1use futures::channel::oneshot;
2use git2::{DiffLineType as GitDiffLineType, DiffOptions as GitOptions, Patch as GitPatch};
3use gpui::{App, AppContext as _, Context, Entity, EventEmitter, Task};
4use language::{
5 Capability, Diff, DiffOptions, File, Language, LanguageName, LanguageRegistry,
6 language_settings::language_settings, word_diff_ranges,
7};
8use rope::Rope;
9use std::{
10 cmp::Ordering,
11 future::Future,
12 iter,
13 ops::{Range, RangeInclusive},
14 sync::Arc,
15};
16use sum_tree::SumTree;
17use text::{
18 Anchor, Bias, BufferId, Edit, OffsetRangeExt, Patch, Point, ToOffset as _, ToPoint as _,
19};
20use util::ResultExt;
21
22pub const MAX_WORD_DIFF_LINE_COUNT: usize = 5;
23
24pub struct BufferDiff {
25 pub buffer_id: BufferId,
26 inner: BufferDiffInner<Entity<language::Buffer>>,
27 secondary_diff: Option<Entity<BufferDiff>>,
28}
29
30#[derive(Clone)]
31pub struct BufferDiffSnapshot {
32 inner: BufferDiffInner<language::BufferSnapshot>,
33 secondary_diff: Option<Arc<BufferDiffSnapshot>>,
34}
35
36impl std::fmt::Debug for BufferDiffSnapshot {
37 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
38 f.debug_struct("BufferDiffSnapshot")
39 .field("inner", &self.inner)
40 .field("secondary_diff", &self.secondary_diff)
41 .finish()
42 }
43}
44
45#[derive(Clone)]
46pub struct BufferDiffUpdate {
47 inner: BufferDiffInner<Arc<str>>,
48 buffer_snapshot: text::BufferSnapshot,
49 base_text_edits: Option<Diff>,
50 base_text_changed: bool,
51}
52
53impl BufferDiffUpdate {
54 pub fn from_hunks(
55 base_text: Arc<str>,
56 base_snapshot: &Rope,
57 buffer_snapshot: text::BufferSnapshot,
58 edits: Patch<usize>,
59 diff_options: Option<DiffOptions>,
60 ) -> Self {
61 let hunks = edits.into_iter().map(|edit| {
62 let buffer_range = buffer_snapshot.anchor_after(edit.new.start)
63 ..buffer_snapshot.anchor_after(edit.new.end);
64
65 let (base_word_diffs, buffer_word_diffs) = if let Some(options) = &diff_options {
66 word_diffs(
67 base_snapshot,
68 edit.old.clone(),
69 &buffer_snapshot,
70 buffer_range,
71 options,
72 )
73 } else {
74 (Vec::new(), Vec::new())
75 };
76 InternalDiffHunk {
77 buffer_range: buffer_snapshot.anchor_before(edit.new.start)
78 ..buffer_snapshot.anchor_before(edit.new.end),
79 diff_base_byte_range: edit.old,
80 base_word_diffs,
81 buffer_word_diffs,
82 }
83 });
84
85 Self {
86 inner: BufferDiffInner {
87 hunks: SumTree::from_iter(hunks, &buffer_snapshot),
88 pending_hunks: SumTree::new(&buffer_snapshot),
89 base_text,
90 base_text_exists: true,
91 buffer_snapshot: buffer_snapshot.clone(),
92 },
93 buffer_snapshot,
94 base_text_edits: None,
95 base_text_changed: false,
96 }
97 }
98}
99
100#[derive(Clone)]
101struct BufferDiffInner<BaseText> {
102 hunks: SumTree<InternalDiffHunk>,
103 pending_hunks: SumTree<PendingHunk>,
104 base_text: BaseText,
105 base_text_exists: bool,
106 buffer_snapshot: text::BufferSnapshot,
107}
108
109impl<BaseText> BufferDiffInner<BaseText> {
110 fn buffer_version(&self) -> &clock::Global {
111 self.buffer_snapshot.version()
112 }
113}
114
115#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
116pub struct DiffHunkStatus {
117 pub kind: DiffHunkStatusKind,
118 pub secondary: DiffHunkSecondaryStatus,
119}
120
121#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
122pub enum DiffHunkStatusKind {
123 Added,
124 Modified,
125 Deleted,
126}
127
128#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
129/// Diff of Working Copy vs Index
130/// aka 'is this hunk staged or not'
131pub enum DiffHunkSecondaryStatus {
132 /// Unstaged
133 HasSecondaryHunk,
134 /// Partially staged
135 OverlapsWithSecondaryHunk,
136 /// Staged
137 NoSecondaryHunk,
138 /// We are unstaging
139 SecondaryHunkAdditionPending,
140 /// We are stagind
141 SecondaryHunkRemovalPending,
142}
143
144/// A diff hunk resolved to rows in the buffer.
145#[derive(Debug, Clone, PartialEq, Eq)]
146pub struct DiffHunk {
147 /// The buffer range as points.
148 pub range: Range<Point>,
149 /// The range in the buffer to which this hunk corresponds.
150 pub buffer_range: Range<Anchor>,
151 /// The range in the buffer's diff base text to which this hunk corresponds.
152 pub diff_base_byte_range: Range<usize>,
153 pub secondary_status: DiffHunkSecondaryStatus,
154 // Anchors representing the word diff locations in the active buffer
155 pub buffer_word_diffs: Vec<Range<Anchor>>,
156 // Offsets relative to the start of the deleted diff that represent word diff locations
157 pub base_word_diffs: Vec<Range<usize>>,
158}
159
160/// We store [`InternalDiffHunk`]s internally so we don't need to store the additional row range.
161#[derive(Debug, Clone, PartialEq, Eq)]
162struct InternalDiffHunk {
163 buffer_range: Range<Anchor>,
164 diff_base_byte_range: Range<usize>,
165 base_word_diffs: Vec<Range<usize>>,
166 buffer_word_diffs: Vec<Range<Anchor>>,
167}
168
169#[derive(Debug, Clone, PartialEq, Eq)]
170struct PendingHunk {
171 buffer_range: Range<Anchor>,
172 diff_base_byte_range: Range<usize>,
173 buffer_version: clock::Global,
174 new_status: DiffHunkSecondaryStatus,
175}
176
177#[derive(Debug, Clone)]
178pub struct DiffHunkSummary {
179 buffer_range: Range<Anchor>,
180 diff_base_byte_range: Range<usize>,
181}
182
183impl sum_tree::Item for InternalDiffHunk {
184 type Summary = DiffHunkSummary;
185
186 fn summary(&self, _cx: &text::BufferSnapshot) -> Self::Summary {
187 DiffHunkSummary {
188 buffer_range: self.buffer_range.clone(),
189 diff_base_byte_range: self.diff_base_byte_range.clone(),
190 }
191 }
192}
193
194impl sum_tree::Item for PendingHunk {
195 type Summary = DiffHunkSummary;
196
197 fn summary(&self, _cx: &text::BufferSnapshot) -> Self::Summary {
198 DiffHunkSummary {
199 buffer_range: self.buffer_range.clone(),
200 diff_base_byte_range: self.diff_base_byte_range.clone(),
201 }
202 }
203}
204
205impl sum_tree::Summary for DiffHunkSummary {
206 type Context<'a> = &'a text::BufferSnapshot;
207
208 fn zero(_cx: Self::Context<'_>) -> Self {
209 DiffHunkSummary {
210 buffer_range: Anchor::MIN..Anchor::MIN,
211 diff_base_byte_range: 0..0,
212 }
213 }
214
215 fn add_summary(&mut self, other: &Self, buffer: Self::Context<'_>) {
216 self.buffer_range.start = *self
217 .buffer_range
218 .start
219 .min(&other.buffer_range.start, buffer);
220 self.buffer_range.end = *self.buffer_range.end.max(&other.buffer_range.end, buffer);
221
222 self.diff_base_byte_range.start = self
223 .diff_base_byte_range
224 .start
225 .min(other.diff_base_byte_range.start);
226 self.diff_base_byte_range.end = self
227 .diff_base_byte_range
228 .end
229 .max(other.diff_base_byte_range.end);
230 }
231}
232
233impl sum_tree::SeekTarget<'_, DiffHunkSummary, DiffHunkSummary> for Anchor {
234 fn cmp(&self, cursor_location: &DiffHunkSummary, buffer: &text::BufferSnapshot) -> Ordering {
235 if self
236 .cmp(&cursor_location.buffer_range.start, buffer)
237 .is_lt()
238 {
239 Ordering::Less
240 } else if self.cmp(&cursor_location.buffer_range.end, buffer).is_gt() {
241 Ordering::Greater
242 } else {
243 Ordering::Equal
244 }
245 }
246}
247
248impl sum_tree::SeekTarget<'_, DiffHunkSummary, DiffHunkSummary> for usize {
249 fn cmp(&self, cursor_location: &DiffHunkSummary, _cx: &text::BufferSnapshot) -> Ordering {
250 if *self < cursor_location.diff_base_byte_range.start {
251 Ordering::Less
252 } else if *self > cursor_location.diff_base_byte_range.end {
253 Ordering::Greater
254 } else {
255 Ordering::Equal
256 }
257 }
258}
259
260impl std::fmt::Debug for BufferDiffInner<language::BufferSnapshot> {
261 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
262 f.debug_struct("BufferDiffSnapshot")
263 .field("hunks", &self.hunks)
264 .field("remote_id", &self.base_text.remote_id())
265 .finish()
266 }
267}
268
269impl BufferDiffSnapshot {
270 #[cfg(test)]
271 fn new_sync(
272 buffer: &text::BufferSnapshot,
273 diff_base: String,
274 cx: &mut gpui::TestAppContext,
275 ) -> BufferDiffSnapshot {
276 let buffer_diff = cx.new(|cx| BufferDiff::new_with_base_text(&diff_base, buffer, cx));
277 buffer_diff.update(cx, |buffer_diff, cx| buffer_diff.snapshot(cx))
278 }
279
280 pub fn is_empty(&self) -> bool {
281 self.inner.hunks.is_empty()
282 }
283
284 pub fn base_text_string(&self) -> Option<String> {
285 self.inner
286 .base_text_exists
287 .then(|| self.inner.base_text.text())
288 }
289
290 pub fn secondary_diff(&self) -> Option<&BufferDiffSnapshot> {
291 self.secondary_diff.as_deref()
292 }
293
294 pub fn buffer_version(&self) -> &clock::Global {
295 self.inner.buffer_version()
296 }
297
298 fn original_buffer_snapshot(&self) -> &text::BufferSnapshot {
299 &self.inner.buffer_snapshot
300 }
301
302 #[ztracing::instrument(skip_all)]
303 pub fn hunks_intersecting_range<'a>(
304 &'a self,
305 range: Range<Anchor>,
306 buffer: &'a text::BufferSnapshot,
307 ) -> impl 'a + Iterator<Item = DiffHunk> {
308 let unstaged_counterpart = self.secondary_diff.as_ref().map(|diff| &diff.inner);
309 self.inner
310 .hunks_intersecting_range(range, buffer, unstaged_counterpart)
311 }
312
313 pub fn hunks_intersecting_range_rev<'a>(
314 &'a self,
315 range: Range<Anchor>,
316 buffer: &'a text::BufferSnapshot,
317 ) -> impl 'a + Iterator<Item = DiffHunk> {
318 let filter = move |summary: &DiffHunkSummary| {
319 let before_start = summary.buffer_range.end.cmp(&range.start, buffer).is_lt();
320 let after_end = summary.buffer_range.start.cmp(&range.end, buffer).is_gt();
321 !before_start && !after_end
322 };
323 self.inner.hunks_intersecting_range_rev_impl(filter, buffer)
324 }
325
326 pub fn hunks_intersecting_base_text_range<'a>(
327 &'a self,
328 range: Range<usize>,
329 main_buffer: &'a text::BufferSnapshot,
330 ) -> impl 'a + Iterator<Item = DiffHunk> {
331 let unstaged_counterpart = self.secondary_diff.as_ref().map(|diff| &diff.inner);
332 let filter = move |summary: &DiffHunkSummary| {
333 let before_start = summary.diff_base_byte_range.end < range.start;
334 let after_end = summary.diff_base_byte_range.start > range.end;
335 !before_start && !after_end
336 };
337 self.inner
338 .hunks_intersecting_range_impl(filter, main_buffer, unstaged_counterpart)
339 }
340
341 pub fn hunks_intersecting_base_text_range_rev<'a>(
342 &'a self,
343 range: Range<usize>,
344 main_buffer: &'a text::BufferSnapshot,
345 ) -> impl 'a + Iterator<Item = DiffHunk> {
346 let filter = move |summary: &DiffHunkSummary| {
347 let before_start = summary.diff_base_byte_range.end.cmp(&range.start).is_lt();
348 let after_end = summary.diff_base_byte_range.start.cmp(&range.end).is_gt();
349 !before_start && !after_end
350 };
351 self.inner
352 .hunks_intersecting_range_rev_impl(filter, main_buffer)
353 }
354
355 pub fn hunks<'a>(
356 &'a self,
357 buffer_snapshot: &'a text::BufferSnapshot,
358 ) -> impl 'a + Iterator<Item = DiffHunk> {
359 self.hunks_intersecting_range(
360 Anchor::min_max_range_for_buffer(buffer_snapshot.remote_id()),
361 buffer_snapshot,
362 )
363 }
364
365 pub fn hunks_in_row_range<'a>(
366 &'a self,
367 range: Range<u32>,
368 buffer: &'a text::BufferSnapshot,
369 ) -> impl 'a + Iterator<Item = DiffHunk> {
370 let start = buffer.anchor_before(Point::new(range.start, 0));
371 let end = buffer.anchor_after(Point::new(range.end, 0));
372 self.hunks_intersecting_range(start..end, buffer)
373 }
374
375 pub fn range_to_hunk_range(
376 &self,
377 range: Range<Anchor>,
378 buffer: &text::BufferSnapshot,
379 ) -> (Option<Range<Anchor>>, Option<Range<usize>>) {
380 let first_hunk = self.hunks_intersecting_range(range.clone(), buffer).next();
381 let last_hunk = self.hunks_intersecting_range_rev(range, buffer).next();
382 let range = first_hunk
383 .as_ref()
384 .zip(last_hunk.as_ref())
385 .map(|(first, last)| first.buffer_range.start..last.buffer_range.end);
386 let base_text_range = first_hunk
387 .zip(last_hunk)
388 .map(|(first, last)| first.diff_base_byte_range.start..last.diff_base_byte_range.end);
389 (range, base_text_range)
390 }
391
392 pub fn base_text(&self) -> &language::BufferSnapshot {
393 &self.inner.base_text
394 }
395
396 /// If this function returns `true`, the base texts are equal. If this
397 /// function returns `false`, they might be equal, but might not. This
398 /// result is used to avoid recalculating diffs in situations where we know
399 /// nothing has changed.
400 pub fn base_texts_definitely_eq(&self, other: &Self) -> bool {
401 if self.inner.base_text_exists != other.inner.base_text_exists {
402 return false;
403 }
404 let left = &self.inner.base_text;
405 let right = &other.inner.base_text;
406 let (old_id, old_version, old_empty) = (left.remote_id(), left.version(), left.is_empty());
407 let (new_id, new_version, new_empty) =
408 (right.remote_id(), right.version(), right.is_empty());
409 (new_id == old_id && new_version == old_version) || (new_empty && old_empty)
410 }
411
412 /// Returns the last hunk whose start is less than or equal to the given position.
413 fn hunk_before_base_text_offset<'a>(
414 &self,
415 target: usize,
416 cursor: &mut sum_tree::Cursor<'a, '_, InternalDiffHunk, DiffHunkSummary>,
417 ) -> Option<&'a InternalDiffHunk> {
418 cursor.seek_forward(&target, Bias::Left);
419 if cursor
420 .item()
421 .is_none_or(|hunk| target < hunk.diff_base_byte_range.start)
422 {
423 cursor.prev();
424 }
425 cursor
426 .item()
427 .filter(|hunk| target >= hunk.diff_base_byte_range.start)
428 }
429
430 fn hunk_before_buffer_anchor<'a>(
431 &self,
432 target: Anchor,
433 cursor: &mut sum_tree::Cursor<'a, '_, InternalDiffHunk, DiffHunkSummary>,
434 buffer: &text::BufferSnapshot,
435 ) -> Option<&'a InternalDiffHunk> {
436 cursor.seek_forward(&target, Bias::Left);
437 if cursor
438 .item()
439 .is_none_or(|hunk| target.cmp(&hunk.buffer_range.start, buffer).is_lt())
440 {
441 cursor.prev();
442 }
443 cursor
444 .item()
445 .filter(|hunk| target.cmp(&hunk.buffer_range.start, buffer).is_ge())
446 }
447
448 /// Returns a patch mapping the provided main buffer snapshot to the base text of this diff.
449 ///
450 /// The returned patch is guaranteed to be accurate for all main buffer points in the provided range,
451 /// but not necessarily for points outside that range.
