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::{
6 DisplayRow, EditorStyle, ToOffset, ToPoint,
7 scroll::{ScrollAnchor, ScrollOffset},
8};
9use gpui::{Pixels, WindowTextSystem};
10use language::{CharClassifier, Point};
11use multi_buffer::{MultiBufferRow, MultiBufferSnapshot};
12use serde::Deserialize;
13use workspace::searchable::Direction;
14
15use std::{ops::Range, sync::Arc};
16
17/// Defines search strategy for items in `movement` module.
18/// `FindRange::SingeLine` only looks for a match on a single line at a time, whereas
19/// `FindRange::MultiLine` keeps going until the end of a string.
20#[derive(Clone, Copy, Debug, PartialEq, Eq, Deserialize)]
21pub enum FindRange {
22 SingleLine,
23 MultiLine,
24}
25
26/// TextLayoutDetails encompasses everything we need to move vertically
27/// taking into account variable width characters.
28pub struct TextLayoutDetails {
29 pub(crate) text_system: Arc<WindowTextSystem>,
30 pub(crate) editor_style: EditorStyle,
31 pub(crate) rem_size: Pixels,
32 pub scroll_anchor: ScrollAnchor,
33 pub visible_rows: Option<f64>,
34 pub vertical_scroll_margin: ScrollOffset,
35}
36
37/// Returns a column to the left of the current point, wrapping
38/// to the previous line if that point is at the start of line.
39pub fn left(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
40 if point.column() > 0 {
41 *point.column_mut() -= 1;
42 } else if point.row().0 > 0 {
43 *point.row_mut() -= 1;
44 *point.column_mut() = map.line_len(point.row());
45 }
46 map.clip_point(point, Bias::Left)
47}
48
49/// Returns a column to the left of the current point, doing nothing if
50/// that point is already at the start of line.
51pub fn saturating_left(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
52 if point.column() > 0 {
53 *point.column_mut() -= 1;
54 } else if point.column() == 0 {
55 // If the current sofr_wrap mode is used, the column corresponding to the display is 0,
56 // which does not necessarily mean that the actual beginning of a paragraph
57 if map.display_point_to_fold_point(point, Bias::Left).column() > 0 {
58 return left(map, point);
59 }
60 }
61 map.clip_point(point, Bias::Left)
62}
63
64/// Returns a column to the right of the current point, wrapping
65/// to the next line if that point is at the end of line.
66pub fn right(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
67 if point.column() < map.line_len(point.row()) {
68 *point.column_mut() += 1;
69 } else if point.row() < map.max_point().row() {
70 *point.row_mut() += 1;
71 *point.column_mut() = 0;
72 }
73 map.clip_point(point, Bias::Right)
74}
75
76/// Returns a column to the right of the current point, not performing any wrapping
77/// if that point is already at the end of line.
78pub fn saturating_right(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
79 *point.column_mut() += 1;
80 map.clip_point(point, Bias::Right)
81}
82
83/// Returns a display point for the preceding displayed line (which might be a soft-wrapped line).
84pub fn up(
85 map: &DisplaySnapshot,
86 start: DisplayPoint,
87 goal: SelectionGoal,
88 preserve_column_at_start: bool,
89 text_layout_details: &TextLayoutDetails,
90) -> (DisplayPoint, SelectionGoal) {
91 up_by_rows(
92 map,
93 start,
94 1,
95 goal,
96 preserve_column_at_start,
97 text_layout_details,
98 )
99}
100
101/// Returns a display point for the next displayed line (which might be a soft-wrapped line).
102pub fn down(
103 map: &DisplaySnapshot,
104 start: DisplayPoint,
105 goal: SelectionGoal,
106 preserve_column_at_end: bool,
107 text_layout_details: &TextLayoutDetails,
108) -> (DisplayPoint, SelectionGoal) {
109 down_by_rows(
110 map,
111 start,
112 1,
113 goal,
114 preserve_column_at_end,
115 text_layout_details,
116 )
117}
118
119pub(crate) fn up_by_rows(
120 map: &DisplaySnapshot,
121 start: DisplayPoint,
122 row_count: u32,
123 goal: SelectionGoal,
124 preserve_column_at_start: bool,
125 text_layout_details: &TextLayoutDetails,
126) -> (DisplayPoint, SelectionGoal) {
127 let goal_x = match goal {
128 SelectionGoal::HorizontalPosition(x) => x.into(),
129 SelectionGoal::WrappedHorizontalPosition((_, x)) => x.into(),
130 SelectionGoal::HorizontalRange { end, .. } => end.into(),
131 _ => map.x_for_display_point(start, text_layout_details),
132 };
133
134 let prev_row = DisplayRow(start.row().0.saturating_sub(row_count));
135 let mut point = map.clip_point(
136 DisplayPoint::new(prev_row, map.line_len(prev_row)),
137 Bias::Left,
138 );
139 if point.row() < start.row() {
140 *point.column_mut() = map.display_column_for_x(point.row(), goal_x, text_layout_details)
141 } else if preserve_column_at_start {
142 return (start, goal);
143 } else {
144 point = DisplayPoint::new(DisplayRow(0), 0);
145 }
146
147 let mut clipped_point = map.clip_point(point, Bias::Left);
148 if clipped_point.row() < point.row() {
149 clipped_point = map.clip_point(point, Bias::Right);
150 }
151 (
152 clipped_point,
153 SelectionGoal::HorizontalPosition(goal_x.into()),
154 )
155}
156
157pub(crate) fn down_by_rows(
158 map: &DisplaySnapshot,
159 start: DisplayPoint,
160 row_count: u32,
161 goal: SelectionGoal,
162 preserve_column_at_end: bool,
163 text_layout_details: &TextLayoutDetails,
164) -> (DisplayPoint, SelectionGoal) {
165 let goal_x = match goal {
166 SelectionGoal::HorizontalPosition(x) => x.into(),
167 SelectionGoal::WrappedHorizontalPosition((_, x)) => x.into(),
168 SelectionGoal::HorizontalRange { end, .. } => end.into(),
169 _ => map.x_for_display_point(start, text_layout_details),
170 };
171
172 let new_row = DisplayRow(start.row().0 + row_count);
173 let mut point = map.clip_point(DisplayPoint::new(new_row, 0), Bias::Right);
174 if point.row() > start.row() {
175 *point.column_mut() = map.display_column_for_x(point.row(), goal_x, text_layout_details)
176 } else if preserve_column_at_end {
177 return (start, goal);
178 } else {
179 point = map.max_point();
180 }
181
182 let mut clipped_point = map.clip_point(point, Bias::Right);
183 if clipped_point.row() > point.row() {
184 clipped_point = map.clip_point(point, Bias::Left);
185 }
186 (
187 clipped_point,
188 SelectionGoal::HorizontalPosition(goal_x.into()),
189 )
190}
191
192/// Returns a position of the start of line.
