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
53#[derive(Clone)]
54struct BufferDiffInner<BaseText> {
55 hunks: SumTree<InternalDiffHunk>,
56 pending_hunks: SumTree<PendingHunk>,
57 base_text: BaseText,
58 base_text_exists: bool,
59 buffer_snapshot: text::BufferSnapshot,
60}
61
62impl<BaseText> BufferDiffInner<BaseText> {
63 fn buffer_version(&self) -> &clock::Global {
64 self.buffer_snapshot.version()
65 }
66}
67
68#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
69pub struct DiffHunkStatus {
70 pub kind: DiffHunkStatusKind,
71 pub secondary: DiffHunkSecondaryStatus,
72}
73
74#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
75pub enum DiffHunkStatusKind {
76 Added,
77 Modified,
78 Deleted,
79}
80
81#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
82/// Diff of Working Copy vs Index
83/// aka 'is this hunk staged or not'
84pub enum DiffHunkSecondaryStatus {
85 /// Unstaged
86 HasSecondaryHunk,
87 /// Partially staged
88 OverlapsWithSecondaryHunk,
89 /// Staged
90 NoSecondaryHunk,
91 /// We are unstaging
92 SecondaryHunkAdditionPending,
93 /// We are stagind
94 SecondaryHunkRemovalPending,
95}
96
97/// A diff hunk resolved to rows in the buffer.
98#[derive(Debug, Clone, PartialEq, Eq)]
99pub struct DiffHunk {
100 /// The buffer range as points.
101 pub range: Range<Point>,
102 /// The range in the buffer to which this hunk corresponds.
103 pub buffer_range: Range<Anchor>,
104 /// The range in the buffer's diff base text to which this hunk corresponds.
105 pub diff_base_byte_range: Range<usize>,
106 pub secondary_status: DiffHunkSecondaryStatus,
107 // Anchors representing the word diff locations in the active buffer
108 pub buffer_word_diffs: Vec<Range<Anchor>>,
109 // Offsets relative to the start of the deleted diff that represent word diff locations
110 pub base_word_diffs: Vec<Range<usize>>,
111}
112
113/// We store [`InternalDiffHunk`]s internally so we don't need to store the additional row range.
114#[derive(Debug, Clone, PartialEq, Eq)]
115struct InternalDiffHunk {
116 buffer_range: Range<Anchor>,
117 diff_base_byte_range: Range<usize>,
118 base_word_diffs: Vec<Range<usize>>,
119 buffer_word_diffs: Vec<Range<Anchor>>,
120}
121
122#[derive(Debug, Clone, PartialEq, Eq)]
123struct PendingHunk {
124 buffer_range: Range<Anchor>,
125 diff_base_byte_range: Range<usize>,
126 buffer_version: clock::Global,
127 new_status: DiffHunkSecondaryStatus,
128}
129
130#[derive(Debug, Clone)]
131pub struct DiffHunkSummary {
132 buffer_range: Range<Anchor>,
133 diff_base_byte_range: Range<usize>,
134}
135
136impl sum_tree::Item for InternalDiffHunk {
137 type Summary = DiffHunkSummary;
138
139 fn summary(&self, _cx: &text::BufferSnapshot) -> Self::Summary {
140 DiffHunkSummary {
141 buffer_range: self.buffer_range.clone(),
142 diff_base_byte_range: self.diff_base_byte_range.clone(),
143 }
144 }
145}
146
147impl sum_tree::Item for PendingHunk {
148 type Summary = DiffHunkSummary;
149
150 fn summary(&self, _cx: &text::BufferSnapshot) -> Self::Summary {
151 DiffHunkSummary {
152 buffer_range: self.buffer_range.clone(),
153 diff_base_byte_range: self.diff_base_byte_range.clone(),
154 }
155 }
156}
157
158impl sum_tree::Summary for DiffHunkSummary {
159 type Context<'a> = &'a text::BufferSnapshot;
160
161 fn zero(_cx: Self::Context<'_>) -> Self {
162 DiffHunkSummary {
163 buffer_range: Anchor::MIN..Anchor::MIN,
164 diff_base_byte_range: 0..0,
165 }
166 }
167
168 fn add_summary(&mut self, other: &Self, buffer: Self::Context<'_>) {
169 self.buffer_range.start = *self
170 .buffer_range
171 .start
172 .min(&other.buffer_range.start, buffer);
173 self.buffer_range.end = *self.buffer_range.end.max(&other.buffer_range.end, buffer);
174
175 self.diff_base_byte_range.start = self
176 .diff_base_byte_range
177 .start
178 .min(other.diff_base_byte_range.start);
179 self.diff_base_byte_range.end = self
180 .diff_base_byte_range
181 .end
182 .max(other.diff_base_byte_range.end);
183 }
184}
185
186impl sum_tree::SeekTarget<'_, DiffHunkSummary, DiffHunkSummary> for Anchor {
187 fn cmp(&self, cursor_location: &DiffHunkSummary, buffer: &text::BufferSnapshot) -> Ordering {
188 if self
189 .cmp(&cursor_location.buffer_range.start, buffer)
190 .is_lt()
191 {
192 Ordering::Less
193 } else if self.cmp(&cursor_location.buffer_range.end, buffer).is_gt() {
194 Ordering::Greater
195 } else {
196 Ordering::Equal
197 }
198 }
199}
200
201impl sum_tree::SeekTarget<'_, DiffHunkSummary, DiffHunkSummary> for usize {
202 fn cmp(&self, cursor_location: &DiffHunkSummary, _cx: &text::BufferSnapshot) -> Ordering {
203 if *self < cursor_location.diff_base_byte_range.start {
204 Ordering::Less
205 } else if *self > cursor_location.diff_base_byte_range.end {
206 Ordering::Greater
207 } else {
208 Ordering::Equal
209 }
210 }
211}
212
213impl std::fmt::Debug for BufferDiffInner<language::BufferSnapshot> {
214 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
215 f.debug_struct("BufferDiffSnapshot")
216 .field("hunks", &self.hunks)
217 .field("remote_id", &self.base_text.remote_id())
218 .finish()
219 }
220}
221
222impl BufferDiffSnapshot {
223 #[cfg(test)]
224 fn new_sync(
225 buffer: &text::BufferSnapshot,
226 diff_base: String,
227 cx: &mut gpui::TestAppContext,
228 ) -> BufferDiffSnapshot {
229 let buffer_diff = cx.new(|cx| BufferDiff::new_with_base_text(&diff_base, buffer, cx));
230 buffer_diff.update(cx, |buffer_diff, cx| buffer_diff.snapshot(cx))
231 }
232
233 pub fn is_empty(&self) -> bool {
234 self.inner.hunks.is_empty()
235 }
236
237 pub fn base_text_string(&self) -> Option<String> {
238 self.inner
239 .base_text_exists
240 .then(|| self.inner.base_text.text())
241 }
242
243 pub fn secondary_diff(&self) -> Option<&BufferDiffSnapshot> {
244 self.secondary_diff.as_deref()
245 }
246
247 pub fn buffer_version(&self) -> &clock::Global {
248 self.inner.buffer_version()
249 }
250
251 fn original_buffer_snapshot(&self) -> &text::BufferSnapshot {
252 &self.inner.buffer_snapshot
253 }
254
255 #[ztracing::instrument(skip_all)]
256 pub fn hunks_intersecting_range<'a>(
257 &'a self,
258 range: Range<Anchor>,
259 buffer: &'a text::BufferSnapshot,
260 ) -> impl 'a + Iterator<Item = DiffHunk> {
261 let unstaged_counterpart = self.secondary_diff.as_ref().map(|diff| &diff.inner);
262 self.inner
263 .hunks_intersecting_range(range, buffer, unstaged_counterpart)
264 }
265
266 pub fn hunks_intersecting_range_rev<'a>(
267 &'a self,
268 range: Range<Anchor>,
269 buffer: &'a text::BufferSnapshot,
270 ) -> impl 'a + Iterator<Item = DiffHunk> {
271 let filter = move |summary: &DiffHunkSummary| {
272 let before_start = summary.buffer_range.end.cmp(&range.start, buffer).is_lt();
273 let after_end = summary.buffer_range.start.cmp(&range.end, buffer).is_gt();
274 !before_start && !after_end
275 };
276 self.inner.hunks_intersecting_range_rev_impl(filter, buffer)
277 }
278
279 pub fn hunks_intersecting_base_text_range<'a>(
280 &'a self,
281 range: Range<usize>,
282 main_buffer: &'a text::BufferSnapshot,
283 ) -> impl 'a + Iterator<Item = DiffHunk> {
284 let unstaged_counterpart = self.secondary_diff.as_ref().map(|diff| &diff.inner);
285 let filter = move |summary: &DiffHunkSummary| {
286 let before_start = summary.diff_base_byte_range.end < range.start;
287 let after_end = summary.diff_base_byte_range.start > range.end;
288 !before_start && !after_end
289 };
290 self.inner
291 .hunks_intersecting_range_impl(filter, main_buffer, unstaged_counterpart)
292 }
293
294 pub fn hunks_intersecting_base_text_range_rev<'a>(
295 &'a self,
296 range: Range<usize>,
297 main_buffer: &'a text::BufferSnapshot,
298 ) -> impl 'a + Iterator<Item = DiffHunk> {
299 let filter = move |summary: &DiffHunkSummary| {
300 let before_start = summary.diff_base_byte_range.end.cmp(&range.start).is_lt();
301 let after_end = summary.diff_base_byte_range.start.cmp(&range.end).is_gt();
302 !before_start && !after_end
303 };
304 self.inner
305 .hunks_intersecting_range_rev_impl(filter, main_buffer)
306 }
307
308 pub fn hunks<'a>(
309 &'a self,
310 buffer_snapshot: &'a text::BufferSnapshot,
311 ) -> impl 'a + Iterator<Item = DiffHunk> {
312 self.hunks_intersecting_range(
313 Anchor::min_max_range_for_buffer(buffer_snapshot.remote_id()),
314 buffer_snapshot,
315 )
316 }
317
318 pub fn hunks_in_row_range<'a>(
319 &'a self,
320 range: Range<u32>,
321 buffer: &'a text::BufferSnapshot,
322 ) -> impl 'a + Iterator<Item = DiffHunk> {
323 let start = buffer.anchor_before(Point::new(range.start, 0));
324 let end = buffer.anchor_after(Point::new(range.end, 0));
325 self.hunks_intersecting_range(start..end, buffer)
326 }
327
328 pub fn range_to_hunk_range(
329 &self,
330 range: Range<Anchor>,
331 buffer: &text::BufferSnapshot,
332 ) -> (Option<Range<Anchor>>, Option<Range<usize>>) {
333 let first_hunk = self.hunks_intersecting_range(range.clone(), buffer).next();
334 let last_hunk = self.hunks_intersecting_range_rev(range, buffer).next();
335 let range = first_hunk
336 .as_ref()
337 .zip(last_hunk.as_ref())
338 .map(|(first, last)| first.buffer_range.start..last.buffer_range.end);
339 let base_text_range = first_hunk
340 .zip(last_hunk)
341 .map(|(first, last)| first.diff_base_byte_range.start..last.diff_base_byte_range.end);
342 (range, base_text_range)
343 }
344
345 pub fn base_text(&self) -> &language::BufferSnapshot {
346 &self.inner.base_text
347 }
348
349 /// If this function returns `true`, the base texts are equal. If this
350 /// function returns `false`, they might be equal, but might not. This
351 /// result is used to avoid recalculating diffs in situations where we know
352 /// nothing has changed.
353 pub fn base_texts_definitely_eq(&self, other: &Self) -> bool {
354 if self.inner.base_text_exists != other.inner.base_text_exists {
355 return false;
356 }
357 let left = &self.inner.base_text;
358 let right = &other.inner.base_text;
359 let (old_id, old_version, old_empty) = (left.remote_id(), left.version(), left.is_empty());
360 let (new_id, new_version, new_empty) =
361 (right.remote_id(), right.version(), right.is_empty());
362 (new_id == old_id && new_version == old_version) || (new_empty && old_empty)
363 }
364
365 /// Returns the last hunk whose start is less than or equal to the given position.
366 fn hunk_before_base_text_offset<'a>(
367 &self,
368 target: usize,
369 cursor: &mut sum_tree::Cursor<'a, '_, InternalDiffHunk, DiffHunkSummary>,
370 ) -> Option<&'a InternalDiffHunk> {
371 cursor.seek_forward(&target, Bias::Left);
372 if cursor
373 .item()
374 .is_none_or(|hunk| target < hunk.diff_base_byte_range.start)
375 {
376 cursor.prev();
377 }
378 cursor
379 .item()
380 .filter(|hunk| target >= hunk.diff_base_byte_range.start)
381 }
382
383 fn hunk_before_buffer_anchor<'a>(
384 &self,
385 target: Anchor,
386 cursor: &mut sum_tree::Cursor<'a, '_, InternalDiffHunk, DiffHunkSummary>,
387 buffer: &text::BufferSnapshot,
388 ) -> Option<&'a InternalDiffHunk> {
389 cursor.seek_forward(&target, Bias::Left);
390 if cursor
391 .item()
392 .is_none_or(|hunk| target.cmp(&hunk.buffer_range.start, buffer).is_lt())
393 {
394 cursor.prev();
395 }
396 cursor
397 .item()
398 .filter(|hunk| target.cmp(&hunk.buffer_range.start, buffer).is_ge())
399 }
400
401 /// Returns a patch mapping the provided main buffer snapshot to the base text of this diff.
402 ///
403 /// The returned patch is guaranteed to be accurate for all main buffer points in the provided range,
404 /// but not necessarily for points outside that range.
405 pub fn patch_for_buffer_range<'a>(
406 &'a self,
407 range: RangeInclusive<Point>,
408 buffer: &'a text::BufferSnapshot,
409 ) -> Patch<Point> {
410 if !self.inner.base_text_exists {
411 return Patch::new(vec![Edit {
412 old: Point::zero()..buffer.max_point(),
413 new: Point::zero()..Point::zero(),
414 }]);
415 }
416
417 let mut edits_since_diff = Patch::new(
418 buffer
419 .edits_since::<Point>(&self.inner.buffer_snapshot.version)
420 .collect::<Vec<_>>(),
421 );
422 edits_since_diff.invert();
423
424 let mut start_point = edits_since_diff.old_to_new(*range.start());
425 if let Some(first_edit) = edits_since_diff.edits().first() {
426 start_point = start_point.min(first_edit.new.start);
427 }
428
429 let original_snapshot = self.original_buffer_snapshot();
430 let base_text = self.base_text();
431
432 let mut cursor = self.inner.hunks.cursor(original_snapshot);
433 self.hunk_before_buffer_anchor(
434 original_snapshot.anchor_before(start_point),
435 &mut cursor,
436 original_snapshot,
437 );
438 if cursor.item().is_none() {
439 cursor.next();
440 }
441
442 let mut prefix_edit = cursor.prev_item().map(|prev_hunk| Edit {
443 old: Point::zero()..prev_hunk.buffer_range.end.to_point(original_snapshot),
444 new: Point::zero()..prev_hunk.diff_base_byte_range.end.to_point(base_text),
445 });
446
447 let mut range_end = edits_since_diff.old_to_new(*range.end());
448 if let Some(last_edit) = edits_since_diff.edits().last() {
449 range_end = range_end.max(last_edit.new.end);
450 }
451 let range_end = original_snapshot.anchor_before(range_end);
452
453 let hunk_iter = std::iter::from_fn(move || {
454 if let Some(edit) = prefix_edit.take() {
455 return Some(edit);
456 }
457 let hunk = cursor.item()?;
458 if hunk
459 .buffer_range
460 .start
461 .cmp(&range_end, original_snapshot)
462 .is_gt()
463 {
464 return None;
465 }
466 let edit = Edit {
467 old: hunk.buffer_range.to_point(original_snapshot),
468 new: hunk.diff_base_byte_range.to_point(base_text),
469 };
470 cursor.next();
471 Some(edit)
472 });
473
474 edits_since_diff.compose(hunk_iter)
475 }
476
477 #[cfg(test)]
478 pub(crate) fn patch_for_buffer_range_naive<'a>(
479 &'a self,
480 buffer: &'a text::BufferSnapshot,
481 ) -> Patch<Point> {
482 let original_snapshot = self.original_buffer_snapshot();
483
484 let edits_since: Vec<Edit<Point>> = buffer
485 .edits_since::<Point>(original_snapshot.version())
486 .collect();
487 let mut inverted_edits_since = Patch::new(edits_since);
488 inverted_edits_since.invert();
489
490 inverted_edits_since.compose(
491 self.inner
492 .hunks
493 .iter()
494 .map(|hunk| {
495 let old_start = hunk.buffer_range.start.to_point(original_snapshot);
496 let old_end = hunk.buffer_range.end.to_point(original_snapshot);
497 let new_start = self
498 .base_text()
499 .offset_to_point(hunk.diff_base_byte_range.start);
500 let new_end = self
501 .base_text()
502 .offset_to_point(hunk.diff_base_byte_range.end);
503 Edit {
504 old: old_start..old_end,
505 new: new_start..new_end,
506 }
507 })
508 .chain(
509 if !self.inner.base_text_exists && self.inner.hunks.is_empty() {
510 Some(Edit {
511 old: Point::zero()..original_snapshot.max_point(),
512 new: Point::zero()..Point::zero(),
513 })
514 } else {
515 None
516 },
517 ),
518 )
519 }
520
521 /// Returns a patch mapping the base text of this diff to the provided main buffer snapshot.