452 pub fn patch_for_buffer_range<'a>(
453 &'a self,
454 range: RangeInclusive<Point>,
455 buffer: &'a text::BufferSnapshot,
456 ) -> Patch<Point> {
457 if !self.inner.base_text_exists {
458 return Patch::new(vec![Edit {
459 old: Point::zero()..buffer.max_point(),
460 new: Point::zero()..Point::zero(),
461 }]);
462 }
463
464 let mut edits_since_diff = Patch::new(
465 buffer
466 .edits_since::<Point>(&self.inner.buffer_snapshot.version)
467 .collect::<Vec<_>>(),
468 );
469 edits_since_diff.invert();
470
471 let mut start_point = edits_since_diff.old_to_new(*range.start());
472 if let Some(first_edit) = edits_since_diff.edits().first() {
473 start_point = start_point.min(first_edit.new.start);
474 }
475
476 let original_snapshot = self.original_buffer_snapshot();
477 let base_text = self.base_text();
478
479 let mut cursor = self.inner.hunks.cursor(original_snapshot);
480 self.hunk_before_buffer_anchor(
481 original_snapshot.anchor_before(start_point),
482 &mut cursor,
483 original_snapshot,
484 );
485 if cursor.item().is_none() {
486 cursor.next();
487 }
488
489 let mut prefix_edit = cursor.prev_item().map(|prev_hunk| Edit {
490 old: Point::zero()..prev_hunk.buffer_range.end.to_point(original_snapshot),
491 new: Point::zero()..prev_hunk.diff_base_byte_range.end.to_point(base_text),
492 });
493
494 let mut range_end = edits_since_diff.old_to_new(*range.end());
495 if let Some(last_edit) = edits_since_diff.edits().last() {
496 range_end = range_end.max(last_edit.new.end);
497 }
498 let range_end = original_snapshot.anchor_before(range_end);
499
500 let hunk_iter = std::iter::from_fn(move || {
501 if let Some(edit) = prefix_edit.take() {
502 return Some(edit);
503 }
504 let hunk = cursor.item()?;
505 if hunk
506 .buffer_range
507 .start
508 .cmp(&range_end, original_snapshot)
509 .is_gt()
510 {
511 return None;
512 }
513 let edit = Edit {
514 old: hunk.buffer_range.to_point(original_snapshot),
515 new: hunk.diff_base_byte_range.to_point(base_text),
516 };
517 cursor.next();
518 Some(edit)
519 });
520
521 edits_since_diff.compose(hunk_iter)
522 }
523
524 #[cfg(test)]
525 pub(crate) fn patch_for_buffer_range_naive<'a>(
526 &'a self,
527 buffer: &'a text::BufferSnapshot,
528 ) -> Patch<Point> {
529 let original_snapshot = self.original_buffer_snapshot();
530
531 let edits_since: Vec<Edit<Point>> = buffer
532 .edits_since::<Point>(original_snapshot.version())
533 .collect();
534 let mut inverted_edits_since = Patch::new(edits_since);
535 inverted_edits_since.invert();
536
537 inverted_edits_since.compose(
538 self.inner
539 .hunks
540 .iter()
541 .map(|hunk| {
542 let old_start = hunk.buffer_range.start.to_point(original_snapshot);
543 let old_end = hunk.buffer_range.end.to_point(original_snapshot);
544 let new_start = self
545 .base_text()
546 .offset_to_point(hunk.diff_base_byte_range.start);
547 let new_end = self
548 .base_text()
549 .offset_to_point(hunk.diff_base_byte_range.end);
550 Edit {
551 old: old_start..old_end,
552 new: new_start..new_end,
553 }
554 })
555 .chain(
556 if !self.inner.base_text_exists && self.inner.hunks.is_empty() {
557 Some(Edit {
558 old: Point::zero()..original_snapshot.max_point(),
559 new: Point::zero()..Point::zero(),
560 })
561 } else {
562 None
563 },
564 ),
565 )
566 }
567
568 /// Returns a patch mapping the base text of this diff to the provided main buffer snapshot.
569 ///
570 /// The returned patch is guaranteed to be accurate for all base text points in the provided range,
571 /// but not necessarily for points outside that range.
572 pub fn patch_for_base_text_range<'a>(
573 &'a self,
574 range: RangeInclusive<Point>,
575 buffer: &'a text::BufferSnapshot,
576 ) -> Patch<Point> {
577 if !self.inner.base_text_exists {
578 return Patch::new(vec![Edit {
579 old: Point::zero()..Point::zero(),
580 new: Point::zero()..buffer.max_point(),
581 }]);
582 }
583
584 let edits_since_diff = buffer
585 .edits_since::<Point>(&self.inner.buffer_snapshot.version)
586 .collect::<Vec<_>>();
587
588 let mut hunk_patch = Vec::new();
589 let mut cursor = self.inner.hunks.cursor(self.original_buffer_snapshot());
590 let hunk_before = self
591 .hunk_before_base_text_offset(range.start().to_offset(self.base_text()), &mut cursor);
592
593 if let Some(hunk) = hunk_before
594 && let Some(first_edit) = edits_since_diff.first()
595 && hunk
596 .buffer_range
597 .start
598 .to_point(self.original_buffer_snapshot())
599 > first_edit.old.start
600 {
601 cursor.reset();
602 self.hunk_before_buffer_anchor(
603 self.original_buffer_snapshot()
604 .anchor_before(first_edit.old.start),
605 &mut cursor,
606 self.original_buffer_snapshot(),
607 );
608 }
609 if cursor.item().is_none() {
610 cursor.next();
611 }
612 if let Some(prev_hunk) = cursor.prev_item() {
613 hunk_patch.push(Edit {
614 old: Point::zero()
615 ..prev_hunk
616 .diff_base_byte_range
617 .end
618 .to_point(self.base_text()),
619 new: Point::zero()
620 ..prev_hunk
621 .buffer_range
622 .end
623 .to_point(self.original_buffer_snapshot()),
624 })
625 }
626 let range_end = range.end().to_offset(self.base_text());
627 while let Some(hunk) = cursor.item()
628 && (hunk.diff_base_byte_range.start <= range_end
629 || edits_since_diff.last().is_some_and(|last_edit| {
630 hunk.buffer_range
631 .start
632 .to_point(self.original_buffer_snapshot())
633 <= last_edit.old.end
634 }))
635 {
636 hunk_patch.push(Edit {
637 old: hunk.diff_base_byte_range.to_point(self.base_text()),
638 new: hunk.buffer_range.to_point(self.original_buffer_snapshot()),
639 });
640 cursor.next();
641 }
642
643 Patch::new(hunk_patch).compose(edits_since_diff)
644 }
645
646 #[cfg(test)]
647 pub(crate) fn patch_for_base_text_range_naive<'a>(
648 &'a self,
649 buffer: &'a text::BufferSnapshot,
650 ) -> Patch<Point> {
651 let original_snapshot = self.original_buffer_snapshot();
652
653 let mut hunk_edits: Vec<Edit<Point>> = Vec::new();
654 for hunk in self.inner.hunks.iter() {
655 let old_start = self
656 .base_text()
657 .offset_to_point(hunk.diff_base_byte_range.start);
658 let old_end = self
659 .base_text()
660 .offset_to_point(hunk.diff_base_byte_range.end);
661 let new_start = hunk.buffer_range.start.to_point(original_snapshot);
662 let new_end = hunk.buffer_range.end.to_point(original_snapshot);
663 hunk_edits.push(Edit {
664 old: old_start..old_end,
665 new: new_start..new_end,
666 });
667 }
668 if !self.inner.base_text_exists && hunk_edits.is_empty() {
669 hunk_edits.push(Edit {
670 old: Point::zero()..Point::zero(),
671 new: Point::zero()..original_snapshot.max_point(),
672 })
673 }
674 let hunk_patch = Patch::new(hunk_edits);
675
676 hunk_patch.compose(buffer.edits_since::<Point>(original_snapshot.version()))
677 }
678
679 pub fn buffer_point_to_base_text_range(
680 &self,
681 point: Point,
682 buffer: &text::BufferSnapshot,
683 ) -> Range<Point> {
684 let patch = self.patch_for_buffer_range(point..=point, buffer);
685 let edit = patch.edit_for_old_position(point);
686 edit.new
687 }
688
689 pub fn base_text_point_to_buffer_range(
690 &self,
691 point: Point,
692 buffer: &text::BufferSnapshot,
693 ) -> Range<Point> {
694 let patch = self.patch_for_base_text_range(point..=point, buffer);
695 let edit = patch.edit_for_old_position(point);
696 edit.new
697 }
698
699 pub fn buffer_point_to_base_text_point(
700 &self,
701 point: Point,
702 buffer: &text::BufferSnapshot,
703 ) -> Point {
704 let patch = self.patch_for_buffer_range(point..=point, buffer);
705 let edit = patch.edit_for_old_position(point);
706 if point == edit.old.end {
707 edit.new.end
708 } else {
709 edit.new.start
710 }
711 }
712
713 pub fn base_text_point_to_buffer_point(
714 &self,
715 point: Point,
716 buffer: &text::BufferSnapshot,
717 ) -> Point {
718 let patch = self.patch_for_base_text_range(point..=point, buffer);
719 let edit = patch.edit_for_old_position(point);
720 if point == edit.old.end {
721 edit.new.end
722 } else {
723 edit.new.start
724 }
725 }
726}
727
728impl BufferDiffInner<Entity<language::Buffer>> {
729 /// Returns the new index text and new pending hunks.
730 fn stage_or_unstage_hunks_impl(
731 &mut self,
732 unstaged_diff: &Self,
733 stage: bool,
734 hunks: &[DiffHunk],
735 buffer: &text::BufferSnapshot,
736 file_exists: bool,
737 cx: &mut Context<BufferDiff>,
738 ) -> Option<Rope> {
739 let head_text = self
740 .base_text_exists
741 .then(|| self.base_text.read(cx).as_rope().clone());
742 let index_text = unstaged_diff
743 .base_text_exists
744 .then(|| unstaged_diff.base_text.read(cx).as_rope().clone());
745
746 // If the file doesn't exist in either HEAD or the index, then the
747 // entire file must be either created or deleted in the index.
748 let (index_text, head_text) = match (index_text, head_text) {
749 (Some(index_text), Some(head_text)) if file_exists || !stage => (index_text, head_text),
750 (index_text, head_text) => {
751 let (new_index_text, new_status) = if stage {
752 log::debug!("stage all");
753 (
754 file_exists.then(|| buffer.as_rope().clone()),
755 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending,
756 )
757 } else {
758 log::debug!("unstage all");
759 (
760 head_text,
761 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending,
762 )
763 };
764
765 let hunk = PendingHunk {
766 buffer_range: Anchor::min_max_range_for_buffer(buffer.remote_id()),
767 diff_base_byte_range: 0..index_text.map_or(0, |rope| rope.len()),
768 buffer_version: buffer.version().clone(),
769 new_status,
770 };
771 self.pending_hunks = SumTree::from_item(hunk, buffer);
772 return new_index_text;
773 }
774 };
775
776 let mut pending_hunks = SumTree::new(buffer);
777 let mut old_pending_hunks = self.pending_hunks.cursor::<DiffHunkSummary>(buffer);
778
779 // first, merge new hunks into pending_hunks
780 for DiffHunk {
781 buffer_range,
782 diff_base_byte_range,
783 secondary_status,
784 ..
785 } in hunks.iter().cloned()
786 {
787 let preceding_pending_hunks = old_pending_hunks.slice(&buffer_range.start, Bias::Left);
788 pending_hunks.append(preceding_pending_hunks, buffer);
789
790 // Skip all overlapping or adjacent old pending hunks
791 while old_pending_hunks.item().is_some_and(|old_hunk| {
792 old_hunk
793 .buffer_range
794 .start
795 .cmp(&buffer_range.end, buffer)
796 .is_le()
797 }) {
798 old_pending_hunks.next();
799 }
800
801 if (stage && secondary_status == DiffHunkSecondaryStatus::NoSecondaryHunk)
802 || (!stage && secondary_status == DiffHunkSecondaryStatus::HasSecondaryHunk)
803 {
804 continue;
805 }
806
807 pending_hunks.push(
808 PendingHunk {
809 buffer_range,
810 diff_base_byte_range,
811 buffer_version: buffer.version().clone(),
812 new_status: if stage {
813 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
814 } else {
815 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
816 },
817 },
818 buffer,
819 );
820 }
821 // append the remainder
822 pending_hunks.append(old_pending_hunks.suffix(), buffer);
823
824 let mut unstaged_hunk_cursor = unstaged_diff.hunks.cursor::<DiffHunkSummary>(buffer);
825 unstaged_hunk_cursor.next();
826
827 // then, iterate over all pending hunks (both new ones and the existing ones) and compute the edits
828 let mut prev_unstaged_hunk_buffer_end = 0;
829 let mut prev_unstaged_hunk_base_text_end = 0;
830 let mut edits = Vec::<(Range<usize>, String)>::new();
831 let mut pending_hunks_iter = pending_hunks.iter().cloned().peekable();
832 while let Some(PendingHunk {
833 buffer_range,
834 diff_base_byte_range,
835 new_status,
836 ..
837 }) = pending_hunks_iter.next()
838 {
839 // Advance unstaged_hunk_cursor to skip unstaged hunks before current hunk
840 let skipped_unstaged = unstaged_hunk_cursor.slice(&buffer_range.start, Bias::Left);
841
842 if let Some(unstaged_hunk) = skipped_unstaged.last() {
843 prev_unstaged_hunk_base_text_end = unstaged_hunk.diff_base_byte_range.end;
844 prev_unstaged_hunk_buffer_end = unstaged_hunk.buffer_range.end.to_offset(buffer);
845 }
846
847 // Find where this hunk is in the index if it doesn't overlap
848 let mut buffer_offset_range = buffer_range.to_offset(buffer);
849 let start_overshoot = buffer_offset_range.start - prev_unstaged_hunk_buffer_end;
850 let mut index_start = prev_unstaged_hunk_base_text_end + start_overshoot;
851
852 loop {
853 // Merge this hunk with any overlapping unstaged hunks.
854 if let Some(unstaged_hunk) = unstaged_hunk_cursor.item() {
855 let unstaged_hunk_offset_range = unstaged_hunk.buffer_range.to_offset(buffer);
856 if unstaged_hunk_offset_range.start <= buffer_offset_range.end {
857 prev_unstaged_hunk_base_text_end = unstaged_hunk.diff_base_byte_range.end;
858 prev_unstaged_hunk_buffer_end = unstaged_hunk_offset_range.end;
859
860 index_start = index_start.min(unstaged_hunk.diff_base_byte_range.start);
861 buffer_offset_range.start = buffer_offset_range
862 .start
863 .min(unstaged_hunk_offset_range.start);
864 buffer_offset_range.end =
865 buffer_offset_range.end.max(unstaged_hunk_offset_range.end);
866
867 unstaged_hunk_cursor.next();
868 continue;
869 }
870 }
871
872 // If any unstaged hunks were merged, then subsequent pending hunks may
873 // now overlap this hunk. Merge them.