193/// If `stop_at_soft_boundaries` is true, the returned position is that of the
194/// displayed line (e.g. it could actually be in the middle of a text line if that line is soft-wrapped).
195/// Otherwise it's always going to be the start of a logical line.
196pub fn line_beginning(
197 map: &DisplaySnapshot,
198 display_point: DisplayPoint,
199 stop_at_soft_boundaries: bool,
200) -> DisplayPoint {
201 let point = display_point.to_point(map);
202 let soft_line_start = map.clip_point(DisplayPoint::new(display_point.row(), 0), Bias::Right);
203 let line_start = map.prev_line_boundary(point).1;
204
205 if stop_at_soft_boundaries && display_point != soft_line_start {
206 soft_line_start
207 } else {
208 line_start
209 }
210}
211
212/// Returns the last indented position on a given line.
213/// If `stop_at_soft_boundaries` is true, the returned [`DisplayPoint`] is that of a
214/// displayed line (e.g. if there's soft wrap it's gonna be returned),
215/// otherwise it's always going to be a start of a logical line.
216pub fn indented_line_beginning(
217 map: &DisplaySnapshot,
218 display_point: DisplayPoint,
219 stop_at_soft_boundaries: bool,
220 stop_at_indent: bool,
221) -> DisplayPoint {
222 let point = display_point.to_point(map);
223 let soft_line_start = map.clip_point(DisplayPoint::new(display_point.row(), 0), Bias::Right);
224 let indent_start = Point::new(
225 point.row,
226 map.buffer_snapshot
227 .indent_size_for_line(MultiBufferRow(point.row))
228 .len,
229 )
230 .to_display_point(map);
231 let line_start = map.prev_line_boundary(point).1;
232
233 if stop_at_soft_boundaries && soft_line_start > indent_start && display_point != soft_line_start
234 {
235 soft_line_start
236 } else if stop_at_indent && (display_point > indent_start || display_point == line_start) {
237 indent_start
238 } else {
239 line_start
240 }
241}
242
243/// Returns a position of the end of line.
244///
245/// If `stop_at_soft_boundaries` is true, the returned position is that of the
246/// displayed line (e.g. it could actually be in the middle of a text line if that line is soft-wrapped).
247/// Otherwise it's always going to be the end of a logical line.
248pub fn line_end(
249 map: &DisplaySnapshot,
250 display_point: DisplayPoint,
251 stop_at_soft_boundaries: bool,
252) -> DisplayPoint {
253 let soft_line_end = map.clip_point(
254 DisplayPoint::new(display_point.row(), map.line_len(display_point.row())),
255 Bias::Left,
256 );
257 if stop_at_soft_boundaries && display_point != soft_line_end {
258 soft_line_end
259 } else {
260 map.next_line_boundary(display_point.to_point(map)).1
261 }
262}
263
264/// Returns a position of the previous word boundary, where a word character is defined as either
265/// uppercase letter, lowercase letter, '_' character or language-specific word character (like '-' in CSS).
266pub fn previous_word_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
267 let raw_point = point.to_point(map);
268 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
269
270 let mut is_first_iteration = true;
271 find_preceding_boundary_display_point(map, point, FindRange::MultiLine, |left, right| {
272 // Make alt-left skip punctuation to respect VSCode behaviour. For example: hello.| goes to |hello.
273 if is_first_iteration
274 && classifier.is_punctuation(right)
275 && !classifier.is_punctuation(left)
276 && left != '\n'
277 {
278 is_first_iteration = false;
279 return false;
280 }
281 is_first_iteration = false;
282
283 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(right))
284 || left == '\n'
285 })
286}
287
288/// Returns a position of the previous word boundary, where a word character is defined as either
289/// uppercase letter, lowercase letter, '_' character, language-specific word character (like '-' in CSS) or newline.
290pub fn previous_word_start_or_newline(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
291 let raw_point = point.to_point(map);
292 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
293
294 find_preceding_boundary_display_point(map, point, FindRange::MultiLine, |left, right| {
295 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(right))
296 || left == '\n'
297 || right == '\n'
298 })
299}
300
301/// Text movements are too greedy, making deletions too greedy too.
