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::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 let is_word_start =
409 classifier.kind(left) != classifier.kind(right) && !right.is_whitespace();
410 let is_subword_start = classifier.is_word('-') && left == '-' && right != '-'
411 || left == '_' && right != '_'
412 || left.is_lowercase() && right.is_uppercase();
413 is_word_start || is_subword_start || left == '\n'
414 })
415}
416
417/// Returns a position of the next word boundary, where a word character is defined as either
418/// uppercase letter, lowercase letter, '_' character or language-specific word character (like '-' in CSS).
419pub fn next_word_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
420 let raw_point = point.to_point(map);
421 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
422 let mut is_first_iteration = true;
423 find_boundary(map, point, FindRange::MultiLine, |left, right| {
424 // Make alt-right skip punctuation to respect VSCode behaviour. For example: |.hello goes to .hello|
425 if is_first_iteration
426 && classifier.is_punctuation(left)
427 && !classifier.is_punctuation(right)
428 && right != '\n'
429 {
430 is_first_iteration = false;
431 return false;
432 }
433 is_first_iteration = false;
434
435 (classifier.kind(left) != classifier.kind(right) && !classifier.is_whitespace(left))
436 || right == '\n'
437 })
438}
439
440/// Returns a position of the next word boundary, where a word character is defined as either
441/// uppercase letter, lowercase letter, '_' character, language-specific word character (like '-' in CSS) or newline.
442pub fn next_word_end_or_newline(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
443 let raw_point = point.to_point(map);
444 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
445
446 let mut on_starting_row = true;
447 find_boundary(map, point, FindRange::MultiLine, |left, right| {
448 if left == '\n' {
449 on_starting_row = false;
450 }
451 (classifier.kind(left) != classifier.kind(right)
452 && ((on_starting_row && !left.is_whitespace())
453 || (!on_starting_row && !right.is_whitespace())))
454 || right == '\n'
455 })
456}
457
458/// Returns a position of the next subword boundary, where a subword is defined as a run of
459/// word characters of the same "subkind" - where subcharacter kinds are '_' character,
460/// lowerspace characters and uppercase characters.
461pub fn next_subword_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
462 let raw_point = point.to_point(map);
463 let classifier = map.buffer_snapshot.char_classifier_at(raw_point);
464
465 find_boundary(map, point, FindRange::MultiLine, |left, right| {
466 let is_word_end =
467 (classifier.kind(left) != classifier.kind(right)) && !classifier.is_whitespace(left);
468 let is_subword_end = classifier.is_word('-') && left != '-' && right == '-'
469 || left != '_' && right == '_'
470 || left.is_lowercase() && right.is_uppercase();
471 is_word_end || is_subword_end || right == '\n'
472 })
473}
474
475/// Returns a position of the start of the current paragraph, where a paragraph
476/// is defined as a run of non-blank lines.
477pub fn start_of_paragraph(
478 map: &DisplaySnapshot,
479 display_point: DisplayPoint,
480 mut count: usize,
481) -> DisplayPoint {
482 let point = display_point.to_point(map);
483 if point.row == 0 {
484 return DisplayPoint::zero();
485 }
486
487 let mut found_non_blank_line = false;
488 for row in (0..point.row + 1).rev() {
489 let blank = map.buffer_snapshot.is_line_blank(MultiBufferRow(row));
490 if found_non_blank_line && blank {
491 if count <= 1 {
492 return Point::new(row, 0).to_display_point(map);
493 }
494 count -= 1;
495 found_non_blank_line = false;
496 }
497
498 found_non_blank_line |= !blank;
499 }
500
501 DisplayPoint::zero()
502}
503
504/// Returns a position of the end of the current paragraph, where a paragraph
505/// is defined as a run of non-blank lines.