874 if let Some(next_pending_hunk) = pending_hunks_iter.peek() {
875 let next_pending_hunk_offset_range =
876 next_pending_hunk.buffer_range.to_offset(buffer);
877 if next_pending_hunk_offset_range.start <= buffer_offset_range.end {
878 buffer_offset_range.end = buffer_offset_range
879 .end
880 .max(next_pending_hunk_offset_range.end);
881 pending_hunks_iter.next();
882 continue;
883 }
884 }
885
886 break;
887 }
888
889 let end_overshoot = buffer_offset_range
890 .end
891 .saturating_sub(prev_unstaged_hunk_buffer_end);
892 let index_end = prev_unstaged_hunk_base_text_end + end_overshoot;
893 let index_byte_range = index_start..index_end;
894
895 let replacement_text = match new_status {
896 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending => {
897 log::debug!("staging hunk {:?}", buffer_offset_range);
898 buffer
899 .text_for_range(buffer_offset_range)
900 .collect::<String>()
901 }
902 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending => {
903 log::debug!("unstaging hunk {:?}", buffer_offset_range);
904 head_text
905 .chunks_in_range(diff_base_byte_range.clone())
906 .collect::<String>()
907 }
908 _ => {
909 debug_assert!(false);
910 continue;
911 }
912 };
913
914 edits.push((index_byte_range, replacement_text));
915 }
916 drop(pending_hunks_iter);
917 drop(old_pending_hunks);
918 self.pending_hunks = pending_hunks;
919
920 #[cfg(debug_assertions)] // invariants: non-overlapping and sorted
921 {
922 for window in edits.windows(2) {
923 let (range_a, range_b) = (&window[0].0, &window[1].0);
924 debug_assert!(range_a.end < range_b.start);
925 }
926 }
927
928 let mut new_index_text = Rope::new();
929 let mut index_cursor = index_text.cursor(0);
930
931 for (old_range, replacement_text) in edits {
932 new_index_text.append(index_cursor.slice(old_range.start));
933 index_cursor.seek_forward(old_range.end);
934 new_index_text.push(&replacement_text);
935 }
936 new_index_text.append(index_cursor.suffix());
937 Some(new_index_text)
938 }
939}
940
941impl BufferDiffInner<language::BufferSnapshot> {
942 fn hunks_intersecting_range<'a>(
943 &'a self,
944 range: Range<Anchor>,
945 buffer: &'a text::BufferSnapshot,
946 secondary: Option<&'a Self>,
947 ) -> impl 'a + Iterator<Item = DiffHunk> {
948 let range = range.to_offset(buffer);
949 let filter = move |summary: &DiffHunkSummary| {
950 let summary_range = summary.buffer_range.to_offset(buffer);
951 let before_start = summary_range.end < range.start;
952 let after_end = summary_range.start > range.end;
953 !before_start && !after_end
954 };
955 self.hunks_intersecting_range_impl(filter, buffer, secondary)
956 }
957
958 fn hunks_intersecting_range_impl<'a>(
959 &'a self,
960 filter: impl 'a + Fn(&DiffHunkSummary) -> bool,
961 buffer: &'a text::BufferSnapshot,
962 secondary: Option<&'a Self>,
963 ) -> impl 'a + Iterator<Item = DiffHunk> {
964 let anchor_iter = self
965 .hunks
966 .filter::<_, DiffHunkSummary>(buffer, filter)
967 .flat_map(move |hunk| {
968 [
969 (
970 &hunk.buffer_range.start,
971 (
972 hunk.buffer_range.start,
973 hunk.diff_base_byte_range.start,
974 hunk,
975 ),
976 ),
977 (
978 &hunk.buffer_range.end,
979 (hunk.buffer_range.end, hunk.diff_base_byte_range.end, hunk),
980 ),
981 ]
982 });
983
984 let mut pending_hunks_cursor = self.pending_hunks.cursor::<DiffHunkSummary>(buffer);
985 pending_hunks_cursor.next();
986
987 let mut secondary_cursor = None;
988 if let Some(secondary) = secondary.as_ref() {
989 let mut cursor = secondary.hunks.cursor::<DiffHunkSummary>(buffer);
990 cursor.next();
991 secondary_cursor = Some(cursor);
992 }
993
994 let max_point = buffer.max_point();
995 let mut summaries = buffer.summaries_for_anchors_with_payload::<Point, _, _>(anchor_iter);
996 iter::from_fn(move || {
997 loop {
998 let (start_point, (start_anchor, start_base, hunk)) = summaries.next()?;
999 let (mut end_point, (mut end_anchor, end_base, _)) = summaries.next()?;
1000
1001 let base_word_diffs = hunk.base_word_diffs.clone();
1002 let buffer_word_diffs = hunk.buffer_word_diffs.clone();
1003
1004 if !start_anchor.is_valid(buffer) {
1005 continue;
1006 }
1007
1008 if end_point.column > 0 && end_point < max_point {
1009 end_point.row += 1;
1010 end_point.column = 0;
1011 end_anchor = buffer.anchor_before(end_point);
1012 }
1013
1014 let mut secondary_status = DiffHunkSecondaryStatus::NoSecondaryHunk;
1015
1016 let mut has_pending = false;
1017 if start_anchor
1018 .cmp(&pending_hunks_cursor.start().buffer_range.start, buffer)
1019 .is_gt()
1020 {
1021 pending_hunks_cursor.seek_forward(&start_anchor, Bias::Left);
1022 }
1023
1024 if let Some(pending_hunk) = pending_hunks_cursor.item() {
1025 let mut pending_range = pending_hunk.buffer_range.to_point(buffer);
1026 if pending_range.end.column > 0 {
1027 pending_range.end.row += 1;
1028 pending_range.end.column = 0;
1029 }
1030
1031 if pending_range == (start_point..end_point)
1032 && !buffer.has_edits_since_in_range(
1033 &pending_hunk.buffer_version,
1034 start_anchor..end_anchor,
1035 )
1036 {
1037 has_pending = true;
1038 secondary_status = pending_hunk.new_status;
1039 }
1040 }
1041
1042 if let (Some(secondary_cursor), false) = (secondary_cursor.as_mut(), has_pending) {
1043 if start_anchor
1044 .cmp(&secondary_cursor.start().buffer_range.start, buffer)
1045 .is_gt()
1046 {
1047 secondary_cursor.seek_forward(&start_anchor, Bias::Left);
1048 }
1049
1050 if let Some(secondary_hunk) = secondary_cursor.item() {
1051 let mut secondary_range = secondary_hunk.buffer_range.to_point(buffer);
1052 if secondary_range.end.column > 0 {
1053 secondary_range.end.row += 1;
1054 secondary_range.end.column = 0;
1055 }
1056 if secondary_range.is_empty()
1057 && secondary_hunk.diff_base_byte_range.is_empty()
1058 {
1059 // ignore
1060 } else if secondary_range == (start_point..end_point) {
1061 secondary_status = DiffHunkSecondaryStatus::HasSecondaryHunk;
1062 } else if secondary_range.start <= end_point {
1063 secondary_status = DiffHunkSecondaryStatus::OverlapsWithSecondaryHunk;
1064 }
1065 }
1066 }
1067
1068 return Some(DiffHunk {
1069 range: start_point..end_point,
1070 diff_base_byte_range: start_base..end_base,
1071 buffer_range: start_anchor..end_anchor,
1072 base_word_diffs,
1073 buffer_word_diffs,
1074 secondary_status,
1075 });
1076 }
1077 })
1078 }
1079
1080 fn hunks_intersecting_range_rev_impl<'a>(
1081 &'a self,
1082 filter: impl 'a + Fn(&DiffHunkSummary) -> bool,
1083 buffer: &'a text::BufferSnapshot,
1084 ) -> impl 'a + Iterator<Item = DiffHunk> {
1085 let mut cursor = self.hunks.filter::<_, DiffHunkSummary>(buffer, filter);
1086
1087 iter::from_fn(move || {
1088 cursor.prev();
1089
1090 let hunk = cursor.item()?;
1091 let range = hunk.buffer_range.to_point(buffer);
1092
1093 Some(DiffHunk {
1094 range,
1095 diff_base_byte_range: hunk.diff_base_byte_range.clone(),
1096 buffer_range: hunk.buffer_range.clone(),
1097 // The secondary status is not used by callers of this method.
1098 secondary_status: DiffHunkSecondaryStatus::NoSecondaryHunk,
1099 base_word_diffs: hunk.base_word_diffs.clone(),
1100 buffer_word_diffs: hunk.buffer_word_diffs.clone(),
1101 })
1102 })
1103 }
1104}
1105
1106fn build_diff_options(
1107 file: Option<&Arc<dyn File>>,
1108 language: Option<LanguageName>,
1109 language_scope: Option<language::LanguageScope>,
1110 cx: &App,
1111) -> Option<DiffOptions> {
1112 #[cfg(any(test, feature = "test-support"))]
1113 {
1114 if !cx.has_global::<settings::SettingsStore>() {
1115 return Some(DiffOptions {
1116 language_scope,
1117 max_word_diff_line_count: MAX_WORD_DIFF_LINE_COUNT,
1118 ..Default::default()
1119 });
1120 }
1121 }
1122
1123 language_settings(language, file, cx)
1124 .word_diff_enabled
1125 .then_some(DiffOptions {
1126 language_scope,
1127 max_word_diff_line_count: MAX_WORD_DIFF_LINE_COUNT,
1128 ..Default::default()
1129 })
1130}
1131
1132fn compute_hunks(
1133 diff_base: Option<(Arc<str>, Rope)>,
1134 buffer: &text::BufferSnapshot,
1135 diff_options: Option<DiffOptions>,
1136) -> SumTree<InternalDiffHunk> {
1137 let mut tree = SumTree::new(buffer);
1138
1139 if let Some((diff_base, diff_base_rope)) = diff_base {
1140 let buffer_text = buffer.as_rope().to_string();
1141
1142 let mut options = GitOptions::default();
1143 options.context_lines(0);
1144 let patch = GitPatch::from_buffers(
1145 diff_base.as_bytes(),
1146 None,
1147 buffer_text.as_bytes(),
1148 None,
1149 Some(&mut options),
1150 )
1151 .log_err();
1152
1153 // A common case in Zed is that the empty buffer is represented as just a newline,
1154 // but if we just compute a naive diff you get a "preserved" line in the middle,
1155 // which is a bit odd.
1156 if buffer_text == "\n" && diff_base.ends_with("\n") && diff_base.len() > 1 {
1157 tree.push(
1158 InternalDiffHunk {
1159 buffer_range: buffer.anchor_before(0)..buffer.anchor_before(0),
1160 diff_base_byte_range: 0..diff_base.len() - 1,
1161 base_word_diffs: Vec::default(),
1162 buffer_word_diffs: Vec::default(),
1163 },
1164 buffer,
1165 );
1166 return tree;
1167 }
1168
1169 if let Some(patch) = patch {
1170 let mut divergence = 0;
1171 for hunk_index in 0..patch.num_hunks() {
1172 let hunk = process_patch_hunk(
1173 &patch,
1174 hunk_index,
1175 &diff_base_rope,
1176 buffer,
1177 &mut divergence,
1178 diff_options.as_ref(),
1179 );
1180 tree.push(hunk, buffer);
1181 }
1182 }
1183 } else {
1184 tree.push(
1185 InternalDiffHunk {
1186 buffer_range: Anchor::min_max_range_for_buffer(buffer.remote_id()),
1187 diff_base_byte_range: 0..0,
1188 base_word_diffs: Vec::default(),
1189 buffer_word_diffs: Vec::default(),
1190 },
1191 buffer,
1192 );
1193 }
1194
1195 tree
1196}
1197
1198fn compare_hunks(
1199 new_hunks: &SumTree<InternalDiffHunk>,
1200 old_hunks: &SumTree<InternalDiffHunk>,
1201 old_snapshot: &text::BufferSnapshot,
1202 new_snapshot: &text::BufferSnapshot,
1203 old_base_text: &text::BufferSnapshot,
1204 new_base_text: &text::BufferSnapshot,
1205) -> DiffChanged {
1206 let mut new_cursor = new_hunks.cursor::<()>(new_snapshot);
1207 let mut old_cursor = old_hunks.cursor::<()>(new_snapshot);
1208 old_cursor.next();
1209 new_cursor.next();
1210 let mut start = None;
1211 let mut end = None;
1212 let mut base_text_start: Option<Anchor> = None;
1213 let mut base_text_end: Option<Anchor> = None;
1214
1215 let mut last_unchanged_new_hunk_end: Option<text::Anchor> = None;
1216 let mut has_changes = false;
1217 let mut extended_end_candidate: Option<text::Anchor> = None;
1218
1219 loop {
1220 match (new_cursor.item(), old_cursor.item()) {
1221 (Some(new_hunk), Some(old_hunk)) => {
1222 match new_hunk
1223 .buffer_range
1224 .start
1225 .cmp(&old_hunk.buffer_range.start, new_snapshot)
1226 {
1227 Ordering::Less => {
1228 has_changes = true;
1229 extended_end_candidate = None;
1230 start.get_or_insert(new_hunk.buffer_range.start);
1231 base_text_start.get_or_insert(
1232 new_base_text.anchor_before(new_hunk.diff_base_byte_range.start),
1233 );
1234 end.replace(new_hunk.buffer_range.end);
1235 let new_diff_range_end =
1236 new_base_text.anchor_after(new_hunk.diff_base_byte_range.end);
1237 if base_text_end.is_none_or(|base_text_end| {
1238 new_diff_range_end
1239 .cmp(&base_text_end, &new_base_text)
1240 .is_gt()
1241 }) {
1242 base_text_end = Some(new_diff_range_end)
1243 }
1244 new_cursor.next();
1245 }
1246 Ordering::Equal => {
1247 if new_hunk != old_hunk {
1248 has_changes = true;
1249 extended_end_candidate = None;
1250 start.get_or_insert(new_hunk.buffer_range.start);
1251 base_text_start.get_or_insert(
1252 new_base_text.anchor_before(new_hunk.diff_base_byte_range.start),
1253 );
1254 if old_hunk
1255 .buffer_range
1256 .end
1257 .cmp(&new_hunk.buffer_range.end, new_snapshot)
1258 .is_ge()
1259 {
1260 end.replace(old_hunk.buffer_range.end);
1261 } else {
1262 end.replace(new_hunk.buffer_range.end);
1263 }
1264
1265 let old_hunk_diff_base_range_end =
1266 old_base_text.anchor_after(old_hunk.diff_base_byte_range.end);
1267 let new_hunk_diff_base_range_end =
1268 new_base_text.anchor_after(new_hunk.diff_base_byte_range.end);
1269
1270 base_text_end.replace(
1271 *old_hunk_diff_base_range_end
1272 .max(&new_hunk_diff_base_range_end, new_base_text),
1273 );
1274 } else {
1275 if !has_changes {
1276 last_unchanged_new_hunk_end = Some(new_hunk.buffer_range.end);
1277 } else if extended_end_candidate.is_none() {
1278 extended_end_candidate = Some(new_hunk.buffer_range.start);
1279 }
1280 }
1281
1282 new_cursor.next();
1283 old_cursor.next();
1284 }
1285 Ordering::Greater => {
1286 has_changes = true;
1287 extended_end_candidate = None;
1288 start.get_or_insert(old_hunk.buffer_range.start);
1289 base_text_start.get_or_insert(
1290 old_base_text.anchor_after(old_hunk.diff_base_byte_range.start),
1291 );
1292 end.replace(old_hunk.buffer_range.end);
1293 let old_diff_range_end =
1294 old_base_text.anchor_after(old_hunk.diff_base_byte_range.end);
1295 if base_text_end.is_none_or(|base_text_end| {
1296 old_diff_range_end
1297 .cmp(&base_text_end, new_base_text)
1298 .is_gt()
1299 }) {
1300 base_text_end = Some(old_diff_range_end)
1301 }
1302 old_cursor.next();
1303 }
1304 }
1305 }
1306 (Some(new_hunk), None) => {
1307 has_changes = true;
1308 extended_end_candidate = None;
1309 start.get_or_insert(new_hunk.buffer_range.start);
1310 base_text_start
1311 .get_or_insert(new_base_text.anchor_after(new_hunk.diff_base_byte_range.start));
1312 if end.is_none_or(|end| end.cmp(&new_hunk.buffer_range.end, &new_snapshot).is_le())
1313 {
1314 end.replace(new_hunk.buffer_range.end);
1315 }
1316 let new_base_text_end =
1317 new_base_text.anchor_after(new_hunk.diff_base_byte_range.end);
1318 if base_text_end.is_none_or(|base_text_end| {
1319 new_base_text_end.cmp(&base_text_end, new_base_text).is_gt()
1320 }) {
1321 base_text_end = Some(new_base_text_end)
1322 }
1323 new_cursor.next();
1324 }
1325 (None, Some(old_hunk)) => {
1326 has_changes = true;
1327 extended_end_candidate = None;
1328 start.get_or_insert(old_hunk.buffer_range.start);
1329 base_text_start
1330 .get_or_insert(old_base_text.anchor_after(old_hunk.diff_base_byte_range.start));
1331 if end.is_none_or(|end| end.cmp(&old_hunk.buffer_range.end, &new_snapshot).is_le())
1332 {
1333 end.replace(old_hunk.buffer_range.end);
1334 }
1335 let old_base_text_end =
1336 old_base_text.anchor_after(old_hunk.diff_base_byte_range.end);
1337 if base_text_end.is_none_or(|base_text_end| {
1338 old_base_text_end.cmp(&base_text_end, new_base_text).is_gt()
1339 }) {
1340 base_text_end = Some(old_base_text_end);
1341 }
1342 old_cursor.next();
1343 }
1344 (None, None) => break,
1345 }
1346 }
1347
1348 let changed_range = start.zip(end).map(|(start, end)| start..end);
1349 let base_text_changed_range = base_text_start
1350 .zip(base_text_end)
1351 .map(|(start, end)| (start..end).to_offset(new_base_text));
1352
1353 let extended_range = if has_changes && let Some(changed_range) = changed_range.clone() {
1354 let extended_start = *last_unchanged_new_hunk_end
1355 .unwrap_or(text::Anchor::min_for_buffer(new_snapshot.remote_id()))
1356 .min(&changed_range.start, new_snapshot);
1357 let extended_start = new_snapshot
1358 .anchored_edits_since_in_range::<usize>(
1359 &old_snapshot.version(),
1360 extended_start..changed_range.start,
1361 )
1362 .map(|(_, anchors)| anchors.start)
1363 .min_by(|a, b| a.cmp(b, new_snapshot))
1364 .unwrap_or(changed_range.start);
1365
1366 let extended_end = *extended_end_candidate
1367 .unwrap_or(text::Anchor::max_for_buffer(new_snapshot.remote_id()))
1368 .max(&changed_range.end, new_snapshot);
1369 let extended_end = new_snapshot
1370 .anchored_edits_since_in_range::<usize>(
1371 &old_snapshot.version(),
1372 changed_range.end..extended_end,
1373 )
1374 .map(|(_, anchors)| anchors.end)
1375 .max_by(|a, b| a.cmp(b, new_snapshot))
1376 .unwrap_or(changed_range.end);
1377
1378 Some(extended_start..extended_end)
1379 } else {
1380 None
1381 };
1382
1383 DiffChanged {
1384 changed_range,
1385 base_text_changed_range,
1386 extended_range,
1387 }
1388}
1389
1390fn process_patch_hunk(
1391 patch: &GitPatch<'_>,
1392 hunk_index: usize,
1393 diff_base: &Rope,
1394 buffer: &text::BufferSnapshot,
1395 buffer_row_divergence: &mut i64,
1396 diff_options: Option<&DiffOptions>,
1397) -> InternalDiffHunk {
1398 let line_item_count = patch.num_lines_in_hunk(hunk_index).unwrap();
1399 assert!(line_item_count > 0);
1400
1401 let mut first_deletion_buffer_row: Option<u32> = None;
1402 let mut buffer_row_range: Option<Range<u32>> = None;
1403 let mut diff_base_byte_range: Option<Range<usize>> = None;
1404 let mut first_addition_old_row: Option<u32> = None;
1405
1406 for line_index in 0..line_item_count {
1407 let line = patch.line_in_hunk(hunk_index, line_index).unwrap();
1408 let kind = line.origin_value();
1409 let content_offset = line.content_offset() as isize;
1410 let content_len = line.content().len() as isize;
1411 match kind {
1412 GitDiffLineType::Addition => {
1413 if first_addition_old_row.is_none() {
1414 first_addition_old_row = Some(
1415 (line.new_lineno().unwrap() as i64 - *buffer_row_divergence - 1) as u32,
1416 );
1417 }
1418 *buffer_row_divergence += 1;
1419 let row = line.new_lineno().unwrap().saturating_sub(1);
1420
1421 match &mut buffer_row_range {
1422 Some(Range { end, .. }) => *end = row + 1,
1423 None => buffer_row_range = Some(row..row + 1),
1424 }
1425 }
1426 GitDiffLineType::Deletion => {
1427 let end = content_offset + content_len;
1428
1429 match &mut diff_base_byte_range {
1430 Some(head_byte_range) => head_byte_range.end = end as usize,
1431 None => diff_base_byte_range = Some(content_offset as usize..end as usize),
1432 }
1433
1434 if first_deletion_buffer_row.is_none() {
1435 let old_row = line.old_lineno().unwrap().saturating_sub(1);
1436 let row = old_row as i64 + *buffer_row_divergence;
1437 first_deletion_buffer_row = Some(row as u32);
1438 }
1439
1440 *buffer_row_divergence -= 1;
1441 }
1442 _ => {}
1443 }
1444 }
1445
1446 let buffer_row_range = buffer_row_range.unwrap_or_else(|| {
1447 // Pure deletion hunk without addition.
