1//! Movement module contains helper functions for calculating intended position
2//! in editor given a given motion (e.g. it handles converting a "move left" command into coordinates in editor). It is exposed mostly for use by vim crate.
3
4use super::{Bias, DisplayPoint, DisplaySnapshot, SelectionGoal, ToDisplayPoint};
5use crate::{DisplayRow, EditorStyle, ToOffset, ToPoint, scroll::ScrollAnchor};
6use gpui::{Pixels, WindowTextSystem};
7use language::{CharClassifier, Point};
8use multi_buffer::{MultiBufferRow, MultiBufferSnapshot};
9use serde::Deserialize;
10use workspace::searchable::Direction;
11
12use std::{ops::Range, sync::Arc};
13
14/// Defines search strategy for items in `movement` module.
15/// `FindRange::SingeLine` only looks for a match on a single line at a time, whereas
16/// `FindRange::MultiLine` keeps going until the end of a string.
17#[derive(Clone, Copy, Debug, PartialEq, Eq, Deserialize)]
18pub enum FindRange {
19 SingleLine,
20 MultiLine,
21}
22
23/// TextLayoutDetails encompasses everything we need to move vertically
24/// taking into account variable width characters.
25pub struct TextLayoutDetails {
26 pub(crate) text_system: Arc<WindowTextSystem>,
27 pub(crate) editor_style: EditorStyle,
28 pub(crate) rem_size: Pixels,
29 pub scroll_anchor: ScrollAnchor,
30 pub visible_rows: Option<f32>,
31 pub vertical_scroll_margin: f32,
32}
33
34/// Returns a column to the left of the current point, wrapping
35/// to the previous line if that point is at the start of line.
36pub fn left(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
37 if point.column() > 0 {
38 *point.column_mut() -= 1;
39 } else if point.row().0 > 0 {
40 *point.row_mut() -= 1;
41 *point.column_mut() = map.line_len(point.row());
42 }
43 map.clip_point(point, Bias::Left)
44}
45
46/// Returns a column to the left of the current point, doing nothing if
47/// that point is already at the start of line.
48pub fn saturating_left(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
49 if point.column() > 0 {
50 *point.column_mut() -= 1;
51 } else if point.column() == 0 {
52 // If the current sofr_wrap mode is used, the column corresponding to the display is 0,
53 // which does not necessarily mean that the actual beginning of a paragraph
54 if map.display_point_to_fold_point(point, Bias::Left).column() > 0 {
55 return left(map, point);
56 }
57 }
58 map.clip_point(point, Bias::Left)
59}
60
61/// Returns a column to the right of the current point, wrapping
62/// to the next line if that point is at the end of line.
63pub fn right(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
64 if point.column() < map.line_len(point.row()) {
65 *point.column_mut() += 1;
66 } else if point.row() < map.max_point().row() {
67 *point.row_mut() += 1;
68 *point.column_mut() = 0;
69 }
70 map.clip_point(point, Bias::Right)
71}
72
73/// Returns a column to the right of the current point, not performing any wrapping
74/// if that point is already at the end of line.
75pub fn saturating_right(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
76 *point.column_mut() += 1;
77 map.clip_point(point, Bias::Right)
78}
79
80/// Returns a display point for the preceding displayed line (which might be a soft-wrapped line).
81pub fn up(
82 map: &DisplaySnapshot,
83 start: DisplayPoint,
84 goal: SelectionGoal,
85 preserve_column_at_start: bool,
86 text_layout_details: &TextLayoutDetails,
87) -> (DisplayPoint, SelectionGoal) {
88 up_by_rows(
89 map,
90 start,
91 1,
92 goal,
93 preserve_column_at_start,
94 text_layout_details,
95 )
96}
97
98/// Returns a display point for the next displayed line (which might be a soft-wrapped line).
99pub fn down(
100 map: &DisplaySnapshot,
101 start: DisplayPoint,
102 goal: SelectionGoal,
103 preserve_column_at_end: bool,
104 text_layout_details: &TextLayoutDetails,
105) -> (DisplayPoint, SelectionGoal) {
106 down_by_rows(
107 map,
108 start,
109 1,
110 goal,
111 preserve_column_at_end,
112 text_layout_details,
113 )
114}
115
116pub(crate) fn up_by_rows(
117 map: &DisplaySnapshot,
118 start: DisplayPoint,
119 row_count: u32,
120 goal: SelectionGoal,
121 preserve_column_at_start: bool,
122 text_layout_details: &TextLayoutDetails,
123) -> (DisplayPoint, SelectionGoal) {
124 let goal_x = match goal {
125 SelectionGoal::HorizontalPosition(x) => x.into(),
126 SelectionGoal::WrappedHorizontalPosition((_, x)) => x.into(),
127 SelectionGoal::HorizontalRange { end, .. } => end.into(),
128 _ => map.x_for_display_point(start, text_layout_details),
129 };
130
131 let prev_row = DisplayRow(start.row().0.saturating_sub(row_count));
132 let mut point = map.clip_point(
133 DisplayPoint::new(prev_row, map.line_len(prev_row)),
134 Bias::Left,
135 );
136 if point.row() < start.row() {
137 *point.column_mut() = map.display_column_for_x(point.row(), goal_x, text_layout_details)
138 } else if preserve_column_at_start {
139 return (start, goal);
140 } else {
141 point = DisplayPoint::new(DisplayRow(0), 0);
142 }
143
144 let mut clipped_point = map.clip_point(point, Bias::Left);
145 if clipped_point.row() < point.row() {
146 clipped_point = map.clip_point(point, Bias::Right);
147 }
148 (
149 clipped_point,
150 SelectionGoal::HorizontalPosition(goal_x.into()),
151 )
152}
153
154pub(crate) fn down_by_rows(
155 map: &DisplaySnapshot,
156 start: DisplayPoint,
157 row_count: u32,
158 goal: SelectionGoal,
159 preserve_column_at_end: bool,
160 text_layout_details: &TextLayoutDetails,
161) -> (DisplayPoint, SelectionGoal) {
162 let goal_x = match goal {
163 SelectionGoal::HorizontalPosition(x) => x.into(),
164 SelectionGoal::WrappedHorizontalPosition((_, x)) => x.into(),
165 SelectionGoal::HorizontalRange { end, .. } => end.into(),
166 _ => map.x_for_display_point(start, text_layout_details),
167 };
168
169 let new_row = DisplayRow(start.row().0 + row_count);
170 let mut point = map.clip_point(DisplayPoint::new(new_row, 0), Bias::Right);
171 if point.row() > start.row() {
172 *point.column_mut() = map.display_column_for_x(point.row(), goal_x, text_layout_details)
173 } else if preserve_column_at_end {
174 return (start, goal);
175 } else {
176 point = map.max_point();
177 }
178
179 let mut clipped_point = map.clip_point(point, Bias::Right);
180 if clipped_point.row() > point.row() {
181 clipped_point = map.clip_point(point, Bias::Left);
182 }
183 (
184 clipped_point,
185 SelectionGoal::HorizontalPosition(goal_x.into()),
186 )
187}
188
189/// Returns a position of the start of line.
