self.select(selections)
698 }
699 }
700
701 pub fn move_heads_with(
702 &mut self,
703 mut update_head: impl FnMut(
704 &DisplaySnapshot,
705 DisplayPoint,
706 SelectionGoal,
707 ) -> (DisplayPoint, SelectionGoal),
708 ) {
709 self.move_with(|map, selection| {
710 let (new_head, new_goal) = update_head(map, selection.head(), selection.goal);
711 selection.set_head(new_head, new_goal);
712 });
713 }
714
715 pub fn move_cursors_with(
716 &mut self,
717 mut update_cursor_position: impl FnMut(
718 &DisplaySnapshot,
719 DisplayPoint,
720 SelectionGoal,
721 ) -> (DisplayPoint, SelectionGoal),
722 ) {
723 self.move_with(|map, selection| {
724 let (cursor, new_goal) = update_cursor_position(map, selection.head(), selection.goal);
725 selection.collapse_to(cursor, new_goal)
726 });
727 }
728
729 pub fn maybe_move_cursors_with(
730 &mut self,
731 mut update_cursor_position: impl FnMut(
732 &DisplaySnapshot,
733 DisplayPoint,
734 SelectionGoal,
735 ) -> Option<(DisplayPoint, SelectionGoal)>,
736 ) {
737 self.move_cursors_with(|map, point, goal| {
738 update_cursor_position(map, point, goal).unwrap_or((point, goal))
739 })
740 }
741
742 pub fn replace_cursors_with(
743 &mut self,
744 mut find_replacement_cursors: impl FnMut(&DisplaySnapshot) -> Vec<DisplayPoint>,
745 ) {
746 let display_map = self.display_map();
747 let new_selections = find_replacement_cursors(&display_map)
748 .into_iter()
749 .map(|cursor| {
750 let cursor_point = cursor.to_point(&display_map);
751 Selection {
752 id: post_inc(&mut self.collection.next_selection_id),
753 start: cursor_point,
754 end: cursor_point,
755 reversed: false,
756 goal: SelectionGoal::None,
757 }
758 })
759 .collect();
760 self.select(new_selections);
761 }
762
763 /// Compute new ranges for any selections that were located in excerpts that have
764 /// since been removed.
765 ///
766 /// Returns a `HashMap` indicating which selections whose former head position
767 /// was no longer present. The keys of the map are selection ids. The values are
768 /// the id of the new excerpt where the head of the selection has been moved.
769 pub fn refresh(&mut self) -> HashMap<usize, ExcerptId> {
770 let mut pending = self.collection.pending.take();
771 let mut selections_with_lost_position = HashMap::default();
772
773 let anchors_with_status = {
774 let buffer = self.buffer();
775 let disjoint_anchors = self
776 .disjoint
777 .iter()
778 .flat_map(|selection| [&selection.start, &selection.end]);
779 buffer.refresh_anchors(disjoint_anchors)
780 };
781 let adjusted_disjoint: Vec<_> = anchors_with_status
782 .chunks(2)
783 .map(|selection_anchors| {
784 let (anchor_ix, start, kept_start) = selection_anchors[0];
785 let (_, end, kept_end) = selection_anchors[1];
786 let selection = &self.disjoint[anchor_ix / 2];
787 let kept_head = if selection.reversed {
788 kept_start
789 } else {
790 kept_end
791 };
792 if !kept_head {
793 selections_with_lost_position.insert(selection.id, selection.head().excerpt_id);
794 }
795
796 Selection {
797 id: selection.id,
798 start,
799 end,
800 reversed: selection.reversed,
801 goal: selection.goal,
802 }
803 })
804 .collect();
805
806 if !adjusted_disjoint.is_empty() {
807 let resolved_selections =
808 resolve_multiple(adjusted_disjoint.iter(), &self.buffer()).collect();
809 self.select::<usize>(resolved_selections);
810 }
811
812 if let Some(pending) = pending.as_mut() {
813 let buffer = self.buffer();
814 let anchors =
815 buffer.refresh_anchors([&pending.selection.start, &pending.selection.end]);
816 let (_, start, kept_start) = anchors[0];
817 let (_, end, kept_end) = anchors[1];
818 let kept_head = if pending.selection.reversed {
819 kept_start
820 } else {
821 kept_end
822 };
823 if !kept_head {
824 selections_with_lost_position
825 .insert(pending.selection.id, pending.selection.head().excerpt_id);
826 }
827
828 pending.selection.start = start;
829 pending.selection.end = end;
830 }
831 self.collection.pending = pending;
832 self.selections_changed = true;
833
834 selections_with_lost_position
835 }
836}
837
838impl<'a> Deref for MutableSelectionsCollection<'a> {
839 type Target = SelectionsCollection;
840 fn deref(&self) -> &Self::Target {
841 self.collection
842 }
843}
844
845impl<'a> DerefMut for MutableSelectionsCollection<'a> {
846 fn deref_mut(&mut self) -> &mut Self::Target {
847 self.collection
848 }
849}
850
851// Panics if passed selections are not in order
852pub(crate) fn resolve_multiple<'a, D, I>(
853 selections: I,
854 snapshot: &MultiBufferSnapshot,
855) -> impl 'a + Iterator<Item = Selection<D>>
856where
857 D: TextDimension + Ord + Sub<D, Output = D>,
858 I: 'a + IntoIterator<Item = &'a Selection<Anchor>>,
859{
860 let (to_summarize, selections) = selections.into_iter().tee();
861 let mut summaries = snapshot
862 .summaries_for_anchors::<D, _>(
863 to_summarize
864 .flat_map(|s| [&s.start, &s.end])
865 .collect::<Vec<_>>(),
866 )
867 .into_iter();
868 selections.map(move |s| Selection {
869 id: s.id,
870 start: summaries.next().unwrap(),
871 end: summaries.next().unwrap(),
872 reversed: s.reversed,
873 goal: s.goal,
874 })
875}