1448 let row = first_deletion_buffer_row.unwrap();
1449 row..row
1450 });
1451 let diff_base_byte_range = diff_base_byte_range.unwrap_or_else(|| {
1452 // Pure addition hunk without deletion.
1453 let row = first_addition_old_row.unwrap();
1454 let offset = diff_base.point_to_offset(Point::new(row, 0));
1455 offset..offset
1456 });
1457
1458 let start = Point::new(buffer_row_range.start, 0);
1459 let end = Point::new(buffer_row_range.end, 0);
1460 let buffer_range = buffer.anchor_before(start)..buffer.anchor_before(end);
1461
1462 let (base_word_diffs, buffer_word_diffs) = if let Some(options) = diff_options {
1463 word_diffs(
1464 diff_base,
1465 diff_base_byte_range.clone(),
1466 buffer,
1467 buffer_range.clone(),
1468 options,
1469 )
1470 } else {
1471 (Vec::new(), Vec::new())
1472 };
1473
1474 InternalDiffHunk {
1475 buffer_range,
1476 diff_base_byte_range,
1477 base_word_diffs,
1478 buffer_word_diffs,
1479 }
1480}
1481
1482fn word_diffs(
1483 diff_base: &Rope,
1484 diff_base_byte_range: Range<usize>,
1485 buffer: &text::BufferSnapshot,
1486 buffer_range: Range<Anchor>,
1487 options: &DiffOptions,
1488) -> (Vec<Range<usize>>, Vec<Range<Anchor>>) {
1489 let buffer_rows = buffer.text_summary_for_range::<Point, _>(buffer_range.clone());
1490 let base_text_rows = diff_base
1491 .cursor(diff_base_byte_range.start)
1492 .summary::<Point>(diff_base_byte_range.end);
1493 if buffer_rows == Point::zero()
1494 || base_text_rows.row != buffer_rows.row
1495 || base_text_rows.row > options.max_word_diff_line_count as u32
1496 {
1497 return (Vec::default(), Vec::default());
1498 }
1499
1500 let base_text: String = diff_base.chunks_in_range(diff_base_byte_range).collect();
1501
1502 let buffer_text: String = buffer.text_for_range(buffer_range.clone()).collect();
1503
1504 let (base_word_diffs, buffer_word_diffs_relative) =
1505 word_diff_ranges(&base_text, &buffer_text, options.clone());
1506
1507 let buffer_start_offset = buffer_range.start.to_offset(buffer);
1508 let buffer_word_diffs = buffer_word_diffs_relative
1509 .into_iter()
1510 .map(|range| {
1511 let start = buffer.anchor_after(buffer_start_offset + range.start);
1512 let end = buffer.anchor_after(buffer_start_offset + range.end);
1513 start..end
1514 })
1515 .collect();
1516
1517 (base_word_diffs, buffer_word_diffs)
1518}
1519
1520impl std::fmt::Debug for BufferDiff {
1521 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
1522 f.debug_struct("BufferChangeSet")
1523 .field("buffer_id", &self.buffer_id)
1524 .finish()
1525 }
1526}
1527
1528#[derive(Clone, Debug, Default)]
1529pub struct DiffChanged {
1530 pub changed_range: Option<Range<text::Anchor>>,
1531 pub base_text_changed_range: Option<Range<usize>>,
1532 pub extended_range: Option<Range<text::Anchor>>,
1533}
1534
1535#[derive(Clone, Debug)]
1536pub enum BufferDiffEvent {
1537 DiffChanged(DiffChanged),
1538 LanguageChanged,
1539 HunksStagedOrUnstaged(Option<Rope>),
1540}
1541
1542impl EventEmitter<BufferDiffEvent> for BufferDiff {}
1543
1544impl BufferDiff {
1545 pub fn new(buffer: &text::BufferSnapshot, cx: &mut App) -> Self {
1546 let base_text = cx.new(|cx| {
1547 let mut buffer = language::Buffer::local("", cx);
1548 buffer.set_capability(Capability::ReadOnly, cx);
1549 buffer
1550 });
1551
1552 BufferDiff {
1553 buffer_id: buffer.remote_id(),
1554 inner: BufferDiffInner {
1555 base_text,
1556 hunks: SumTree::new(buffer),
1557 pending_hunks: SumTree::new(buffer),
1558 base_text_exists: false,
1559 buffer_snapshot: buffer.clone(),
1560 },
1561 secondary_diff: None,
1562 }
1563 }
1564
1565 pub fn new_unchanged(buffer: &text::BufferSnapshot, cx: &mut Context<Self>) -> Self {
1566 let base_text = buffer.text();
1567 let base_text = cx.new(|cx| {
1568 let mut buffer = language::Buffer::local(base_text, cx);
1569 buffer.set_capability(Capability::ReadOnly, cx);
1570 buffer
1571 });
1572
1573 BufferDiff {
1574 buffer_id: buffer.remote_id(),
1575 inner: BufferDiffInner {
1576 base_text,
1577 hunks: SumTree::new(buffer),
1578 pending_hunks: SumTree::new(buffer),
1579 base_text_exists: true,
1580 buffer_snapshot: buffer.clone(),
1581 },
1582 secondary_diff: None,
1583 }
1584 }
1585
1586 #[cfg(any(test, feature = "test-support"))]
1587 pub fn new_with_base_text(
1588 base_text: &str,
1589 buffer: &text::BufferSnapshot,
1590 cx: &mut Context<Self>,
1591 ) -> Self {
1592 let mut this = BufferDiff::new(&buffer, cx);
1593 let mut base_text = base_text.to_owned();
1594 text::LineEnding::normalize(&mut base_text);
1595 let inner = cx.foreground_executor().block_on(this.update_diff(
1596 buffer.clone(),
1597 Some(Arc::from(base_text)),
1598 Some(false),
1599 None,
1600 cx,
1601 ));
1602 this.set_snapshot(inner, &buffer, cx).detach();
1603 this
1604 }
1605
1606 pub fn set_secondary_diff(&mut self, diff: Entity<BufferDiff>) {
1607 self.secondary_diff = Some(diff);
1608 }
1609
1610 pub fn secondary_diff(&self) -> Option<Entity<BufferDiff>> {
1611 self.secondary_diff.clone()
1612 }
1613
1614 pub fn clear_pending_hunks(&mut self, cx: &mut Context<Self>) {
1615 if self.secondary_diff.is_some() {
1616 self.inner.pending_hunks = SumTree::from_summary(DiffHunkSummary {
1617 buffer_range: Anchor::min_min_range_for_buffer(self.buffer_id),
1618 diff_base_byte_range: 0..0,
1619 });
1620 let changed_range = Some(Anchor::min_max_range_for_buffer(self.buffer_id));
1621 let base_text_range = Some(0..self.base_text(cx).len());
1622 cx.emit(BufferDiffEvent::DiffChanged(DiffChanged {
1623 changed_range: changed_range.clone(),
1624 base_text_changed_range: base_text_range,
1625 extended_range: changed_range,
1626 }));
1627 }
1628 }
1629
1630 pub fn stage_or_unstage_hunks(
1631 &mut self,
1632 stage: bool,
1633 hunks: &[DiffHunk],
1634 buffer: &text::BufferSnapshot,
1635 file_exists: bool,
1636 cx: &mut Context<Self>,
1637 ) -> Option<Rope> {
1638 let new_index_text = self
1639 .secondary_diff
1640 .as_ref()?
1641 .update(cx, |secondary_diff, cx| {
1642 self.inner.stage_or_unstage_hunks_impl(
1643 &secondary_diff.inner,
1644 stage,
1645 hunks,
1646 buffer,
1647 file_exists,
1648 cx,
1649 )
1650 });
1651
1652 cx.emit(BufferDiffEvent::HunksStagedOrUnstaged(
1653 new_index_text.clone(),
1654 ));
1655 if let Some((first, last)) = hunks.first().zip(hunks.last()) {
1656 let changed_range = Some(first.buffer_range.start..last.buffer_range.end);
1657 let base_text_changed_range =
1658 Some(first.diff_base_byte_range.start..last.diff_base_byte_range.end);
1659 cx.emit(BufferDiffEvent::DiffChanged(DiffChanged {
1660 changed_range: changed_range.clone(),
1661 base_text_changed_range,
1662 extended_range: changed_range,
1663 }));
1664 }
1665 new_index_text
1666 }
1667
1668 pub fn stage_or_unstage_all_hunks(
1669 &mut self,
1670 stage: bool,
1671 buffer: &text::BufferSnapshot,
1672 file_exists: bool,
1673 cx: &mut Context<Self>,
1674 ) {
1675 let hunks = self
1676 .snapshot(cx)
1677 .hunks_intersecting_range(Anchor::MIN..Anchor::MAX, buffer)
1678 .collect::<Vec<_>>();
1679 let Some(secondary) = self.secondary_diff.clone() else {
1680 return;
1681 };
1682 let secondary = secondary.read(cx).inner.clone();
1683 self.inner
1684 .stage_or_unstage_hunks_impl(&secondary, stage, &hunks, buffer, file_exists, cx);
1685 if let Some((first, last)) = hunks.first().zip(hunks.last()) {
1686 let changed_range = Some(first.buffer_range.start..last.buffer_range.end);
1687 let base_text_changed_range =
1688 Some(first.diff_base_byte_range.start..last.diff_base_byte_range.end);
1689 cx.emit(BufferDiffEvent::DiffChanged(DiffChanged {
1690 changed_range: changed_range.clone(),
1691 base_text_changed_range,
1692 extended_range: changed_range,
1693 }));
1694 }
1695 }
1696
1697 pub fn update_diff(
1698 &self,
1699 buffer: text::BufferSnapshot,
1700 base_text: Option<Arc<str>>,
1701 base_text_change: Option<bool>,
1702 language: Option<Arc<Language>>,
1703 cx: &App,
1704 ) -> Task<BufferDiffUpdate> {
1705 let prev_base_text = self.base_text(cx).as_rope().clone();
1706 let base_text_changed = base_text_change.is_some();
1707 let compute_base_text_edits = base_text_change == Some(true);
1708 let diff_options = build_diff_options(
1709 None,
1710 language.as_ref().map(|l| l.name()),
1711 language.as_ref().map(|l| l.default_scope()),
1712 cx,
1713 );
1714 let buffer_snapshot = buffer.clone();
1715
1716 let base_text_diff_task = if base_text_changed && compute_base_text_edits {
1717 base_text
1718 .as_ref()
1719 .map(|new_text| self.inner.base_text.read(cx).diff(new_text.clone(), cx))
1720 } else {
1721 None
1722 };
1723
1724 let hunk_task = cx.background_executor().spawn({
1725 let buffer_snapshot = buffer_snapshot.clone();
1726 async move {
1727 let base_text_rope = if let Some(base_text) = &base_text {
1728 if base_text_changed {
1729 Rope::from(base_text.as_ref())
1730 } else {
1731 prev_base_text
1732 }
1733 } else {
1734 Rope::new()
1735 };
1736 let base_text_exists = base_text.is_some();
1737 let hunks = compute_hunks(
1738 base_text
1739 .clone()
1740 .map(|base_text| (base_text, base_text_rope.clone())),
1741 &buffer,
1742 diff_options,
1743 );
1744 let base_text = base_text.unwrap_or_default();
1745 BufferDiffInner {
1746 base_text,
1747 hunks,
1748 base_text_exists,
1749 pending_hunks: SumTree::new(&buffer),
1750 buffer_snapshot,
1751 }
1752 }
1753 });
1754
1755 cx.background_executor().spawn(async move {
1756 let (inner, base_text_edits) = match base_text_diff_task {
1757 Some(diff_task) => {
1758 let (inner, diff) = futures::join!(hunk_task, diff_task);
1759 (inner, Some(diff))
1760 }
1761 None => (hunk_task.await, None),
1762 };
1763
1764 BufferDiffUpdate {
1765 inner,
1766 buffer_snapshot,
1767 base_text_edits,
1768 base_text_changed,
1769 }
1770 })
1771 }
1772
1773 #[ztracing::instrument(skip_all)]
1774 pub fn language_changed(
1775 &mut self,
1776 language: Option<Arc<Language>>,
1777 language_registry: Option<Arc<LanguageRegistry>>,
1778 cx: &mut Context<Self>,
1779 ) {
1780 let fut = self.inner.base_text.update(cx, |base_text, cx| {
1781 if let Some(language_registry) = language_registry {
1782 base_text.set_language_registry(language_registry);
1783 }
1784 base_text.set_language_async(language, cx);
1785 base_text.parsing_idle()
1786 });
1787 cx.spawn(async move |this, cx| {
1788 fut.await;
1789 this.update(cx, |_, cx| {
1790 cx.emit(BufferDiffEvent::LanguageChanged);
1791 })
1792 .ok();
1793 })
1794 .detach();
1795 }
1796
1797 fn set_snapshot_with_secondary_inner(
1798 &mut self,
1799 update: BufferDiffUpdate,
1800 buffer: &text::BufferSnapshot,
1801 secondary_diff_change: Option<Range<Anchor>>,
1802 clear_pending_hunks: bool,
1803 cx: &mut Context<Self>,
1804 ) -> impl Future<Output = DiffChanged> + use<> {
1805 log::debug!("set snapshot with secondary {secondary_diff_change:?}");
1806
1807 let old_snapshot = self.snapshot(cx);
1808 let new_state = update.inner;
1809 let base_text_changed = update.base_text_changed;
1810
1811 let state = &mut self.inner;
1812 state.base_text_exists = new_state.base_text_exists;
1813 let should_compare_hunks = update.base_text_edits.is_some() || !base_text_changed;
1814 let parsing_idle = if let Some(diff) = update.base_text_edits {
1815 state.base_text.update(cx, |base_text, cx| {
1816 base_text.set_sync_parse_timeout(None);
1817 base_text.set_capability(Capability::ReadWrite, cx);
1818 base_text.apply_diff(diff, cx);
1819 base_text.set_capability(Capability::ReadOnly, cx);
1820 Some(base_text.parsing_idle())
1821 })
1822 } else if update.base_text_changed {
1823 state.base_text.update(cx, |base_text, cx| {
1824 base_text.set_sync_parse_timeout(None);
1825 base_text.set_capability(Capability::ReadWrite, cx);
1826 base_text.set_text(new_state.base_text.clone(), cx);
1827 base_text.set_capability(Capability::ReadOnly, cx);
1828 Some(base_text.parsing_idle())
1829 })
1830 } else {
1831 None
1832 };
1833
1834 let old_buffer_snapshot = &old_snapshot.inner.buffer_snapshot;
1835 let old_base_snapshot = &old_snapshot.inner.base_text;
1836 let new_base_snapshot = state.base_text.read(cx).snapshot();
1837 let DiffChanged {
1838 mut changed_range,
1839 mut base_text_changed_range,
1840 mut extended_range,
1841 } = match (state.base_text_exists, new_state.base_text_exists) {
1842 (false, false) => DiffChanged::default(),
1843 (true, true) if should_compare_hunks => compare_hunks(
1844 &new_state.hunks,
1845 &old_snapshot.inner.hunks,
1846 old_buffer_snapshot,
1847 buffer,
1848 old_base_snapshot,
1849 &new_base_snapshot,
1850 ),
1851 _ => {
1852 let full_range = text::Anchor::min_max_range_for_buffer(self.buffer_id);
1853 let full_base_range = 0..new_state.base_text.len();
1854 DiffChanged {
1855 changed_range: Some(full_range.clone()),
1856 base_text_changed_range: Some(full_base_range),
1857 extended_range: Some(full_range),
1858 }
1859 }
1860 };
1861 state.hunks = new_state.hunks;
1862 state.buffer_snapshot = update.buffer_snapshot;
1863
1864 if base_text_changed || clear_pending_hunks {
1865 if let Some((first, last)) = state.pending_hunks.first().zip(state.pending_hunks.last())
1866 {