190/// If `stop_at_soft_boundaries` is true, the returned position is that of the
191/// displayed line (e.g. it could actually be in the middle of a text line if that line is soft-wrapped).
192/// Otherwise it's always going to be the start of a logical line.
193pub fn line_beginning(
194 map: &DisplaySnapshot,
195 display_point: DisplayPoint,
196 stop_at_soft_boundaries: bool,
197) -> DisplayPoint {
198 let point = display_point.to_point(map);
199 let soft_line_start = map.clip_point(DisplayPoint::new(display_point.row(), 0), Bias::Right);
200 let line_start = map.prev_line_boundary(point).1;
201
202 if stop_at_soft_boundaries && display_point != soft_line_start {
203 soft_line_start
204 } else {
205 line_start
206 }
207}
208
209/// Returns the last indented position on a given line.
210/// If `stop_at_soft_boundaries` is true, the returned [`DisplayPoint`] is that of a
211/// displayed line (e.g. if there's soft wrap it's gonna be returned),
212/// otherwise it's always going to be a start of a logical line.
213pub fn indented_line_beginning(
214 map: &DisplaySnapshot,
215 display_point: DisplayPoint,
216 stop_at_soft_boundaries: bool,
217 stop_at_indent: bool,
218) -> DisplayPoint {
219 let point = display_point.to_point(map);
220 let soft_line_start = map.clip_point(DisplayPoint::new(display_point.row(), 0), Bias::Right);
221 let indent_start = Point::new(
222 point.row,
223 map.buffer_snapshot
224 .indent_size_for_line(MultiBufferRow(point.row))
225 .len,
226 )
227 .to_display_point(map);
228 let line_start = map.prev_line_boundary(point).1;
229
230 if stop_at_soft_boundaries && soft_line_start > indent_start && display_point != soft_line_start
231 {
232 soft_line_start
233 } else if stop_at_indent && (display_point > indent_start || display_point == line_start) {
234 indent_start
235 } else {
236 line_start
237 }
238}
239
240/// Returns a position of the end of line.
241///
242/// If `stop_at_soft_boundaries` is true, the returned position is that of the
243/// displayed line (e.g. it could actually be in the middle of a text line if that line is soft-wrapped).
244/// Otherwise it's always going to be the end of a logical line.
245pub fn line_end(
246 map: &DisplaySnapshot,
247 display_point: DisplayPoint,
248 stop_at_soft_boundaries: bool,
249) -> DisplayPoint {
250 let soft_line_end = map.clip_point(
251 DisplayPoint::new(display_point.row(), map.line_len(display_point.row())),
252 Bias::Left,
253 );
254 if stop_at_soft_boundaries && display_point != soft_line_end {
255 soft_line_end
256 } else {
257 map.next_line_boundary(display_point.to_point(map)).1
258 }
259}
260
261/// Returns a position of the previous word boundary, where a word character is defined as either
262/// uppercase letter, lowercase letter, '_' character or language-specific word character (like '-' in CSS).
263pub fn previous_word_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
264 let raw_point = point.to_point(map);
265 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
266
267 let mut is_first_iteration = true;
268 find_preceding_boundary_display_point(map, point, FindRange::MultiLine, |left, right| {
269 // Make alt-left skip punctuation to respect VSCode behaviour. For example: hello.| goes to |hello.
270 if is_first_iteration
271 && classifier.is_punctuation(right)
272 && !classifier.is_punctuation(left)
273 && left != '\n'
274 {
275 is_first_iteration = false;
276 return false;
277 }
278 is_first_iteration = false;
279
280 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(right))
281 || left == '\n'
282 })
283}
284
285/// Returns a position of the previous word boundary, where a word character is defined as either
286/// uppercase letter, lowercase letter, '_' character, language-specific word character (like '-' in CSS) or newline.
287pub fn previous_word_start_or_newline(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
288 let raw_point = point.to_point(map);
289 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
290
291 find_preceding_boundary_display_point(map, point, FindRange::MultiLine, |left, right| {
292 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(right))
293 || left == '\n'
294 || right == '\n'
295 })
296}
297
298/// Text movements are too greedy, making deletions too greedy too.