302/// Makes deletions more ergonomic by potentially reducing the deletion range based on its text contents:
303/// * whitespace sequences with length >= 2 stop the deletion after removal (despite movement jumping over the word behind the whitespaces)
304/// * brackets stop the deletion after removal (despite movement currently not accounting for these and jumping over)
305pub fn adjust_greedy_deletion(
306 map: &DisplaySnapshot,
307 delete_from: DisplayPoint,
308 delete_until: DisplayPoint,
309 ignore_brackets: bool,
310) -> DisplayPoint {
311 if delete_from == delete_until {
312 return delete_until;
313 }
314 let is_backward = delete_from > delete_until;
315 let delete_range = if is_backward {
316 map.display_point_to_point(delete_until, Bias::Left)
317 .to_offset(&map.buffer_snapshot)
318 ..map
319 .display_point_to_point(delete_from, Bias::Right)
320 .to_offset(&map.buffer_snapshot)
321 } else {
322 map.display_point_to_point(delete_from, Bias::Left)
323 .to_offset(&map.buffer_snapshot)
324 ..map
325 .display_point_to_point(delete_until, Bias::Right)
326 .to_offset(&map.buffer_snapshot)
327 };
328
329 let trimmed_delete_range = if ignore_brackets {
330 delete_range
331 } else {
332 let brackets_in_delete_range = map
333 .buffer_snapshot
334 .bracket_ranges(delete_range.clone())
335 .into_iter()
336 .flatten()
337 .flat_map(|(left_bracket, right_bracket)| {
338 [
339 left_bracket.start,
340 left_bracket.end,
341 right_bracket.start,
342 right_bracket.end,
343 ]
344 })
345 .filter(|&bracket| delete_range.start < bracket && bracket < delete_range.end);
346 let closest_bracket = if is_backward {
347 brackets_in_delete_range.max()
348 } else {
349 brackets_in_delete_range.min()
350 };
351
352 if is_backward {
353 closest_bracket.unwrap_or(delete_range.start)..delete_range.end
354 } else {
355 delete_range.start..closest_bracket.unwrap_or(delete_range.end)
356 }
357 };
358
359 let mut whitespace_sequences = Vec::new();
360 let mut current_offset = trimmed_delete_range.start;
361 let mut whitespace_sequence_length = 0;
362 let mut whitespace_sequence_start = 0;
363 for ch in map
364 .buffer_snapshot
365 .text_for_range(trimmed_delete_range.clone())
366 .flat_map(str::chars)
367 {
368 if ch.is_whitespace() {
369 if whitespace_sequence_length == 0 {
370 whitespace_sequence_start = current_offset;
371 }
372 whitespace_sequence_length += 1;
373 } else {
374 if whitespace_sequence_length >= 2 {
375 whitespace_sequences.push((whitespace_sequence_start, current_offset));
376 }
377 whitespace_sequence_start = 0;
378 whitespace_sequence_length = 0;
379 }
380 current_offset += ch.len_utf8();
381 }
382 if whitespace_sequence_length >= 2 {
383 whitespace_sequences.push((whitespace_sequence_start, current_offset));
384 }
385
386 let closest_whitespace_end = if is_backward {
387 whitespace_sequences.last().map(|&(start, _)| start)
388 } else {
389 whitespace_sequences.first().map(|&(_, end)| end)
390 };
391
392 closest_whitespace_end
393 .unwrap_or_else(|| {
394 if is_backward {
395 trimmed_delete_range.start
396 } else {
397 trimmed_delete_range.end
398 }
399 })
400 .to_display_point(map)
401}
402
403/// Returns a position of the previous subword boundary, where a subword is defined as a run of
404/// word characters of the same "subkind" - where subcharacter kinds are '_' character,
405/// lowerspace characters and uppercase characters.
406pub fn previous_subword_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
407 let raw_point = point.to_point(map);
408 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
409
410 find_preceding_boundary_display_point(map, point, FindRange::MultiLine, |left, right| {
411 is_subword_start(left, right, &classifier) || left == '\n'
412 })
413}
414
415pub fn is_subword_start(left: char, right: char, classifier: &CharClassifier) -> bool {
416 let is_word_start = classifier.kind(left) != classifier.kind(right) && !right.is_whitespace();
417 let is_subword_start = classifier.is_word('-') && left == '-' && right != '-'
418 || left == '_' && right != '_'
419 || left.is_lowercase() && right.is_uppercase();
420 is_word_start || is_subword_start
421}
422
423/// Returns a position of the next word boundary, where a word character is defined as either
424/// uppercase letter, lowercase letter, '_' character or language-specific word character (like '-' in CSS).
425pub fn next_word_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
426 let raw_point = point.to_point(map);
427 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
428 let mut is_first_iteration = true;
429 find_boundary(map, point, FindRange::MultiLine, |left, right| {
430 // Make alt-right skip punctuation to respect VSCode behaviour. For example: |.hello goes to .hello|
431 if is_first_iteration
432 && classifier.is_punctuation(left)
433 && !classifier.is_punctuation(right)
434 && right != '\n'
435 {
436 is_first_iteration = false;
437 return false;
438 }
439 is_first_iteration = false;
440
441 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(left))
442 || right == '\n'
443 })
444}
445
446/// Returns a position of the next word boundary, where a word character is defined as either
447/// uppercase letter, lowercase letter, '_' character, language-specific word character (like '-' in CSS) or newline.
448pub fn next_word_end_or_newline(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
449 let raw_point = point.to_point(map);
450 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
451
452 let mut on_starting_row = true;
453 find_boundary(map, point, FindRange::MultiLine, |left, right| {
454 if left == '\n' {
455 on_starting_row = false;
456 }
457 (classifier.kind(left) != classifier.kind(right)
458 && ((on_starting_row && !left.is_whitespace())
459 || (!on_starting_row && !right.is_whitespace())))
460 || right == '\n'
461 })
462}
463
464/// Returns a position of the next subword boundary, where a subword is defined as a run of
465/// word characters of the same "subkind" - where subcharacter kinds are '_' character,
466/// lowerspace characters and uppercase characters.
467pub fn next_subword_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
468 let raw_point = point.to_point(map);
469 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
470
471 find_boundary(map, point, FindRange::MultiLine, |left, right| {
472 is_subword_end(left, right, &classifier) || right == '\n'
473 })
474}
475
476pub fn is_subword_end(left: char, right: char, classifier: &CharClassifier) -> bool {
477 let is_word_end =
478 (classifier.kind(left) != classifier.kind(right)) && !classifier.is_whitespace(left);
479 let is_subword_end = classifier.is_word('-') && left != '-' && right == '-'
480 || left != '_' && right == '_'
481 || left.is_lowercase() && right.is_uppercase();
482 is_word_end || is_subword_end
483}
484
485/// Returns a position of the start of the current paragraph, where a paragraph
486/// is defined as a run of non-blank lines.