1867 let pending_range = first.buffer_range.start..last.buffer_range.end;
1868 if let Some(range) = &mut changed_range {
1869 range.start = *range.start.min(&pending_range.start, buffer);
1870 range.end = *range.end.max(&pending_range.end, buffer);
1871 } else {
1872 changed_range = Some(pending_range.clone());
1873 }
1874
1875 if let Some(base_text_range) = base_text_changed_range.as_mut() {
1876 base_text_range.start =
1877 base_text_range.start.min(first.diff_base_byte_range.start);
1878 base_text_range.end = base_text_range.end.max(last.diff_base_byte_range.end);
1879 } else {
1880 base_text_changed_range =
1881 Some(first.diff_base_byte_range.start..last.diff_base_byte_range.end);
1882 }
1883
1884 if let Some(ext) = &mut extended_range {
1885 ext.start = *ext.start.min(&pending_range.start, buffer);
1886 ext.end = *ext.end.max(&pending_range.end, buffer);
1887 } else {
1888 extended_range = Some(pending_range);
1889 }
1890 }
1891 state.pending_hunks = SumTree::new(buffer);
1892 }
1893
1894 if let Some(secondary_changed_range) = secondary_diff_change
1895 && let (Some(secondary_hunk_range), Some(secondary_base_range)) =
1896 old_snapshot.range_to_hunk_range(secondary_changed_range, buffer)
1897 {
1898 if let Some(range) = &mut changed_range {
1899 range.start = *secondary_hunk_range.start.min(&range.start, buffer);
1900 range.end = *secondary_hunk_range.end.max(&range.end, buffer);
1901 } else {
1902 changed_range = Some(secondary_hunk_range.clone());
1903 }
1904
1905 if let Some(base_text_range) = base_text_changed_range.as_mut() {
1906 base_text_range.start = secondary_base_range.start.min(base_text_range.start);
1907 base_text_range.end = secondary_base_range.end.max(base_text_range.end);
1908 } else {
1909 base_text_changed_range = Some(secondary_base_range);
1910 }
1911
1912 if let Some(ext) = &mut extended_range {
1913 ext.start = *ext.start.min(&secondary_hunk_range.start, buffer);
1914 ext.end = *ext.end.max(&secondary_hunk_range.end, buffer);
1915 } else {
1916 extended_range = Some(secondary_hunk_range);
1917 }
1918 }
1919
1920 async move {
1921 if let Some(parsing_idle) = parsing_idle {
1922 parsing_idle.await;
1923 }
1924 DiffChanged {
1925 changed_range,
1926 base_text_changed_range,
1927 extended_range,
1928 }
1929 }
1930 }
1931
1932 pub fn set_snapshot(
1933 &mut self,
1934 new_state: BufferDiffUpdate,
1935 buffer: &text::BufferSnapshot,
1936 cx: &mut Context<Self>,
1937 ) -> Task<Option<Range<Anchor>>> {
1938 self.set_snapshot_with_secondary(new_state, buffer, None, false, cx)
1939 }
1940
1941 pub fn set_snapshot_with_secondary(
1942 &mut self,
1943 update: BufferDiffUpdate,
1944 buffer: &text::BufferSnapshot,
1945 secondary_diff_change: Option<Range<Anchor>>,
1946 clear_pending_hunks: bool,
1947 cx: &mut Context<Self>,
1948 ) -> Task<Option<Range<Anchor>>> {
1949 let fut = self.set_snapshot_with_secondary_inner(
1950 update,
1951 buffer,
1952 secondary_diff_change,
1953 clear_pending_hunks,
1954 cx,
1955 );
1956
1957 cx.spawn(async move |this, cx| {
1958 let change = fut.await;
1959 this.update(cx, |_, cx| {
1960 cx.emit(BufferDiffEvent::DiffChanged(change.clone()));
1961 })
1962 .ok();
1963 change.changed_range
1964 })
1965 }
1966
1967 pub fn base_text(&self, cx: &App) -> language::BufferSnapshot {
1968 self.inner.base_text.read(cx).snapshot()
1969 }
1970
1971 pub fn base_text_exists(&self) -> bool {
1972 self.inner.base_text_exists
1973 }
1974
1975 pub fn snapshot(&self, cx: &App) -> BufferDiffSnapshot {
1976 BufferDiffSnapshot {
1977 inner: BufferDiffInner {
1978 hunks: self.inner.hunks.clone(),
1979 pending_hunks: self.inner.pending_hunks.clone(),
1980 base_text: self.inner.base_text.read(cx).snapshot(),
1981 base_text_exists: self.inner.base_text_exists,
1982 buffer_snapshot: self.inner.buffer_snapshot.clone(),
1983 },
1984 secondary_diff: self.secondary_diff.as_ref().map(|diff| {
1985 debug_assert!(diff.read(cx).secondary_diff.is_none());
1986 Arc::new(diff.read(cx).snapshot(cx))
1987 }),
1988 }
1989 }
1990
1991 /// Used in cases where the change set isn't derived from git.
1992 pub fn set_base_text(
1993 &mut self,
1994 base_text: Option<Arc<str>>,
1995 language: Option<Arc<Language>>,
1996 buffer: text::BufferSnapshot,
1997 cx: &mut Context<Self>,
1998 ) -> oneshot::Receiver<()> {
1999 let (tx, rx) = oneshot::channel();
2000 let complete_on_drop = util::defer(|| {
2001 tx.send(()).ok();
2002 });
2003 cx.spawn(async move |this, cx| {
2004 let Some(state) = this
2005 .update(cx, |this, cx| {
2006 this.update_diff(buffer.clone(), base_text, Some(false), language, cx)
2007 })
2008 .log_err()
2009 else {
2010 return;
2011 };
2012 let state = state.await;
2013 if let Some(task) = this
2014 .update(cx, |this, cx| this.set_snapshot(state, &buffer, cx))
2015 .log_err()
2016 {
2017 task.await;
2018 }
2019 drop(complete_on_drop)
2020 })
2021 .detach();
2022 rx
2023 }
2024
2025 pub fn base_text_string(&self, cx: &App) -> Option<String> {
2026 self.inner
2027 .base_text_exists
2028 .then(|| self.inner.base_text.read(cx).text())
2029 }
2030
2031 #[cfg(any(test, feature = "test-support"))]
2032 pub fn recalculate_diff_sync(&mut self, buffer: &text::BufferSnapshot, cx: &mut Context<Self>) {
2033 let language = self.base_text(cx).language().cloned();
2034 let base_text = self.base_text_string(cx).map(|s| s.as_str().into());
2035 let fut = self.update_diff(buffer.clone(), base_text, None, language, cx);
2036 let fg_executor = cx.foreground_executor().clone();
2037 let snapshot = fg_executor.block_on(fut);
2038 let fut = self.set_snapshot_with_secondary_inner(snapshot, buffer, None, false, cx);
2039 let change = fg_executor.block_on(fut);
2040 cx.emit(BufferDiffEvent::DiffChanged(change));
2041 }
2042
2043 pub fn base_text_buffer(&self) -> &Entity<language::Buffer> {
2044 &self.inner.base_text
2045 }
2046}
2047
2048impl DiffHunk {
2049 pub fn is_created_file(&self) -> bool {
2050 self.diff_base_byte_range == (0..0)
2051 && self.buffer_range.start.is_min()
2052 && self.buffer_range.end.is_max()
2053 }
2054
2055 pub fn status(&self) -> DiffHunkStatus {
2056 let kind = if self.buffer_range.start == self.buffer_range.end {
2057 DiffHunkStatusKind::Deleted
2058 } else if self.diff_base_byte_range.is_empty() {
2059 DiffHunkStatusKind::Added
2060 } else {
2061 DiffHunkStatusKind::Modified
2062 };
2063 DiffHunkStatus {
2064 kind,
2065 secondary: self.secondary_status,
2066 }
2067 }
2068}
2069
2070impl DiffHunkStatus {
2071 pub fn has_secondary_hunk(&self) -> bool {
2072 matches!(
2073 self.secondary,
2074 DiffHunkSecondaryStatus::HasSecondaryHunk
2075 | DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
2076 | DiffHunkSecondaryStatus::OverlapsWithSecondaryHunk
2077 )
2078 }
2079
2080 pub fn is_pending(&self) -> bool {
2081 matches!(
2082 self.secondary,
2083 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
2084 | DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
2085 )
2086 }
2087
2088 pub fn is_deleted(&self) -> bool {
2089 self.kind == DiffHunkStatusKind::Deleted
2090 }
2091
2092 pub fn is_added(&self) -> bool {
2093 self.kind == DiffHunkStatusKind::Added
2094 }
2095
2096 pub fn is_modified(&self) -> bool {
2097 self.kind == DiffHunkStatusKind::Modified
2098 }
2099
2100 pub fn added(secondary: DiffHunkSecondaryStatus) -> Self {
2101 Self {
2102 kind: DiffHunkStatusKind::Added,
2103 secondary,
2104 }
2105 }
2106
2107 pub fn modified(secondary: DiffHunkSecondaryStatus) -> Self {
2108 Self {
2109 kind: DiffHunkStatusKind::Modified,
2110 secondary,
2111 }
2112 }
2113
2114 pub fn deleted(secondary: DiffHunkSecondaryStatus) -> Self {
2115 Self {
2116 kind: DiffHunkStatusKind::Deleted,
2117 secondary,
2118 }
2119 }
2120
2121 pub fn deleted_none() -> Self {
2122 Self {
2123 kind: DiffHunkStatusKind::Deleted,
2124 secondary: DiffHunkSecondaryStatus::NoSecondaryHunk,
2125 }
2126 }
2127
2128 pub fn added_none() -> Self {
2129 Self {
2130 kind: DiffHunkStatusKind::Added,
2131 secondary: DiffHunkSecondaryStatus::NoSecondaryHunk,
2132 }
2133 }
2134
2135 pub fn modified_none() -> Self {
2136 Self {
2137 kind: DiffHunkStatusKind::Modified,
2138 secondary: DiffHunkSecondaryStatus::NoSecondaryHunk,
2139 }
2140 }
2141}
2142
2143#[cfg(any(test, feature = "test-support"))]
2144#[track_caller]
2145pub fn assert_hunks<ExpectedText, HunkIter>(
2146 diff_hunks: HunkIter,
2147 buffer: &text::BufferSnapshot,
2148 diff_base: &str,
2149 // Line range, deleted, added, status
2150 expected_hunks: &[(Range<u32>, ExpectedText, ExpectedText, DiffHunkStatus)],
2151) where
2152 HunkIter: Iterator<Item = DiffHunk>,
2153 ExpectedText: AsRef<str>,
2154{
2155 let actual_hunks = diff_hunks
2156 .map(|hunk| {
2157 (
2158 hunk.range.clone(),
2159 &diff_base[hunk.diff_base_byte_range.clone()],
2160 buffer
2161 .text_for_range(hunk.range.clone())
2162 .collect::<String>(),
2163 hunk.status(),
2164 )
2165 })
2166 .collect::<Vec<_>>();
2167
2168 let expected_hunks: Vec<_> = expected_hunks
2169 .iter()
2170 .map(|(line_range, deleted_text, added_text, status)| {
2171 (
2172 Point::new(line_range.start, 0)..Point::new(line_range.end, 0),
2173 deleted_text.as_ref(),
2174 added_text.as_ref().to_string(),
2175 *status,
2176 )
2177 })
2178 .collect();
2179
2180 pretty_assertions::assert_eq!(actual_hunks, expected_hunks);
2181}
2182
2183#[cfg(test)]
2184mod tests {
2185 use std::{fmt::Write as _, sync::mpsc};
2186
2187 use super::*;
2188 use gpui::TestAppContext;
2189 use pretty_assertions::{assert_eq, assert_ne};
2190 use rand::{Rng as _, rngs::StdRng};
2191 use text::{Buffer, BufferId, ReplicaId, Rope};
2192 use unindent::Unindent as _;
2193 use util::test::marked_text_ranges;
2194
2195 #[ctor::ctor]
2196 fn init_logger() {
2197 zlog::init_test();
2198 }
2199
2200 #[gpui::test]
2201 async fn test_buffer_diff_simple(cx: &mut gpui::TestAppContext) {
2202 let diff_base = "
2203 one
2204 two
2205 three
2206 "
2207 .unindent();
2208
2209 let buffer_text = "
2210 one
2211 HELLO
2212 three
2213 "
2214 .unindent();
2215
2216 let mut buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2217 let mut diff = BufferDiffSnapshot::new_sync(&buffer, diff_base.clone(), cx);
2218 assert_hunks(
2219 diff.hunks_intersecting_range(
2220 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2221 &buffer,
2222 ),
2223 &buffer,
2224 &diff_base,
2225 &[(1..2, "two\n", "HELLO\n", DiffHunkStatus::modified_none())],
2226 );
2227
2228 buffer.edit([(0..0, "point five\n")]);
2229 diff = BufferDiffSnapshot::new_sync(&buffer, diff_base.clone(), cx);
2230 assert_hunks(
2231 diff.hunks_intersecting_range(
2232 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2233 &buffer,
2234 ),
2235 &buffer,
2236 &diff_base,
2237 &[
2238 (0..1, "", "point five\n", DiffHunkStatus::added_none()),
2239 (2..3, "two\n", "HELLO\n", DiffHunkStatus::modified_none()),
2240 ],
2241 );
2242
2243 diff = cx.update(|cx| BufferDiff::new(&buffer, cx).snapshot(cx));
2244 assert_hunks::<&str, _>(
2245 diff.hunks_intersecting_range(
2246 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2247 &buffer,
2248 ),
2249 &buffer,
2250 &diff_base,
2251 &[],
2252 );
2253 }
2254
2255 #[gpui::test]
2256 async fn test_buffer_diff_with_secondary(cx: &mut gpui::TestAppContext) {
2257 let head_text = "
2258 zero
2259 one
2260 two
2261 three
2262 four
2263 five
2264 six
2265 seven
2266 eight
2267 nine
2268 "
2269 .unindent();
2270
2271 let index_text = "
2272 zero
2273 one
2274 TWO
2275 three
2276 FOUR
2277 five
2278 six
2279 seven
2280 eight
2281 NINE
2282 "
2283 .unindent();
2284
2285 let buffer_text = "
2286 zero
2287 one
2288 TWO
2289 three
2290 FOUR
2291 FIVE
2292 six
2293 SEVEN
2294 eight
2295 nine
2296 "
2297 .unindent();
2298
2299 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2300 let unstaged_diff = BufferDiffSnapshot::new_sync(&buffer, index_text, cx);
2301 let mut uncommitted_diff = BufferDiffSnapshot::new_sync(&buffer, head_text.clone(), cx);
2302 uncommitted_diff.secondary_diff = Some(Arc::new(unstaged_diff));
2303
2304 let expected_hunks = vec![
2305 (2..3, "two\n", "TWO\n", DiffHunkStatus::modified_none()),
2306 (
2307 4..6,
2308 "four\nfive\n",
2309 "FOUR\nFIVE\n",
2310 DiffHunkStatus::modified(DiffHunkSecondaryStatus::OverlapsWithSecondaryHunk),
2311 ),
2312 (
2313 7..8,
2314 "seven\n",
2315 "SEVEN\n",
2316 DiffHunkStatus::modified(DiffHunkSecondaryStatus::HasSecondaryHunk),
2317 ),
2318 ];
2319
2320 assert_hunks(
2321 uncommitted_diff.hunks_intersecting_range(
2322 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2323 &buffer,
2324 ),
2325 &buffer,
2326 &head_text,
2327 &expected_hunks,
2328 );
2329 }
2330
2331 #[gpui::test]
2332 async fn test_buffer_diff_range(cx: &mut TestAppContext) {
2333 let diff_base = "
2334 one
2335 two
2336 three
2337 four
2338 five
2339 six
2340 seven
2341 eight
2342 nine
2343 ten
2344 "
2345 .unindent();
2346
2347 let buffer_text = "
2348 A
2349 one
2350 B
2351 two
2352 C
2353 three
2354 HELLO
2355 four
2356 five
2357 SIXTEEN
2358 seven
2359 eight
2360 WORLD
2361 nine
2362
2363 ten
2364
2365 "
2366 .unindent();
2367