522 ///
523 /// The returned patch is guaranteed to be accurate for all base text points in the provided range,
524 /// but not necessarily for points outside that range.
525 pub fn patch_for_base_text_range<'a>(
526 &'a self,
527 range: RangeInclusive<Point>,
528 buffer: &'a text::BufferSnapshot,
529 ) -> Patch<Point> {
530 if !self.inner.base_text_exists {
531 return Patch::new(vec![Edit {
532 old: Point::zero()..Point::zero(),
533 new: Point::zero()..buffer.max_point(),
534 }]);
535 }
536
537 let edits_since_diff = buffer
538 .edits_since::<Point>(&self.inner.buffer_snapshot.version)
539 .collect::<Vec<_>>();
540
541 let mut hunk_patch = Vec::new();
542 let mut cursor = self.inner.hunks.cursor(self.original_buffer_snapshot());
543 let hunk_before = self
544 .hunk_before_base_text_offset(range.start().to_offset(self.base_text()), &mut cursor);
545
546 if let Some(hunk) = hunk_before
547 && let Some(first_edit) = edits_since_diff.first()
548 && hunk
549 .buffer_range
550 .start
551 .to_point(self.original_buffer_snapshot())
552 > first_edit.old.start
553 {
554 cursor.reset();
555 self.hunk_before_buffer_anchor(
556 self.original_buffer_snapshot()
557 .anchor_before(first_edit.old.start),
558 &mut cursor,
559 self.original_buffer_snapshot(),
560 );
561 }
562 if cursor.item().is_none() {
563 cursor.next();
564 }
565 if let Some(prev_hunk) = cursor.prev_item() {
566 hunk_patch.push(Edit {
567 old: Point::zero()
568 ..prev_hunk
569 .diff_base_byte_range
570 .end
571 .to_point(self.base_text()),
572 new: Point::zero()
573 ..prev_hunk
574 .buffer_range
575 .end
576 .to_point(self.original_buffer_snapshot()),
577 })
578 }
579 let range_end = range.end().to_offset(self.base_text());
580 while let Some(hunk) = cursor.item()
581 && (hunk.diff_base_byte_range.start <= range_end
582 || edits_since_diff.last().is_some_and(|last_edit| {
583 hunk.buffer_range
584 .start
585 .to_point(self.original_buffer_snapshot())
586 <= last_edit.old.end
587 }))
588 {
589 hunk_patch.push(Edit {
590 old: hunk.diff_base_byte_range.to_point(self.base_text()),
591 new: hunk.buffer_range.to_point(self.original_buffer_snapshot()),
592 });
593 cursor.next();
594 }
595
596 Patch::new(hunk_patch).compose(edits_since_diff)
597 }
598
599 #[cfg(test)]
600 pub(crate) fn patch_for_base_text_range_naive<'a>(
601 &'a self,
602 buffer: &'a text::BufferSnapshot,
603 ) -> Patch<Point> {
604 let original_snapshot = self.original_buffer_snapshot();
605
606 let mut hunk_edits: Vec<Edit<Point>> = Vec::new();
607 for hunk in self.inner.hunks.iter() {
608 let old_start = self
609 .base_text()
610 .offset_to_point(hunk.diff_base_byte_range.start);
611 let old_end = self
612 .base_text()
613 .offset_to_point(hunk.diff_base_byte_range.end);
614 let new_start = hunk.buffer_range.start.to_point(original_snapshot);
615 let new_end = hunk.buffer_range.end.to_point(original_snapshot);
616 hunk_edits.push(Edit {
617 old: old_start..old_end,
618 new: new_start..new_end,
619 });
620 }
621 if !self.inner.base_text_exists && hunk_edits.is_empty() {
622 hunk_edits.push(Edit {
623 old: Point::zero()..Point::zero(),
624 new: Point::zero()..original_snapshot.max_point(),
625 })
626 }
627 let hunk_patch = Patch::new(hunk_edits);
628
629 hunk_patch.compose(buffer.edits_since::<Point>(original_snapshot.version()))
630 }
631
632 pub fn buffer_point_to_base_text_range(
633 &self,
634 point: Point,
635 buffer: &text::BufferSnapshot,
636 ) -> Range<Point> {
637 let patch = self.patch_for_buffer_range(point..=point, buffer);
638 let edit = patch.edit_for_old_position(point);
639 edit.new
640 }
641
642 pub fn base_text_point_to_buffer_range(
643 &self,
644 point: Point,
645 buffer: &text::BufferSnapshot,
646 ) -> Range<Point> {
647 let patch = self.patch_for_base_text_range(point..=point, buffer);
648 let edit = patch.edit_for_old_position(point);
649 edit.new
650 }
651
652 pub fn buffer_point_to_base_text_point(
653 &self,
654 point: Point,
655 buffer: &text::BufferSnapshot,
656 ) -> Point {
657 let patch = self.patch_for_buffer_range(point..=point, buffer);
658 let edit = patch.edit_for_old_position(point);
659 if point == edit.old.end {
660 edit.new.end
661 } else {
662 edit.new.start
663 }
664 }
665
666 pub fn base_text_point_to_buffer_point(
667 &self,
668 point: Point,
669 buffer: &text::BufferSnapshot,
670 ) -> Point {
671 let patch = self.patch_for_base_text_range(point..=point, buffer);
672 let edit = patch.edit_for_old_position(point);
673 if point == edit.old.end {
674 edit.new.end
675 } else {
676 edit.new.start
677 }
678 }
679}
680
681impl BufferDiffInner<Entity<language::Buffer>> {
682 /// Returns the new index text and new pending hunks.
683 fn stage_or_unstage_hunks_impl(
684 &mut self,
685 unstaged_diff: &Self,
686 stage: bool,
687 hunks: &[DiffHunk],
688 buffer: &text::BufferSnapshot,
689 file_exists: bool,
690 cx: &mut Context<BufferDiff>,
691 ) -> Option<Rope> {
692 let head_text = self
693 .base_text_exists
694 .then(|| self.base_text.read(cx).as_rope().clone());
695 let index_text = unstaged_diff
696 .base_text_exists
697 .then(|| unstaged_diff.base_text.read(cx).as_rope().clone());
698
699 // If the file doesn't exist in either HEAD or the index, then the
700 // entire file must be either created or deleted in the index.
701 let (index_text, head_text) = match (index_text, head_text) {
702 (Some(index_text), Some(head_text)) if file_exists || !stage => (index_text, head_text),
703 (index_text, head_text) => {
704 let (new_index_text, new_status) = if stage {
705 log::debug!("stage all");
706 (
707 file_exists.then(|| buffer.as_rope().clone()),
708 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending,
709 )
710 } else {
711 log::debug!("unstage all");
712 (
713 head_text,
714 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending,
715 )
716 };
717
718 let hunk = PendingHunk {
719 buffer_range: Anchor::min_max_range_for_buffer(buffer.remote_id()),
720 diff_base_byte_range: 0..index_text.map_or(0, |rope| rope.len()),
721 buffer_version: buffer.version().clone(),
722 new_status,
723 };
724 self.pending_hunks = SumTree::from_item(hunk, buffer);
725 return new_index_text;
726 }
727 };
728
729 let mut pending_hunks = SumTree::new(buffer);
730 let mut old_pending_hunks = self.pending_hunks.cursor::<DiffHunkSummary>(buffer);
731
732 // first, merge new hunks into pending_hunks
733 for DiffHunk {
734 buffer_range,
735 diff_base_byte_range,
736 secondary_status,
737 ..
738 } in hunks.iter().cloned()
739 {
740 let preceding_pending_hunks = old_pending_hunks.slice(&buffer_range.start, Bias::Left);
741 pending_hunks.append(preceding_pending_hunks, buffer);
742
743 // Skip all overlapping or adjacent old pending hunks
744 while old_pending_hunks.item().is_some_and(|old_hunk| {
745 old_hunk
746 .buffer_range
747 .start
748 .cmp(&buffer_range.end, buffer)
749 .is_le()
750 }) {
751 old_pending_hunks.next();
752 }
753
754 if (stage && secondary_status == DiffHunkSecondaryStatus::NoSecondaryHunk)
755 || (!stage && secondary_status == DiffHunkSecondaryStatus::HasSecondaryHunk)
756 {
757 continue;
758 }
759
760 pending_hunks.push(
761 PendingHunk {
762 buffer_range,
763 diff_base_byte_range,
764 buffer_version: buffer.version().clone(),
765 new_status: if stage {
766 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
767 } else {
768 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
769 },
770 },
771 buffer,
772 );
773 }
774 // append the remainder
775 pending_hunks.append(old_pending_hunks.suffix(), buffer);
776
777 let mut unstaged_hunk_cursor = unstaged_diff.hunks.cursor::<DiffHunkSummary>(buffer);
778 unstaged_hunk_cursor.next();
779
780 // then, iterate over all pending hunks (both new ones and the existing ones) and compute the edits
781 let mut prev_unstaged_hunk_buffer_end = 0;
782 let mut prev_unstaged_hunk_base_text_end = 0;
783 let mut edits = Vec::<(Range<usize>, String)>::new();
784 let mut pending_hunks_iter = pending_hunks.iter().cloned().peekable();
785 while let Some(PendingHunk {
786 buffer_range,
787 diff_base_byte_range,
788 new_status,
789 ..
790 }) = pending_hunks_iter.next()
791 {
792 // Advance unstaged_hunk_cursor to skip unstaged hunks before current hunk
793 let skipped_unstaged = unstaged_hunk_cursor.slice(&buffer_range.start, Bias::Left);
794
795 if let Some(unstaged_hunk) = skipped_unstaged.last() {
796 prev_unstaged_hunk_base_text_end = unstaged_hunk.diff_base_byte_range.end;
797 prev_unstaged_hunk_buffer_end = unstaged_hunk.buffer_range.end.to_offset(buffer);
798 }
799
800 // Find where this hunk is in the index if it doesn't overlap
801 let mut buffer_offset_range = buffer_range.to_offset(buffer);
802 let start_overshoot = buffer_offset_range.start - prev_unstaged_hunk_buffer_end;
803 let mut index_start = prev_unstaged_hunk_base_text_end + start_overshoot;
804
805 loop {
806 // Merge this hunk with any overlapping unstaged hunks.
807 if let Some(unstaged_hunk) = unstaged_hunk_cursor.item() {
808 let unstaged_hunk_offset_range = unstaged_hunk.buffer_range.to_offset(buffer);
809 if unstaged_hunk_offset_range.start <= buffer_offset_range.end {
810 prev_unstaged_hunk_base_text_end = unstaged_hunk.diff_base_byte_range.end;
811 prev_unstaged_hunk_buffer_end = unstaged_hunk_offset_range.end;
812
813 index_start = index_start.min(unstaged_hunk.diff_base_byte_range.start);
814 buffer_offset_range.start = buffer_offset_range
815 .start
816 .min(unstaged_hunk_offset_range.start);
817 buffer_offset_range.end =
818 buffer_offset_range.end.max(unstaged_hunk_offset_range.end);
819
820 unstaged_hunk_cursor.next();
821 continue;
822 }
823 }
824
825 // If any unstaged hunks were merged, then subsequent pending hunks may
826 // now overlap this hunk. Merge them.
827 if let Some(next_pending_hunk) = pending_hunks_iter.peek() {
828 let next_pending_hunk_offset_range =
829 next_pending_hunk.buffer_range.to_offset(buffer);
830 if next_pending_hunk_offset_range.start <= buffer_offset_range.end {
831 buffer_offset_range.end = buffer_offset_range
832 .end
833 .max(next_pending_hunk_offset_range.end);
834 pending_hunks_iter.next();
835 continue;
836 }
837 }
838
839 break;
840 }
841
842 let end_overshoot = buffer_offset_range
843 .end
844 .saturating_sub(prev_unstaged_hunk_buffer_end);
845 let index_end = prev_unstaged_hunk_base_text_end + end_overshoot;
846
847 // Clamp to the index text bounds. The overshoot mapping assumes that
848 // text between unstaged hunks is identical in the buffer and index.
849 // When the buffer has been edited since the diff was computed, anchor
850 // positions shift while diff_base_byte_range values don't, which can
851 // cause index_end to exceed index_text.len().
852 // See `test_stage_all_with_stale_buffer` which would hit an assert
853 // without these min calls
854 let index_end = index_end.min(index_text.len());
855 let index_start = index_start.min(index_end);
856 let index_byte_range = index_start..index_end;
857
858 let replacement_text = match new_status {
859 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending => {
860 log::debug!("staging hunk {:?}", buffer_offset_range);
861 buffer
862 .text_for_range(buffer_offset_range)
863 .collect::<String>()
864 }
865 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending => {
866 log::debug!("unstaging hunk {:?}", buffer_offset_range);
867 head_text
868 .chunks_in_range(diff_base_byte_range.clone())
869 .collect::<String>()
870 }
871 _ => {
872 debug_assert!(false);
873 continue;
874 }
875 };
876
877 edits.push((index_byte_range, replacement_text));
878 }
879 drop(pending_hunks_iter);
880 drop(old_pending_hunks);
881 self.pending_hunks = pending_hunks;
882
883 #[cfg(debug_assertions)] // invariants: non-overlapping and sorted
884 {
885 for window in edits.windows(2) {
886 let (range_a, range_b) = (&window[0].0, &window[1].0);
887 debug_assert!(range_a.end < range_b.start);
888 }
889 }
890
891 let mut new_index_text = Rope::new();
892 let mut index_cursor = index_text.cursor(0);
893
894 for (old_range, replacement_text) in edits {
895 new_index_text.append(index_cursor.slice(old_range.start));
896 index_cursor.seek_forward(old_range.end);
897 new_index_text.push(&replacement_text);
898 }
899 new_index_text.append(index_cursor.suffix());
900 Some(new_index_text)
901 }
902}
903
904impl BufferDiffInner<language::BufferSnapshot> {
905 fn hunks_intersecting_range<'a>(
906 &'a self,
907 range: Range<Anchor>,
908 buffer: &'a text::BufferSnapshot,
909 secondary: Option<&'a Self>,
910 ) -> impl 'a + Iterator<Item = DiffHunk> {
911 let range = range.to_offset(buffer);
912 let filter = move |summary: &DiffHunkSummary| {
913 let summary_range = summary.buffer_range.to_offset(buffer);
914 let before_start = summary_range.end < range.start;
915 let after_end = summary_range.start > range.end;
916 !before_start && !after_end
917 };
918 self.hunks_intersecting_range_impl(filter, buffer, secondary)
919 }
920
921 fn hunks_intersecting_range_impl<'a>(
922 &'a self,
923 filter: impl 'a + Fn(&DiffHunkSummary) -> bool,
924 buffer: &'a text::BufferSnapshot,
925 secondary: Option<&'a Self>,
926 ) -> impl 'a + Iterator<Item = DiffHunk> {
927 let anchor_iter = self
928 .hunks
929 .filter::<_, DiffHunkSummary>(buffer, filter)
930 .flat_map(move |hunk| {
931 [
932 (
933 &hunk.buffer_range.start,
934 (
935 hunk.buffer_range.start,
936 hunk.diff_base_byte_range.start,
937 hunk,
938 ),
939 ),
940 (
941 &hunk.buffer_range.end,
942 (hunk.buffer_range.end, hunk.diff_base_byte_range.end, hunk),
943 ),
944 ]
945 });
946
947 let mut pending_hunks_cursor = self.pending_hunks.cursor::<DiffHunkSummary>(buffer);
948 pending_hunks_cursor.next();
949
950 let mut secondary_cursor = None;
951 if let Some(secondary) = secondary.as_ref() {
952 let mut cursor = secondary.hunks.cursor::<DiffHunkSummary>(buffer);
953 cursor.next();
954 secondary_cursor = Some(cursor);
955 }
956
957 let max_point = buffer.max_point();
958 let mut summaries = buffer.summaries_for_anchors_with_payload::<Point, _, _>(anchor_iter);
959 iter::from_fn(move || {
960 loop {
961 let (start_point, (start_anchor, start_base, hunk)) = summaries.next()?;
962 let (mut end_point, (mut end_anchor, end_base, _)) = summaries.next()?;
963
964 let base_word_diffs = hunk.base_word_diffs.clone();
965 let buffer_word_diffs = hunk.buffer_word_diffs.clone();
966
967 if !start_anchor.is_valid(buffer) {
968 continue;
969 }
970
971 if end_point.column > 0 && end_point < max_point {
972 end_point.row += 1;
973 end_point.column = 0;
974 end_anchor = buffer.anchor_before(end_point);
975 }
976
977 let mut secondary_status = DiffHunkSecondaryStatus::NoSecondaryHunk;
978
979 let mut has_pending = false;
980 if start_anchor
981 .cmp(&pending_hunks_cursor.start().buffer_range.start, buffer)
982 .is_gt()
983 {
984 pending_hunks_cursor.seek_forward(&start_anchor, Bias::Left);
985 }
986
987 if let Some(pending_hunk) = pending_hunks_cursor.item() {
988 let mut pending_range = pending_hunk.buffer_range.to_point(buffer);
989 if pending_range.end.column > 0 {
990 pending_range.end.row += 1;
991 pending_range.end.column = 0;
992 }
993
994 if pending_range == (start_point..end_point)
995 && !buffer.has_edits_since_in_range(
996 &pending_hunk.buffer_version,
997 start_anchor..end_anchor,
998 )
999 {
1000 has_pending = true;
1001 secondary_status = pending_hunk.new_status;
1002 }
1003 }
1004
1005 if let (Some(secondary_cursor), false) = (secondary_cursor.as_mut(), has_pending) {
1006 if start_anchor
1007 .cmp(&secondary_cursor.start().buffer_range.start, buffer)
1008 .is_gt()
1009 {
1010 secondary_cursor.seek_forward(&start_anchor, Bias::Left);
1011 }
1012
1013 if let Some(secondary_hunk) = secondary_cursor.item() {
1014 let mut secondary_range = secondary_hunk.buffer_range.to_point(buffer);
1015 if secondary_range.end.column > 0 {
1016 secondary_range.end.row += 1;
1017 secondary_range.end.column = 0;
1018 }
1019 if secondary_range.is_empty()
1020 && secondary_hunk.diff_base_byte_range.is_empty()
1021 {
1022 // ignore
1023 } else if secondary_range == (start_point..end_point) {
1024 secondary_status = DiffHunkSecondaryStatus::HasSecondaryHunk;
1025 } else if secondary_range.start <= end_point {
1026 secondary_status = DiffHunkSecondaryStatus::OverlapsWithSecondaryHunk;
1027 }
1028 }
1029 }
1030
1031 return Some(DiffHunk {
1032 range: start_point..end_point,
1033 diff_base_byte_range: start_base..end_base,
1034 buffer_range: start_anchor..end_anchor,
1035 base_word_diffs,
1036 buffer_word_diffs,
1037 secondary_status,
1038 });
1039 }
1040 })
1041 }
1042
1043 fn hunks_intersecting_range_rev_impl<'a>(
1044 &'a self,
1045 filter: impl 'a + Fn(&DiffHunkSummary) -> bool,
1046 buffer: &'a text::BufferSnapshot,
1047 ) -> impl 'a + Iterator<Item = DiffHunk> {
1048 let mut cursor = self.hunks.filter::<_, DiffHunkSummary>(buffer, filter);
1049
1050 iter::from_fn(move || {
1051 cursor.prev();
1052
1053 let hunk = cursor.item()?;
1054 let range = hunk.buffer_range.to_point(buffer);
1055
1056 Some(DiffHunk {
1057 range,
1058 diff_base_byte_range: hunk.diff_base_byte_range.clone(),
1059 buffer_range: hunk.buffer_range.clone(),
1060 // The secondary status is not used by callers of this method.