487pub fn start_of_paragraph(
488 map: &DisplaySnapshot,
489 display_point: DisplayPoint,
490 mut count: usize,
491) -> DisplayPoint {
492 let point = display_point.to_point(map);
493 if point.row == 0 {
494 return DisplayPoint::zero();
495 }
496
497 let mut found_non_blank_line = false;
498 for row in (0..point.row + 1).rev() {
499 let blank = map.buffer_snapshot.is_line_blank(MultiBufferRow(row));
500 if found_non_blank_line && blank {
501 if count <= 1 {
502 return Point::new(row, 0).to_display_point(map);
503 }
504 count -= 1;
505 found_non_blank_line = false;
506 }
507
508 found_non_blank_line |= !blank;
509 }
510
511 DisplayPoint::zero()
512}
513
514/// Returns a position of the end of the current paragraph, where a paragraph
515/// is defined as a run of non-blank lines.
516pub fn end_of_paragraph(
517 map: &DisplaySnapshot,
518 display_point: DisplayPoint,
519 mut count: usize,
520) -> DisplayPoint {
521 let point = display_point.to_point(map);
522 if point.row == map.buffer_snapshot.max_row().0 {
523 return map.max_point();
524 }
525
526 let mut found_non_blank_line = false;
527 for row in point.row..=map.buffer_snapshot.max_row().0 {
528 let blank = map.buffer_snapshot.is_line_blank(MultiBufferRow(row));
529 if found_non_blank_line && blank {
530 if count <= 1 {
531 return Point::new(row, 0).to_display_point(map);
532 }
533 count -= 1;
534 found_non_blank_line = false;
535 }
536
537 found_non_blank_line |= !blank;
538 }
539
540 map.max_point()
541}
542
543pub fn start_of_excerpt(
544 map: &DisplaySnapshot,
545 display_point: DisplayPoint,
546 direction: Direction,
547) -> DisplayPoint {
548 let point = map.display_point_to_point(display_point, Bias::Left);
549 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point..point) else {
550 return display_point;
551 };
552 match direction {
553 Direction::Prev => {
554 let mut start = excerpt.start_anchor().to_display_point(map);
555 if start >= display_point && start.row() > DisplayRow(0) {
556 let Some(excerpt) = map.buffer_snapshot.excerpt_before(excerpt.id()) else {
557 return display_point;
558 };
559 start = excerpt.start_anchor().to_display_point(map);
560 }
561 start
562 }
563 Direction::Next => {
564 let mut end = excerpt.end_anchor().to_display_point(map);
565 *end.row_mut() += 1;
566 map.clip_point(end, Bias::Right)
567 }
568 }
569}
570
571pub fn end_of_excerpt(
572 map: &DisplaySnapshot,
573 display_point: DisplayPoint,
574 direction: Direction,
575) -> DisplayPoint {
576 let point = map.display_point_to_point(display_point, Bias::Left);
577 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point..point) else {
578 return display_point;
579 };
580 match direction {
581 Direction::Prev => {
582 let mut start = excerpt.start_anchor().to_display_point(map);
583 if start.row() > DisplayRow(0) {
584 *start.row_mut() -= 1;
585 }
586 start = map.clip_point(start, Bias::Left);
587 *start.column_mut() = 0;
588 start
589 }
590 Direction::Next => {
591 let mut end = excerpt.end_anchor().to_display_point(map);
592 *end.column_mut() = 0;
593 if end <= display_point {
594 *end.row_mut() += 1;
595 let point_end = map.display_point_to_point(end, Bias::Right);
596 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point_end..point_end)
597 else {
598 return display_point;
599 };
600 end = excerpt.end_anchor().to_display_point(map);
601 *end.column_mut() = 0;
602 }
603 end
604 }
605 }
606}
607
608/// Scans for a boundary preceding the given start point `from` until a boundary is found,
609/// indicated by the given predicate returning true.
610/// The predicate is called with the character to the left and right of the candidate boundary location.
611/// 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.
612pub fn find_preceding_boundary_point(
613 buffer_snapshot: &MultiBufferSnapshot,
614 from: Point,
615 find_range: FindRange,
616 mut is_boundary: impl FnMut(char, char) -> bool,
617) -> Point {
618 let mut prev_ch = None;
619 let mut offset = from.to_offset(buffer_snapshot);
620
621 for ch in buffer_snapshot.reversed_chars_at(offset) {
622 if find_range == FindRange::SingleLine && ch == '\n' {
623 break;
624 }
625 if let Some(prev_ch) = prev_ch
626 && is_boundary(ch, prev_ch)
627 {
628 break;
629 }
630
631 offset -= ch.len_utf8();
632 prev_ch = Some(ch);
633 }
634
635 offset.to_point(buffer_snapshot)
636}
637
638/// Scans for a boundary preceding the given start point `from` until a boundary is found,
639/// indicated by the given predicate returning true.
640/// The predicate is called with the character to the left and right of the candidate boundary location.
641/// 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.
642pub fn find_preceding_boundary_display_point(
643 map: &DisplaySnapshot,
644 from: DisplayPoint,
645 find_range: FindRange,
646 is_boundary: impl FnMut(char, char) -> bool,
647) -> DisplayPoint {
648 let result = find_preceding_boundary_point(
649 &map.buffer_snapshot,
650 from.to_point(map),
651 find_range,
652 is_boundary,
653 );
654 map.clip_point(result.to_display_point(map), Bias::Left)
655}
656
657/// Scans for a boundary following the given start point until a boundary is found, indicated by the
658/// given predicate returning true. The predicate is called with the character to the left and right
659/// of the candidate boundary location, and will be called with `\n` characters indicating the start
660/// or end of a line. The function supports optionally returning the point just before the boundary
661/// is found via return_point_before_boundary.