2368 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2369 let diff = BufferDiffSnapshot::new_sync(buffer.snapshot(), diff_base.clone(), cx);
2370 assert_eq!(
2371 diff.hunks_intersecting_range(
2372 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2373 &buffer
2374 )
2375 .count(),
2376 8
2377 );
2378
2379 assert_hunks(
2380 diff.hunks_intersecting_range(
2381 buffer.anchor_before(Point::new(7, 0))..buffer.anchor_before(Point::new(12, 0)),
2382 &buffer,
2383 ),
2384 &buffer,
2385 &diff_base,
2386 &[
2387 (6..7, "", "HELLO\n", DiffHunkStatus::added_none()),
2388 (9..10, "six\n", "SIXTEEN\n", DiffHunkStatus::modified_none()),
2389 (12..13, "", "WORLD\n", DiffHunkStatus::added_none()),
2390 ],
2391 );
2392 }
2393
2394 #[gpui::test]
2395 async fn test_stage_hunk(cx: &mut TestAppContext) {
2396 struct Example {
2397 name: &'static str,
2398 head_text: String,
2399 index_text: String,
2400 buffer_marked_text: String,
2401 final_index_text: String,
2402 }
2403
2404 let table = [
2405 Example {
2406 name: "uncommitted hunk straddles end of unstaged hunk",
2407 head_text: "
2408 one
2409 two
2410 three
2411 four
2412 five
2413 "
2414 .unindent(),
2415 index_text: "
2416 one
2417 TWO_HUNDRED
2418 three
2419 FOUR_HUNDRED
2420 five
2421 "
2422 .unindent(),
2423 buffer_marked_text: "
2424 ZERO
2425 one
2426 two
2427 «THREE_HUNDRED
2428 FOUR_HUNDRED»
2429 five
2430 SIX
2431 "
2432 .unindent(),
2433 final_index_text: "
2434 one
2435 two
2436 THREE_HUNDRED
2437 FOUR_HUNDRED
2438 five
2439 "
2440 .unindent(),
2441 },
2442 Example {
2443 name: "uncommitted hunk straddles start of unstaged hunk",
2444 head_text: "
2445 one
2446 two
2447 three
2448 four
2449 five
2450 "
2451 .unindent(),
2452 index_text: "
2453 one
2454 TWO_HUNDRED
2455 three
2456 FOUR_HUNDRED
2457 five
2458 "
2459 .unindent(),
2460 buffer_marked_text: "
2461 ZERO
2462 one
2463 «TWO_HUNDRED
2464 THREE_HUNDRED»
2465 four
2466 five
2467 SIX
2468 "
2469 .unindent(),
2470 final_index_text: "
2471 one
2472 TWO_HUNDRED
2473 THREE_HUNDRED
2474 four
2475 five
2476 "
2477 .unindent(),
2478 },
2479 Example {
2480 name: "uncommitted hunk strictly contains unstaged hunks",
2481 head_text: "
2482 one
2483 two
2484 three
2485 four
2486 five
2487 six
2488 seven
2489 "
2490 .unindent(),
2491 index_text: "
2492 one
2493 TWO
2494 THREE
2495 FOUR
2496 FIVE
2497 SIX
2498 seven
2499 "
2500 .unindent(),
2501 buffer_marked_text: "
2502 one
2503 TWO
2504 «THREE_HUNDRED
2505 FOUR
2506 FIVE_HUNDRED»
2507 SIX
2508 seven
2509 "
2510 .unindent(),
2511 final_index_text: "
2512 one
2513 TWO
2514 THREE_HUNDRED
2515 FOUR
2516 FIVE_HUNDRED
2517 SIX
2518 seven
2519 "
2520 .unindent(),
2521 },
2522 Example {
2523 name: "uncommitted deletion hunk",
2524 head_text: "
2525 one
2526 two
2527 three
2528 four
2529 five
2530 "
2531 .unindent(),
2532 index_text: "
2533 one
2534 two
2535 three
2536 four
2537 five
2538 "
2539 .unindent(),
2540 buffer_marked_text: "
2541 one
2542 ˇfive
2543 "
2544 .unindent(),
2545 final_index_text: "
2546 one
2547 five
2548 "
2549 .unindent(),
2550 },
2551 Example {
2552 name: "one unstaged hunk that contains two uncommitted hunks",
2553 head_text: "
2554 one
2555 two
2556
2557 three
2558 four
2559 "
2560 .unindent(),
2561 index_text: "
2562 one
2563 two
2564 three
2565 four
2566 "
2567 .unindent(),
2568 buffer_marked_text: "
2569 «one
2570
2571 three // modified
2572 four»
2573 "
2574 .unindent(),
2575 final_index_text: "
2576 one
2577
2578 three // modified
2579 four
2580 "
2581 .unindent(),
2582 },
2583 Example {
2584 name: "one uncommitted hunk that contains two unstaged hunks",
2585 head_text: "
2586 one
2587 two
2588 three
2589 four
2590 five
2591 "
2592 .unindent(),
2593 index_text: "
2594 ZERO
2595 one
2596 TWO
2597 THREE
2598 FOUR
2599 five
2600 "
2601 .unindent(),
2602 buffer_marked_text: "
2603 «one
2604 TWO_HUNDRED
2605 THREE
2606 FOUR_HUNDRED
2607 five»
2608 "
2609 .unindent(),
2610 final_index_text: "
2611 ZERO
2612 one
2613 TWO_HUNDRED
2614 THREE
2615 FOUR_HUNDRED
2616 five
2617 "
2618 .unindent(),
2619 },
2620 ];
2621
2622 for example in table {
2623 let (buffer_text, ranges) = marked_text_ranges(&example.buffer_marked_text, false);
2624 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2625 let hunk_range =
2626 buffer.anchor_before(ranges[0].start)..buffer.anchor_before(ranges[0].end);
2627
2628 let unstaged_diff =
2629 cx.new(|cx| BufferDiff::new_with_base_text(&example.index_text, &buffer, cx));
2630
2631 let uncommitted_diff = cx.new(|cx| {
2632 let mut diff = BufferDiff::new_with_base_text(&example.head_text, &buffer, cx);
2633 diff.set_secondary_diff(unstaged_diff);
2634 diff
2635 });
2636
2637 uncommitted_diff.update(cx, |diff, cx| {
2638 let hunks = diff
2639 .snapshot(cx)
2640 .hunks_intersecting_range(hunk_range.clone(), &buffer)
2641 .collect::<Vec<_>>();
2642 for hunk in &hunks {
2643 assert_ne!(
2644 hunk.secondary_status,
2645 DiffHunkSecondaryStatus::NoSecondaryHunk
2646 )
2647 }
2648
2649 let new_index_text = diff
2650 .stage_or_unstage_hunks(true, &hunks, &buffer, true, cx)
2651 .unwrap()
2652 .to_string();
2653
2654 let hunks = diff
2655 .snapshot(cx)
2656 .hunks_intersecting_range(hunk_range.clone(), &buffer)
2657 .collect::<Vec<_>>();
2658 for hunk in &hunks {
2659 assert_eq!(
2660 hunk.secondary_status,
2661 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
2662 )
2663 }
2664
2665 pretty_assertions::assert_eq!(
2666 new_index_text,
2667 example.final_index_text,
2668 "example: {}",
2669 example.name
2670 );
2671 });
2672 }
2673 }
2674
2675 #[gpui::test]
2676 async fn test_stage_all_with_nested_hunks(cx: &mut TestAppContext) {
2677 // This test reproduces a crash where staging all hunks would cause an underflow
2678 // when there's one large unstaged hunk containing multiple uncommitted hunks.
2679 let head_text = "
2680 aaa
2681 bbb
2682 ccc
2683 ddd
2684 eee
2685 fff
2686 ggg
2687 hhh
2688 iii
2689 jjj
2690 kkk
2691 lll
2692 "
2693 .unindent();
2694
2695 let index_text = "
2696 aaa
2697 bbb
2698 CCC-index
2699 DDD-index
2700 EEE-index
2701 FFF-index
2702 GGG-index
2703 HHH-index
2704 III-index
2705 JJJ-index
2706 kkk
2707 lll
2708 "
2709 .unindent();
2710
2711 let buffer_text = "
2712 aaa
2713 bbb
2714 ccc-modified
2715 ddd
2716 eee-modified
2717 fff
2718 ggg
2719 hhh-modified
2720 iii
2721 jjj
2722 kkk
2723 lll
2724 "
2725 .unindent();
2726
2727 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2728
2729 let unstaged_diff = cx.new(|cx| BufferDiff::new_with_base_text(&index_text, &buffer, cx));
2730 let uncommitted_diff = cx.new(|cx| {
2731 let mut diff = BufferDiff::new_with_base_text(&head_text, &buffer, cx);
2732 diff.set_secondary_diff(unstaged_diff);
2733 diff
2734 });
2735
2736 uncommitted_diff.update(cx, |diff, cx| {
2737 diff.stage_or_unstage_all_hunks(true, &buffer, true, cx);
2738 });
2739 }
2740
2741 #[gpui::test]
2742 async fn test_toggling_stage_and_unstage_same_hunk(cx: &mut TestAppContext) {
2743 let head_text = "
2744 one
2745 two
2746 three
2747 "
2748 .unindent();
2749 let index_text = head_text.clone();
2750 let buffer_text = "
2751 one
2752 three
2753 "
2754 .unindent();
2755
2756 let buffer = Buffer::new(
2757 ReplicaId::LOCAL,
2758 BufferId::new(1).unwrap(),
2759 buffer_text.clone(),
2760 );
2761 let unstaged_diff = cx.new(|cx| BufferDiff::new_with_base_text(&index_text, &buffer, cx));
2762 let uncommitted_diff = cx.new(|cx| {
2763 let mut diff = BufferDiff::new_with_base_text(&head_text, &buffer, cx);
2764 diff.set_secondary_diff(unstaged_diff.clone());
2765 diff
2766 });
2767
2768 uncommitted_diff.update(cx, |diff, cx| {
2769 let hunk = diff.snapshot(cx).hunks(&buffer).next().unwrap();
2770
2771 let new_index_text = diff
2772 .stage_or_unstage_hunks(true, std::slice::from_ref(&hunk), &buffer, true, cx)
2773 .unwrap()
2774 .to_string();
2775 assert_eq!(new_index_text, buffer_text);
2776
2777 let hunk = diff.snapshot(cx).hunks(&buffer).next().unwrap();
2778 assert_eq!(
2779 hunk.secondary_status,
2780 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
2781 );
2782
2783 let index_text = diff
2784 .stage_or_unstage_hunks(false, &[hunk], &buffer, true, cx)
2785 .unwrap()
2786 .to_string();
2787 assert_eq!(index_text, head_text);
2788
2789 let hunk = diff.snapshot(cx).hunks(&buffer).next().unwrap();
2790 // optimistically unstaged (fine, could also be HasSecondaryHunk)
2791 assert_eq!(
2792 hunk.secondary_status,
2793 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
2794 );
2795 });
2796 }
2797
2798 #[gpui::test]
2799 async fn test_buffer_diff_compare(cx: &mut TestAppContext) {
2800 let base_text = "
2801 zero
2802 one
2803 two
2804 three
2805 four
2806 five
2807 six
2808 seven
2809 eight
2810 nine
2811 "
2812 .unindent();
2813
2814 let buffer_text_1 = "
2815 one
2816 three
2817 four
2818 five
2819 SIX
2820 seven
2821 eight
2822 NINE
2823 "
2824 .unindent();
2825
2826 let mut buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text_1);
2827
2828 let empty_diff = cx.update(|cx| BufferDiff::new(&buffer, cx).snapshot(cx));
2829 let diff_1 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2830 let DiffChanged {
2831 changed_range,
2832 base_text_changed_range,
2833 extended_range: _,
2834 } = compare_hunks(
2835 &diff_1.inner.hunks,
2836 &empty_diff.inner.hunks,
2837 &buffer,
2838 &buffer,
2839 &diff_1.base_text(),
2840 &diff_1.base_text(),
2841 );
2842 let range = changed_range.unwrap();
2843 assert_eq!(range.to_point(&buffer), Point::new(0, 0)..Point::new(8, 0));
2844 let base_text_range = base_text_changed_range.unwrap();
2845 assert_eq!(
2846 base_text_range.to_point(diff_1.base_text()),
2847 Point::new(0, 0)..Point::new(10, 0)
2848 );
2849
2850 // Edit does affects the diff because it recalculates word diffs.
2851 buffer.edit_via_marked_text(
2852 &"
2853 one
2854 three
2855 four
2856 five
2857 «SIX.5»
2858 seven
2859 eight
2860 NINE
2861 "
2862 .unindent(),
2863 );
2864 let diff_2 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2865 let DiffChanged {
2866 changed_range,
2867 base_text_changed_range,
2868 extended_range: _,
2869 } = compare_hunks(
2870 &diff_2.inner.hunks,
2871 &diff_1.inner.hunks,
2872 &buffer,
2873 &buffer,
2874 diff_2.base_text(),
2875 diff_2.base_text(),
2876 );
2877 assert_eq!(
2878 changed_range.unwrap().to_point(&buffer),
2879 Point::new(4, 0)..Point::new(5, 0),
2880 );
2881 assert_eq!(
2882 base_text_changed_range
2883 .unwrap()
2884 .to_point(diff_2.base_text()),
2885 Point::new(6, 0)..Point::new(7, 0),
2886 );
2887
2888 // Edit turns a deletion hunk into a modification.
2889 buffer.edit_via_marked_text(
2890 &"
2891 one
2892 «THREE»
2893 four
2894 five
2895 SIX.5
2896 seven
2897 eight
2898 NINE
2899 "
2900 .unindent(),
2901 );
2902 let diff_3 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2903 let DiffChanged {
2904 changed_range,
2905 base_text_changed_range,
2906 extended_range: _,
2907 } = compare_hunks(
2908 &diff_3.inner.hunks,
2909 &diff_2.inner.hunks,
2910 &buffer,
2911 &buffer,
2912 diff_3.base_text(),
2913 diff_3.base_text(),
2914 );
2915 let range = changed_range.unwrap();
2916 assert_eq!(range.to_point(&buffer), Point::new(1, 0)..Point::new(2, 0));
2917 let base_text_range = base_text_changed_range.unwrap();
2918 assert_eq!(
2919 base_text_range.to_point(diff_3.base_text()),
2920 Point::new(2, 0)..Point::new(4, 0)
2921 );
2922
2923 // Edit turns a modification hunk into a deletion.
2924 buffer.edit_via_marked_text(
2925 &"
2926 one
2927 THREE
2928 four
2929 five«»
2930 seven
2931 eight
2932 NINE
2933 "
2934 .unindent(),
2935 );
2936 let diff_4 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2937 let DiffChanged {
2938 changed_range,
2939 base_text_changed_range,
2940 extended_range: _,
2941 } = compare_hunks(
2942 &diff_4.inner.hunks,
2943 &diff_3.inner.hunks,
2944 &buffer,
2945 &buffer,
2946 diff_4.base_text(),
2947 diff_4.base_text(),
2948 );
2949 let range = changed_range.unwrap();
2950 assert_eq!(range.to_point(&buffer), Point::new(3, 4)..Point::new(4, 0));
2951 let base_text_range = base_text_changed_range.unwrap();
2952 assert_eq!(
2953 base_text_range.to_point(diff_4.base_text()),
2954 Point::new(6, 0)..Point::new(7, 0)
2955 );
2956
2957 // Edit introduces a new insertion hunk.
2958 buffer.edit_via_marked_text(
2959 &"
2960 one
2961 THREE
2962 four«
2963 FOUR.5
2964 »five
2965 seven
2966 eight
2967 NINE
2968 "
2969 .unindent(),
2970 );
2971 let diff_5 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text.clone(), cx);
2972 let DiffChanged {
2973 changed_range,
2974 base_text_changed_range,
2975 extended_range: _,
2976 } = compare_hunks(
2977 &diff_5.inner.hunks,
2978 &diff_4.inner.hunks,
2979 &buffer,
2980 &buffer,
2981 diff_5.base_text(),
2982 diff_5.base_text(),
2983 );
2984 let range = changed_range.unwrap();
2985 assert_eq!(range.to_point(&buffer), Point::new(3, 0)..Point::new(4, 0));
2986 let base_text_range = base_text_changed_range.unwrap();
2987 assert_eq!(
2988 base_text_range.to_point(diff_5.base_text()),
2989 Point::new(5, 0)..Point::new(5, 0)
2990 );
2991
2992 // Edit removes a hunk.