299/// Makes deletions more ergonomic by potentially reducing the deletion range based on its text contents:
300/// * whitespace sequences with length >= 2 stop the deletion after removal (despite movement jumping over the word behind the whitespaces)
301/// * brackets stop the deletion after removal (despite movement currently not accounting for these and jumping over)
302pub fn adjust_greedy_deletion(
303 map: &DisplaySnapshot,
304 delete_from: DisplayPoint,
305 delete_until: DisplayPoint,
306 ignore_brackets: bool,
307) -> DisplayPoint {
308 if delete_from == delete_until {
309 return delete_until;
310 }
311 let is_backward = delete_from > delete_until;
312 let delete_range = if is_backward {
313 map.display_point_to_point(delete_until, Bias::Left)
314 .to_offset(&map.buffer_snapshot)
315 ..map
316 .display_point_to_point(delete_from, Bias::Right)
317 .to_offset(&map.buffer_snapshot)
318 } else {
319 map.display_point_to_point(delete_from, Bias::Left)
320 .to_offset(&map.buffer_snapshot)
321 ..map
322 .display_point_to_point(delete_until, Bias::Right)
323 .to_offset(&map.buffer_snapshot)
324 };
325
326 let trimmed_delete_range = if ignore_brackets {
327 delete_range
328 } else {
329 let brackets_in_delete_range = map
330 .buffer_snapshot
331 .bracket_ranges(delete_range.clone())
332 .into_iter()
333 .flatten()
334 .flat_map(|(left_bracket, right_bracket)| {
335 [
336 left_bracket.start,
337 left_bracket.end,
338 right_bracket.start,
339 right_bracket.end,
340 ]
341 })
342 .filter(|&bracket| delete_range.start < bracket && bracket < delete_range.end);
343 let closest_bracket = if is_backward {
344 brackets_in_delete_range.max()
345 } else {
346 brackets_in_delete_range.min()
347 };
348
349 if is_backward {
350 closest_bracket.unwrap_or(delete_range.start)..delete_range.end
351 } else {
352 delete_range.start..closest_bracket.unwrap_or(delete_range.end)
353 }
354 };
355
356 let mut whitespace_sequences = Vec::new();
357 let mut current_offset = trimmed_delete_range.start;
358 let mut whitespace_sequence_length = 0;
359 let mut whitespace_sequence_start = 0;
360 for ch in map
361 .buffer_snapshot
362 .text_for_range(trimmed_delete_range.clone())
363 .flat_map(str::chars)
364 {
365 if ch.is_whitespace() {
366 if whitespace_sequence_length == 0 {
367 whitespace_sequence_start = current_offset;
368 }
369 whitespace_sequence_length += 1;
370 } else {
371 if whitespace_sequence_length >= 2 {
372 whitespace_sequences.push((whitespace_sequence_start, current_offset));
373 }
374 whitespace_sequence_start = 0;
375 whitespace_sequence_length = 0;
376 }
377 current_offset += ch.len_utf8();
378 }
379 if whitespace_sequence_length >= 2 {
380 whitespace_sequences.push((whitespace_sequence_start, current_offset));
381 }
382
383 let closest_whitespace_end = if is_backward {
384 whitespace_sequences.last().map(|&(start, _)| start)
385 } else {
386 whitespace_sequences.first().map(|&(_, end)| end)
387 };
388
389 closest_whitespace_end
390 .unwrap_or_else(|| {
391 if is_backward {
392 trimmed_delete_range.start
393 } else {
394 trimmed_delete_range.end
395 }
396 })
397 .to_display_point(map)
398}
399
400/// Returns a position of the previous subword boundary, where a subword is defined as a run of
401/// word characters of the same "subkind" - where subcharacter kinds are '_' character,
402/// lowerspace characters and uppercase characters.
403pub fn previous_subword_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
404 let raw_point = point.to_point(map);
405 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
406
407 find_preceding_boundary_display_point(map, point, FindRange::MultiLine, |left, right| {
408 is_subword_start(left, right, &classifier) || left == '\n'
409 })
410}
411
412pub fn is_subword_start(left: char, right: char, classifier: &CharClassifier) -> bool {
413 let is_word_start = classifier.kind(left) != classifier.kind(right) && !right.is_whitespace();
414 let is_subword_start = classifier.is_word('-') && left == '-' && right != '-'
415 || left == '_' && right != '_'
416 || left.is_lowercase() && right.is_uppercase();
417 is_word_start || is_subword_start
418}
419
420/// Returns a position of the next word boundary, where a word character is defined as either
421/// uppercase letter, lowercase letter, '_' character or language-specific word character (like '-' in CSS).
422pub fn next_word_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
423 let raw_point = point.to_point(map);
424 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
425 let mut is_first_iteration = true;
426 find_boundary(map, point, FindRange::MultiLine, |left, right| {
427 // Make alt-right skip punctuation to respect VSCode behaviour. For example: |.hello goes to .hello|
428 if is_first_iteration
429 && classifier.is_punctuation(left)
430 && !classifier.is_punctuation(right)
431 && right != '\n'
432 {
433 is_first_iteration = false;
434 return false;
435 }
436 is_first_iteration = false;
437
438 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(left))
439 || right == '\n'
440 })
441}
442
443/// Returns a position of the next word boundary, where a word character is defined as either
444/// uppercase letter, lowercase letter, '_' character, language-specific word character (like '-' in CSS) or newline.
445pub fn next_word_end_or_newline(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
446 let raw_point = point.to_point(map);
447 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
448
449 let mut on_starting_row = true;
450 find_boundary(map, point, FindRange::MultiLine, |left, right| {
451 if left == '\n' {
452 on_starting_row = false;
453 }
454 (classifier.kind(left) != classifier.kind(right)
455 && ((on_starting_row && !left.is_whitespace())
456 || (!on_starting_row && !right.is_whitespace())))
457 || right == '\n'
458 })
459}
460
461/// Returns a position of the next subword boundary, where a subword is defined as a run of
462/// word characters of the same "subkind" - where subcharacter kinds are '_' character,
463/// lowerspace characters and uppercase characters.
464pub fn next_subword_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
465 let raw_point = point.to_point(map);
466 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
467
468 find_boundary(map, point, FindRange::MultiLine, |left, right| {
469 is_subword_end(left, right, &classifier) || right == '\n'
470 })
471}
472
473pub fn is_subword_end(left: char, right: char, classifier: &CharClassifier) -> bool {
474 let is_word_end =
475 (classifier.kind(left) != classifier.kind(right)) && !classifier.is_whitespace(left);
476 let is_subword_end = classifier.is_word('-') && left != '-' && right == '-'
477 || left != '_' && right == '_'
478 || left.is_lowercase() && right.is_uppercase();
479 is_word_end || is_subword_end
480}
481
482/// Returns a position of the start of the current paragraph, where a paragraph
483/// is defined as a run of non-blank lines.