506pub fn end_of_paragraph(
507 map: &DisplaySnapshot,
508 display_point: DisplayPoint,
509 mut count: usize,
510) -> DisplayPoint {
511 let point = display_point.to_point(map);
512 if point.row == map.buffer_snapshot.max_row().0 {
513 return map.max_point();
514 }
515
516 let mut found_non_blank_line = false;
517 for row in point.row..=map.buffer_snapshot.max_row().0 {
518 let blank = map.buffer_snapshot.is_line_blank(MultiBufferRow(row));
519 if found_non_blank_line && blank {
520 if count <= 1 {
521 return Point::new(row, 0).to_display_point(map);
522 }
523 count -= 1;
524 found_non_blank_line = false;
525 }
526
527 found_non_blank_line |= !blank;
528 }
529
530 map.max_point()
531}
532
533pub fn start_of_excerpt(
534 map: &DisplaySnapshot,
535 display_point: DisplayPoint,
536 direction: Direction,
537) -> DisplayPoint {
538 let point = map.display_point_to_point(display_point, Bias::Left);
539 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point..point) else {
540 return display_point;
541 };
542 match direction {
543 Direction::Prev => {
544 let mut start = excerpt.start_anchor().to_display_point(map);
545 if start >= display_point && start.row() > DisplayRow(0) {
546 let Some(excerpt) = map.buffer_snapshot.excerpt_before(excerpt.id()) else {
547 return display_point;
548 };
549 start = excerpt.start_anchor().to_display_point(map);
550 }
551 start
552 }
553 Direction::Next => {
554 let mut end = excerpt.end_anchor().to_display_point(map);
555 *end.row_mut() += 1;
556 map.clip_point(end, Bias::Right)
557 }
558 }
559}
560
561pub fn end_of_excerpt(
562 map: &DisplaySnapshot,
563 display_point: DisplayPoint,
564 direction: Direction,
565) -> DisplayPoint {
566 let point = map.display_point_to_point(display_point, Bias::Left);
567 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point..point) else {
568 return display_point;
569 };
570 match direction {
571 Direction::Prev => {
572 let mut start = excerpt.start_anchor().to_display_point(map);
573 if start.row() > DisplayRow(0) {
574 *start.row_mut() -= 1;
575 }
576 start = map.clip_point(start, Bias::Left);
577 *start.column_mut() = 0;
578 start
579 }
580 Direction::Next => {
581 let mut end = excerpt.end_anchor().to_display_point(map);
582 *end.column_mut() = 0;
583 if end <= display_point {
584 *end.row_mut() += 1;
585 let point_end = map.display_point_to_point(end, Bias::Right);
586 let Some(excerpt) = map.buffer_snapshot.excerpt_containing(point_end..point_end)
587 else {
588 return display_point;
589 };
590 end = excerpt.end_anchor().to_display_point(map);
591 *end.column_mut() = 0;
592 }
593 end
594 }
595 }
596}
597
598/// Scans for a boundary preceding the given start point `from` until a boundary is found,
599/// indicated by the given predicate returning true.
600/// The predicate is called with the character to the left and right of the candidate boundary location.
601/// 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.
602pub fn find_preceding_boundary_point(
603 buffer_snapshot: &MultiBufferSnapshot,
604 from: Point,
605 find_range: FindRange,
606 mut is_boundary: impl FnMut(char, char) -> bool,
607) -> Point {
608 let mut prev_ch = None;
609 let mut offset = from.to_offset(buffer_snapshot);
610
611 for ch in buffer_snapshot.reversed_chars_at(offset) {
612 if find_range == FindRange::SingleLine && ch == '\n' {
613 break;
614 }
615 if let Some(prev_ch) = prev_ch
616 && is_boundary(ch, prev_ch)
617 {
618 break;
619 }
620
621 offset -= ch.len_utf8();
622 prev_ch = Some(ch);
623 }
624
625 offset.to_point(buffer_snapshot)
626}
627
628/// Scans for a boundary preceding the given start point `from` until a boundary is found,
629/// indicated by the given predicate returning true.
630/// The predicate is called with the character to the left and right of the candidate boundary location.
631/// 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.
632pub fn find_preceding_boundary_display_point(
633 map: &DisplaySnapshot,
634 from: DisplayPoint,
635 find_range: FindRange,
636 is_boundary: impl FnMut(char, char) -> bool,
637) -> DisplayPoint {
638 let result = find_preceding_boundary_point(
639 &map.buffer_snapshot,
640 from.to_point(map),
641 find_range,
642 is_boundary,
643 );
644 map.clip_point(result.to_display_point(map), Bias::Left)
645}
646
647/// Scans for a boundary following the given start point until a boundary is found, indicated by the
648/// given predicate returning true. The predicate is called with the character to the left and right
649/// of the candidate boundary location, and will be called with `\n` characters indicating the start
650/// or end of a line. The function supports optionally returning the point just before the boundary
651/// is found via return_point_before_boundary.