2993 buffer.edit_via_marked_text(
2994 &"
2995 one
2996 THREE
2997 four
2998 FOUR.5
2999 five
3000 seven
3001 eight
3002 «nine»
3003 "
3004 .unindent(),
3005 );
3006 let diff_6 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text.clone(), cx);
3007 let DiffChanged {
3008 changed_range,
3009 base_text_changed_range,
3010 extended_range: _,
3011 } = compare_hunks(
3012 &diff_6.inner.hunks,
3013 &diff_5.inner.hunks,
3014 &buffer,
3015 &buffer,
3016 diff_6.base_text(),
3017 diff_6.base_text(),
3018 );
3019 let range = changed_range.unwrap();
3020 assert_eq!(range.to_point(&buffer), Point::new(7, 0)..Point::new(8, 0));
3021 let base_text_range = base_text_changed_range.unwrap();
3022 assert_eq!(
3023 base_text_range.to_point(diff_6.base_text()),
3024 Point::new(9, 0)..Point::new(10, 0)
3025 );
3026
3027 buffer.edit_via_marked_text(
3028 &"
3029 one
3030 THREE
3031 four«»
3032 five
3033 seven
3034 eight
3035 «NINE»
3036 "
3037 .unindent(),
3038 );
3039
3040 let diff_7 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text.clone(), cx);
3041 let DiffChanged {
3042 changed_range,
3043 base_text_changed_range,
3044 extended_range: _,
3045 } = compare_hunks(
3046 &diff_7.inner.hunks,
3047 &diff_6.inner.hunks,
3048 &buffer,
3049 &buffer,
3050 diff_7.base_text(),
3051 diff_7.base_text(),
3052 );
3053 let range = changed_range.unwrap();
3054 assert_eq!(range.to_point(&buffer), Point::new(2, 4)..Point::new(7, 0));
3055 let base_text_range = base_text_changed_range.unwrap();
3056 assert_eq!(
3057 base_text_range.to_point(diff_7.base_text()),
3058 Point::new(5, 0)..Point::new(10, 0)
3059 );
3060
3061 buffer.edit_via_marked_text(
3062 &"
3063 one
3064 THREE
3065 four
3066 five«»seven
3067 eight
3068 NINE
3069 "
3070 .unindent(),
3071 );
3072
3073 let diff_8 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text, cx);
3074 let DiffChanged {
3075 changed_range,
3076 base_text_changed_range,
3077 extended_range: _,
3078 } = compare_hunks(
3079 &diff_8.inner.hunks,
3080 &diff_7.inner.hunks,
3081 &buffer,
3082 &buffer,
3083 diff_8.base_text(),
3084 diff_8.base_text(),
3085 );
3086 let range = changed_range.unwrap();
3087 assert_eq!(range.to_point(&buffer), Point::new(3, 0)..Point::new(3, 4));
3088 let base_text_range = base_text_changed_range.unwrap();
3089 assert_eq!(
3090 base_text_range.to_point(diff_8.base_text()),
3091 Point::new(5, 0)..Point::new(8, 0)
3092 );
3093 }
3094
3095 #[gpui::test(iterations = 100)]
3096 async fn test_staging_and_unstaging_hunks(cx: &mut TestAppContext, mut rng: StdRng) {
3097 fn gen_line(rng: &mut StdRng) -> String {
3098 if rng.random_bool(0.2) {
3099 "\n".to_owned()
3100 } else {
3101 let c = rng.random_range('A'..='Z');
3102 format!("{c}{c}{c}\n")
3103 }
3104 }
3105
3106 fn gen_working_copy(rng: &mut StdRng, head: &str) -> String {
3107 let mut old_lines = {
3108 let mut old_lines = Vec::new();
3109 let old_lines_iter = head.lines();
3110 for line in old_lines_iter {
3111 assert!(!line.ends_with("\n"));
3112 old_lines.push(line.to_owned());
3113 }
3114 if old_lines.last().is_some_and(|line| line.is_empty()) {
3115 old_lines.pop();
3116 }
3117 old_lines.into_iter()
3118 };
3119 let mut result = String::new();
3120 let unchanged_count = rng.random_range(0..=old_lines.len());
3121 result +=
3122 &old_lines
3123 .by_ref()
3124 .take(unchanged_count)
3125 .fold(String::new(), |mut s, line| {
3126 writeln!(&mut s, "{line}").unwrap();
3127 s
3128 });
3129 while old_lines.len() > 0 {
3130 let deleted_count = rng.random_range(0..=old_lines.len());
3131 let _advance = old_lines
3132 .by_ref()
3133 .take(deleted_count)
3134 .map(|line| line.len() + 1)
3135 .sum::<usize>();
3136 let minimum_added = if deleted_count == 0 { 1 } else { 0 };
3137 let added_count = rng.random_range(minimum_added..=5);
3138 let addition = (0..added_count).map(|_| gen_line(rng)).collect::<String>();
3139 result += &addition;
3140
3141 if old_lines.len() > 0 {
3142 let blank_lines = old_lines.clone().take_while(|line| line.is_empty()).count();
3143 if blank_lines == old_lines.len() {
3144 break;
3145 };
3146 let unchanged_count =
3147 rng.random_range((blank_lines + 1).max(1)..=old_lines.len());
3148 result += &old_lines.by_ref().take(unchanged_count).fold(
3149 String::new(),
3150 |mut s, line| {
3151 writeln!(&mut s, "{line}").unwrap();
3152 s
3153 },
3154 );
3155 }
3156 }
3157 result
3158 }
3159
3160 fn uncommitted_diff(
3161 working_copy: &language::BufferSnapshot,
3162 index_text: &Rope,
3163 head_text: String,
3164 cx: &mut TestAppContext,
3165 ) -> Entity<BufferDiff> {
3166 let secondary = cx.new(|cx| {
3167 BufferDiff::new_with_base_text(&index_text.to_string(), &working_copy.text, cx)
3168 });
3169 cx.new(|cx| {
3170 let mut diff = BufferDiff::new_with_base_text(&head_text, &working_copy.text, cx);
3171 diff.secondary_diff = Some(secondary);
3172 diff
3173 })
3174 }
3175
3176 let operations = std::env::var("OPERATIONS")
3177 .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
3178 .unwrap_or(10);
3179
3180 let rng = &mut rng;
3181 let head_text = ('a'..='z').fold(String::new(), |mut s, c| {
3182 writeln!(&mut s, "{c}{c}{c}").unwrap();
3183 s
3184 });
3185 let working_copy = gen_working_copy(rng, &head_text);
3186 let working_copy = cx.new(|cx| {
3187 language::Buffer::local_normalized(
3188 Rope::from(working_copy.as_str()),
3189 text::LineEnding::default(),
3190 cx,
3191 )
3192 });
3193 let working_copy = working_copy.read_with(cx, |working_copy, _| working_copy.snapshot());
3194 let mut index_text = if rng.random() {
3195 Rope::from(head_text.as_str())
3196 } else {
3197 working_copy.as_rope().clone()
3198 };
3199
3200 let mut diff = uncommitted_diff(&working_copy, &index_text, head_text.clone(), cx);
3201 let mut hunks = diff.update(cx, |diff, cx| {
3202 diff.snapshot(cx)
3203 .hunks_intersecting_range(
3204 Anchor::min_max_range_for_buffer(diff.buffer_id),
3205 &working_copy,
3206 )
3207 .collect::<Vec<_>>()
3208 });
3209 if hunks.is_empty() {
3210 return;
3211 }
3212
3213 for _ in 0..operations {
3214 let i = rng.random_range(0..hunks.len());
3215 let hunk = &mut hunks[i];
3216 let hunk_to_change = hunk.clone();
3217 let stage = match hunk.secondary_status {
3218 DiffHunkSecondaryStatus::HasSecondaryHunk => {
3219 hunk.secondary_status = DiffHunkSecondaryStatus::NoSecondaryHunk;
3220 true
3221 }
3222 DiffHunkSecondaryStatus::NoSecondaryHunk => {
3223 hunk.secondary_status = DiffHunkSecondaryStatus::HasSecondaryHunk;
3224 false
3225 }
3226 _ => unreachable!(),
3227 };
3228
3229 index_text = diff.update(cx, |diff, cx| {
3230 diff.stage_or_unstage_hunks(stage, &[hunk_to_change], &working_copy, true, cx)
3231 .unwrap()
3232 });
3233
3234 diff = uncommitted_diff(&working_copy, &index_text, head_text.clone(), cx);
3235 let found_hunks = diff.update(cx, |diff, cx| {
3236 diff.snapshot(cx)
3237 .hunks_intersecting_range(
3238 Anchor::min_max_range_for_buffer(diff.buffer_id),
3239 &working_copy,
3240 )
3241 .collect::<Vec<_>>()
3242 });
3243 assert_eq!(hunks.len(), found_hunks.len());
3244
3245 for (expected_hunk, found_hunk) in hunks.iter().zip(&found_hunks) {
3246 assert_eq!(
3247 expected_hunk.buffer_range.to_point(&working_copy),
3248 found_hunk.buffer_range.to_point(&working_copy)
3249 );
3250 assert_eq!(
3251 expected_hunk.diff_base_byte_range,
3252 found_hunk.diff_base_byte_range
3253 );
3254 assert_eq!(expected_hunk.secondary_status, found_hunk.secondary_status);
3255 }
3256 hunks = found_hunks;
3257 }
3258 }
3259
3260 #[gpui::test]
3261 async fn test_changed_ranges(cx: &mut gpui::TestAppContext) {
3262 let base_text = "
3263 one
3264 two
3265 three
3266 four
3267 five
3268 six
3269 "
3270 .unindent();
3271 let buffer_text = "
3272 one
3273 TWO
3274 three
3275 four
3276 FIVE
3277 six
3278 "
3279 .unindent();
3280 let buffer = cx.new(|cx| language::Buffer::local(buffer_text, cx));
3281 let diff = cx.new(|cx| {
3282 BufferDiff::new_with_base_text(&base_text, &buffer.read(cx).text_snapshot(), cx)
3283 });
3284 cx.run_until_parked();
3285 let (tx, rx) = mpsc::channel();
3286 let subscription =
3287 cx.update(|cx| cx.subscribe(&diff, move |_, event, _| tx.send(event.clone()).unwrap()));
3288
3289 let snapshot = buffer.update(cx, |buffer, cx| {
3290 buffer.set_text(
3291 "
3292 ONE
3293 TWO
3294 THREE
3295 FOUR
3296 FIVE
3297 SIX
3298 "
3299 .unindent(),
3300 cx,
3301 );
3302 buffer.text_snapshot()
3303 });
3304 let update = diff
3305 .update(cx, |diff, cx| {
3306 diff.update_diff(
3307 snapshot.clone(),
3308 Some(base_text.as_str().into()),
3309 None,
3310 None,
3311 cx,
3312 )
3313 })
3314 .await;
3315 diff.update(cx, |diff, cx| diff.set_snapshot(update, &snapshot, cx))
3316 .await;
3317 cx.run_until_parked();
3318 drop(subscription);
3319 let events = rx.into_iter().collect::<Vec<_>>();
3320 match events.as_slice() {
3321 [
3322 BufferDiffEvent::DiffChanged(DiffChanged {
3323 changed_range: _,
3324 base_text_changed_range,
3325 extended_range: _,
3326 }),
3327 ] => {
3328 // TODO(cole) this seems like it should pass but currently fails (see compare_hunks)
3329 // assert_eq!(
3330 // *changed_range,
3331 // Some(Anchor::min_max_range_for_buffer(
3332 // buffer.read_with(cx, |buffer, _| buffer.remote_id())
3333 // ))
3334 // );
3335 assert_eq!(*base_text_changed_range, Some(0..base_text.len()));
3336 }
3337 _ => panic!("unexpected events: {:?}", events),
3338 }
3339 }
3340
3341 #[gpui::test]
3342 async fn test_extended_range(cx: &mut TestAppContext) {
3343 let base_text = "
3344 aaa
3345 bbb
3346
3347
3348
3349
3350
3351 ccc
3352 ddd
3353 "
3354 .unindent();
3355
3356 let buffer_text = "
3357 aaa
3358 bbb
3359
3360
3361
3362
3363
3364 CCC
3365 ddd
3366 "
3367 .unindent();
3368
3369 let mut buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
3370 let old_buffer = buffer.snapshot().clone();
3371 let diff_a = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
3372
3373 buffer.edit([(Point::new(1, 3)..Point::new(1, 3), "\n")]);
3374 let diff_b = BufferDiffSnapshot::new_sync(&buffer, base_text, cx);
3375
3376 let DiffChanged {
3377 changed_range,
3378 base_text_changed_range: _,
3379 extended_range,
3380 } = compare_hunks(
3381 &diff_b.inner.hunks,
3382 &diff_a.inner.hunks,
3383 &old_buffer,
3384 &buffer,
3385 &diff_a.base_text(),
3386 &diff_a.base_text(),
3387 );
3388
3389 let changed_range = changed_range.unwrap();
3390 assert_eq!(
3391 changed_range.to_point(&buffer),
3392 Point::new(7, 0)..Point::new(9, 0),
3393 "changed_range should span from old hunk position to new hunk end"
3394 );
3395
3396 let extended_range = extended_range.unwrap();
3397 assert_eq!(
3398 extended_range.start.to_point(&buffer),
3399 Point::new(1, 3),
3400 "extended_range.start should extend to include the edit outside changed_range"
3401 );
3402 assert_eq!(
3403 extended_range.end.to_point(&buffer),
3404 Point::new(9, 0),
3405 "extended_range.end should collapse to changed_range.end when no edits in end margin"
3406 );
3407
3408 let base_text_2 = "
3409 one
3410 two
3411 three
3412 four
3413 five
3414 six
3415 seven
3416 eight
3417 "
3418 .unindent();
3419
3420 let buffer_text_2 = "
3421 ONE
3422 two
3423 THREE
3424 four
3425 FIVE
3426 six
3427 SEVEN
3428 eight
3429 "
3430 .unindent();
3431
3432 let mut buffer_2 = Buffer::new(ReplicaId::LOCAL, BufferId::new(2).unwrap(), buffer_text_2);
3433 let old_buffer_2 = buffer_2.snapshot().clone();
3434 let diff_2a = BufferDiffSnapshot::new_sync(&buffer_2, base_text_2.clone(), cx);
3435
3436 buffer_2.edit([(Point::new(4, 0)..Point::new(4, 4), "FIVE_CHANGED")]);
3437 let diff_2b = BufferDiffSnapshot::new_sync(&buffer_2, base_text_2, cx);
3438
3439 let DiffChanged {
3440 changed_range,
3441 base_text_changed_range: _,
3442 extended_range,
3443 } = compare_hunks(
3444 &diff_2b.inner.hunks,
3445 &diff_2a.inner.hunks,
3446 &old_buffer_2,
3447 &buffer_2,
3448 &diff_2a.base_text(),
3449 &diff_2a.base_text(),
3450 );
3451
3452 let changed_range = changed_range.unwrap();
3453 assert_eq!(
3454 changed_range.to_point(&buffer_2),
3455 Point::new(4, 0)..Point::new(5, 0),
3456 "changed_range should be just the hunk that changed (FIVE)"
3457 );
3458
3459 let extended_range = extended_range.unwrap();
3460 assert_eq!(
3461 extended_range.to_point(&buffer_2),
3462 Point::new(4, 0)..Point::new(5, 0),
3463 "extended_range should equal changed_range when edit is within the hunk"
3464 );
3465 }
3466
3467 #[gpui::test]
3468 async fn test_buffer_diff_compare_with_base_text_change(_cx: &mut TestAppContext) {
3469 // Use a shared base text buffer so that anchors from old and new snapshots
3470 // share the same remote_id and resolve correctly across versions.
3471 let initial_base = "aaa\nbbb\nccc\nddd\neee\n";
3472 let mut base_text_buffer = Buffer::new(
3473 ReplicaId::LOCAL,
3474 BufferId::new(99).unwrap(),
3475 initial_base.to_string(),
3476 );
3477
3478 // --- Scenario 1: Base text gains a line, producing a new deletion hunk ---
3479 //
3480 // Buffer has a modification (ccc → CCC). When the base text gains
3481 // a new line "XXX" after "aaa", the diff now also contains a
3482 // deletion for that line, and the modification hunk shifts in the
3483 // base text.
3484 let buffer_text_1 = "aaa\nbbb\nCCC\nddd\neee\n";
3485 let buffer = Buffer::new(
3486 ReplicaId::LOCAL,
3487 BufferId::new(1).unwrap(),
3488 buffer_text_1.to_string(),
3489 );
3490
3491 let old_base_snapshot_1 = base_text_buffer.snapshot().clone();
3492 let old_hunks_1 = compute_hunks(
3493 Some((Arc::from(initial_base), Rope::from(initial_base))),
3494 buffer.snapshot(),
3495 None,
3496 );
3497
3498 // Insert "XXX\n" after "aaa\n" in the base text.