1061 secondary_status: DiffHunkSecondaryStatus::NoSecondaryHunk,
1062 base_word_diffs: hunk.base_word_diffs.clone(),
1063 buffer_word_diffs: hunk.buffer_word_diffs.clone(),
1064 })
1065 })
1066 }
1067}
1068
1069fn build_diff_options(
1070 file: Option<&Arc<dyn File>>,
1071 language: Option<LanguageName>,
1072 language_scope: Option<language::LanguageScope>,
1073 cx: &App,
1074) -> Option<DiffOptions> {
1075 #[cfg(any(test, feature = "test-support"))]
1076 {
1077 if !cx.has_global::<settings::SettingsStore>() {
1078 return Some(DiffOptions {
1079 language_scope,
1080 max_word_diff_line_count: MAX_WORD_DIFF_LINE_COUNT,
1081 ..Default::default()
1082 });
1083 }
1084 }
1085
1086 language_settings(language, file, cx)
1087 .word_diff_enabled
1088 .then_some(DiffOptions {
1089 language_scope,
1090 max_word_diff_line_count: MAX_WORD_DIFF_LINE_COUNT,
1091 ..Default::default()
1092 })
1093}
1094
1095fn compute_hunks(
1096 diff_base: Option<(Arc<str>, Rope)>,
1097 buffer: &text::BufferSnapshot,
1098 diff_options: Option<DiffOptions>,
1099) -> SumTree<InternalDiffHunk> {
1100 let mut tree = SumTree::new(buffer);
1101
1102 if let Some((diff_base, diff_base_rope)) = diff_base {
1103 let buffer_text = buffer.as_rope().to_string();
1104
1105 let mut options = GitOptions::default();
1106 options.context_lines(0);
1107 let patch = GitPatch::from_buffers(
1108 diff_base.as_bytes(),
1109 None,
1110 buffer_text.as_bytes(),
1111 None,
1112 Some(&mut options),
1113 )
1114 .log_err();
1115
1116 // A common case in Zed is that the empty buffer is represented as just a newline,
1117 // but if we just compute a naive diff you get a "preserved" line in the middle,
1118 // which is a bit odd.
1119 if buffer_text == "\n" && diff_base.ends_with("\n") && diff_base.len() > 1 {
1120 tree.push(
1121 InternalDiffHunk {
1122 buffer_range: buffer.anchor_before(0)..buffer.anchor_before(0),
1123 diff_base_byte_range: 0..diff_base.len() - 1,
1124 base_word_diffs: Vec::default(),
1125 buffer_word_diffs: Vec::default(),
1126 },
1127 buffer,
1128 );
1129 return tree;
1130 }
1131
1132 if let Some(patch) = patch {
1133 let mut divergence = 0;
1134 for hunk_index in 0..patch.num_hunks() {
1135 let hunk = process_patch_hunk(
1136 &patch,
1137 hunk_index,
1138 &diff_base_rope,
1139 buffer,
1140 &mut divergence,
1141 diff_options.as_ref(),
1142 );
1143 tree.push(hunk, buffer);
1144 }
1145 }
1146 } else {
1147 tree.push(
1148 InternalDiffHunk {
1149 buffer_range: Anchor::min_max_range_for_buffer(buffer.remote_id()),
1150 diff_base_byte_range: 0..0,
1151 base_word_diffs: Vec::default(),
1152 buffer_word_diffs: Vec::default(),
1153 },
1154 buffer,
1155 );
1156 }
1157
1158 tree
1159}
1160
1161fn compare_hunks(
1162 new_hunks: &SumTree<InternalDiffHunk>,
1163 old_hunks: &SumTree<InternalDiffHunk>,
1164 old_snapshot: &text::BufferSnapshot,
1165 new_snapshot: &text::BufferSnapshot,
1166 old_base_text: &text::BufferSnapshot,
1167 new_base_text: &text::BufferSnapshot,
1168) -> DiffChanged {
1169 let mut new_cursor = new_hunks.cursor::<()>(new_snapshot);
1170 let mut old_cursor = old_hunks.cursor::<()>(new_snapshot);
1171 old_cursor.next();
1172 new_cursor.next();
1173 let mut start = None;
1174 let mut end = None;
1175 let mut base_text_start: Option<Anchor> = None;
1176 let mut base_text_end: Option<Anchor> = None;
1177
1178 let mut last_unchanged_new_hunk_end: Option<text::Anchor> = None;
1179 let mut has_changes = false;
1180 let mut extended_end_candidate: Option<text::Anchor> = None;
1181
1182 loop {
1183 match (new_cursor.item(), old_cursor.item()) {
1184 (Some(new_hunk), Some(old_hunk)) => {
1185 match new_hunk
1186 .buffer_range
1187 .start
1188 .cmp(&old_hunk.buffer_range.start, new_snapshot)
1189 {
1190 Ordering::Less => {
1191 has_changes = true;
1192 extended_end_candidate = None;
1193 start.get_or_insert(new_hunk.buffer_range.start);
1194 base_text_start.get_or_insert(
1195 new_base_text.anchor_before(new_hunk.diff_base_byte_range.start),
1196 );
1197 end.replace(new_hunk.buffer_range.end);
1198 let new_diff_range_end =
1199 new_base_text.anchor_after(new_hunk.diff_base_byte_range.end);
1200 if base_text_end.is_none_or(|base_text_end| {
1201 new_diff_range_end
1202 .cmp(&base_text_end, &new_base_text)
1203 .is_gt()
1204 }) {
1205 base_text_end = Some(new_diff_range_end)
1206 }
1207 new_cursor.next();
1208 }
1209 Ordering::Equal => {
1210 if new_hunk != old_hunk {
1211 has_changes = true;
1212 extended_end_candidate = None;
1213 start.get_or_insert(new_hunk.buffer_range.start);
1214 base_text_start.get_or_insert(
1215 new_base_text.anchor_before(new_hunk.diff_base_byte_range.start),
1216 );
1217 if old_hunk
1218 .buffer_range
1219 .end
1220 .cmp(&new_hunk.buffer_range.end, new_snapshot)
1221 .is_ge()
1222 {
1223 end.replace(old_hunk.buffer_range.end);
1224 } else {
1225 end.replace(new_hunk.buffer_range.end);
1226 }
1227
1228 let old_hunk_diff_base_range_end =
1229 old_base_text.anchor_after(old_hunk.diff_base_byte_range.end);
1230 let new_hunk_diff_base_range_end =
1231 new_base_text.anchor_after(new_hunk.diff_base_byte_range.end);
1232
1233 base_text_end.replace(
1234 *old_hunk_diff_base_range_end
1235 .max(&new_hunk_diff_base_range_end, new_base_text),
1236 );
1237 } else {
1238 if !has_changes {
1239 last_unchanged_new_hunk_end = Some(new_hunk.buffer_range.end);
1240 } else if extended_end_candidate.is_none() {
1241 extended_end_candidate = Some(new_hunk.buffer_range.start);
1242 }
1243 }
1244
1245 new_cursor.next();
1246 old_cursor.next();
1247 }
1248 Ordering::Greater => {
1249 has_changes = true;
1250 extended_end_candidate = None;
1251 start.get_or_insert(old_hunk.buffer_range.start);
1252 base_text_start.get_or_insert(
1253 old_base_text.anchor_after(old_hunk.diff_base_byte_range.start),
1254 );
1255 end.replace(old_hunk.buffer_range.end);
1256 let old_diff_range_end =
1257 old_base_text.anchor_after(old_hunk.diff_base_byte_range.end);
1258 if base_text_end.is_none_or(|base_text_end| {
1259 old_diff_range_end
1260 .cmp(&base_text_end, new_base_text)
1261 .is_gt()
1262 }) {
1263 base_text_end = Some(old_diff_range_end)
1264 }
1265 old_cursor.next();
1266 }
1267 }
1268 }
1269 (Some(new_hunk), None) => {
1270 has_changes = true;
1271 extended_end_candidate = None;
1272 start.get_or_insert(new_hunk.buffer_range.start);
1273 base_text_start
1274 .get_or_insert(new_base_text.anchor_after(new_hunk.diff_base_byte_range.start));
1275 if end.is_none_or(|end| end.cmp(&new_hunk.buffer_range.end, &new_snapshot).is_le())
1276 {
1277 end.replace(new_hunk.buffer_range.end);
1278 }
1279 let new_base_text_end =
1280 new_base_text.anchor_after(new_hunk.diff_base_byte_range.end);
1281 if base_text_end.is_none_or(|base_text_end| {
1282 new_base_text_end.cmp(&base_text_end, new_base_text).is_gt()
1283 }) {
1284 base_text_end = Some(new_base_text_end)
1285 }
1286 new_cursor.next();
1287 }
1288 (None, Some(old_hunk)) => {
1289 has_changes = true;
1290 extended_end_candidate = None;
1291 start.get_or_insert(old_hunk.buffer_range.start);
1292 base_text_start
1293 .get_or_insert(old_base_text.anchor_after(old_hunk.diff_base_byte_range.start));
1294 if end.is_none_or(|end| end.cmp(&old_hunk.buffer_range.end, &new_snapshot).is_le())
1295 {
1296 end.replace(old_hunk.buffer_range.end);
1297 }
1298 let old_base_text_end =
1299 old_base_text.anchor_after(old_hunk.diff_base_byte_range.end);
1300 if base_text_end.is_none_or(|base_text_end| {
1301 old_base_text_end.cmp(&base_text_end, new_base_text).is_gt()
1302 }) {
1303 base_text_end = Some(old_base_text_end);
1304 }
1305 old_cursor.next();
1306 }
1307 (None, None) => break,
1308 }
1309 }
1310
1311 let changed_range = start.zip(end).map(|(start, end)| start..end);
1312 let base_text_changed_range = base_text_start
1313 .zip(base_text_end)
1314 .map(|(start, end)| (start..end).to_offset(new_base_text));
1315
1316 let extended_range = if has_changes && let Some(changed_range) = changed_range.clone() {
1317 let extended_start = *last_unchanged_new_hunk_end
1318 .unwrap_or(text::Anchor::min_for_buffer(new_snapshot.remote_id()))
1319 .min(&changed_range.start, new_snapshot);
1320 let extended_start = new_snapshot
1321 .anchored_edits_since_in_range::<usize>(
1322 &old_snapshot.version(),
1323 extended_start..changed_range.start,
1324 )
1325 .map(|(_, anchors)| anchors.start)
1326 .min_by(|a, b| a.cmp(b, new_snapshot))
1327 .unwrap_or(changed_range.start);
1328
1329 let extended_end = *extended_end_candidate
1330 .unwrap_or(text::Anchor::max_for_buffer(new_snapshot.remote_id()))
1331 .max(&changed_range.end, new_snapshot);
1332 let extended_end = new_snapshot
1333 .anchored_edits_since_in_range::<usize>(
1334 &old_snapshot.version(),
1335 changed_range.end..extended_end,
1336 )
1337 .map(|(_, anchors)| anchors.end)
1338 .max_by(|a, b| a.cmp(b, new_snapshot))
1339 .unwrap_or(changed_range.end);
1340
1341 Some(extended_start..extended_end)
1342 } else {
1343 None
1344 };
1345
1346 DiffChanged {
1347 changed_range,
1348 base_text_changed_range,
1349 extended_range,
1350 }
1351}
1352
1353fn process_patch_hunk(
1354 patch: &GitPatch<'_>,
1355 hunk_index: usize,
1356 diff_base: &Rope,
1357 buffer: &text::BufferSnapshot,
1358 buffer_row_divergence: &mut i64,
1359 diff_options: Option<&DiffOptions>,
1360) -> InternalDiffHunk {
1361 let line_item_count = patch.num_lines_in_hunk(hunk_index).unwrap();
1362 assert!(line_item_count > 0);
1363
1364 let mut first_deletion_buffer_row: Option<u32> = None;
1365 let mut buffer_row_range: Option<Range<u32>> = None;
1366 let mut diff_base_byte_range: Option<Range<usize>> = None;
1367 let mut first_addition_old_row: Option<u32> = None;
1368
1369 for line_index in 0..line_item_count {
1370 let line = patch.line_in_hunk(hunk_index, line_index).unwrap();
1371 let kind = line.origin_value();
1372 let content_offset = line.content_offset() as isize;
1373 let content_len = line.content().len() as isize;
1374 match kind {
1375 GitDiffLineType::Addition => {
1376 if first_addition_old_row.is_none() {
1377 first_addition_old_row = Some(
1378 (line.new_lineno().unwrap() as i64 - *buffer_row_divergence - 1) as u32,
1379 );
1380 }
1381 *buffer_row_divergence += 1;
1382 let row = line.new_lineno().unwrap().saturating_sub(1);
1383
1384 match &mut buffer_row_range {
1385 Some(Range { end, .. }) => *end = row + 1,
1386 None => buffer_row_range = Some(row..row + 1),
1387 }
1388 }
1389 GitDiffLineType::Deletion => {
1390 let end = content_offset + content_len;
1391
1392 match &mut diff_base_byte_range {
1393 Some(head_byte_range) => head_byte_range.end = end as usize,
1394 None => diff_base_byte_range = Some(content_offset as usize..end as usize),
1395 }
1396
1397 if first_deletion_buffer_row.is_none() {
1398 let old_row = line.old_lineno().unwrap().saturating_sub(1);
1399 let row = old_row as i64 + *buffer_row_divergence;
1400 first_deletion_buffer_row = Some(row as u32);
1401 }
1402
1403 *buffer_row_divergence -= 1;
1404 }
1405 _ => {}
1406 }
1407 }
1408
1409 let buffer_row_range = buffer_row_range.unwrap_or_else(|| {
1410 // Pure deletion hunk without addition.