484pub fn start_of_paragraph(
485 map: &DisplaySnapshot,
486 display_point: DisplayPoint,
487 mut count: usize,
488) -> DisplayPoint {
489 let point = display_point.to_point(map);
490 if point.row == 0 {
491 return DisplayPoint::zero();
492 }
493
494 let mut found_non_blank_line = false;
495 for row in (0..point.row + 1).rev() {
496 let blank = map.buffer_snapshot.is_line_blank(MultiBufferRow(row));
497 if found_non_blank_line && blank {
498 if count <= 1 {
499 return Point::new(row, 0).to_display_point(map);
500 }
501 count -= 1;
502 found_non_blank_line = false;
503 }
504
505 found_non_blank_line |= !blank;
506 }
507
508 DisplayPoint::zero()
509}
510
511/// Returns a position of the end of the current paragraph, where a paragraph
512/// is defined as a run of non-blank lines.
513pub fn end_of_paragraph(
514 map: &DisplaySnapshot,
515 display_point: DisplayPoint,
516 mut count: usize,
517) -> DisplayPoint {
518 let point = display_point.to_point(map);
519 if point.row == map.buffer_snapshot.max_row().0 {
520 return map.max_point();
521 }
522
523 let mut found_non_blank_line = false;
524 for row in point.row..=map.buffer_snapshot.max_row().0 {
525 let blank = map.buffer_snapshot.is_line_blank(MultiBufferRow(row));
526 if found_non_blank_line && blank {
527 if count <= 1 {
528 return Point::new(row, 0).to_display_point(map);
529 }
530 count -= 1;
531 found_non_blank_line = false;
532 }
533
534 found_non_blank_line |= !blank;
535 }
536
537 map.max_point()
538}
539
540pub fn start_of_excerpt(
541 map: &DisplaySnapshot,
542 display_point: DisplayPoint,
543 direction: Direction,
544) -> DisplayPoint {
545 let point = map.display_point_to_point(display_point, Bias::Left);
546 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point..point) else {
547 return display_point;
548 };
549 match direction {
550 Direction::Prev => {
551 let mut start = excerpt.start_anchor().to_display_point(map);
552 if start >= display_point && start.row() > DisplayRow(0) {
553 let Some(excerpt) = map.buffer_snapshot.excerpt_before(excerpt.id()) else {
554 return display_point;
555 };
556 start = excerpt.start_anchor().to_display_point(map);
557 }
558 start
559 }
560 Direction::Next => {
561 let mut end = excerpt.end_anchor().to_display_point(map);
562 *end.row_mut() += 1;
563 map.clip_point(end, Bias::Right)
564 }
565 }
566}
567
568pub fn end_of_excerpt(
569 map: &DisplaySnapshot,
570 display_point: DisplayPoint,
571 direction: Direction,
572) -> DisplayPoint {
573 let point = map.display_point_to_point(display_point, Bias::Left);
574 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point..point) else {
575 return display_point;
576 };
577 match direction {
578 Direction::Prev => {
579 let mut start = excerpt.start_anchor().to_display_point(map);
580 if start.row() > DisplayRow(0) {
581 *start.row_mut() -= 1;
582 }
583 start = map.clip_point(start, Bias::Left);
584 *start.column_mut() = 0;
585 start
586 }
587 Direction::Next => {
588 let mut end = excerpt.end_anchor().to_display_point(map);
589 *end.column_mut() = 0;
590 if end <= display_point {
591 *end.row_mut() += 1;
592 let point_end = map.display_point_to_point(end, Bias::Right);
593 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point_end..point_end)
594 else {
595 return display_point;
596 };
597 end = excerpt.end_anchor().to_display_point(map);
598 *end.column_mut() = 0;
599 }
600 end
601 }
602 }
603}
604
605/// Scans for a boundary preceding the given start point `from` until a boundary is found,
606/// indicated by the given predicate returning true.
607/// The predicate is called with the character to the left and right of the candidate boundary location.
608/// If FindRange::SingleLine is specified and no boundary is found before the start of the current line, the start of the current line will be returned.
609pub fn find_preceding_boundary_point(
610 buffer_snapshot: &MultiBufferSnapshot,
611 from: Point,
612 find_range: FindRange,
613 mut is_boundary: impl FnMut(char, char) -> bool,
614) -> Point {
615 let mut prev_ch = None;
616 let mut offset = from.to_offset(buffer_snapshot);
617
618 for ch in buffer_snapshot.reversed_chars_at(offset) {
619 if find_range == FindRange::SingleLine && ch == '\n' {
620 break;
621 }
622 if let Some(prev_ch) = prev_ch
623 && is_boundary(ch, prev_ch)
624 {
625 break;
626 }
627
628 offset -= ch.len_utf8();
629 prev_ch = Some(ch);
630 }
631
632 offset.to_point(buffer_snapshot)
633}
634
635/// Scans for a boundary preceding the given start point `from` until a boundary is found,
636/// indicated by the given predicate returning true.
637/// The predicate is called with the character to the left and right of the candidate boundary location.
638/// If FindRange::SingleLine is specified and no boundary is found before the start of the current line, the start of the current line will be returned.
639pub fn find_preceding_boundary_display_point(
640 map: &DisplaySnapshot,
641 from: DisplayPoint,
642 find_range: FindRange,
643 is_boundary: impl FnMut(char, char) -> bool,
644) -> DisplayPoint {
645 let result = find_preceding_boundary_point(
646 &map.buffer_snapshot,
647 from.to_point(map),
648 find_range,
649 is_boundary,
650 );
651 map.clip_point(result.to_display_point(map), Bias::Left)
652}
653
654/// Scans for a boundary following the given start point until a boundary is found, indicated by the
655/// given predicate returning true. The predicate is called with the character to the left and right
656/// of the candidate boundary location, and will be called with `\n` characters indicating the start
657/// or end of a line. The function supports optionally returning the point just before the boundary
658/// is found via return_point_before_boundary.