652pub fn find_boundary_point(
653 map: &DisplaySnapshot,
654 from: DisplayPoint,
655 find_range: FindRange,
656 mut is_boundary: impl FnMut(char, char) -> bool,
657 return_point_before_boundary: bool,
658) -> DisplayPoint {
659 let mut offset = from.to_offset(map, Bias::Right);
660 let mut prev_offset = offset;
661 let mut prev_ch = None;
662
663 for ch in map.buffer_snapshot.chars_at(offset) {
664 if find_range == FindRange::SingleLine && ch == '\n' {
665 break;
666 }
667 if let Some(prev_ch) = prev_ch
668 && is_boundary(prev_ch, ch)
669 {
670 if return_point_before_boundary {
671 return map.clip_point(prev_offset.to_display_point(map), Bias::Right);
672 } else {
673 break;
674 }
675 }
676 prev_offset = offset;
677 offset += ch.len_utf8();
678 prev_ch = Some(ch);
679 }
680 map.clip_point(offset.to_display_point(map), Bias::Right)
681}
682
683pub fn find_preceding_boundary_trail(
684 map: &DisplaySnapshot,
685 head: DisplayPoint,
686 mut is_boundary: impl FnMut(char, char) -> bool,
687) -> (Option<DisplayPoint>, DisplayPoint) {
688 let mut offset = head.to_offset(map, Bias::Left);
689 let mut trail_offset = None;
690
691 let mut prev_ch = map.buffer_snapshot.chars_at(offset).next();
692 let mut forward = map.buffer_snapshot.reversed_chars_at(offset).peekable();
693
694 // Skip newlines
695 while let Some(&ch) = forward.peek() {
696 if ch == '\n' {
697 prev_ch = forward.next();
698 offset -= ch.len_utf8();
699 trail_offset = Some(offset);
700 } else {
701 break;
702 }
703 }
704
705 // Find the boundary
706 let start_offset = offset;
707 for ch in forward {
708 if let Some(prev_ch) = prev_ch
709 && is_boundary(prev_ch, ch)
710 {
711 if start_offset == offset {
712 trail_offset = Some(offset);
713 } else {
714 break;
715 }
716 }
717 offset -= ch.len_utf8();
718 prev_ch = Some(ch);
719 }
720
721 let trail = trail_offset
722 .map(|trail_offset: usize| map.clip_point(trail_offset.to_display_point(map), Bias::Left));
723
724 (
725 trail,
726 map.clip_point(offset.to_display_point(map), Bias::Left),
727 )
728}
729
730/// Finds the location of a boundary
731pub fn find_boundary_trail(
732 map: &DisplaySnapshot,
733 head: DisplayPoint,
734 mut is_boundary: impl FnMut(char, char) -> bool,
735) -> (Option<DisplayPoint>, DisplayPoint) {
736 let mut offset = head.to_offset(map, Bias::Right);
737 let mut trail_offset = None;
738
739 let mut prev_ch = map.buffer_snapshot.reversed_chars_at(offset).next();
740 let mut forward = map.buffer_snapshot.chars_at(offset).peekable();
741
742 // Skip newlines
743 while let Some(&ch) = forward.peek() {
744 if ch == '\n' {
745 prev_ch = forward.next();
746 offset += ch.len_utf8();
747 trail_offset = Some(offset);
748 } else {
749 break;
750 }
751 }
752
753 // Find the boundary
754 let start_offset = offset;
755 for ch in forward {
756 if let Some(prev_ch) = prev_ch
757 && is_boundary(prev_ch, ch)
758 {
759 if start_offset == offset {
760 trail_offset = Some(offset);
761 } else {
762 break;
763 }
764 }
765 offset += ch.len_utf8();
766 prev_ch = Some(ch);
767 }
768
769 let trail = trail_offset
770 .map(|trail_offset: usize| map.clip_point(trail_offset.to_display_point(map), Bias::Right));
771
772 (
773 trail,
774 map.clip_point(offset.to_display_point(map), Bias::Right),
775 )
776}
777
778pub fn find_boundary(
779 map: &DisplaySnapshot,
780 from: DisplayPoint,
781 find_range: FindRange,
782 is_boundary: impl FnMut(char, char) -> bool,
783) -> DisplayPoint {
784 find_boundary_point(map, from, find_range, is_boundary, false)
785}
786
787pub fn find_boundary_exclusive(
788 map: &DisplaySnapshot,
789 from: DisplayPoint,
790 find_range: FindRange,
791 is_boundary: impl FnMut(char, char) -> bool,
792) -> DisplayPoint {
793 find_boundary_point(map, from, find_range, is_boundary, true)
794}
795
796/// Returns an iterator over the characters following a given offset in the [`DisplaySnapshot`].