1411 let row = first_deletion_buffer_row.unwrap();
1412 row..row
1413 });
1414 let diff_base_byte_range = diff_base_byte_range.unwrap_or_else(|| {
1415 // Pure addition hunk without deletion.
1416 let row = first_addition_old_row.unwrap();
1417 let offset = diff_base.point_to_offset(Point::new(row, 0));
1418 offset..offset
1419 });
1420
1421 let start = Point::new(buffer_row_range.start, 0);
1422 let end = Point::new(buffer_row_range.end, 0);
1423 let buffer_range = buffer.anchor_before(start)..buffer.anchor_before(end);
1424
1425 let base_line_count = line_item_count.saturating_sub(buffer_row_range.len());
1426
1427 let (base_word_diffs, buffer_word_diffs) = if let Some(diff_options) = diff_options
1428 && !buffer_row_range.is_empty()
1429 && base_line_count == buffer_row_range.len()
1430 && diff_options.max_word_diff_line_count >= base_line_count
1431 {
1432 let base_text: String = diff_base
1433 .chunks_in_range(diff_base_byte_range.clone())
1434 .collect();
1435
1436 let buffer_text: String = buffer.text_for_range(buffer_range.clone()).collect();
1437
1438 let (base_word_diffs, buffer_word_diffs_relative) = word_diff_ranges(
1439 &base_text,
1440 &buffer_text,
1441 DiffOptions {
1442 language_scope: diff_options.language_scope.clone(),
1443 ..*diff_options
1444 },
1445 );
1446
1447 let buffer_start_offset = buffer_range.start.to_offset(buffer);
1448 let buffer_word_diffs = buffer_word_diffs_relative
1449 .into_iter()
1450 .map(|range| {
1451 let start = buffer.anchor_after(buffer_start_offset + range.start);
1452 let end = buffer.anchor_after(buffer_start_offset + range.end);
1453 start..end
1454 })
1455 .collect();
1456
1457 (base_word_diffs, buffer_word_diffs)
1458 } else {
1459 (Vec::default(), Vec::default())
1460 };
1461
1462 InternalDiffHunk {
1463 buffer_range,
1464 diff_base_byte_range,
1465 base_word_diffs,
1466 buffer_word_diffs,
1467 }
1468}
1469
1470impl std::fmt::Debug for BufferDiff {
1471 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
1472 f.debug_struct("BufferChangeSet")
1473 .field("buffer_id", &self.buffer_id)
1474 .finish()
1475 }
1476}
1477
1478#[derive(Clone, Debug, Default)]
1479pub struct DiffChanged {
1480 pub changed_range: Option<Range<text::Anchor>>,
1481 pub base_text_changed_range: Option<Range<usize>>,
1482 pub extended_range: Option<Range<text::Anchor>>,
1483}
1484
1485#[derive(Clone, Debug)]
1486pub enum BufferDiffEvent {
1487 DiffChanged(DiffChanged),
1488 LanguageChanged,
1489 HunksStagedOrUnstaged(Option<Rope>),
1490}
1491
1492impl EventEmitter<BufferDiffEvent> for BufferDiff {}
1493
1494impl BufferDiff {
1495 pub fn new(buffer: &text::BufferSnapshot, cx: &mut App) -> Self {
1496 let base_text = cx.new(|cx| {
1497 let mut buffer = language::Buffer::local("", cx);
1498 buffer.set_capability(Capability::ReadOnly, cx);
1499 buffer
1500 });
1501
1502 BufferDiff {
1503 buffer_id: buffer.remote_id(),
1504 inner: BufferDiffInner {
1505 base_text,
1506 hunks: SumTree::new(buffer),
1507 pending_hunks: SumTree::new(buffer),
1508 base_text_exists: false,
1509 buffer_snapshot: buffer.clone(),
1510 },
1511 secondary_diff: None,
1512 }
1513 }
1514
1515 pub fn new_unchanged(buffer: &text::BufferSnapshot, cx: &mut Context<Self>) -> Self {
1516 let base_text = buffer.text();
1517 let base_text = cx.new(|cx| {
1518 let mut buffer = language::Buffer::local(base_text, cx);
1519 buffer.set_capability(Capability::ReadOnly, cx);
1520 buffer
1521 });
1522
1523 BufferDiff {
1524 buffer_id: buffer.remote_id(),
1525 inner: BufferDiffInner {
1526 base_text,
1527 hunks: SumTree::new(buffer),
1528 pending_hunks: SumTree::new(buffer),
1529 base_text_exists: true,
1530 buffer_snapshot: buffer.clone(),
1531 },
1532 secondary_diff: None,
1533 }
1534 }
1535
1536 #[cfg(any(test, feature = "test-support"))]
1537 pub fn new_with_base_text(
1538 base_text: &str,
1539 buffer: &text::BufferSnapshot,
1540 cx: &mut Context<Self>,
1541 ) -> Self {
1542 let mut this = BufferDiff::new(&buffer, cx);
1543 let mut base_text = base_text.to_owned();
1544 text::LineEnding::normalize(&mut base_text);
1545 let inner = cx.foreground_executor().block_on(this.update_diff(
1546 buffer.clone(),
1547 Some(Arc::from(base_text)),
1548 Some(false),
1549 None,
1550 cx,
1551 ));
1552 this.set_snapshot(inner, &buffer, cx).detach();
1553 this
1554 }
1555
1556 pub fn set_secondary_diff(&mut self, diff: Entity<BufferDiff>) {
1557 self.secondary_diff = Some(diff);
1558 }
1559
1560 pub fn secondary_diff(&self) -> Option<Entity<BufferDiff>> {
1561 self.secondary_diff.clone()
1562 }
1563
1564 pub fn clear_pending_hunks(&mut self, cx: &mut Context<Self>) {
1565 if self.secondary_diff.is_some() {
1566 self.inner.pending_hunks = SumTree::from_summary(DiffHunkSummary {
1567 buffer_range: Anchor::min_min_range_for_buffer(self.buffer_id),
1568 diff_base_byte_range: 0..0,
1569 });
1570 let changed_range = Some(Anchor::min_max_range_for_buffer(self.buffer_id));
1571 let base_text_range = Some(0..self.base_text(cx).len());
1572 cx.emit(BufferDiffEvent::DiffChanged(DiffChanged {
1573 changed_range: changed_range.clone(),
1574 base_text_changed_range: base_text_range,
1575 extended_range: changed_range,
1576 }));
1577 }
1578 }
1579
1580 pub fn stage_or_unstage_hunks(
1581 &mut self,
1582 stage: bool,
1583 hunks: &[DiffHunk],
1584 buffer: &text::BufferSnapshot,
1585 file_exists: bool,
1586 cx: &mut Context<Self>,
1587 ) -> Option<Rope> {
1588 let new_index_text = self
1589 .secondary_diff
1590 .as_ref()?
1591 .update(cx, |secondary_diff, cx| {
1592 self.inner.stage_or_unstage_hunks_impl(
1593 &secondary_diff.inner,
1594 stage,
1595 hunks,
1596 buffer,
1597 file_exists,
1598 cx,
1599 )
1600 });
1601
1602 cx.emit(BufferDiffEvent::HunksStagedOrUnstaged(
1603 new_index_text.clone(),
1604 ));
1605 if let Some((first, last)) = hunks.first().zip(hunks.last()) {
1606 let changed_range = Some(first.buffer_range.start..last.buffer_range.end);
1607 let base_text_changed_range =
1608 Some(first.diff_base_byte_range.start..last.diff_base_byte_range.end);
1609 cx.emit(BufferDiffEvent::DiffChanged(DiffChanged {
1610 changed_range: changed_range.clone(),
1611 base_text_changed_range,
1612 extended_range: changed_range,
1613 }));
1614 }
1615 new_index_text
1616 }
1617
1618 pub fn stage_or_unstage_all_hunks(
1619 &mut self,
1620 stage: bool,
1621 buffer: &text::BufferSnapshot,
1622 file_exists: bool,
1623 cx: &mut Context<Self>,
1624 ) {
1625 let hunks = self
1626 .snapshot(cx)
1627 .hunks_intersecting_range(Anchor::MIN..Anchor::MAX, buffer)
1628 .collect::<Vec<_>>();
1629 let Some(secondary) = self.secondary_diff.clone() else {
1630 return;
1631 };
1632 let secondary = secondary.read(cx).inner.clone();
1633 self.inner
1634 .stage_or_unstage_hunks_impl(&secondary, stage, &hunks, buffer, file_exists, cx);
1635 if let Some((first, last)) = hunks.first().zip(hunks.last()) {
1636 let changed_range = Some(first.buffer_range.start..last.buffer_range.end);
1637 let base_text_changed_range =
1638 Some(first.diff_base_byte_range.start..last.diff_base_byte_range.end);
1639 cx.emit(BufferDiffEvent::DiffChanged(DiffChanged {
1640 changed_range: changed_range.clone(),
1641 base_text_changed_range,
1642 extended_range: changed_range,
1643 }));
1644 }
1645 }
1646
1647 pub fn update_diff(
1648 &self,
1649 buffer: text::BufferSnapshot,
1650 base_text: Option<Arc<str>>,
1651 base_text_change: Option<bool>,
1652 language: Option<Arc<Language>>,
1653 cx: &App,
1654 ) -> Task<BufferDiffUpdate> {
1655 let prev_base_text = self.base_text(cx).as_rope().clone();
1656 let base_text_changed = base_text_change.is_some();
1657 let compute_base_text_edits = base_text_change == Some(true);
1658 let diff_options = build_diff_options(
1659 None,
1660 language.as_ref().map(|l| l.name()),
1661 language.as_ref().map(|l| l.default_scope()),
1662 cx,
1663 );
1664 let buffer_snapshot = buffer.clone();
1665
1666 let base_text_diff_task = if base_text_changed && compute_base_text_edits {
1667 base_text
1668 .as_ref()
1669 .map(|new_text| self.inner.base_text.read(cx).diff(new_text.clone(), cx))
1670 } else {
1671 None
1672 };
1673
1674 let hunk_task = cx.background_executor().spawn({
1675 let buffer_snapshot = buffer_snapshot.clone();
1676 async move {
1677 let base_text_rope = if let Some(base_text) = &base_text {
1678 if base_text_changed {
1679 Rope::from(base_text.as_ref())
1680 } else {
1681 prev_base_text
1682 }
1683 } else {
1684 Rope::new()
1685 };
1686 let base_text_exists = base_text.is_some();
1687 let hunks = compute_hunks(
1688 base_text
1689 .clone()
1690 .map(|base_text| (base_text, base_text_rope.clone())),
1691 &buffer,
1692 diff_options,
1693 );
1694 let base_text = base_text.unwrap_or_default();
1695 BufferDiffInner {
1696 base_text,
1697 hunks,
1698 base_text_exists,
1699 pending_hunks: SumTree::new(&buffer),
1700 buffer_snapshot,
1701 }
1702 }
1703 });
1704
1705 cx.background_executor().spawn(async move {
1706 let (inner, base_text_edits) = match base_text_diff_task {
1707 Some(diff_task) => {
1708 let (inner, diff) = futures::join!(hunk_task, diff_task);
1709 (inner, Some(diff))
1710 }
1711 None => (hunk_task.await, None),
1712 };
1713
1714 BufferDiffUpdate {
1715 inner,
1716 buffer_snapshot,
1717 base_text_edits,
1718 base_text_changed,
1719 }
1720 })
1721 }
1722
1723 #[ztracing::instrument(skip_all)]
1724 pub fn language_changed(
1725 &mut self,
1726 language: Option<Arc<Language>>,
1727 language_registry: Option<Arc<LanguageRegistry>>,
1728 cx: &mut Context<Self>,
1729 ) {
1730 let fut = self.inner.base_text.update(cx, |base_text, cx| {
1731 if let Some(language_registry) = language_registry {
1732 base_text.set_language_registry(language_registry);
1733 }
1734 base_text.set_language_async(language, cx);
1735 base_text.parsing_idle()
1736 });
1737 cx.spawn(async move |this, cx| {
1738 fut.await;
1739 this.update(cx, |_, cx| {
1740 cx.emit(BufferDiffEvent::LanguageChanged);
1741 })
1742 .ok();
1743 })
1744 .detach();
1745 }
1746
1747 fn set_snapshot_with_secondary_inner(
1748 &mut self,
1749 update: BufferDiffUpdate,
1750 buffer: &text::BufferSnapshot,
1751 secondary_diff_change: Option<Range<Anchor>>,
1752 clear_pending_hunks: bool,
1753 cx: &mut Context<Self>,
1754 ) -> impl Future<Output = DiffChanged> + use<> {
1755 log::debug!("set snapshot with secondary {secondary_diff_change:?}");
1756
1757 let old_snapshot = self.snapshot(cx);
1758 let new_state = update.inner;
1759 let base_text_changed = update.base_text_changed;
1760
1761 let state = &mut self.inner;
1762 state.base_text_exists = new_state.base_text_exists;
1763 let should_compare_hunks = update.base_text_edits.is_some() || !base_text_changed;
1764 let parsing_idle = if let Some(diff) = update.base_text_edits {
1765 state.base_text.update(cx, |base_text, cx| {
1766 base_text.set_sync_parse_timeout(None);
1767 base_text.set_capability(Capability::ReadWrite, cx);
1768 base_text.apply_diff(diff, cx);
1769 base_text.set_capability(Capability::ReadOnly, cx);
1770 Some(base_text.parsing_idle())
1771 })
1772 } else if update.base_text_changed {
1773 state.base_text.update(cx, |base_text, cx| {
1774 base_text.set_sync_parse_timeout(None);
1775 base_text.set_capability(Capability::ReadWrite, cx);
1776 base_text.set_text(new_state.base_text.clone(), cx);
1777 base_text.set_capability(Capability::ReadOnly, cx);
1778 Some(base_text.parsing_idle())
1779 })
1780 } else {
1781 None
1782 };
1783
1784 let old_buffer_snapshot = &old_snapshot.inner.buffer_snapshot;
1785 let old_base_snapshot = &old_snapshot.inner.base_text;
1786 let new_base_snapshot = state.base_text.read(cx).snapshot();
1787 let DiffChanged {
1788 mut changed_range,
1789 mut base_text_changed_range,
1790 mut extended_range,
1791 } = match (state.base_text_exists, new_state.base_text_exists) {
1792 (false, false) => DiffChanged::default(),
1793 (true, true) if should_compare_hunks => compare_hunks(
1794 &new_state.hunks,
1795 &old_snapshot.inner.hunks,
1796 old_buffer_snapshot,
1797 buffer,
1798 old_base_snapshot,
1799 &new_base_snapshot,
1800 ),
1801 _ => {
1802 let full_range = text::Anchor::min_max_range_for_buffer(self.buffer_id);
1803 let full_base_range = 0..new_state.base_text.len();
1804 DiffChanged {
1805 changed_range: Some(full_range.clone()),
1806 base_text_changed_range: Some(full_base_range),
1807 extended_range: Some(full_range),
1808 }
1809 }
1810 };
1811 state.hunks = new_state.hunks;
1812 state.buffer_snapshot = update.buffer_snapshot;
1813
1814 if base_text_changed || clear_pending_hunks {
1815 if let Some((first, last)) = state.pending_hunks.first().zip(state.pending_hunks.last())
1816 {
1817 let pending_range = first.buffer_range.start..last.buffer_range.end;
1818 if let Some(range) = &mut changed_range {
1819 range.start = *range.start.min(&pending_range.start, buffer);
1820 range.end = *range.end.max(&pending_range.end, buffer);
1821 } else {
1822 changed_range = Some(pending_range.clone());
1823 }
1824
1825 if let Some(base_text_range) = base_text_changed_range.as_mut() {
1826 base_text_range.start =
1827 base_text_range.start.min(first.diff_base_byte_range.start);
1828 base_text_range.end = base_text_range.end.max(last.diff_base_byte_range.end);
1829 } else {
1830 base_text_changed_range =
1831 Some(first.diff_base_byte_range.start..last.diff_base_byte_range.end);
1832 }
1833
1834 if let Some(ext) = &mut extended_range {
1835 ext.start = *ext.start.min(&pending_range.start, buffer);
1836 ext.end = *ext.end.max(&pending_range.end, buffer);
1837 } else {
1838 extended_range = Some(pending_range);
1839 }
1840 }
1841 state.pending_hunks = SumTree::new(buffer);
1842 }
1843
1844 if let Some(secondary_changed_range) = secondary_diff_change
1845 && let (Some(secondary_hunk_range), Some(secondary_base_range)) =
1846 old_snapshot.range_to_hunk_range(secondary_changed_range, buffer)
1847 {
1848 if let Some(range) = &mut changed_range {
1849 range.start = *secondary_hunk_range.start.min(&range.start, buffer);
1850 range.end = *secondary_hunk_range.end.max(&range.end, buffer);
1851 } else {
1852 changed_range = Some(secondary_hunk_range.clone());
1853 }
1854
1855 if let Some(base_text_range) = base_text_changed_range.as_mut() {
1856 base_text_range.start = secondary_base_range.start.min(base_text_range.start);
1857 base_text_range.end = secondary_base_range.end.max(base_text_range.end);
1858 } else {
1859 base_text_changed_range = Some(secondary_base_range);
1860 }
1861
1862 if let Some(ext) = &mut extended_range {
1863 ext.start = *ext.start.min(&secondary_hunk_range.start, buffer);
1864 ext.end = *ext.end.max(&secondary_hunk_range.end, buffer);
1865 } else {
1866 extended_range = Some(secondary_hunk_range);
1867 }
1868 }
1869
1870 async move {
1871 if let Some(parsing_idle) = parsing_idle {
1872 parsing_idle.await;
1873 }
1874 DiffChanged {
1875 changed_range,
1876 base_text_changed_range,
1877 extended_range,
1878 }
1879 }
1880 }
1881
1882 pub fn set_snapshot(
1883 &mut self,
1884 new_state: BufferDiffUpdate,
1885 buffer: &text::BufferSnapshot,
1886 cx: &mut Context<Self>,
1887 ) -> Task<Option<Range<Anchor>>> {
1888 self.set_snapshot_with_secondary(new_state, buffer, None, false, cx)
1889 }
1890
1891 pub fn set_snapshot_with_secondary(
1892 &mut self,
1893 update: BufferDiffUpdate,
1894 buffer: &text::BufferSnapshot,
1895 secondary_diff_change: Option<Range<Anchor>>,
1896 clear_pending_hunks: bool,
1897 cx: &mut Context<Self>,
1898 ) -> Task<Option<Range<Anchor>>> {
1899 let fut = self.set_snapshot_with_secondary_inner(
1900 update,
1901 buffer,
1902 secondary_diff_change,
1903 clear_pending_hunks,
1904 cx,
1905 );
1906
1907 cx.spawn(async move |this, cx| {
1908 let change = fut.await;
1909 this.update(cx, |_, cx| {
1910 cx.emit(BufferDiffEvent::DiffChanged(change.clone()));
1911 })
1912 .ok();
1913 change.changed_range
1914 })
1915 }
1916
1917 pub fn base_text(&self, cx: &App) -> language::BufferSnapshot {
1918 self.inner.base_text.read(cx).snapshot()
1919 }
1920
1921 pub fn base_text_exists(&self) -> bool {
1922 self.inner.base_text_exists
1923 }
1924
1925 pub fn snapshot(&self, cx: &App) -> BufferDiffSnapshot {
1926 BufferDiffSnapshot {
1927 inner: BufferDiffInner {
1928 hunks: self.inner.hunks.clone(),
1929 pending_hunks: self.inner.pending_hunks.clone(),
1930 base_text: self.inner.base_text.read(cx).snapshot(),
1931 base_text_exists: self.inner.base_text_exists,
1932 buffer_snapshot: self.inner.buffer_snapshot.clone(),
1933 },
1934 secondary_diff: self.secondary_diff.as_ref().map(|diff| {
1935 debug_assert!(diff.read(cx).secondary_diff.is_none());
1936 Arc::new(diff.read(cx).snapshot(cx))
1937 }),
1938 }
1939 }
1940
1941 /// Used in cases where the change set isn't derived from git.