662pub fn find_boundary_point(
663 map: &DisplaySnapshot,
664 from: DisplayPoint,
665 find_range: FindRange,
666 mut is_boundary: impl FnMut(char, char) -> bool,
667 return_point_before_boundary: bool,
668) -> DisplayPoint {
669 let mut offset = from.to_offset(map, Bias::Right);
670 let mut prev_offset = offset;
671 let mut prev_ch = None;
672
673 for ch in map.buffer_snapshot.chars_at(offset) {
674 if find_range == FindRange::SingleLine && ch == '\n' {
675 break;
676 }
677 if let Some(prev_ch) = prev_ch
678 && is_boundary(prev_ch, ch)
679 {
680 if return_point_before_boundary {
681 return map.clip_point(prev_offset.to_display_point(map), Bias::Right);
682 } else {
683 break;
684 }
685 }
686 prev_offset = offset;
687 offset += ch.len_utf8();
688 prev_ch = Some(ch);
689 }
690 map.clip_point(offset.to_display_point(map), Bias::Right)
691}
692
693pub fn find_preceding_boundary_trail(
694 map: &DisplaySnapshot,
695 head: DisplayPoint,
696 mut is_boundary: impl FnMut(char, char) -> bool,
697) -> (Option<DisplayPoint>, DisplayPoint) {
698 let mut offset = head.to_offset(map, Bias::Left);
699 let mut trail_offset = None;
700
701 let mut prev_ch = map.buffer_snapshot.chars_at(offset).next();
702 let mut forward = map.buffer_snapshot.reversed_chars_at(offset).peekable();
703
704 // Skip newlines
705 while let Some(&ch) = forward.peek() {
706 if ch == '\n' {
707 prev_ch = forward.next();
708 offset -= ch.len_utf8();
709 trail_offset = Some(offset);
710 } else {
711 break;
712 }
713 }
714
715 // Find the boundary
716 let start_offset = offset;
717 for ch in forward {
718 if let Some(prev_ch) = prev_ch
719 && is_boundary(prev_ch, ch)
720 {
721 if start_offset == offset {
722 trail_offset = Some(offset);
723 } else {
724 break;
725 }
726 }
727 offset -= ch.len_utf8();
728 prev_ch = Some(ch);
729 }
730
731 let trail = trail_offset
732 .map(|trail_offset: usize| map.clip_point(trail_offset.to_display_point(map), Bias::Left));
733
734 (
735 trail,
736 map.clip_point(offset.to_display_point(map), Bias::Left),
737 )
738}
739
740/// Finds the location of a boundary
741pub fn find_boundary_trail(
742 map: &DisplaySnapshot,
743 head: DisplayPoint,
744 mut is_boundary: impl FnMut(char, char) -> bool,
745) -> (Option<DisplayPoint>, DisplayPoint) {
746 let mut offset = head.to_offset(map, Bias::Right);
747 let mut trail_offset = None;
748
749 let mut prev_ch = map.buffer_snapshot.reversed_chars_at(offset).next();
750 let mut forward = map.buffer_snapshot.chars_at(offset).peekable();
751
752 // Skip newlines
753 while let Some(&ch) = forward.peek() {
754 if ch == '\n' {
755 prev_ch = forward.next();
756 offset += ch.len_utf8();
757 trail_offset = Some(offset);
758 } else {
759 break;
760 }
761 }
762
763 // Find the boundary
764 let start_offset = offset;
765 for ch in forward {
766 if let Some(prev_ch) = prev_ch
767 && is_boundary(prev_ch, ch)
768 {
769 if start_offset == offset {
770 trail_offset = Some(offset);
771 } else {
772 break;
773 }
774 }
775 offset += ch.len_utf8();
776 prev_ch = Some(ch);
777 }
778
779 let trail = trail_offset
780 .map(|trail_offset: usize| map.clip_point(trail_offset.to_display_point(map), Bias::Right));
781
782 (
783 trail,
784 map.clip_point(offset.to_display_point(map), Bias::Right),
785 )
786}
787
788pub fn find_boundary(
789 map: &DisplaySnapshot,
790 from: DisplayPoint,
791 find_range: FindRange,
792 is_boundary: impl FnMut(char, char) -> bool,
793) -> DisplayPoint {
794 find_boundary_point(map, from, find_range, is_boundary, false)
795}
796
797pub fn find_boundary_exclusive(
798 map: &DisplaySnapshot,
799 from: DisplayPoint,
800 find_range: FindRange,
801 is_boundary: impl FnMut(char, char) -> bool,
802) -> DisplayPoint {
803 find_boundary_point(map, from, find_range, is_boundary, true)
804}
805
806/// Returns an iterator over the characters following a given offset in the [`DisplaySnapshot`].
807/// The returned value also contains a range of the start/end of a returned character in
808/// the [`DisplaySnapshot`]. The offsets are relative to the start of a buffer.
809pub fn chars_after(
810 map: &DisplaySnapshot,
811 mut offset: usize,
812) -> impl Iterator<Item = (char, Range<usize>)> + '_ {
813 map.buffer_snapshot.chars_at(offset).map(move |ch| {
814 let before = offset;
815 offset += ch.len_utf8();
816 (ch, before..offset)
817 })
818}
819
820/// Returns a reverse iterator over the characters following a given offset in the [`DisplaySnapshot`].
821/// The returned value also contains a range of the start/end of a returned character in
822/// the [`DisplaySnapshot`]. The offsets are relative to the start of a buffer.
823pub fn chars_before(
824 map: &DisplaySnapshot,
825 mut offset: usize,
826) -> impl Iterator<Item = (char, Range<usize>)> + '_ {
827 map.buffer_snapshot
828 .reversed_chars_at(offset)
829 .map(move |ch| {
830 let after = offset;
831 offset -= ch.len_utf8();
832 (ch, offset..after)
833 })
834}
835
836/// Returns a list of lines (represented as a [`DisplayPoint`] range) contained
837/// within a passed range.
838///
839/// The line ranges are **always* going to be in bounds of a requested range, which means that
840/// the first and the last lines might not necessarily represent the
841/// full range of a logical line (as their `.start`/`.end` values are clipped to those of a passed in range).