659pub fn find_boundary_point(
660 map: &DisplaySnapshot,
661 from: DisplayPoint,
662 find_range: FindRange,
663 mut is_boundary: impl FnMut(char, char) -> bool,
664 return_point_before_boundary: bool,
665) -> DisplayPoint {
666 let mut offset = from.to_offset(map, Bias::Right);
667 let mut prev_offset = offset;
668 let mut prev_ch = None;
669
670 for ch in map.buffer_snapshot.chars_at(offset) {
671 if find_range == FindRange::SingleLine && ch == '\n' {
672 break;
673 }
674 if let Some(prev_ch) = prev_ch
675 && is_boundary(prev_ch, ch)
676 {
677 if return_point_before_boundary {
678 return map.clip_point(prev_offset.to_display_point(map), Bias::Right);
679 } else {
680 break;
681 }
682 }
683 prev_offset = offset;
684 offset += ch.len_utf8();
685 prev_ch = Some(ch);
686 }
687 map.clip_point(offset.to_display_point(map), Bias::Right)
688}
689
690pub fn find_preceding_boundary_trail(
691 map: &DisplaySnapshot,
692 head: DisplayPoint,
693 mut is_boundary: impl FnMut(char, char) -> bool,
694) -> (Option<DisplayPoint>, DisplayPoint) {
695 let mut offset = head.to_offset(map, Bias::Left);
696 let mut trail_offset = None;
697
698 let mut prev_ch = map.buffer_snapshot.chars_at(offset).next();
699 let mut forward = map.buffer_snapshot.reversed_chars_at(offset).peekable();
700
701 // Skip newlines
702 while let Some(&ch) = forward.peek() {
703 if ch == '\n' {
704 prev_ch = forward.next();
705 offset -= ch.len_utf8();
706 trail_offset = Some(offset);
707 } else {
708 break;
709 }
710 }
711
712 // Find the boundary
713 let start_offset = offset;
714 for ch in forward {
715 if let Some(prev_ch) = prev_ch
716 && is_boundary(prev_ch, ch)
717 {
718 if start_offset == offset {
719 trail_offset = Some(offset);
720 } else {
721 break;
722 }
723 }
724 offset -= ch.len_utf8();
725 prev_ch = Some(ch);
726 }
727
728 let trail = trail_offset
729 .map(|trail_offset: usize| map.clip_point(trail_offset.to_display_point(map), Bias::Left));
730
731 (
732 trail,
733 map.clip_point(offset.to_display_point(map), Bias::Left),
734 )
735}
736
737/// Finds the location of a boundary
738pub fn find_boundary_trail(
739 map: &DisplaySnapshot,
740 head: DisplayPoint,
741 mut is_boundary: impl FnMut(char, char) -> bool,
742) -> (Option<DisplayPoint>, DisplayPoint) {
743 let mut offset = head.to_offset(map, Bias::Right);
744 let mut trail_offset = None;
745
746 let mut prev_ch = map.buffer_snapshot.reversed_chars_at(offset).next();
747 let mut forward = map.buffer_snapshot.chars_at(offset).peekable();
748
749 // Skip newlines
750 while let Some(&ch) = forward.peek() {
751 if ch == '\n' {
752 prev_ch = forward.next();
753 offset += ch.len_utf8();
754 trail_offset = Some(offset);
755 } else {
756 break;
757 }
758 }
759
760 // Find the boundary
761 let start_offset = offset;
762 for ch in forward {
763 if let Some(prev_ch) = prev_ch
764 && is_boundary(prev_ch, ch)
765 {
766 if start_offset == offset {
767 trail_offset = Some(offset);
768 } else {
769 break;
770 }
771 }
772 offset += ch.len_utf8();
773 prev_ch = Some(ch);
774 }
775
776 let trail = trail_offset
777 .map(|trail_offset: usize| map.clip_point(trail_offset.to_display_point(map), Bias::Right));
778
779 (
780 trail,
781 map.clip_point(offset.to_display_point(map), Bias::Right),
782 )
783}
784
785pub fn find_boundary(
786 map: &DisplaySnapshot,
787 from: DisplayPoint,
788 find_range: FindRange,
789 is_boundary: impl FnMut(char, char) -> bool,
790) -> DisplayPoint {
791 find_boundary_point(map, from, find_range, is_boundary, false)
792}
793
794pub fn find_boundary_exclusive(
795 map: &DisplaySnapshot,
796 from: DisplayPoint,
797 find_range: FindRange,
798 is_boundary: impl FnMut(char, char) -> bool,
799) -> DisplayPoint {
800 find_boundary_point(map, from, find_range, is_boundary, true)
801}
802
803/// Returns an iterator over the characters following a given offset in the [`DisplaySnapshot`].
804/// The returned value also contains a range of the start/end of a returned character in
805/// the [`DisplaySnapshot`]. The offsets are relative to the start of a buffer.
806pub fn chars_after(
807 map: &DisplaySnapshot,
808 mut offset: usize,
809) -> impl Iterator<Item = (char, Range<usize>)> + '_ {
810 map.buffer_snapshot.chars_at(offset).map(move |ch| {
811 let before = offset;
812 offset += ch.len_utf8();
813 (ch, before..offset)
814 })
815}
816
817/// Returns a reverse iterator over the characters following a given offset in the [`DisplaySnapshot`].
818/// The returned value also contains a range of the start/end of a returned character in
819/// the [`DisplaySnapshot`]. The offsets are relative to the start of a buffer.
820pub fn chars_before(
821 map: &DisplaySnapshot,
822 mut offset: usize,
823) -> impl Iterator<Item = (char, Range<usize>)> + '_ {
824 map.buffer_snapshot
825 .reversed_chars_at(offset)
826 .map(move |ch| {
827 let after = offset;
828 offset -= ch.len_utf8();
829 (ch, offset..after)
830 })
831}
832
833/// Returns a list of lines (represented as a [`DisplayPoint`] range) contained
834/// within a passed range.
835///
836/// The line ranges are **always* going to be in bounds of a requested range, which means that
837/// the first and the last lines might not necessarily represent the
838/// full range of a logical line (as their `.start`/`.end` values are clipped to those of a passed in range).