1942 pub fn set_base_text(
1943 &mut self,
1944 base_text: Option<Arc<str>>,
1945 language: Option<Arc<Language>>,
1946 buffer: text::BufferSnapshot,
1947 cx: &mut Context<Self>,
1948 ) -> oneshot::Receiver<()> {
1949 let (tx, rx) = oneshot::channel();
1950 let complete_on_drop = util::defer(|| {
1951 tx.send(()).ok();
1952 });
1953 cx.spawn(async move |this, cx| {
1954 let Some(state) = this
1955 .update(cx, |this, cx| {
1956 this.update_diff(buffer.clone(), base_text, Some(false), language, cx)
1957 })
1958 .log_err()
1959 else {
1960 return;
1961 };
1962 let state = state.await;
1963 if let Some(task) = this
1964 .update(cx, |this, cx| this.set_snapshot(state, &buffer, cx))
1965 .log_err()
1966 {
1967 task.await;
1968 }
1969 drop(complete_on_drop)
1970 })
1971 .detach();
1972 rx
1973 }
1974
1975 pub fn base_text_string(&self, cx: &App) -> Option<String> {
1976 self.inner
1977 .base_text_exists
1978 .then(|| self.inner.base_text.read(cx).text())
1979 }
1980
1981 #[cfg(any(test, feature = "test-support"))]
1982 pub fn recalculate_diff_sync(&mut self, buffer: &text::BufferSnapshot, cx: &mut Context<Self>) {
1983 let language = self.base_text(cx).language().cloned();
1984 let base_text = self.base_text_string(cx).map(|s| s.as_str().into());
1985 let fut = self.update_diff(buffer.clone(), base_text, None, language, cx);
1986 let fg_executor = cx.foreground_executor().clone();
1987 let snapshot = fg_executor.block_on(fut);
1988 let fut = self.set_snapshot_with_secondary_inner(snapshot, buffer, None, false, cx);
1989 let change = fg_executor.block_on(fut);
1990 cx.emit(BufferDiffEvent::DiffChanged(change));
1991 }
1992
1993 pub fn base_text_buffer(&self) -> &Entity<language::Buffer> {
1994 &self.inner.base_text
1995 }
1996}
1997
1998impl DiffHunk {
1999 pub fn is_created_file(&self) -> bool {
2000 self.diff_base_byte_range == (0..0)
2001 && self.buffer_range.start.is_min()
2002 && self.buffer_range.end.is_max()
2003 }
2004
2005 pub fn status(&self) -> DiffHunkStatus {
2006 let kind = if self.buffer_range.start == self.buffer_range.end {
2007 DiffHunkStatusKind::Deleted
2008 } else if self.diff_base_byte_range.is_empty() {
2009 DiffHunkStatusKind::Added
2010 } else {
2011 DiffHunkStatusKind::Modified
2012 };
2013 DiffHunkStatus {
2014 kind,
2015 secondary: self.secondary_status,
2016 }
2017 }
2018}
2019
2020impl DiffHunkStatus {
2021 pub fn has_secondary_hunk(&self) -> bool {
2022 matches!(
2023 self.secondary,
2024 DiffHunkSecondaryStatus::HasSecondaryHunk
2025 | DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
2026 | DiffHunkSecondaryStatus::OverlapsWithSecondaryHunk
2027 )
2028 }
2029
2030 pub fn is_pending(&self) -> bool {
2031 matches!(
2032 self.secondary,
2033 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
2034 | DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
2035 )
2036 }
2037
2038 pub fn is_deleted(&self) -> bool {
2039 self.kind == DiffHunkStatusKind::Deleted
2040 }
2041
2042 pub fn is_added(&self) -> bool {
2043 self.kind == DiffHunkStatusKind::Added
2044 }
2045
2046 pub fn is_modified(&self) -> bool {
2047 self.kind == DiffHunkStatusKind::Modified
2048 }
2049
2050 pub fn added(secondary: DiffHunkSecondaryStatus) -> Self {
2051 Self {
2052 kind: DiffHunkStatusKind::Added,
2053 secondary,
2054 }
2055 }
2056
2057 pub fn modified(secondary: DiffHunkSecondaryStatus) -> Self {
2058 Self {
2059 kind: DiffHunkStatusKind::Modified,
2060 secondary,
2061 }
2062 }
2063
2064 pub fn deleted(secondary: DiffHunkSecondaryStatus) -> Self {
2065 Self {
2066 kind: DiffHunkStatusKind::Deleted,
2067 secondary,
2068 }
2069 }
2070
2071 pub fn deleted_none() -> Self {
2072 Self {
2073 kind: DiffHunkStatusKind::Deleted,
2074 secondary: DiffHunkSecondaryStatus::NoSecondaryHunk,
2075 }
2076 }
2077
2078 pub fn added_none() -> Self {
2079 Self {
2080 kind: DiffHunkStatusKind::Added,
2081 secondary: DiffHunkSecondaryStatus::NoSecondaryHunk,
2082 }
2083 }
2084
2085 pub fn modified_none() -> Self {
2086 Self {
2087 kind: DiffHunkStatusKind::Modified,
2088 secondary: DiffHunkSecondaryStatus::NoSecondaryHunk,
2089 }
2090 }
2091}
2092
2093#[cfg(any(test, feature = "test-support"))]
2094#[track_caller]
2095pub fn assert_hunks<ExpectedText, HunkIter>(
2096 diff_hunks: HunkIter,
2097 buffer: &text::BufferSnapshot,
2098 diff_base: &str,
2099 // Line range, deleted, added, status
2100 expected_hunks: &[(Range<u32>, ExpectedText, ExpectedText, DiffHunkStatus)],
2101) where
2102 HunkIter: Iterator<Item = DiffHunk>,
2103 ExpectedText: AsRef<str>,
2104{
2105 let actual_hunks = diff_hunks
2106 .map(|hunk| {
2107 (
2108 hunk.range.clone(),
2109 &diff_base[hunk.diff_base_byte_range.clone()],
2110 buffer
2111 .text_for_range(hunk.range.clone())
2112 .collect::<String>(),
2113 hunk.status(),
2114 )
2115 })
2116 .collect::<Vec<_>>();
2117
2118 let expected_hunks: Vec<_> = expected_hunks
2119 .iter()
2120 .map(|(line_range, deleted_text, added_text, status)| {
2121 (
2122 Point::new(line_range.start, 0)..Point::new(line_range.end, 0),
2123 deleted_text.as_ref(),
2124 added_text.as_ref().to_string(),
2125 *status,
2126 )
2127 })
2128 .collect();
2129
2130 pretty_assertions::assert_eq!(actual_hunks, expected_hunks);
2131}
2132
2133#[cfg(test)]
2134mod tests {
2135 use std::{fmt::Write as _, sync::mpsc};
2136
2137 use super::*;
2138 use gpui::TestAppContext;
2139 use pretty_assertions::{assert_eq, assert_ne};
2140 use rand::{Rng as _, rngs::StdRng};
2141 use text::{Buffer, BufferId, ReplicaId, Rope};
2142 use unindent::Unindent as _;
2143 use util::test::marked_text_ranges;
2144
2145 #[ctor::ctor]
2146 fn init_logger() {
2147 zlog::init_test();
2148 }
2149
2150 #[gpui::test]
2151 async fn test_buffer_diff_simple(cx: &mut gpui::TestAppContext) {
2152 let diff_base = "
2153 one
2154 two
2155 three
2156 "
2157 .unindent();
2158
2159 let buffer_text = "
2160 one
2161 HELLO
2162 three
2163 "
2164 .unindent();
2165
2166 let mut buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2167 let mut diff = BufferDiffSnapshot::new_sync(&buffer, diff_base.clone(), cx);
2168 assert_hunks(
2169 diff.hunks_intersecting_range(
2170 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2171 &buffer,
2172 ),
2173 &buffer,
2174 &diff_base,
2175 &[(1..2, "two\n", "HELLO\n", DiffHunkStatus::modified_none())],
2176 );
2177
2178 buffer.edit([(0..0, "point five\n")]);
2179 diff = BufferDiffSnapshot::new_sync(&buffer, diff_base.clone(), cx);
2180 assert_hunks(
2181 diff.hunks_intersecting_range(
2182 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2183 &buffer,
2184 ),
2185 &buffer,
2186 &diff_base,
2187 &[
2188 (0..1, "", "point five\n", DiffHunkStatus::added_none()),
2189 (2..3, "two\n", "HELLO\n", DiffHunkStatus::modified_none()),
2190 ],
2191 );
2192
2193 diff = cx.update(|cx| BufferDiff::new(&buffer, cx).snapshot(cx));
2194 assert_hunks::<&str, _>(
2195 diff.hunks_intersecting_range(
2196 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2197 &buffer,
2198 ),
2199 &buffer,
2200 &diff_base,
2201 &[],
2202 );
2203 }
2204
2205 #[gpui::test]
2206 async fn test_buffer_diff_with_secondary(cx: &mut gpui::TestAppContext) {
2207 let head_text = "
2208 zero
2209 one
2210 two
2211 three
2212 four
2213 five
2214 six
2215 seven
2216 eight
2217 nine
2218 "
2219 .unindent();
2220
2221 let index_text = "
2222 zero
2223 one
2224 TWO
2225 three
2226 FOUR
2227 five
2228 six
2229 seven
2230 eight
2231 NINE
2232 "
2233 .unindent();
2234
2235 let buffer_text = "
2236 zero
2237 one
2238 TWO
2239 three
2240 FOUR
2241 FIVE
2242 six
2243 SEVEN
2244 eight
2245 nine
2246 "
2247 .unindent();
2248
2249 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2250 let unstaged_diff = BufferDiffSnapshot::new_sync(&buffer, index_text, cx);
2251 let mut uncommitted_diff = BufferDiffSnapshot::new_sync(&buffer, head_text.clone(), cx);
2252 uncommitted_diff.secondary_diff = Some(Arc::new(unstaged_diff));
2253
2254 let expected_hunks = vec![
2255 (2..3, "two\n", "TWO\n", DiffHunkStatus::modified_none()),
2256 (
2257 4..6,
2258 "four\nfive\n",
2259 "FOUR\nFIVE\n",
2260 DiffHunkStatus::modified(DiffHunkSecondaryStatus::OverlapsWithSecondaryHunk),
2261 ),
2262 (
2263 7..8,
2264 "seven\n",
2265 "SEVEN\n",
2266 DiffHunkStatus::modified(DiffHunkSecondaryStatus::HasSecondaryHunk),
2267 ),
2268 ];
2269
2270 assert_hunks(
2271 uncommitted_diff.hunks_intersecting_range(
2272 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2273 &buffer,
2274 ),
2275 &buffer,
2276 &head_text,
2277 &expected_hunks,
2278 );
2279 }
2280
2281 #[gpui::test]
2282 async fn test_buffer_diff_range(cx: &mut TestAppContext) {
2283 let diff_base = "
2284 one
2285 two
2286 three
2287 four
2288 five
2289 six
2290 seven
2291 eight
2292 nine
2293 ten
2294 "
2295 .unindent();
2296
2297 let buffer_text = "
2298 A
2299 one
2300 B
2301 two
2302 C
2303 three
2304 HELLO
2305 four
2306 five
2307 SIXTEEN
2308 seven
2309 eight
2310 WORLD
2311 nine
2312
2313 ten
2314
2315 "
2316 .unindent();
2317
2318 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2319 let diff = BufferDiffSnapshot::new_sync(buffer.snapshot(), diff_base.clone(), cx);
2320 assert_eq!(
2321 diff.hunks_intersecting_range(
2322 Anchor::min_max_range_for_buffer(buffer.remote_id()),
2323 &buffer
2324 )
2325 .count(),
2326 8
2327 );
2328
2329 assert_hunks(
2330 diff.hunks_intersecting_range(
2331 buffer.anchor_before(Point::new(7, 0))..buffer.anchor_before(Point::new(12, 0)),
2332 &buffer,
2333 ),
2334 &buffer,
2335 &diff_base,
2336 &[
2337 (6..7, "", "HELLO\n", DiffHunkStatus::added_none()),
2338 (9..10, "six\n", "SIXTEEN\n", DiffHunkStatus::modified_none()),
2339 (12..13, "", "WORLD\n", DiffHunkStatus::added_none()),
2340 ],
2341 );
2342 }
2343
2344 #[gpui::test]
2345 async fn test_stage_hunk(cx: &mut TestAppContext) {
2346 struct Example {
2347 name: &'static str,
2348 head_text: String,
2349 index_text: String,
2350 buffer_marked_text: String,
2351 final_index_text: String,
2352 }
2353
2354 let table = [
2355 Example {
2356 name: "uncommitted hunk straddles end of unstaged hunk",
2357 head_text: "
2358 one
2359 two
2360 three
2361 four
2362 five
2363 "
2364 .unindent(),
2365 index_text: "
2366 one
2367 TWO_HUNDRED
2368 three
2369 FOUR_HUNDRED
2370 five
2371 "
2372 .unindent(),
2373 buffer_marked_text: "
2374 ZERO
2375 one
2376 two
2377 «THREE_HUNDRED
2378 FOUR_HUNDRED»
2379 five
2380 SIX
2381 "
2382 .unindent(),
2383 final_index_text: "
2384 one
2385 two
2386 THREE_HUNDRED
2387 FOUR_HUNDRED
2388 five
2389 "
2390 .unindent(),
2391 },
2392 Example {
2393 name: "uncommitted hunk straddles start of unstaged hunk",
2394 head_text: "
2395 one
2396 two
2397 three
2398 four
2399 five
2400 "
2401 .unindent(),
2402 index_text: "
2403 one
2404 TWO_HUNDRED
2405 three
2406 FOUR_HUNDRED
2407 five
2408 "
2409 .unindent(),
2410 buffer_marked_text: "
2411 ZERO
2412 one
2413 «TWO_HUNDRED
2414 THREE_HUNDRED»
2415 four
2416 five
2417 SIX
2418 "
2419 .unindent(),
2420 final_index_text: "
2421 one
2422 TWO_HUNDRED
2423 THREE_HUNDRED
2424 four
2425 five
2426 "
2427 .unindent(),
2428 },
2429 Example {
2430 name: "uncommitted hunk strictly contains unstaged hunks",
2431 head_text: "
2432 one
2433 two
2434 three
2435 four
2436 five
2437 six
2438 seven
2439 "
2440 .unindent(),
2441 index_text: "
2442 one
2443 TWO
2444 THREE
2445 FOUR
2446 FIVE
2447 SIX
2448 seven
2449 "
2450 .unindent(),
2451 buffer_marked_text: "
2452 one
2453 TWO
2454 «THREE_HUNDRED
2455 FOUR
2456 FIVE_HUNDRED»
2457 SIX
2458 seven
2459 "
2460 .unindent(),
2461 final_index_text: "
2462 one
2463 TWO
2464 THREE_HUNDRED
2465 FOUR
2466 FIVE_HUNDRED
2467 SIX
2468 seven
2469 "
2470 .unindent(),
2471 },
2472 Example {
2473 name: "uncommitted deletion hunk",
2474 head_text: "
2475 one
2476 two
2477 three
2478 four
2479 five
2480 "
2481 .unindent(),
2482 index_text: "
2483 one
2484 two
2485 three
2486 four
2487 five
2488 "
2489 .unindent(),
2490 buffer_marked_text: "
2491 one
2492 ˇfive
2493 "
2494 .unindent(),
2495 final_index_text: "
2496 one
2497 five
2498 "
2499 .unindent(),
2500 },
2501 Example {
2502 name: "one unstaged hunk that contains two uncommitted hunks",
2503 head_text: "
2504 one
2505 two
2506
2507 three
2508 four
2509 "
2510 .unindent(),
2511 index_text: "
2512 one
2513 two
2514 three
2515 four
2516 "
2517 .unindent(),
2518 buffer_marked_text: "
2519 «one
2520
2521 three // modified
2522 four»
2523 "
2524 .unindent(),
2525 final_index_text: "
2526 one
2527
2528 three // modified
2529 four
2530 "
2531 .unindent(),
2532 },
2533 Example {
2534 name: "one uncommitted hunk that contains two unstaged hunks",
2535 head_text: "
2536 one
2537 two
2538 three
2539 four
2540 five
2541 "
2542 .unindent(),
2543 index_text: "
2544 ZERO
2545 one
2546 TWO
2547 THREE
2548 FOUR
2549 five
2550 "
2551 .unindent(),
2552 buffer_marked_text: "
2553 «one
2554 TWO_HUNDRED
2555 THREE
2556 FOUR_HUNDRED
2557 five»
2558 "
2559 .unindent(),
2560 final_index_text: "
2561 ZERO
2562 one
2563 TWO_HUNDRED
2564 THREE
2565 FOUR_HUNDRED
2566 five
2567 "
2568 .unindent(),
2569 },
2570 ];
2571
2572 for example in table {
2573 let (buffer_text, ranges) = marked_text_ranges(&example.buffer_marked_text, false);
2574 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2575 let hunk_range =
2576 buffer.anchor_before(ranges[0].start)..buffer.anchor_before(ranges[0].end);
2577
2578 let unstaged_diff =
2579 cx.new(|cx| BufferDiff::new_with_base_text(&example.index_text, &buffer, cx));
2580
2581 let uncommitted_diff = cx.new(|cx| {
2582 let mut diff = BufferDiff::new_with_base_text(&example.head_text, &buffer, cx);
2583 diff.set_secondary_diff(unstaged_diff);
2584 diff
2585 });
2586
2587 uncommitted_diff.update(cx, |diff, cx| {
2588 let hunks = diff
2589 .snapshot(cx)
2590 .hunks_intersecting_range(hunk_range.clone(), &buffer)
2591 .collect::<Vec<_>>();
2592 for hunk in &hunks {
2593 assert_ne!(
2594 hunk.secondary_status,
2595 DiffHunkSecondaryStatus::NoSecondaryHunk
2596 )
2597 }
2598
2599 let new_index_text = diff
2600 .stage_or_unstage_hunks(true, &hunks, &buffer, true, cx)
2601 .unwrap()
2602 .to_string();
2603
2604 let hunks = diff
2605 .snapshot(cx)
2606 .hunks_intersecting_range(hunk_range.clone(), &buffer)
2607 .collect::<Vec<_>>();
2608 for hunk in &hunks {
2609 assert_eq!(
2610 hunk.secondary_status,
2611 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
2612 )
2613 }
2614
2615 pretty_assertions::assert_eq!(
2616 new_index_text,
2617 example.final_index_text,
2618 "example: {}",
2619 example.name
2620 );
2621 });
2622 }
2623 }
2624
2625 #[gpui::test]
2626 async fn test_stage_all_with_nested_hunks(cx: &mut TestAppContext) {
2627 // This test reproduces a crash where staging all hunks would cause an underflow
2628 // when there's one large unstaged hunk containing multiple uncommitted hunks.