3499 base_text_buffer.edit([(4..4, "XXX\n")]);
3500 let new_base_str_1: Arc<str> = Arc::from(base_text_buffer.text().as_str());
3501 let new_base_snapshot_1 = base_text_buffer.snapshot();
3502
3503 let new_hunks_1 = compute_hunks(
3504 Some((new_base_str_1.clone(), Rope::from(new_base_str_1.as_ref()))),
3505 buffer.snapshot(),
3506 None,
3507 );
3508
3509 let DiffChanged {
3510 changed_range,
3511 base_text_changed_range,
3512 extended_range: _,
3513 } = compare_hunks(
3514 &new_hunks_1,
3515 &old_hunks_1,
3516 &buffer.snapshot(),
3517 &buffer.snapshot(),
3518 &old_base_snapshot_1,
3519 &new_base_snapshot_1,
3520 );
3521
3522 // The new deletion hunk (XXX) starts at buffer row 1 and the
3523 // modification hunk (ccc → CCC) now has a different
3524 // diff_base_byte_range, so the changed range spans both.
3525 let range = changed_range.unwrap();
3526 assert_eq!(range.to_point(&buffer), Point::new(1, 0)..Point::new(3, 0),);
3527 let base_range = base_text_changed_range.unwrap();
3528 assert_eq!(
3529 base_range.to_point(&new_base_snapshot_1),
3530 Point::new(1, 0)..Point::new(4, 0),
3531 );
3532
3533 // --- Scenario 2: Base text changes to match the buffer (hunk disappears) ---
3534 //
3535 // Start fresh with a simple base text.
3536 let simple_base = "one\ntwo\nthree\n";
3537 let mut base_buf_2 = Buffer::new(
3538 ReplicaId::LOCAL,
3539 BufferId::new(100).unwrap(),
3540 simple_base.to_string(),
3541 );
3542
3543 let buffer_text_2 = "one\nTWO\nthree\n";
3544 let buffer_2 = Buffer::new(
3545 ReplicaId::LOCAL,
3546 BufferId::new(2).unwrap(),
3547 buffer_text_2.to_string(),
3548 );
3549
3550 let old_base_snapshot_2 = base_buf_2.snapshot().clone();
3551 let old_hunks_2 = compute_hunks(
3552 Some((Arc::from(simple_base), Rope::from(simple_base))),
3553 buffer_2.snapshot(),
3554 None,
3555 );
3556
3557 // The base text is edited so "two" becomes "TWO", now matching the buffer.
3558 base_buf_2.edit([(4..7, "TWO")]);
3559 let new_base_str_2: Arc<str> = Arc::from(base_buf_2.text().as_str());
3560 let new_base_snapshot_2 = base_buf_2.snapshot();
3561
3562 let new_hunks_2 = compute_hunks(
3563 Some((new_base_str_2.clone(), Rope::from(new_base_str_2.as_ref()))),
3564 buffer_2.snapshot(),
3565 None,
3566 );
3567
3568 let DiffChanged {
3569 changed_range,
3570 base_text_changed_range,
3571 extended_range: _,
3572 } = compare_hunks(
3573 &new_hunks_2,
3574 &old_hunks_2,
3575 &buffer_2.snapshot(),
3576 &buffer_2.snapshot(),
3577 &old_base_snapshot_2,
3578 &new_base_snapshot_2,
3579 );
3580
3581 // The old modification hunk (two → TWO) is now gone because the
3582 // base text matches the buffer. The changed range covers where the
3583 // old hunk used to be.
3584 let range = changed_range.unwrap();
3585 assert_eq!(
3586 range.to_point(&buffer_2),
3587 Point::new(1, 0)..Point::new(2, 0),
3588 );
3589 let base_range = base_text_changed_range.unwrap();
3590 // The old hunk's diff_base_byte_range covered "two\n" (bytes 4..8).
3591 // anchor_after(4) is right-biased at the start of the deleted "two",
3592 // so after the edit replacing "two" with "TWO" it resolves past the
3593 // insertion to Point(1, 3).
3594 assert_eq!(
3595 base_range.to_point(&new_base_snapshot_2),
3596 Point::new(1, 3)..Point::new(2, 0),
3597 );
3598
3599 // --- Scenario 3: Base text edit changes one hunk but not another ---
3600 //
3601 // Two modification hunks exist. Only one of them is resolved by
3602 // the base text change; the other remains identical.
3603 let base_3 = "aaa\nbbb\nccc\nddd\neee\n";
3604 let mut base_buf_3 = Buffer::new(
3605 ReplicaId::LOCAL,
3606 BufferId::new(101).unwrap(),
3607 base_3.to_string(),
3608 );
3609
3610 let buffer_text_3 = "aaa\nBBB\nccc\nDDD\neee\n";
3611 let buffer_3 = Buffer::new(
3612 ReplicaId::LOCAL,
3613 BufferId::new(3).unwrap(),
3614 buffer_text_3.to_string(),
3615 );
3616
3617 let old_base_snapshot_3 = base_buf_3.snapshot().clone();
3618 let old_hunks_3 = compute_hunks(
3619 Some((Arc::from(base_3), Rope::from(base_3))),
3620 buffer_3.snapshot(),
3621 None,
3622 );
3623
3624 // Change "ddd" to "DDD" in the base text so that hunk disappears,
3625 // but "bbb" stays, so its hunk remains.
3626 base_buf_3.edit([(12..15, "DDD")]);
3627 let new_base_str_3: Arc<str> = Arc::from(base_buf_3.text().as_str());
3628 let new_base_snapshot_3 = base_buf_3.snapshot();
3629
3630 let new_hunks_3 = compute_hunks(
3631 Some((new_base_str_3.clone(), Rope::from(new_base_str_3.as_ref()))),
3632 buffer_3.snapshot(),
3633 None,
3634 );
3635
3636 let DiffChanged {
3637 changed_range,
3638 base_text_changed_range,
3639 extended_range: _,
3640 } = compare_hunks(
3641 &new_hunks_3,
3642 &old_hunks_3,
3643 &buffer_3.snapshot(),
3644 &buffer_3.snapshot(),
3645 &old_base_snapshot_3,
3646 &new_base_snapshot_3,
3647 );
3648
3649 // Only the second hunk (ddd → DDD) disappeared; the first hunk
3650 // (bbb → BBB) is unchanged, so the changed range covers only line 3.
3651 let range = changed_range.unwrap();
3652 assert_eq!(
3653 range.to_point(&buffer_3),
3654 Point::new(3, 0)..Point::new(4, 0),
3655 );
3656 let base_range = base_text_changed_range.unwrap();
3657 // anchor_after(12) is right-biased at the start of deleted "ddd",
3658 // so after the edit replacing "ddd" with "DDD" it resolves past
3659 // the insertion to Point(3, 3).
3660 assert_eq!(
3661 base_range.to_point(&new_base_snapshot_3),
3662 Point::new(3, 3)..Point::new(4, 0),
3663 );
3664
3665 // --- Scenario 4: Both buffer and base text change simultaneously ---
3666 //
3667 // The buffer gains an edit that introduces a new hunk while the
3668 // base text also changes.
3669 let base_4 = "alpha\nbeta\ngamma\ndelta\n";
3670 let mut base_buf_4 = Buffer::new(
3671 ReplicaId::LOCAL,
3672 BufferId::new(102).unwrap(),
3673 base_4.to_string(),
3674 );
3675
3676 let buffer_text_4 = "alpha\nBETA\ngamma\ndelta\n";
3677 let mut buffer_4 = Buffer::new(
3678 ReplicaId::LOCAL,
3679 BufferId::new(4).unwrap(),
3680 buffer_text_4.to_string(),
3681 );
3682
3683 let old_base_snapshot_4 = base_buf_4.snapshot().clone();
3684 let old_buffer_snapshot_4 = buffer_4.snapshot().clone();
3685 let old_hunks_4 = compute_hunks(
3686 Some((Arc::from(base_4), Rope::from(base_4))),
3687 buffer_4.snapshot(),
3688 None,
3689 );
3690
3691 // Edit the buffer: change "delta" to "DELTA" (new modification hunk).
3692 buffer_4.edit_via_marked_text(
3693 &"
3694 alpha
3695 BETA
3696 gamma
3697 «DELTA»
3698 "
3699 .unindent(),
3700 );
3701
3702 // Edit the base text: change "beta" to "BETA" (resolves that hunk).
3703 base_buf_4.edit([(6..10, "BETA")]);
3704 let new_base_str_4: Arc<str> = Arc::from(base_buf_4.text().as_str());
3705 let new_base_snapshot_4 = base_buf_4.snapshot();
3706
3707 let new_hunks_4 = compute_hunks(
3708 Some((new_base_str_4.clone(), Rope::from(new_base_str_4.as_ref()))),
3709 buffer_4.snapshot(),
3710 None,
3711 );
3712
3713 let DiffChanged {
3714 changed_range,
3715 base_text_changed_range,
3716 extended_range: _,
3717 } = compare_hunks(
3718 &new_hunks_4,
3719 &old_hunks_4,
3720 &old_buffer_snapshot_4,
3721 &buffer_4.snapshot(),
3722 &old_base_snapshot_4,
3723 &new_base_snapshot_4,
3724 );
3725
3726 // The old BETA hunk (line 1) is gone and a new DELTA hunk (line 3)
3727 // appeared, so the changed range spans from line 1 through line 4.
3728 let range = changed_range.unwrap();
3729 assert_eq!(
3730 range.to_point(&buffer_4),
3731 Point::new(1, 0)..Point::new(4, 0),
3732 );
3733 let base_range = base_text_changed_range.unwrap();
3734 // The old BETA hunk's base range started at byte 6 ("beta"). After
3735 // the base text edit replacing "beta" with "BETA", anchor_after(6)
3736 // resolves past the insertion to Point(1, 4).
3737 assert_eq!(
3738 base_range.to_point(&new_base_snapshot_4),
3739 Point::new(1, 4)..Point::new(4, 0),
3740 );
3741 }
3742
3743 #[gpui::test(iterations = 100)]
3744 async fn test_patch_for_range_random(cx: &mut TestAppContext, mut rng: StdRng) {
3745 fn gen_line(rng: &mut StdRng) -> String {
3746 if rng.random_bool(0.2) {
3747 "\n".to_owned()
3748 } else {
3749 let c = rng.random_range('A'..='Z');
3750 format!("{c}{c}{c}\n")
3751 }
3752 }
3753
3754 fn gen_text(rng: &mut StdRng, line_count: usize) -> String {
3755 (0..line_count).map(|_| gen_line(rng)).collect()
3756 }
3757
3758 fn gen_edits_from(rng: &mut StdRng, base: &str) -> String {
3759 let mut old_lines: Vec<&str> = base.lines().collect();
3760 let mut result = String::new();
3761
3762 while !old_lines.is_empty() {
3763 let unchanged_count = rng.random_range(0..=old_lines.len());
3764 for _ in 0..unchanged_count {
3765 if old_lines.is_empty() {
3766 break;
3767 }
3768 result.push_str(old_lines.remove(0));
3769 result.push('\n');
3770 }
3771
3772 if old_lines.is_empty() {
3773 break;
3774 }
3775
3776 let deleted_count = rng.random_range(0..=old_lines.len().min(3));
3777 for _ in 0..deleted_count {
3778 if old_lines.is_empty() {
3779 break;
3780 }
3781 old_lines.remove(0);
3782 }
3783
3784 let minimum_added = if deleted_count == 0 { 1 } else { 0 };
3785 let added_count = rng.random_range(minimum_added..=3);
3786 for _ in 0..added_count {
3787 result.push_str(&gen_line(rng));
3788 }
3789 }
3790
3791 result
3792 }
3793
3794 fn random_point_in_text(rng: &mut StdRng, lines: &[&str]) -> Point {
3795 if lines.is_empty() {
3796 return Point::zero();
3797 }
3798 let row = rng.random_range(0..lines.len() as u32);
3799 let line = lines[row as usize];
3800 let col = if line.is_empty() {
3801 0
3802 } else {
3803 rng.random_range(0..=line.len() as u32)
3804 };
3805 Point::new(row, col)
3806 }
3807
3808 fn random_range_in_text(rng: &mut StdRng, lines: &[&str]) -> RangeInclusive<Point> {
3809 let start = random_point_in_text(rng, lines);
3810 let end = random_point_in_text(rng, lines);
3811 if start <= end {
3812 start..=end
3813 } else {
3814 end..=start
3815 }
3816 }
3817
3818 fn points_in_range(range: &RangeInclusive<Point>, lines: &[&str]) -> Vec<Point> {
3819 let mut points = Vec::new();
3820 for row in range.start().row..=range.end().row {
3821 if row as usize >= lines.len() {
3822 points.push(Point::new(row, 0));
3823 continue;
3824 }
3825 let line = lines[row as usize];
3826 let start_col = if row == range.start().row {
3827 range.start().column
3828 } else {
3829 0
3830 };
3831 let end_col = if row == range.end().row {
3832 range.end().column
3833 } else {
3834 line.len() as u32
3835 };
3836 for col in start_col..=end_col {
3837 points.push(Point::new(row, col));
3838 }
3839 }
3840 points
3841 }
3842
3843 let rng = &mut rng;
3844
3845 let line_count = rng.random_range(5..20);
3846 let base_text = gen_text(rng, line_count);
3847 let initial_buffer_text = gen_edits_from(rng, &base_text);
3848
3849 let mut buffer = Buffer::new(
3850 ReplicaId::LOCAL,
3851 BufferId::new(1).unwrap(),
3852 initial_buffer_text.clone(),
3853 );
3854
3855 let diff = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
3856
3857 let edit_count = rng.random_range(1..=5);
3858 for _ in 0..edit_count {
3859 let buffer_text = buffer.text();
3860 if buffer_text.is_empty() {
3861 buffer.edit([(0..0, gen_line(rng))]);
3862 } else {
3863 let lines: Vec<&str> = buffer_text.lines().collect();
3864 let start_row = rng.random_range(0..lines.len());
3865 let end_row = rng.random_range(start_row..=lines.len().min(start_row + 3));
3866
3867 let start_col = if start_row < lines.len() {
3868 rng.random_range(0..=lines[start_row].len())
3869 } else {
3870 0
3871 };
3872 let end_col = if end_row < lines.len() {
3873 rng.random_range(0..=lines[end_row].len())
3874 } else {
3875 0
3876 };
3877
3878 let start_offset = buffer
3879 .point_to_offset(Point::new(start_row as u32, start_col as u32))
3880 .min(buffer.len());
3881 let end_offset = buffer
3882 .point_to_offset(Point::new(end_row as u32, end_col as u32))
3883 .min(buffer.len());
3884
3885 let (start, end) = if start_offset <= end_offset {
3886 (start_offset, end_offset)
3887 } else {
3888 (end_offset, start_offset)
3889 };
3890
3891 let new_text = if rng.random_bool(0.3) {
3892 String::new()
3893 } else {
3894 let line_count = rng.random_range(0..=2);
3895 gen_text(rng, line_count)
3896 };
3897
3898 buffer.edit([(start..end, new_text)]);
3899 }
3900 }
3901
3902 let buffer_snapshot = buffer.snapshot();
3903
3904 let buffer_text = buffer_snapshot.text();
3905 let buffer_lines: Vec<&str> = buffer_text.lines().collect();
3906 let base_lines: Vec<&str> = base_text.lines().collect();
3907
3908 let test_count = 10;
3909 for _ in 0..test_count {
3910 let range = random_range_in_text(rng, &buffer_lines);
3911 let points = points_in_range(&range, &buffer_lines);
3912
3913 let optimized_patch = diff.patch_for_buffer_range(range.clone(), &buffer_snapshot);
3914 let naive_patch = diff.patch_for_buffer_range_naive(&buffer_snapshot);
3915
3916 for point in points {
3917 let optimized_edit = optimized_patch.edit_for_old_position(point);
3918 let naive_edit = naive_patch.edit_for_old_position(point);
3919
3920 assert_eq!(
3921 optimized_edit,
3922 naive_edit,
3923 "patch_for_buffer_range mismatch at point {:?} in range {:?}\nbase_text: {:?}\ninitial_buffer: {:?}\ncurrent_buffer: {:?}",
3924 point,
3925 range,
3926 base_text,
3927 initial_buffer_text,
3928 buffer_snapshot.text()
3929 );
3930 }
3931 }
3932
3933 for _ in 0..test_count {
3934 let range = random_range_in_text(rng, &base_lines);
3935 let points = points_in_range(&range, &base_lines);
3936
3937 let optimized_patch = diff.patch_for_base_text_range(range.clone(), &buffer_snapshot);
3938 let naive_patch = diff.patch_for_base_text_range_naive(&buffer_snapshot);
3939
3940 for point in points {
3941 let optimized_edit = optimized_patch.edit_for_old_position(point);
3942 let naive_edit = naive_patch.edit_for_old_position(point);
3943
3944 assert_eq!(
3945 optimized_edit,
3946 naive_edit,
3947 "patch_for_base_text_range mismatch at point {:?} in range {:?}\nbase_text: {:?}\ninitial_buffer: {:?}\ncurrent_buffer: {:?}",
3948 point,
3949 range,
3950 base_text,
3951 initial_buffer_text,
3952 buffer_snapshot.text()
3953 );
3954 }
3955 }
3956 }
3957}