839pub fn split_display_range_by_lines(
840 map: &DisplaySnapshot,
841 range: Range<DisplayPoint>,
842) -> Vec<Range<DisplayPoint>> {
843 let mut result = Vec::new();
844
845 let mut start = range.start;
846 // Loop over all the covered rows until the one containing the range end
847 for row in range.start.row().0..range.end.row().0 {
848 let row_end_column = map.line_len(DisplayRow(row));
849 let end = map.clip_point(
850 DisplayPoint::new(DisplayRow(row), row_end_column),
851 Bias::Left,
852 );
853 if start != end {
854 result.push(start..end);
855 }
856 start = map.clip_point(DisplayPoint::new(DisplayRow(row + 1), 0), Bias::Left);
857 }
858
859 // Add the final range from the start of the last end to the original range end.
860 result.push(start..range.end);
861
862 result
863}
864
865#[cfg(test)]
866mod tests {
867 use super::*;
868 use crate::{
869 Buffer, DisplayMap, DisplayRow, ExcerptRange, FoldPlaceholder, MultiBuffer,
870 display_map::Inlay,
871 test::{editor_test_context::EditorTestContext, marked_display_snapshot},
872 };
873 use gpui::{AppContext as _, font, px};
874 use language::Capability;
875 use project::{Project, project_settings::DiagnosticSeverity};
876 use settings::SettingsStore;
877 use util::post_inc;
878
879 #[gpui::test]
880 fn test_previous_word_start(cx: &mut gpui::App) {
881 init_test(cx);
882
883 fn assert(marked_text: &str, cx: &mut gpui::App) {
884 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
885 let actual = previous_word_start(&snapshot, display_points[1]);
886 let expected = display_points[0];
887 if actual != expected {
888 eprintln!(
889 "previous_word_start mismatch for '{}': actual={:?}, expected={:?}",
890 marked_text, actual, expected
891 );
892 }
893 assert_eq!(actual, expected);
894 }
895
896 assert("\nˇ ˇlorem", cx);
897 assert("ˇ\nˇ lorem", cx);
898 assert(" ˇloremˇ", cx);
899 assert("ˇ ˇlorem", cx);
900 assert(" ˇlorˇem", cx);
901 assert("\nlorem\nˇ ˇipsum", cx);
902 assert("\n\nˇ\nˇ", cx);
903 assert(" ˇlorem ˇipsum", cx);
904 assert("ˇlorem-ˇipsum", cx);
905 assert("loremˇ-#$@ˇipsum", cx);
906 assert("ˇlorem_ˇipsum", cx);
907 assert(" ˇdefγˇ", cx);
908 assert(" ˇbcΔˇ", cx);
909 // Test punctuation skipping behavior
910 assert("ˇhello.ˇ", cx);
911 assert("helloˇ...ˇ", cx);
912 assert("helloˇ.---..ˇtest", cx);
913 assert("test ˇ.--ˇtest", cx);
914 assert("oneˇ,;:!?ˇtwo", cx);
915 }
916
917 #[gpui::test]
918 fn test_previous_subword_start(cx: &mut gpui::App) {
919 init_test(cx);
920
921 fn assert(marked_text: &str, cx: &mut gpui::App) {
922 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
923 assert_eq!(
924 previous_subword_start(&snapshot, display_points[1]),
925 display_points[0]
926 );
927 }
928
929 // Subword boundaries are respected
930 assert("lorem_ˇipˇsum", cx);
931 assert("lorem_ˇipsumˇ", cx);
932 assert("ˇlorem_ˇipsum", cx);
933 assert("lorem_ˇipsum_ˇdolor", cx);
934 assert("loremˇIpˇsum", cx);
935 assert("loremˇIpsumˇ", cx);
936
937 // Word boundaries are still respected
938 assert("\nˇ ˇlorem", cx);
939 assert(" ˇloremˇ", cx);
940 assert(" ˇlorˇem", cx);
941 assert("\nlorem\nˇ ˇipsum", cx);
942 assert("\n\nˇ\nˇ", cx);
943 assert(" ˇlorem ˇipsum", cx);
944 assert("loremˇ-ˇipsum", cx);
945 assert("loremˇ-#$@ˇipsum", cx);
946 assert(" ˇdefγˇ", cx);
947 assert(" bcˇΔˇ", cx);
948 assert(" ˇbcδˇ", cx);
949 assert(" abˇ——ˇcd", cx);
950 }
951
952 #[gpui::test]
953 fn test_find_preceding_boundary(cx: &mut gpui::App) {
954 init_test(cx);
955
956 fn assert(
957 marked_text: &str,
958 cx: &mut gpui::App,
959 is_boundary: impl FnMut(char, char) -> bool,
960 ) {
961 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
962 assert_eq!(
963 find_preceding_boundary_display_point(
964 &snapshot,
965 display_points[1],
966 FindRange::MultiLine,
967 is_boundary
968 ),
969 display_points[0]
970 );
971 }
972
973 assert("abcˇdef\ngh\nijˇk", cx, |left, right| {
974 left == 'c' && right == 'd'
975 });
976 assert("abcdef\nˇgh\nijˇk", cx, |left, right| {
977 left == '\n' && right == 'g'
978 });
979 let mut line_count = 0;
980 assert("abcdef\nˇgh\nijˇk", cx, |left, _| {
981 if left == '\n' {
982 line_count += 1;
983 line_count == 2
984 } else {
985 false
986 }
987 });
988 }
989
990 #[gpui::test]
991 fn test_find_preceding_boundary_with_inlays(cx: &mut gpui::App) {
992 init_test(cx);
993
994 let input_text = "abcdefghijklmnopqrstuvwxys";
995 let font = font("Helvetica");
996 let font_size = px(14.0);
997 let buffer = MultiBuffer::build_simple(input_text, cx);
998 let buffer_snapshot = buffer.read(cx).snapshot(cx);