2629 let head_text = "
2630 aaa
2631 bbb
2632 ccc
2633 ddd
2634 eee
2635 fff
2636 ggg
2637 hhh
2638 iii
2639 jjj
2640 kkk
2641 lll
2642 "
2643 .unindent();
2644
2645 let index_text = "
2646 aaa
2647 bbb
2648 CCC-index
2649 DDD-index
2650 EEE-index
2651 FFF-index
2652 GGG-index
2653 HHH-index
2654 III-index
2655 JJJ-index
2656 kkk
2657 lll
2658 "
2659 .unindent();
2660
2661 let buffer_text = "
2662 aaa
2663 bbb
2664 ccc-modified
2665 ddd
2666 eee-modified
2667 fff
2668 ggg
2669 hhh-modified
2670 iii
2671 jjj
2672 kkk
2673 lll
2674 "
2675 .unindent();
2676
2677 let buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
2678
2679 let unstaged_diff = cx.new(|cx| BufferDiff::new_with_base_text(&index_text, &buffer, cx));
2680 let uncommitted_diff = cx.new(|cx| {
2681 let mut diff = BufferDiff::new_with_base_text(&head_text, &buffer, cx);
2682 diff.set_secondary_diff(unstaged_diff);
2683 diff
2684 });
2685
2686 uncommitted_diff.update(cx, |diff, cx| {
2687 diff.stage_or_unstage_all_hunks(true, &buffer, true, cx);
2688 });
2689 }
2690
2691 #[gpui::test]
2692 async fn test_stage_all_with_stale_buffer(cx: &mut TestAppContext) {
2693 // Regression test for ZED-5R2: when the buffer is edited after the diff is
2694 // computed but before staging, anchor positions shift while diff_base_byte_range
2695 // values don't. If the primary (HEAD) hunk extends past the unstaged (index)
2696 // hunk, an edit in the extension region shifts the primary hunk end without
2697 // shifting the unstaged hunk end. The overshoot calculation then produces an
2698 // index_end that exceeds index_text.len().
2699 //
2700 // Setup:
2701 // HEAD: "aaa\nbbb\nccc\n" (primary hunk covers lines 1-2)
2702 // Index: "aaa\nbbb\nCCC\n" (unstaged hunk covers line 1 only)
2703 // Buffer: "aaa\nBBB\nCCC\n" (both lines differ from HEAD)
2704 //
2705 // The primary hunk spans buffer offsets 4..12, but the unstaged hunk only
2706 // spans 4..8. The pending hunk extends 4 bytes past the unstaged hunk.
2707 // An edit at offset 9 (inside "CCC") shifts the primary hunk end from 12
2708 // to 13 but leaves the unstaged hunk end at 8, making index_end = 13 > 12.
2709 let head_text = "aaa\nbbb\nccc\n";
2710 let index_text = "aaa\nbbb\nCCC\n";
2711 let buffer_text = "aaa\nBBB\nCCC\n";
2712
2713 let mut buffer = Buffer::new(
2714 ReplicaId::LOCAL,
2715 BufferId::new(1).unwrap(),
2716 buffer_text.to_string(),
2717 );
2718
2719 let unstaged_diff = cx.new(|cx| BufferDiff::new_with_base_text(index_text, &buffer, cx));
2720 let uncommitted_diff = cx.new(|cx| {
2721 let mut diff = BufferDiff::new_with_base_text(head_text, &buffer, cx);
2722 diff.set_secondary_diff(unstaged_diff);
2723 diff
2724 });
2725
2726 // Edit the buffer in the region between the unstaged hunk end (offset 8)
2727 // and the primary hunk end (offset 12). This shifts the primary hunk end
2728 // but not the unstaged hunk end.
2729 buffer.edit([(9..9, "Z")]);
2730
2731 uncommitted_diff.update(cx, |diff, cx| {
2732 diff.stage_or_unstage_all_hunks(true, &buffer, true, cx);
2733 });
2734 }
2735
2736 #[gpui::test]
2737 async fn test_toggling_stage_and_unstage_same_hunk(cx: &mut TestAppContext) {
2738 let head_text = "
2739 one
2740 two
2741 three
2742 "
2743 .unindent();
2744 let index_text = head_text.clone();
2745 let buffer_text = "
2746 one
2747 three
2748 "
2749 .unindent();
2750
2751 let buffer = Buffer::new(
2752 ReplicaId::LOCAL,
2753 BufferId::new(1).unwrap(),
2754 buffer_text.clone(),
2755 );
2756 let unstaged_diff = cx.new(|cx| BufferDiff::new_with_base_text(&index_text, &buffer, cx));
2757 let uncommitted_diff = cx.new(|cx| {
2758 let mut diff = BufferDiff::new_with_base_text(&head_text, &buffer, cx);
2759 diff.set_secondary_diff(unstaged_diff.clone());
2760 diff
2761 });
2762
2763 uncommitted_diff.update(cx, |diff, cx| {
2764 let hunk = diff.snapshot(cx).hunks(&buffer).next().unwrap();
2765
2766 let new_index_text = diff
2767 .stage_or_unstage_hunks(true, std::slice::from_ref(&hunk), &buffer, true, cx)
2768 .unwrap()
2769 .to_string();
2770 assert_eq!(new_index_text, buffer_text);
2771
2772 let hunk = diff.snapshot(cx).hunks(&buffer).next().unwrap();
2773 assert_eq!(
2774 hunk.secondary_status,
2775 DiffHunkSecondaryStatus::SecondaryHunkRemovalPending
2776 );
2777
2778 let index_text = diff
2779 .stage_or_unstage_hunks(false, &[hunk], &buffer, true, cx)
2780 .unwrap()
2781 .to_string();
2782 assert_eq!(index_text, head_text);
2783
2784 let hunk = diff.snapshot(cx).hunks(&buffer).next().unwrap();
2785 // optimistically unstaged (fine, could also be HasSecondaryHunk)
2786 assert_eq!(
2787 hunk.secondary_status,
2788 DiffHunkSecondaryStatus::SecondaryHunkAdditionPending
2789 );
2790 });
2791 }
2792
2793 #[gpui::test]
2794 async fn test_buffer_diff_compare(cx: &mut TestAppContext) {
2795 let base_text = "
2796 zero
2797 one
2798 two
2799 three
2800 four
2801 five
2802 six
2803 seven
2804 eight
2805 nine
2806 "
2807 .unindent();
2808
2809 let buffer_text_1 = "
2810 one
2811 three
2812 four
2813 five
2814 SIX
2815 seven
2816 eight
2817 NINE
2818 "
2819 .unindent();
2820
2821 let mut buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text_1);
2822
2823 let empty_diff = cx.update(|cx| BufferDiff::new(&buffer, cx).snapshot(cx));
2824 let diff_1 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2825 let DiffChanged {
2826 changed_range,
2827 base_text_changed_range,
2828 extended_range: _,
2829 } = compare_hunks(
2830 &diff_1.inner.hunks,
2831 &empty_diff.inner.hunks,
2832 &buffer,
2833 &buffer,
2834 &diff_1.base_text(),
2835 &diff_1.base_text(),
2836 );
2837 let range = changed_range.unwrap();
2838 assert_eq!(range.to_point(&buffer), Point::new(0, 0)..Point::new(8, 0));
2839 let base_text_range = base_text_changed_range.unwrap();
2840 assert_eq!(
2841 base_text_range.to_point(diff_1.base_text()),
2842 Point::new(0, 0)..Point::new(10, 0)
2843 );
2844
2845 // Edit does affects the diff because it recalculates word diffs.
2846 buffer.edit_via_marked_text(
2847 &"
2848 one
2849 three
2850 four
2851 five
2852 «SIX.5»
2853 seven
2854 eight
2855 NINE
2856 "
2857 .unindent(),
2858 );
2859 let diff_2 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2860 let DiffChanged {
2861 changed_range,
2862 base_text_changed_range,
2863 extended_range: _,
2864 } = compare_hunks(
2865 &diff_2.inner.hunks,
2866 &diff_1.inner.hunks,
2867 &buffer,
2868 &buffer,
2869 diff_2.base_text(),
2870 diff_2.base_text(),
2871 );
2872 assert_eq!(
2873 changed_range.unwrap().to_point(&buffer),
2874 Point::new(4, 0)..Point::new(5, 0),
2875 );
2876 assert_eq!(
2877 base_text_changed_range
2878 .unwrap()
2879 .to_point(diff_2.base_text()),
2880 Point::new(6, 0)..Point::new(7, 0),
2881 );
2882
2883 // Edit turns a deletion hunk into a modification.
2884 buffer.edit_via_marked_text(
2885 &"
2886 one
2887 «THREE»
2888 four
2889 five
2890 SIX.5
2891 seven
2892 eight
2893 NINE
2894 "
2895 .unindent(),
2896 );
2897 let diff_3 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2898 let DiffChanged {
2899 changed_range,
2900 base_text_changed_range,
2901 extended_range: _,
2902 } = compare_hunks(
2903 &diff_3.inner.hunks,
2904 &diff_2.inner.hunks,
2905 &buffer,
2906 &buffer,
2907 diff_3.base_text(),
2908 diff_3.base_text(),
2909 );
2910 let range = changed_range.unwrap();
2911 assert_eq!(range.to_point(&buffer), Point::new(1, 0)..Point::new(2, 0));
2912 let base_text_range = base_text_changed_range.unwrap();
2913 assert_eq!(
2914 base_text_range.to_point(diff_3.base_text()),
2915 Point::new(2, 0)..Point::new(4, 0)
2916 );
2917
2918 // Edit turns a modification hunk into a deletion.
2919 buffer.edit_via_marked_text(
2920 &"
2921 one
2922 THREE
2923 four
2924 five«»
2925 seven
2926 eight
2927 NINE
2928 "
2929 .unindent(),
2930 );
2931 let diff_4 = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
2932 let DiffChanged {
2933 changed_range,
2934 base_text_changed_range,
2935 extended_range: _,
2936 } = compare_hunks(
2937 &diff_4.inner.hunks,
2938 &diff_3.inner.hunks,
2939 &buffer,
2940 &buffer,
2941 diff_4.base_text(),
2942 diff_4.base_text(),
2943 );
2944 let range = changed_range.unwrap();
2945 assert_eq!(range.to_point(&buffer), Point::new(3, 4)..Point::new(4, 0));
2946 let base_text_range = base_text_changed_range.unwrap();
2947 assert_eq!(
2948 base_text_range.to_point(diff_4.base_text()),
2949 Point::new(6, 0)..Point::new(7, 0)
2950 );
2951
2952 // Edit introduces a new insertion hunk.
2953 buffer.edit_via_marked_text(
2954 &"
2955 one
2956 THREE
2957 four«
2958 FOUR.5
2959 »five
2960 seven
2961 eight
2962 NINE
2963 "
2964 .unindent(),
2965 );
2966 let diff_5 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text.clone(), cx);
2967 let DiffChanged {
2968 changed_range,
2969 base_text_changed_range,
2970 extended_range: _,
2971 } = compare_hunks(
2972 &diff_5.inner.hunks,
2973 &diff_4.inner.hunks,
2974 &buffer,
2975 &buffer,
2976 diff_5.base_text(),
2977 diff_5.base_text(),
2978 );
2979 let range = changed_range.unwrap();
2980 assert_eq!(range.to_point(&buffer), Point::new(3, 0)..Point::new(4, 0));
2981 let base_text_range = base_text_changed_range.unwrap();
2982 assert_eq!(
2983 base_text_range.to_point(diff_5.base_text()),
2984 Point::new(5, 0)..Point::new(5, 0)
2985 );
2986
2987 // Edit removes a hunk.