842pub fn split_display_range_by_lines(
843 map: &DisplaySnapshot,
844 range: Range<DisplayPoint>,
845) -> Vec<Range<DisplayPoint>> {
846 let mut result = Vec::new();
847
848 let mut start = range.start;
849 // Loop over all the covered rows until the one containing the range end
850 for row in range.start.row().0..range.end.row().0 {
851 let row_end_column = map.line_len(DisplayRow(row));
852 let end = map.clip_point(
853 DisplayPoint::new(DisplayRow(row), row_end_column),
854 Bias::Left,
855 );
856 if start != end {
857 result.push(start..end);
858 }
859 start = map.clip_point(DisplayPoint::new(DisplayRow(row + 1), 0), Bias::Left);
860 }
861
862 // Add the final range from the start of the last end to the original range end.
863 result.push(start..range.end);
864
865 result
866}
867
868#[cfg(test)]
869mod tests {
870 use super::*;
871 use crate::{
872 Buffer, DisplayMap, DisplayRow, ExcerptRange, FoldPlaceholder, MultiBuffer,
873 display_map::Inlay,
874 test::{editor_test_context::EditorTestContext, marked_display_snapshot},
875 };
876 use gpui::{AppContext as _, font, px};
877 use language::Capability;
878 use project::{Project, project_settings::DiagnosticSeverity};
879 use settings::SettingsStore;
880 use util::post_inc;
881
882 #[gpui::test]
883 fn test_previous_word_start(cx: &mut gpui::App) {
884 init_test(cx);
885
886 fn assert(marked_text: &str, cx: &mut gpui::App) {
887 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
888 let actual = previous_word_start(&snapshot, display_points[1]);
889 let expected = display_points[0];
890 if actual != expected {
891 eprintln!(
892 "previous_word_start mismatch for '{}': actual={:?}, expected={:?}",
893 marked_text, actual, expected
894 );
895 }
896 assert_eq!(actual, expected);
897 }
898
899 assert("\nˇ ˇlorem", cx);
900 assert("ˇ\nˇ lorem", cx);
901 assert(" ˇloremˇ", cx);
902 assert("ˇ ˇlorem", cx);
903 assert(" ˇlorˇem", cx);
904 assert("\nlorem\nˇ ˇipsum", cx);
905 assert("\n\nˇ\nˇ", cx);
906 assert(" ˇlorem ˇipsum", cx);
907 assert("ˇlorem-ˇipsum", cx);
908 assert("loremˇ-#$@ˇipsum", cx);
909 assert("ˇlorem_ˇipsum", cx);
910 assert(" ˇdefγˇ", cx);
911 assert(" ˇbcΔˇ", cx);
912 // Test punctuation skipping behavior
913 assert("ˇhello.ˇ", cx);
914 assert("helloˇ...ˇ", cx);
915 assert("helloˇ.---..ˇtest", cx);
916 assert("test ˇ.--ˇtest", cx);
917 assert("oneˇ,;:!?ˇtwo", cx);
918 }
919
920 #[gpui::test]
921 fn test_previous_subword_start(cx: &mut gpui::App) {
922 init_test(cx);
923
924 fn assert(marked_text: &str, cx: &mut gpui::App) {
925 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
926 assert_eq!(
927 previous_subword_start(&snapshot, display_points[1]),
928 display_points[0]
929 );
930 }
931
932 // Subword boundaries are respected
933 assert("lorem_ˇipˇsum", cx);
934 assert("lorem_ˇipsumˇ", cx);
935 assert("ˇlorem_ˇipsum", cx);
936 assert("lorem_ˇipsum_ˇdolor", cx);
937 assert("loremˇIpˇsum", cx);
938 assert("loremˇIpsumˇ", cx);
939
940 // Word boundaries are still respected
941 assert("\nˇ ˇlorem", cx);
942 assert(" ˇloremˇ", cx);
943 assert(" ˇlorˇem", cx);
944 assert("\nlorem\nˇ ˇipsum", cx);
945 assert("\n\nˇ\nˇ", cx);
946 assert(" ˇlorem ˇipsum", cx);
947 assert("loremˇ-ˇipsum", cx);
948 assert("loremˇ-#$@ˇipsum", cx);
949 assert(" ˇdefγˇ", cx);
950 assert(" bcˇΔˇ", cx);
951 assert(" ˇbcδˇ", cx);
952 assert(" abˇ——ˇcd", cx);
953 }
954
955 #[gpui::test]
956 fn test_find_preceding_boundary(cx: &mut gpui::App) {
957 init_test(cx);
958
959 fn assert(
960 marked_text: &str,
961 cx: &mut gpui::App,
962 is_boundary: impl FnMut(char, char) -> bool,
963 ) {
964 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
965 assert_eq!(
966 find_preceding_boundary_display_point(
967 &snapshot,
968 display_points[1],
969 FindRange::MultiLine,
970 is_boundary
971 ),
972 display_points[0]
973 );
974 }
975
976 assert("abcˇdef\ngh\nijˇk", cx, |left, right| {
977 left == 'c' && right == 'd'
978 });
979 assert("abcdef\nˇgh\nijˇk", cx, |left, right| {
980 left == '\n' && right == 'g'
981 });
982 let mut line_count = 0;
983 assert("abcdef\nˇgh\nijˇk", cx, |left, _| {
984 if left == '\n' {
985 line_count += 1;
986 line_count == 2
987 } else {
988 false
989 }
990 });
991 }
992
993 #[gpui::test]
994 fn test_find_preceding_boundary_with_inlays(cx: &mut gpui::App) {
995 init_test(cx);
996
997 let input_text = "abcdefghijklmnopqrstuvwxys";
998 let font = font("Helvetica");
999 let font_size = px(14.0);
1000 let buffer = MultiBuffer::build_simple(input_text, cx);
1001 let buffer_snapshot = buffer.read(cx).snapshot(cx);
1002