999
1000 let display_map = cx.new(|cx| {
1001 DisplayMap::new(
1002 buffer,
1003 font,
1004 font_size,
1005 None,
1006 1,
1007 1,
1008 FoldPlaceholder::test(),
1009 DiagnosticSeverity::Warning,
1010 cx,
1011 )
1012 });
1013
1014 // add all kinds of inlays between two word boundaries: we should be able to cross them all, when looking for another boundary
1015 let mut id = 0;
1016 let inlays = (0..buffer_snapshot.len())
1017 .flat_map(|offset| {
1018 [
1019 Inlay::edit_prediction(
1020 post_inc(&mut id),
1021 buffer_snapshot.anchor_before(offset),
1022 "test",
1023 ),
1024 Inlay::edit_prediction(
1025 post_inc(&mut id),
1026 buffer_snapshot.anchor_after(offset),
1027 "test",
1028 ),
1029 Inlay::mock_hint(
1030 post_inc(&mut id),
1031 buffer_snapshot.anchor_before(offset),
1032 "test",
1033 ),
1034 Inlay::mock_hint(
1035 post_inc(&mut id),
1036 buffer_snapshot.anchor_after(offset),
1037 "test",
1038 ),
1039 ]
1040 })
1041 .collect();
1042 let snapshot = display_map.update(cx, |map, cx| {
1043 map.splice_inlays(&[], inlays, cx);
1044 map.snapshot(cx)
1045 });
1046
1047 assert_eq!(
1048 find_preceding_boundary_display_point(
1049 &snapshot,
1050 buffer_snapshot.len().to_display_point(&snapshot),
1051 FindRange::MultiLine,
1052 |left, _| left == 'e',
1053 ),
1054 snapshot
1055 .buffer_snapshot
1056 .offset_to_point(5)
1057 .to_display_point(&snapshot),
1058 "Should not stop at inlays when looking for boundaries"
1059 );
1060 }
1061
1062 #[gpui::test]
1063 fn test_next_word_end(cx: &mut gpui::App) {
1064 init_test(cx);
1065
1066 fn assert(marked_text: &str, cx: &mut gpui::App) {
1067 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1068 let actual = next_word_end(&snapshot, display_points[0]);
1069 let expected = display_points[1];
1070 if actual != expected {
1071 eprintln!(
1072 "next_word_end mismatch for '{}': actual={:?}, expected={:?}",
1073 marked_text, actual, expected
1074 );
1075 }
1076 assert_eq!(actual, expected);
1077 }
1078
1079 assert("\nˇ loremˇ", cx);
1080 assert(" ˇloremˇ", cx);
1081 assert(" lorˇemˇ", cx);
1082 assert(" loremˇ ˇ\nipsum\n", cx);
1083 assert("\nˇ\nˇ\n\n", cx);
1084 assert("loremˇ ipsumˇ ", cx);
1085 assert("loremˇ-ipsumˇ", cx);
1086 assert("loremˇ#$@-ˇipsum", cx);
1087 assert("loremˇ_ipsumˇ", cx);
1088 assert(" ˇbcΔˇ", cx);
1089 assert(" abˇ——ˇcd", cx);
1090 // Test punctuation skipping behavior
1091 assert("ˇ.helloˇ", cx);
1092 assert("display_pointsˇ[0ˇ]", cx);
1093 assert("ˇ...ˇhello", cx);
1094 assert("helloˇ.---..ˇtest", cx);
1095 assert("testˇ.--ˇ test", cx);
1096 assert("oneˇ,;:!?ˇtwo", cx);
1097 }
1098
1099 #[gpui::test]
1100 fn test_next_subword_end(cx: &mut gpui::App) {
1101 init_test(cx);
1102
1103 fn assert(marked_text: &str, cx: &mut gpui::App) {
1104 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1105 assert_eq!(
1106 next_subword_end(&snapshot, display_points[0]),
1107 display_points[1]
1108 );
1109 }
1110
1111 // Subword boundaries are respected
1112 assert("loˇremˇ_ipsum", cx);
1113 assert("ˇloremˇ_ipsum", cx);
1114 assert("loremˇ_ipsumˇ", cx);
1115 assert("loremˇ_ipsumˇ_dolor", cx);
1116 assert("loˇremˇIpsum", cx);
1117 assert("loremˇIpsumˇDolor", cx);
1118
1119 // Word boundaries are still respected
1120 assert("\nˇ loremˇ", cx);
1121 assert(" ˇloremˇ", cx);
1122 assert(" lorˇemˇ", cx);
1123 assert(" loremˇ ˇ\nipsum\n", cx);
1124 assert("\nˇ\nˇ\n\n", cx);
1125 assert("loremˇ ipsumˇ ", cx);
1126 assert("loremˇ-ˇipsum", cx);
1127 assert("loremˇ#$@-ˇipsum", cx);
1128 assert("loremˇ_ipsumˇ", cx);
1129 assert(" ˇbcˇΔ", cx);
1130 assert(" abˇ——ˇcd", cx);
1131 }
1132
1133 #[gpui::test]
1134 fn test_find_boundary(cx: &mut gpui::App) {
1135 init_test(cx);
1136
1137 fn assert(
1138 marked_text: &str,
1139 cx: &mut gpui::App,
1140 is_boundary: impl FnMut(char, char) -> bool,
1141 ) {
1142 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1143 assert_eq!(
1144 find_boundary(
1145 &snapshot,
1146 display_points[0],
1147 FindRange::MultiLine,
1148 is_boundary,
1149 ),
1150 display_points[1]
1151 );
1152 }
1153
1154 assert("abcˇdef\ngh\nijˇk", cx, |left, right| {
1155 left == 'j' && right == 'k'
1156 });
1157 assert("abˇcdef\ngh\nˇijk", cx, |left, right| {
1158 left == '\n' && right == 'i'
1159 });
1160 let mut line_count = 0;
1161 assert("abcˇdef\ngh\nˇijk", cx, |left, _| {
1162 if left == '\n' {
1163 line_count += 1;
1164 line_count == 2
1165 } else {
1166 false
1167 }
1168 });
1169 }
1170
1171 #[gpui::test]
1172 async fn test_move_up_and_down_with_excerpts(cx: &mut gpui::TestAppContext) {