2988 buffer.edit_via_marked_text(
2989 &"
2990 one
2991 THREE
2992 four
2993 FOUR.5
2994 five
2995 seven
2996 eight
2997 «nine»
2998 "
2999 .unindent(),
3000 );
3001 let diff_6 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text.clone(), cx);
3002 let DiffChanged {
3003 changed_range,
3004 base_text_changed_range,
3005 extended_range: _,
3006 } = compare_hunks(
3007 &diff_6.inner.hunks,
3008 &diff_5.inner.hunks,
3009 &buffer,
3010 &buffer,
3011 diff_6.base_text(),
3012 diff_6.base_text(),
3013 );
3014 let range = changed_range.unwrap();
3015 assert_eq!(range.to_point(&buffer), Point::new(7, 0)..Point::new(8, 0));
3016 let base_text_range = base_text_changed_range.unwrap();
3017 assert_eq!(
3018 base_text_range.to_point(diff_6.base_text()),
3019 Point::new(9, 0)..Point::new(10, 0)
3020 );
3021
3022 buffer.edit_via_marked_text(
3023 &"
3024 one
3025 THREE
3026 four«»
3027 five
3028 seven
3029 eight
3030 «NINE»
3031 "
3032 .unindent(),
3033 );
3034
3035 let diff_7 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text.clone(), cx);
3036 let DiffChanged {
3037 changed_range,
3038 base_text_changed_range,
3039 extended_range: _,
3040 } = compare_hunks(
3041 &diff_7.inner.hunks,
3042 &diff_6.inner.hunks,
3043 &buffer,
3044 &buffer,
3045 diff_7.base_text(),
3046 diff_7.base_text(),
3047 );
3048 let range = changed_range.unwrap();
3049 assert_eq!(range.to_point(&buffer), Point::new(2, 4)..Point::new(7, 0));
3050 let base_text_range = base_text_changed_range.unwrap();
3051 assert_eq!(
3052 base_text_range.to_point(diff_7.base_text()),
3053 Point::new(5, 0)..Point::new(10, 0)
3054 );
3055
3056 buffer.edit_via_marked_text(
3057 &"
3058 one
3059 THREE
3060 four
3061 five«»seven
3062 eight
3063 NINE
3064 "
3065 .unindent(),
3066 );
3067
3068 let diff_8 = BufferDiffSnapshot::new_sync(buffer.snapshot(), base_text, cx);
3069 let DiffChanged {
3070 changed_range,
3071 base_text_changed_range,
3072 extended_range: _,
3073 } = compare_hunks(
3074 &diff_8.inner.hunks,
3075 &diff_7.inner.hunks,
3076 &buffer,
3077 &buffer,
3078 diff_8.base_text(),
3079 diff_8.base_text(),
3080 );
3081 let range = changed_range.unwrap();
3082 assert_eq!(range.to_point(&buffer), Point::new(3, 0)..Point::new(3, 4));
3083 let base_text_range = base_text_changed_range.unwrap();
3084 assert_eq!(
3085 base_text_range.to_point(diff_8.base_text()),
3086 Point::new(5, 0)..Point::new(8, 0)
3087 );
3088 }
3089
3090 #[gpui::test(iterations = 100)]
3091 async fn test_staging_and_unstaging_hunks(cx: &mut TestAppContext, mut rng: StdRng) {
3092 fn gen_line(rng: &mut StdRng) -> String {
3093 if rng.random_bool(0.2) {
3094 "\n".to_owned()
3095 } else {
3096 let c = rng.random_range('A'..='Z');
3097 format!("{c}{c}{c}\n")
3098 }
3099 }
3100
3101 fn gen_working_copy(rng: &mut StdRng, head: &str) -> String {
3102 let mut old_lines = {
3103 let mut old_lines = Vec::new();
3104 let old_lines_iter = head.lines();
3105 for line in old_lines_iter {
3106 assert!(!line.ends_with("\n"));
3107 old_lines.push(line.to_owned());
3108 }
3109 if old_lines.last().is_some_and(|line| line.is_empty()) {
3110 old_lines.pop();
3111 }
3112 old_lines.into_iter()
3113 };
3114 let mut result = String::new();
3115 let unchanged_count = rng.random_range(0..=old_lines.len());
3116 result +=
3117 &old_lines
3118 .by_ref()
3119 .take(unchanged_count)
3120 .fold(String::new(), |mut s, line| {
3121 writeln!(&mut s, "{line}").unwrap();
3122 s
3123 });
3124 while old_lines.len() > 0 {
3125 let deleted_count = rng.random_range(0..=old_lines.len());
3126 let _advance = old_lines
3127 .by_ref()
3128 .take(deleted_count)
3129 .map(|line| line.len() + 1)
3130 .sum::<usize>();
3131 let minimum_added = if deleted_count == 0 { 1 } else { 0 };
3132 let added_count = rng.random_range(minimum_added..=5);
3133 let addition = (0..added_count).map(|_| gen_line(rng)).collect::<String>();
3134 result += &addition;
3135
3136 if old_lines.len() > 0 {
3137 let blank_lines = old_lines.clone().take_while(|line| line.is_empty()).count();
3138 if blank_lines == old_lines.len() {
3139 break;
3140 };
3141 let unchanged_count =
3142 rng.random_range((blank_lines + 1).max(1)..=old_lines.len());
3143 result += &old_lines.by_ref().take(unchanged_count).fold(
3144 String::new(),
3145 |mut s, line| {
3146 writeln!(&mut s, "{line}").unwrap();
3147 s
3148 },
3149 );
3150 }
3151 }
3152 result
3153 }
3154
3155 fn uncommitted_diff(
3156 working_copy: &language::BufferSnapshot,
3157 index_text: &Rope,
3158 head_text: String,
3159 cx: &mut TestAppContext,
3160 ) -> Entity<BufferDiff> {
3161 let secondary = cx.new(|cx| {
3162 BufferDiff::new_with_base_text(&index_text.to_string(), &working_copy.text, cx)
3163 });
3164 cx.new(|cx| {
3165 let mut diff = BufferDiff::new_with_base_text(&head_text, &working_copy.text, cx);
3166 diff.secondary_diff = Some(secondary);
3167 diff
3168 })
3169 }
3170
3171 let operations = std::env::var("OPERATIONS")
3172 .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
3173 .unwrap_or(10);
3174
3175 let rng = &mut rng;
3176 let head_text = ('a'..='z').fold(String::new(), |mut s, c| {
3177 writeln!(&mut s, "{c}{c}{c}").unwrap();
3178 s
3179 });
3180 let working_copy = gen_working_copy(rng, &head_text);
3181 let working_copy = cx.new(|cx| {
3182 language::Buffer::local_normalized(
3183 Rope::from(working_copy.as_str()),
3184 text::LineEnding::default(),
3185 cx,
3186 )
3187 });
3188 let working_copy = working_copy.read_with(cx, |working_copy, _| working_copy.snapshot());
3189 let mut index_text = if rng.random() {
3190 Rope::from(head_text.as_str())
3191 } else {
3192 working_copy.as_rope().clone()
3193 };
3194
3195 let mut diff = uncommitted_diff(&working_copy, &index_text, head_text.clone(), cx);
3196 let mut hunks = diff.update(cx, |diff, cx| {
3197 diff.snapshot(cx)
3198 .hunks_intersecting_range(
3199 Anchor::min_max_range_for_buffer(diff.buffer_id),
3200 &working_copy,
3201 )
3202 .collect::<Vec<_>>()
3203 });
3204 if hunks.is_empty() {
3205 return;
3206 }
3207
3208 for _ in 0..operations {
3209 let i = rng.random_range(0..hunks.len());
3210 let hunk = &mut hunks[i];
3211 let hunk_to_change = hunk.clone();
3212 let stage = match hunk.secondary_status {
3213 DiffHunkSecondaryStatus::HasSecondaryHunk => {
3214 hunk.secondary_status = DiffHunkSecondaryStatus::NoSecondaryHunk;
3215 true
3216 }
3217 DiffHunkSecondaryStatus::NoSecondaryHunk => {
3218 hunk.secondary_status = DiffHunkSecondaryStatus::HasSecondaryHunk;
3219 false
3220 }
3221 _ => unreachable!(),
3222 };
3223
3224 index_text = diff.update(cx, |diff, cx| {
3225 diff.stage_or_unstage_hunks(stage, &[hunk_to_change], &working_copy, true, cx)
3226 .unwrap()
3227 });
3228
3229 diff = uncommitted_diff(&working_copy, &index_text, head_text.clone(), cx);
3230 let found_hunks = diff.update(cx, |diff, cx| {
3231 diff.snapshot(cx)
3232 .hunks_intersecting_range(
3233 Anchor::min_max_range_for_buffer(diff.buffer_id),
3234 &working_copy,
3235 )
3236 .collect::<Vec<_>>()
3237 });
3238 assert_eq!(hunks.len(), found_hunks.len());
3239
3240 for (expected_hunk, found_hunk) in hunks.iter().zip(&found_hunks) {
3241 assert_eq!(
3242 expected_hunk.buffer_range.to_point(&working_copy),
3243 found_hunk.buffer_range.to_point(&working_copy)
3244 );
3245 assert_eq!(
3246 expected_hunk.diff_base_byte_range,
3247 found_hunk.diff_base_byte_range
3248 );
3249 assert_eq!(expected_hunk.secondary_status, found_hunk.secondary_status);
3250 }
3251 hunks = found_hunks;
3252 }
3253 }
3254
3255 #[gpui::test]
3256 async fn test_changed_ranges(cx: &mut gpui::TestAppContext) {
3257 let base_text = "
3258 one
3259 two
3260 three
3261 four
3262 five
3263 six
3264 "
3265 .unindent();
3266 let buffer_text = "
3267 one
3268 TWO
3269 three
3270 four
3271 FIVE
3272 six
3273 "
3274 .unindent();
3275 let buffer = cx.new(|cx| language::Buffer::local(buffer_text, cx));
3276 let diff = cx.new(|cx| {
3277 BufferDiff::new_with_base_text(&base_text, &buffer.read(cx).text_snapshot(), cx)
3278 });
3279 cx.run_until_parked();
3280 let (tx, rx) = mpsc::channel();
3281 let subscription =
3282 cx.update(|cx| cx.subscribe(&diff, move |_, event, _| tx.send(event.clone()).unwrap()));
3283
3284 let snapshot = buffer.update(cx, |buffer, cx| {
3285 buffer.set_text(
3286 "
3287 ONE
3288 TWO
3289 THREE
3290 FOUR
3291 FIVE
3292 SIX
3293 "
3294 .unindent(),
3295 cx,
3296 );
3297 buffer.text_snapshot()
3298 });
3299 let update = diff
3300 .update(cx, |diff, cx| {
3301 diff.update_diff(
3302 snapshot.clone(),
3303 Some(base_text.as_str().into()),
3304 None,
3305 None,
3306 cx,
3307 )
3308 })
3309 .await;
3310 diff.update(cx, |diff, cx| diff.set_snapshot(update, &snapshot, cx))
3311 .await;
3312 cx.run_until_parked();
3313 drop(subscription);
3314 let events = rx.into_iter().collect::<Vec<_>>();
3315 match events.as_slice() {
3316 [
3317 BufferDiffEvent::DiffChanged(DiffChanged {
3318 changed_range: _,
3319 base_text_changed_range,
3320 extended_range: _,
3321 }),
3322 ] => {
3323 // TODO(cole) this seems like it should pass but currently fails (see compare_hunks)
3324 // assert_eq!(
3325 // *changed_range,
3326 // Some(Anchor::min_max_range_for_buffer(
3327 // buffer.read_with(cx, |buffer, _| buffer.remote_id())
3328 // ))
3329 // );
3330 assert_eq!(*base_text_changed_range, Some(0..base_text.len()));
3331 }
3332 _ => panic!("unexpected events: {:?}", events),
3333 }
3334 }
3335
3336 #[gpui::test]
3337 async fn test_extended_range(cx: &mut TestAppContext) {
3338 let base_text = "
3339 aaa
3340 bbb
3341
3342
3343
3344
3345
3346 ccc
3347 ddd
3348 "
3349 .unindent();
3350
3351 let buffer_text = "
3352 aaa
3353 bbb
3354
3355
3356
3357
3358
3359 CCC
3360 ddd
3361 "
3362 .unindent();
3363
3364 let mut buffer = Buffer::new(ReplicaId::LOCAL, BufferId::new(1).unwrap(), buffer_text);
3365 let old_buffer = buffer.snapshot().clone();
3366 let diff_a = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
3367
3368 buffer.edit([(Point::new(1, 3)..Point::new(1, 3), "\n")]);
3369 let diff_b = BufferDiffSnapshot::new_sync(&buffer, base_text, cx);
3370
3371 let DiffChanged {
3372 changed_range,
3373 base_text_changed_range: _,
3374 extended_range,
3375 } = compare_hunks(
3376 &diff_b.inner.hunks,
3377 &diff_a.inner.hunks,
3378 &old_buffer,
3379 &buffer,
3380 &diff_a.base_text(),
3381 &diff_a.base_text(),
3382 );
3383
3384 let changed_range = changed_range.unwrap();
3385 assert_eq!(
3386 changed_range.to_point(&buffer),
3387 Point::new(7, 0)..Point::new(9, 0),
3388 "changed_range should span from old hunk position to new hunk end"
3389 );
3390
3391 let extended_range = extended_range.unwrap();
3392 assert_eq!(
3393 extended_range.start.to_point(&buffer),
3394 Point::new(1, 3),
3395 "extended_range.start should extend to include the edit outside changed_range"
3396 );
3397 assert_eq!(
3398 extended_range.end.to_point(&buffer),
3399 Point::new(9, 0),
3400 "extended_range.end should collapse to changed_range.end when no edits in end margin"
3401 );
3402
3403 let base_text_2 = "
3404 one
3405 two
3406 three
3407 four
3408 five
3409 six
3410 seven
3411 eight
3412 "
3413 .unindent();
3414
3415 let buffer_text_2 = "
3416 ONE
3417 two
3418 THREE
3419 four
3420 FIVE
3421 six
3422 SEVEN
3423 eight
3424 "
3425 .unindent();
3426
3427 let mut buffer_2 = Buffer::new(ReplicaId::LOCAL, BufferId::new(2).unwrap(), buffer_text_2);
3428 let old_buffer_2 = buffer_2.snapshot().clone();
3429 let diff_2a = BufferDiffSnapshot::new_sync(&buffer_2, base_text_2.clone(), cx);
3430
3431 buffer_2.edit([(Point::new(4, 0)..Point::new(4, 4), "FIVE_CHANGED")]);
3432 let diff_2b = BufferDiffSnapshot::new_sync(&buffer_2, base_text_2, cx);
3433
3434 let DiffChanged {
3435 changed_range,
3436 base_text_changed_range: _,
3437 extended_range,
3438 } = compare_hunks(
3439 &diff_2b.inner.hunks,
3440 &diff_2a.inner.hunks,
3441 &old_buffer_2,
3442 &buffer_2,
3443 &diff_2a.base_text(),
3444 &diff_2a.base_text(),
3445 );
3446
3447 let changed_range = changed_range.unwrap();
3448 assert_eq!(
3449 changed_range.to_point(&buffer_2),
3450 Point::new(4, 0)..Point::new(5, 0),
3451 "changed_range should be just the hunk that changed (FIVE)"
3452 );
3453
3454 let extended_range = extended_range.unwrap();
3455 assert_eq!(
3456 extended_range.to_point(&buffer_2),
3457 Point::new(4, 0)..Point::new(5, 0),
3458 "extended_range should equal changed_range when edit is within the hunk"
3459 );
3460 }
3461
3462 #[gpui::test]
3463 async fn test_buffer_diff_compare_with_base_text_change(_cx: &mut TestAppContext) {
3464 // Use a shared base text buffer so that anchors from old and new snapshots
3465 // share the same remote_id and resolve correctly across versions.
3466 let initial_base = "aaa\nbbb\nccc\nddd\neee\n";
3467 let mut base_text_buffer = Buffer::new(
3468 ReplicaId::LOCAL,
3469 BufferId::new(99).unwrap(),
3470 initial_base.to_string(),
3471 );
3472
3473 // --- Scenario 1: Base text gains a line, producing a new deletion hunk ---
3474 //
3475 // Buffer has a modification (ccc → CCC). When the base text gains
3476 // a new line "XXX" after "aaa", the diff now also contains a
3477 // deletion for that line, and the modification hunk shifts in the
3478 // base text.
3479 let buffer_text_1 = "aaa\nbbb\nCCC\nddd\neee\n";
3480 let buffer = Buffer::new(
3481 ReplicaId::LOCAL,
3482 BufferId::new(1).unwrap(),
3483 buffer_text_1.to_string(),
3484 );
3485
3486 let old_base_snapshot_1 = base_text_buffer.snapshot().clone();
3487 let old_hunks_1 = compute_hunks(
3488 Some((Arc::from(initial_base), Rope::from(initial_base))),
3489 buffer.snapshot(),
3490 None,
3491 );
3492
3493 // Insert "XXX\n" after "aaa\n" in the base text.