1003 let display_map = cx.new(|cx| {
1004 DisplayMap::new(
1005 buffer,
1006 font,
1007 font_size,
1008 None,
1009 1,
1010 1,
1011 FoldPlaceholder::test(),
1012 DiagnosticSeverity::Warning,
1013 cx,
1014 )
1015 });
1016
1017 // add all kinds of inlays between two word boundaries: we should be able to cross them all, when looking for another boundary
1018 let mut id = 0;
1019 let inlays = (0..buffer_snapshot.len())
1020 .flat_map(|offset| {
1021 [
1022 Inlay::edit_prediction(
1023 post_inc(&mut id),
1024 buffer_snapshot.anchor_before(offset),
1025 "test",
1026 ),
1027 Inlay::edit_prediction(
1028 post_inc(&mut id),
1029 buffer_snapshot.anchor_after(offset),
1030 "test",
1031 ),
1032 Inlay::mock_hint(
1033 post_inc(&mut id),
1034 buffer_snapshot.anchor_before(offset),
1035 "test",
1036 ),
1037 Inlay::mock_hint(
1038 post_inc(&mut id),
1039 buffer_snapshot.anchor_after(offset),
1040 "test",
1041 ),
1042 ]
1043 })
1044 .collect();
1045 let snapshot = display_map.update(cx, |map, cx| {
1046 map.splice_inlays(&[], inlays, cx);
1047 map.snapshot(cx)
1048 });
1049
1050 assert_eq!(
1051 find_preceding_boundary_display_point(
1052 &snapshot,
1053 buffer_snapshot.len().to_display_point(&snapshot),
1054 FindRange::MultiLine,
1055 |left, _| left == 'e',
1056 ),
1057 snapshot
1058 .buffer_snapshot
1059 .offset_to_point(5)
1060 .to_display_point(&snapshot),
1061 "Should not stop at inlays when looking for boundaries"
1062 );
1063 }
1064
1065 #[gpui::test]
1066 fn test_next_word_end(cx: &mut gpui::App) {
1067 init_test(cx);
1068
1069 fn assert(marked_text: &str, cx: &mut gpui::App) {
1070 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1071 let actual = next_word_end(&snapshot, display_points[0]);
1072 let expected = display_points[1];
1073 if actual != expected {
1074 eprintln!(
1075 "next_word_end mismatch for '{}': actual={:?}, expected={:?}",
1076 marked_text, actual, expected
1077 );
1078 }
1079 assert_eq!(actual, expected);
1080 }
1081
1082 assert("\nˇ loremˇ", cx);
1083 assert(" ˇloremˇ", cx);
1084 assert(" lorˇemˇ", cx);
1085 assert(" loremˇ ˇ\nipsum\n", cx);
1086 assert("\nˇ\nˇ\n\n", cx);
1087 assert("loremˇ ipsumˇ ", cx);
1088 assert("loremˇ-ipsumˇ", cx);
1089 assert("loremˇ#$@-ˇipsum", cx);
1090 assert("loremˇ_ipsumˇ", cx);
1091 assert(" ˇbcΔˇ", cx);
1092 assert(" abˇ——ˇcd", cx);
1093 // Test punctuation skipping behavior
1094 assert("ˇ.helloˇ", cx);
1095 assert("display_pointsˇ[0ˇ]", cx);
1096 assert("ˇ...ˇhello", cx);
1097 assert("helloˇ.---..ˇtest", cx);
1098 assert("testˇ.--ˇ test", cx);
1099 assert("oneˇ,;:!?ˇtwo", cx);
1100 }
1101
1102 #[gpui::test]
1103 fn test_next_subword_end(cx: &mut gpui::App) {
1104 init_test(cx);
1105
1106 fn assert(marked_text: &str, cx: &mut gpui::App) {
1107 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1108 assert_eq!(
1109 next_subword_end(&snapshot, display_points[0]),
1110 display_points[1]
1111 );
1112 }
1113
1114 // Subword boundaries are respected
1115 assert("loˇremˇ_ipsum", cx);
1116 assert("ˇloremˇ_ipsum", cx);
1117 assert("loremˇ_ipsumˇ", cx);
1118 assert("loremˇ_ipsumˇ_dolor", cx);
1119 assert("loˇremˇIpsum", cx);
1120 assert("loremˇIpsumˇDolor", cx);
1121
1122 // Word boundaries are still respected
1123 assert("\nˇ loremˇ", cx);
1124 assert(" ˇloremˇ", cx);
1125 assert(" lorˇemˇ", cx);
1126 assert(" loremˇ ˇ\nipsum\n", cx);
1127 assert("\nˇ\nˇ\n\n", cx);
1128 assert("loremˇ ipsumˇ ", cx);
1129 assert("loremˇ-ˇipsum", cx);
1130 assert("loremˇ#$@-ˇipsum", cx);
1131 assert("loremˇ_ipsumˇ", cx);
1132 assert(" ˇbcˇΔ", cx);
1133 assert(" abˇ——ˇcd", cx);
1134 }
1135
1136 #[gpui::test]
1137 fn test_find_boundary(cx: &mut gpui::App) {
1138 init_test(cx);
1139
1140 fn assert(
1141 marked_text: &str,
1142 cx: &mut gpui::App,
1143 is_boundary: impl FnMut(char, char) -> bool,
1144 ) {
1145 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1146 assert_eq!(
1147 find_boundary(
1148 &snapshot,
1149 display_points[0],
1150 FindRange::MultiLine,
1151 is_boundary,
1152 ),
1153 display_points[1]
1154 );
1155 }
1156
1157 assert("abcˇdef\ngh\nijˇk", cx, |left, right| {
1158 left == 'j' && right == 'k'
1159 });
1160 assert("abˇcdef\ngh\nˇijk", cx, |left, right| {
1161 left == '\n' && right == 'i'
1162 });
1163 let mut line_count = 0;
1164 assert("abcˇdef\ngh\nˇijk", cx, |left, _| {
1165 if left == '\n' {
1166 line_count += 1;
1167 line_count == 2
1168 } else {
1169 false
1170 }
1171 });
1172 }
1173
1174 #[gpui::test]
1175 async fn test_move_up_and_down_with_excerpts(cx: &mut gpui::TestAppContext) {
1176 cx.update(|cx| {
1177 init_test(cx);