1173 cx.update(|cx| {
1174 init_test(cx);
1175 });
1176
1177 let mut cx = EditorTestContext::new(cx).await;
1178 let editor = cx.editor.clone();
1179 let window = cx.window;
1180 _ = cx.update_window(window, |_, window, cx| {
1181 let text_layout_details = editor.read(cx).text_layout_details(window);
1182
1183 let font = font("Helvetica");
1184
1185 let buffer = cx.new(|cx| Buffer::local("abc\ndefg\nhijkl\nmn", cx));
1186 let multibuffer = cx.new(|cx| {
1187 let mut multibuffer = MultiBuffer::new(Capability::ReadWrite);
1188 multibuffer.push_excerpts(
1189 buffer.clone(),
1190 [
1191 ExcerptRange::new(Point::new(0, 0)..Point::new(1, 4)),
1192 ExcerptRange::new(Point::new(2, 0)..Point::new(3, 2)),
1193 ],
1194 cx,
1195 );
1196 multibuffer
1197 });
1198 let display_map = cx.new(|cx| {
1199 DisplayMap::new(
1200 multibuffer,
1201 font,
1202 px(14.0),
1203 None,
1204 0,
1205 1,
1206 FoldPlaceholder::test(),
1207 DiagnosticSeverity::Warning,
1208 cx,
1209 )
1210 });
1211 let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
1212
1213 assert_eq!(snapshot.text(), "abc\ndefg\n\nhijkl\nmn");
1214
1215 let col_2_x = snapshot
1216 .x_for_display_point(DisplayPoint::new(DisplayRow(0), 2), &text_layout_details);
1217
1218 // Can't move up into the first excerpt's header
1219 assert_eq!(
1220 up(
1221 &snapshot,
1222 DisplayPoint::new(DisplayRow(0), 2),
1223 SelectionGoal::HorizontalPosition(col_2_x.0),
1224 false,
1225 &text_layout_details
1226 ),
1227 (
1228 DisplayPoint::new(DisplayRow(0), 0),
1229 SelectionGoal::HorizontalPosition(col_2_x.0),
1230 ),
1231 );
1232 assert_eq!(
1233 up(
1234 &snapshot,
1235 DisplayPoint::new(DisplayRow(0), 0),
1236 SelectionGoal::None,
1237 false,
1238 &text_layout_details
1239 ),
1240 (
1241 DisplayPoint::new(DisplayRow(0), 0),
1242 SelectionGoal::HorizontalPosition(0.0),
1243 ),
1244 );
1245
1246 let col_4_x = snapshot
1247 .x_for_display_point(DisplayPoint::new(DisplayRow(1), 4), &text_layout_details);
1248
1249 // Move up and down within first excerpt
1250 assert_eq!(
1251 up(
1252 &snapshot,
1253 DisplayPoint::new(DisplayRow(1), 4),
1254 SelectionGoal::HorizontalPosition(col_4_x.0),
1255 false,
1256 &text_layout_details
1257 ),
1258 (
1259 DisplayPoint::new(DisplayRow(0), 3),
1260 SelectionGoal::HorizontalPosition(col_4_x.0)
1261 ),
1262 );
1263 assert_eq!(
1264 down(
1265 &snapshot,
1266 DisplayPoint::new(DisplayRow(0), 3),
1267 SelectionGoal::HorizontalPosition(col_4_x.0),
1268 false,
1269 &text_layout_details
1270 ),
1271 (
1272 DisplayPoint::new(DisplayRow(1), 4),
1273 SelectionGoal::HorizontalPosition(col_4_x.0)
1274 ),
1275 );
1276
1277 let col_5_x = snapshot
1278 .x_for_display_point(DisplayPoint::new(DisplayRow(3), 5), &text_layout_details);
1279
1280 // Move up and down across second excerpt's header
1281 assert_eq!(
1282 up(
1283 &snapshot,
1284 DisplayPoint::new(DisplayRow(3), 5),
1285 SelectionGoal::HorizontalPosition(col_5_x.0),
1286 false,
1287 &text_layout_details
1288 ),
1289 (
1290 DisplayPoint::new(DisplayRow(1), 4),
1291 SelectionGoal::HorizontalPosition(col_5_x.0)
1292 ),
1293 );
1294 assert_eq!(
1295 down(
1296 &snapshot,
1297 DisplayPoint::new(DisplayRow(1), 4),
1298 SelectionGoal::HorizontalPosition(col_5_x.0),
1299 false,
1300 &text_layout_details
1301 ),
1302 (
1303 DisplayPoint::new(DisplayRow(3), 5),
1304 SelectionGoal::HorizontalPosition(col_5_x.0)
1305 ),
1306 );
1307
1308 let max_point_x = snapshot
1309 .x_for_display_point(DisplayPoint::new(DisplayRow(4), 2), &text_layout_details);
1310
1311 // Can't move down off the end, and attempting to do so leaves the selection goal unchanged
1312 assert_eq!(
1313 down(
1314 &snapshot,
1315 DisplayPoint::new(DisplayRow(4), 0),
1316 SelectionGoal::HorizontalPosition(0.0),
1317 false,
1318 &text_layout_details
1319 ),
1320 (
1321 DisplayPoint::new(DisplayRow(4), 2),
1322 SelectionGoal::HorizontalPosition(0.0)
1323 ),
1324 );
1325 assert_eq!(
1326 down(
1327 &snapshot,
1328 DisplayPoint::new(DisplayRow(4), 2),
1329 SelectionGoal::HorizontalPosition(max_point_x.0),
1330 false,
1331 &text_layout_details
1332 ),
1333 (
1334 DisplayPoint::new(DisplayRow(4), 2),
1335 SelectionGoal::HorizontalPosition(max_point_x.0)
1336 ),
1337 );
1338 });
1339 }
1340
1341 fn init_test(cx: &mut gpui::App) {
1342 let settings_store = SettingsStore::test(cx);
1343 cx.set_global(settings_store);
1344 workspace::init_settings(cx);
1345 theme::init(theme::LoadThemes::JustBase, cx);
1346 language::init(cx);
1347 crate::init(cx);
1348 Project::init_settings(cx);
1349 }
1350}