3494 base_text_buffer.edit([(4..4, "XXX\n")]);
3495 let new_base_str_1: Arc<str> = Arc::from(base_text_buffer.text().as_str());
3496 let new_base_snapshot_1 = base_text_buffer.snapshot();
3497
3498 let new_hunks_1 = compute_hunks(
3499 Some((new_base_str_1.clone(), Rope::from(new_base_str_1.as_ref()))),
3500 buffer.snapshot(),
3501 None,
3502 );
3503
3504 let DiffChanged {
3505 changed_range,
3506 base_text_changed_range,
3507 extended_range: _,
3508 } = compare_hunks(
3509 &new_hunks_1,
3510 &old_hunks_1,
3511 &buffer.snapshot(),
3512 &buffer.snapshot(),
3513 &old_base_snapshot_1,
3514 &new_base_snapshot_1,
3515 );
3516
3517 // The new deletion hunk (XXX) starts at buffer row 1 and the
3518 // modification hunk (ccc → CCC) now has a different
3519 // diff_base_byte_range, so the changed range spans both.
3520 let range = changed_range.unwrap();
3521 assert_eq!(range.to_point(&buffer), Point::new(1, 0)..Point::new(3, 0),);
3522 let base_range = base_text_changed_range.unwrap();
3523 assert_eq!(
3524 base_range.to_point(&new_base_snapshot_1),
3525 Point::new(1, 0)..Point::new(4, 0),
3526 );
3527
3528 // --- Scenario 2: Base text changes to match the buffer (hunk disappears) ---
3529 //
3530 // Start fresh with a simple base text.
3531 let simple_base = "one\ntwo\nthree\n";
3532 let mut base_buf_2 = Buffer::new(
3533 ReplicaId::LOCAL,
3534 BufferId::new(100).unwrap(),
3535 simple_base.to_string(),
3536 );
3537
3538 let buffer_text_2 = "one\nTWO\nthree\n";
3539 let buffer_2 = Buffer::new(
3540 ReplicaId::LOCAL,
3541 BufferId::new(2).unwrap(),
3542 buffer_text_2.to_string(),
3543 );
3544
3545 let old_base_snapshot_2 = base_buf_2.snapshot().clone();
3546 let old_hunks_2 = compute_hunks(
3547 Some((Arc::from(simple_base), Rope::from(simple_base))),
3548 buffer_2.snapshot(),
3549 None,
3550 );
3551
3552 // The base text is edited so "two" becomes "TWO", now matching the buffer.
3553 base_buf_2.edit([(4..7, "TWO")]);
3554 let new_base_str_2: Arc<str> = Arc::from(base_buf_2.text().as_str());
3555 let new_base_snapshot_2 = base_buf_2.snapshot();
3556
3557 let new_hunks_2 = compute_hunks(
3558 Some((new_base_str_2.clone(), Rope::from(new_base_str_2.as_ref()))),
3559 buffer_2.snapshot(),
3560 None,
3561 );
3562
3563 let DiffChanged {
3564 changed_range,
3565 base_text_changed_range,
3566 extended_range: _,
3567 } = compare_hunks(
3568 &new_hunks_2,
3569 &old_hunks_2,
3570 &buffer_2.snapshot(),
3571 &buffer_2.snapshot(),
3572 &old_base_snapshot_2,
3573 &new_base_snapshot_2,
3574 );
3575
3576 // The old modification hunk (two → TWO) is now gone because the
3577 // base text matches the buffer. The changed range covers where the
3578 // old hunk used to be.
3579 let range = changed_range.unwrap();
3580 assert_eq!(
3581 range.to_point(&buffer_2),
3582 Point::new(1, 0)..Point::new(2, 0),
3583 );
3584 let base_range = base_text_changed_range.unwrap();
3585 // The old hunk's diff_base_byte_range covered "two\n" (bytes 4..8).
3586 // anchor_after(4) is right-biased at the start of the deleted "two",
3587 // so after the edit replacing "two" with "TWO" it resolves past the
3588 // insertion to Point(1, 3).
3589 assert_eq!(
3590 base_range.to_point(&new_base_snapshot_2),
3591 Point::new(1, 3)..Point::new(2, 0),
3592 );
3593
3594 // --- Scenario 3: Base text edit changes one hunk but not another ---
3595 //
3596 // Two modification hunks exist. Only one of them is resolved by
3597 // the base text change; the other remains identical.
3598 let base_3 = "aaa\nbbb\nccc\nddd\neee\n";
3599 let mut base_buf_3 = Buffer::new(
3600 ReplicaId::LOCAL,
3601 BufferId::new(101).unwrap(),
3602 base_3.to_string(),
3603 );
3604
3605 let buffer_text_3 = "aaa\nBBB\nccc\nDDD\neee\n";
3606 let buffer_3 = Buffer::new(
3607 ReplicaId::LOCAL,
3608 BufferId::new(3).unwrap(),
3609 buffer_text_3.to_string(),
3610 );
3611
3612 let old_base_snapshot_3 = base_buf_3.snapshot().clone();
3613 let old_hunks_3 = compute_hunks(
3614 Some((Arc::from(base_3), Rope::from(base_3))),
3615 buffer_3.snapshot(),
3616 None,
3617 );
3618
3619 // Change "ddd" to "DDD" in the base text so that hunk disappears,
3620 // but "bbb" stays, so its hunk remains.
3621 base_buf_3.edit([(12..15, "DDD")]);
3622 let new_base_str_3: Arc<str> = Arc::from(base_buf_3.text().as_str());
3623 let new_base_snapshot_3 = base_buf_3.snapshot();
3624
3625 let new_hunks_3 = compute_hunks(
3626 Some((new_base_str_3.clone(), Rope::from(new_base_str_3.as_ref()))),
3627 buffer_3.snapshot(),
3628 None,
3629 );
3630
3631 let DiffChanged {
3632 changed_range,
3633 base_text_changed_range,
3634 extended_range: _,
3635 } = compare_hunks(
3636 &new_hunks_3,
3637 &old_hunks_3,
3638 &buffer_3.snapshot(),
3639 &buffer_3.snapshot(),
3640 &old_base_snapshot_3,
3641 &new_base_snapshot_3,
3642 );
3643
3644 // Only the second hunk (ddd → DDD) disappeared; the first hunk
3645 // (bbb → BBB) is unchanged, so the changed range covers only line 3.
3646 let range = changed_range.unwrap();
3647 assert_eq!(
3648 range.to_point(&buffer_3),
3649 Point::new(3, 0)..Point::new(4, 0),
3650 );
3651 let base_range = base_text_changed_range.unwrap();
3652 // anchor_after(12) is right-biased at the start of deleted "ddd",
3653 // so after the edit replacing "ddd" with "DDD" it resolves past
3654 // the insertion to Point(3, 3).
3655 assert_eq!(
3656 base_range.to_point(&new_base_snapshot_3),
3657 Point::new(3, 3)..Point::new(4, 0),
3658 );
3659
3660 // --- Scenario 4: Both buffer and base text change simultaneously ---
3661 //
3662 // The buffer gains an edit that introduces a new hunk while the
3663 // base text also changes.
3664 let base_4 = "alpha\nbeta\ngamma\ndelta\n";
3665 let mut base_buf_4 = Buffer::new(
3666 ReplicaId::LOCAL,
3667 BufferId::new(102).unwrap(),
3668 base_4.to_string(),
3669 );
3670
3671 let buffer_text_4 = "alpha\nBETA\ngamma\ndelta\n";
3672 let mut buffer_4 = Buffer::new(
3673 ReplicaId::LOCAL,
3674 BufferId::new(4).unwrap(),
3675 buffer_text_4.to_string(),
3676 );
3677
3678 let old_base_snapshot_4 = base_buf_4.snapshot().clone();
3679 let old_buffer_snapshot_4 = buffer_4.snapshot().clone();
3680 let old_hunks_4 = compute_hunks(
3681 Some((Arc::from(base_4), Rope::from(base_4))),
3682 buffer_4.snapshot(),
3683 None,
3684 );
3685
3686 // Edit the buffer: change "delta" to "DELTA" (new modification hunk).
3687 buffer_4.edit_via_marked_text(
3688 &"
3689 alpha
3690 BETA
3691 gamma
3692 «DELTA»
3693 "
3694 .unindent(),
3695 );
3696
3697 // Edit the base text: change "beta" to "BETA" (resolves that hunk).
3698 base_buf_4.edit([(6..10, "BETA")]);
3699 let new_base_str_4: Arc<str> = Arc::from(base_buf_4.text().as_str());
3700 let new_base_snapshot_4 = base_buf_4.snapshot();
3701
3702 let new_hunks_4 = compute_hunks(
3703 Some((new_base_str_4.clone(), Rope::from(new_base_str_4.as_ref()))),
3704 buffer_4.snapshot(),
3705 None,
3706 );
3707
3708 let DiffChanged {
3709 changed_range,
3710 base_text_changed_range,
3711 extended_range: _,
3712 } = compare_hunks(
3713 &new_hunks_4,
3714 &old_hunks_4,
3715 &old_buffer_snapshot_4,
3716 &buffer_4.snapshot(),
3717 &old_base_snapshot_4,
3718 &new_base_snapshot_4,
3719 );
3720
3721 // The old BETA hunk (line 1) is gone and a new DELTA hunk (line 3)
3722 // appeared, so the changed range spans from line 1 through line 4.
3723 let range = changed_range.unwrap();
3724 assert_eq!(
3725 range.to_point(&buffer_4),
3726 Point::new(1, 0)..Point::new(4, 0),
3727 );
3728 let base_range = base_text_changed_range.unwrap();
3729 // The old BETA hunk's base range started at byte 6 ("beta"). After
3730 // the base text edit replacing "beta" with "BETA", anchor_after(6)
3731 // resolves past the insertion to Point(1, 4).
3732 assert_eq!(
3733 base_range.to_point(&new_base_snapshot_4),
3734 Point::new(1, 4)..Point::new(4, 0),
3735 );
3736 }
3737
3738 #[gpui::test(iterations = 100)]
3739 async fn test_patch_for_range_random(cx: &mut TestAppContext, mut rng: StdRng) {
3740 fn gen_line(rng: &mut StdRng) -> String {
3741 if rng.random_bool(0.2) {
3742 "\n".to_owned()
3743 } else {
3744 let c = rng.random_range('A'..='Z');
3745 format!("{c}{c}{c}\n")
3746 }
3747 }
3748
3749 fn gen_text(rng: &mut StdRng, line_count: usize) -> String {
3750 (0..line_count).map(|_| gen_line(rng)).collect()
3751 }
3752
3753 fn gen_edits_from(rng: &mut StdRng, base: &str) -> String {
3754 let mut old_lines: Vec<&str> = base.lines().collect();
3755 let mut result = String::new();
3756
3757 while !old_lines.is_empty() {
3758 let unchanged_count = rng.random_range(0..=old_lines.len());
3759 for _ in 0..unchanged_count {
3760 if old_lines.is_empty() {
3761 break;
3762 }
3763 result.push_str(old_lines.remove(0));
3764 result.push('\n');
3765 }
3766
3767 if old_lines.is_empty() {
3768 break;
3769 }
3770
3771 let deleted_count = rng.random_range(0..=old_lines.len().min(3));
3772 for _ in 0..deleted_count {
3773 if old_lines.is_empty() {
3774 break;
3775 }
3776 old_lines.remove(0);
3777 }
3778
3779 let minimum_added = if deleted_count == 0 { 1 } else { 0 };
3780 let added_count = rng.random_range(minimum_added..=3);
3781 for _ in 0..added_count {
3782 result.push_str(&gen_line(rng));
3783 }
3784 }
3785
3786 result
3787 }
3788
3789 fn random_point_in_text(rng: &mut StdRng, lines: &[&str]) -> Point {
3790 if lines.is_empty() {
3791 return Point::zero();
3792 }
3793 let row = rng.random_range(0..lines.len() as u32);
3794 let line = lines[row as usize];
3795 let col = if line.is_empty() {
3796 0
3797 } else {
3798 rng.random_range(0..=line.len() as u32)
3799 };
3800 Point::new(row, col)
3801 }
3802
3803 fn random_range_in_text(rng: &mut StdRng, lines: &[&str]) -> RangeInclusive<Point> {
3804 let start = random_point_in_text(rng, lines);
3805 let end = random_point_in_text(rng, lines);
3806 if start <= end {
3807 start..=end
3808 } else {
3809 end..=start
3810 }
3811 }
3812
3813 fn points_in_range(range: &RangeInclusive<Point>, lines: &[&str]) -> Vec<Point> {
3814 let mut points = Vec::new();
3815 for row in range.start().row..=range.end().row {
3816 if row as usize >= lines.len() {
3817 points.push(Point::new(row, 0));
3818 continue;
3819 }
3820 let line = lines[row as usize];
3821 let start_col = if row == range.start().row {
3822 range.start().column
3823 } else {
3824 0
3825 };
3826 let end_col = if row == range.end().row {
3827 range.end().column
3828 } else {
3829 line.len() as u32
3830 };
3831 for col in start_col..=end_col {
3832 points.push(Point::new(row, col));
3833 }
3834 }
3835 points
3836 }
3837
3838 let rng = &mut rng;
3839
3840 let line_count = rng.random_range(5..20);
3841 let base_text = gen_text(rng, line_count);
3842 let initial_buffer_text = gen_edits_from(rng, &base_text);
3843
3844 let mut buffer = Buffer::new(
3845 ReplicaId::LOCAL,
3846 BufferId::new(1).unwrap(),
3847 initial_buffer_text.clone(),
3848 );
3849
3850 let diff = BufferDiffSnapshot::new_sync(&buffer, base_text.clone(), cx);
3851
3852 let edit_count = rng.random_range(1..=5);
3853 for _ in 0..edit_count {
3854 let buffer_text = buffer.text();
3855 if buffer_text.is_empty() {
3856 buffer.edit([(0..0, gen_line(rng))]);
3857 } else {
3858 let lines: Vec<&str> = buffer_text.lines().collect();
3859 let start_row = rng.random_range(0..lines.len());
3860 let end_row = rng.random_range(start_row..=lines.len().min(start_row + 3));
3861
3862 let start_col = if start_row < lines.len() {
3863 rng.random_range(0..=lines[start_row].len())
3864 } else {
3865 0
3866 };
3867 let end_col = if end_row < lines.len() {
3868 rng.random_range(0..=lines[end_row].len())
3869 } else {
3870 0
3871 };
3872
3873 let start_offset = buffer
3874 .point_to_offset(Point::new(start_row as u32, start_col as u32))
3875 .min(buffer.len());
3876 let end_offset = buffer
3877 .point_to_offset(Point::new(end_row as u32, end_col as u32))
3878 .min(buffer.len());
3879
3880 let (start, end) = if start_offset <= end_offset {
3881 (start_offset, end_offset)
3882 } else {
3883 (end_offset, start_offset)
3884 };
3885
3886 let new_text = if rng.random_bool(0.3) {
3887 String::new()
3888 } else {
3889 let line_count = rng.random_range(0..=2);
3890 gen_text(rng, line_count)
3891 };
3892
3893 buffer.edit([(start..end, new_text)]);
3894 }
3895 }
3896
3897 let buffer_snapshot = buffer.snapshot();
3898
3899 let buffer_text = buffer_snapshot.text();
3900 let buffer_lines: Vec<&str> = buffer_text.lines().collect();
3901 let base_lines: Vec<&str> = base_text.lines().collect();
3902
3903 let test_count = 10;
3904 for _ in 0..test_count {
3905 let range = random_range_in_text(rng, &buffer_lines);
3906 let points = points_in_range(&range, &buffer_lines);
3907
3908 let optimized_patch = diff.patch_for_buffer_range(range.clone(), &buffer_snapshot);
3909 let naive_patch = diff.patch_for_buffer_range_naive(&buffer_snapshot);
3910
3911 for point in points {
3912 let optimized_edit = optimized_patch.edit_for_old_position(point);
3913 let naive_edit = naive_patch.edit_for_old_position(point);
3914
3915 assert_eq!(
3916 optimized_edit,
3917 naive_edit,
3918 "patch_for_buffer_range mismatch at point {:?} in range {:?}\nbase_text: {:?}\ninitial_buffer: {:?}\ncurrent_buffer: {:?}",
3919 point,
3920 range,
3921 base_text,
3922 initial_buffer_text,
3923 buffer_snapshot.text()
3924 );
3925 }
3926 }
3927
3928 for _ in 0..test_count {
3929 let range = random_range_in_text(rng, &base_lines);
3930 let points = points_in_range(&range, &base_lines);
3931
3932 let optimized_patch = diff.patch_for_base_text_range(range.clone(), &buffer_snapshot);
3933 let naive_patch = diff.patch_for_base_text_range_naive(&buffer_snapshot);
3934
3935 for point in points {
3936 let optimized_edit = optimized_patch.edit_for_old_position(point);
3937 let naive_edit = naive_patch.edit_for_old_position(point);
3938
3939 assert_eq!(
3940 optimized_edit,
3941 naive_edit,
3942 "patch_for_base_text_range mismatch at point {:?} in range {:?}\nbase_text: {:?}\ninitial_buffer: {:?}\ncurrent_buffer: {:?}",
3943 point,
3944 range,
3945 base_text,
3946 initial_buffer_text,
3947 buffer_snapshot.text()
3948 );
3949 }
3950 }
3951 }
3952}