1178 });
1179
1180 let mut cx = EditorTestContext::new(cx).await;
1181 let editor = cx.editor.clone();
1182 let window = cx.window;
1183 _ = cx.update_window(window, |_, window, cx| {
1184 let text_layout_details = editor.read(cx).text_layout_details(window);
1185
1186 let font = font("Helvetica");
1187
1188 let buffer = cx.new(|cx| Buffer::local("abc\ndefg\nhijkl\nmn", cx));
1189 let multibuffer = cx.new(|cx| {
1190 let mut multibuffer = MultiBuffer::new(Capability::ReadWrite);
1191 multibuffer.push_excerpts(
1192 buffer.clone(),
1193 [
1194 ExcerptRange::new(Point::new(0, 0)..Point::new(1, 4)),
1195 ExcerptRange::new(Point::new(2, 0)..Point::new(3, 2)),
1196 ],
1197 cx,
1198 );
1199 multibuffer
1200 });
1201 let display_map = cx.new(|cx| {
1202 DisplayMap::new(
1203 multibuffer,
1204 font,
1205 px(14.0),
1206 None,
1207 0,
1208 1,
1209 FoldPlaceholder::test(),
1210 DiagnosticSeverity::Warning,
1211 cx,
1212 )
1213 });
1214 let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
1215
1216 assert_eq!(snapshot.text(), "abc\ndefg\n\nhijkl\nmn");
1217
1218 let col_2_x = snapshot
1219 .x_for_display_point(DisplayPoint::new(DisplayRow(0), 2), &text_layout_details);
1220
1221 // Can't move up into the first excerpt's header
1222 assert_eq!(
1223 up(
1224 &snapshot,
1225 DisplayPoint::new(DisplayRow(0), 2),
1226 SelectionGoal::HorizontalPosition(f64::from(col_2_x)),
1227 false,
1228 &text_layout_details
1229 ),
1230 (
1231 DisplayPoint::new(DisplayRow(0), 0),
1232 SelectionGoal::HorizontalPosition(f64::from(col_2_x)),
1233 ),
1234 );
1235 assert_eq!(
1236 up(
1237 &snapshot,
1238 DisplayPoint::new(DisplayRow(0), 0),
1239 SelectionGoal::None,
1240 false,
1241 &text_layout_details
1242 ),
1243 (
1244 DisplayPoint::new(DisplayRow(0), 0),
1245 SelectionGoal::HorizontalPosition(0.0),
1246 ),
1247 );
1248
1249 let col_4_x = snapshot
1250 .x_for_display_point(DisplayPoint::new(DisplayRow(1), 4), &text_layout_details);
1251
1252 // Move up and down within first excerpt
1253 assert_eq!(
1254 up(
1255 &snapshot,
1256 DisplayPoint::new(DisplayRow(1), 4),
1257 SelectionGoal::HorizontalPosition(col_4_x.into()),
1258 false,
1259 &text_layout_details
1260 ),
1261 (
1262 DisplayPoint::new(DisplayRow(0), 3),
1263 SelectionGoal::HorizontalPosition(col_4_x.into())
1264 ),
1265 );
1266 assert_eq!(
1267 down(
1268 &snapshot,
1269 DisplayPoint::new(DisplayRow(0), 3),
1270 SelectionGoal::HorizontalPosition(col_4_x.into()),
1271 false,
1272 &text_layout_details
1273 ),
1274 (
1275 DisplayPoint::new(DisplayRow(1), 4),
1276 SelectionGoal::HorizontalPosition(col_4_x.into())
1277 ),
1278 );
1279
1280 let col_5_x = snapshot
1281 .x_for_display_point(DisplayPoint::new(DisplayRow(3), 5), &text_layout_details);
1282
1283 // Move up and down across second excerpt's header
1284 assert_eq!(
1285 up(
1286 &snapshot,
1287 DisplayPoint::new(DisplayRow(3), 5),
1288 SelectionGoal::HorizontalPosition(col_5_x.into()),
1289 false,
1290 &text_layout_details
1291 ),
1292 (
1293 DisplayPoint::new(DisplayRow(1), 4),
1294 SelectionGoal::HorizontalPosition(col_5_x.into())
1295 ),
1296 );
1297 assert_eq!(
1298 down(
1299 &snapshot,
1300 DisplayPoint::new(DisplayRow(1), 4),
1301 SelectionGoal::HorizontalPosition(col_5_x.into()),
1302 false,
1303 &text_layout_details
1304 ),
1305 (
1306 DisplayPoint::new(DisplayRow(3), 5),
1307 SelectionGoal::HorizontalPosition(col_5_x.into())
1308 ),
1309 );
1310
1311 let max_point_x = snapshot
1312 .x_for_display_point(DisplayPoint::new(DisplayRow(4), 2), &text_layout_details);
1313
1314 // Can't move down off the end, and attempting to do so leaves the selection goal unchanged
1315 assert_eq!(
1316 down(
1317 &snapshot,
1318 DisplayPoint::new(DisplayRow(4), 0),
1319 SelectionGoal::HorizontalPosition(0.0),
1320 false,
1321 &text_layout_details
1322 ),
1323 (
1324 DisplayPoint::new(DisplayRow(4), 2),
1325 SelectionGoal::HorizontalPosition(0.0)
1326 ),
1327 );
1328 assert_eq!(
1329 down(
1330 &snapshot,
1331 DisplayPoint::new(DisplayRow(4), 2),
1332 SelectionGoal::HorizontalPosition(max_point_x.into()),
1333 false,
1334 &text_layout_details
1335 ),
1336 (
1337 DisplayPoint::new(DisplayRow(4), 2),
1338 SelectionGoal::HorizontalPosition(max_point_x.into())
1339 ),
1340 );
1341 });
1342 }
1343
1344 fn init_test(cx: &mut gpui::App) {
1345 let settings_store = SettingsStore::test(cx);
1346 cx.set_global(settings_store);
1347 workspace::init_settings(cx);
1348 theme::init(theme::LoadThemes::JustBase, cx);
1349 language::init(cx);
1350 crate::init(cx);
1351 Project::init_settings(cx);
1352 }
1353}