797/// The returned value also contains a range of the start/end of a returned character in
798/// the [`DisplaySnapshot`]. The offsets are relative to the start of a buffer.
799pub fn chars_after(
800 map: &DisplaySnapshot,
801 mut offset: usize,
802) -> impl Iterator<Item = (char, Range<usize>)> + '_ {
803 map.buffer_snapshot.chars_at(offset).map(move |ch| {
804 let before = offset;
805 offset += ch.len_utf8();
806 (ch, before..offset)
807 })
808}
809
810/// Returns a reverse iterator over the characters following a given offset in the [`DisplaySnapshot`].
811/// The returned value also contains a range of the start/end of a returned character in
812/// the [`DisplaySnapshot`]. The offsets are relative to the start of a buffer.
813pub fn chars_before(
814 map: &DisplaySnapshot,
815 mut offset: usize,
816) -> impl Iterator<Item = (char, Range<usize>)> + '_ {
817 map.buffer_snapshot
818 .reversed_chars_at(offset)
819 .map(move |ch| {
820 let after = offset;
821 offset -= ch.len_utf8();
822 (ch, offset..after)
823 })
824}
825
826/// Returns a list of lines (represented as a [`DisplayPoint`] range) contained
827/// within a passed range.
828///
829/// The line ranges are **always* going to be in bounds of a requested range, which means that
830/// the first and the last lines might not necessarily represent the
831/// full range of a logical line (as their `.start`/`.end` values are clipped to those of a passed in range).
832pub fn split_display_range_by_lines(
833 map: &DisplaySnapshot,
834 range: Range<DisplayPoint>,
835) -> Vec<Range<DisplayPoint>> {
836 let mut result = Vec::new();
837
838 let mut start = range.start;
839 // Loop over all the covered rows until the one containing the range end
840 for row in range.start.row().0..range.end.row().0 {
841 let row_end_column = map.line_len(DisplayRow(row));
842 let end = map.clip_point(
843 DisplayPoint::new(DisplayRow(row), row_end_column),
844 Bias::Left,
845 );
846 if start != end {
847 result.push(start..end);
848 }
849 start = map.clip_point(DisplayPoint::new(DisplayRow(row + 1), 0), Bias::Left);
850 }
851
852 // Add the final range from the start of the last end to the original range end.
853 result.push(start..range.end);
854
855 result
856}
857
858#[cfg(test)]
859mod tests {
860 use super::*;
861 use crate::{
862 Buffer, DisplayMap, DisplayRow, ExcerptRange, FoldPlaceholder, MultiBuffer,
863 display_map::Inlay,
864 test::{editor_test_context::EditorTestContext, marked_display_snapshot},
865 };
866 use gpui::{AppContext as _, font, px};
867 use language::Capability;
868 use project::{Project, project_settings::DiagnosticSeverity};
869 use settings::SettingsStore;
870 use util::post_inc;
871
872 #[gpui::test]
873 fn test_previous_word_start(cx: &mut gpui::App) {
874 init_test(cx);
875
876 fn assert(marked_text: &str, cx: &mut gpui::App) {
877 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
878 let actual = previous_word_start(&snapshot, display_points[1]);
879 let expected = display_points[0];
880 if actual != expected {
881 eprintln!(
882 "previous_word_start mismatch for '{}': actual={:?}, expected={:?}",
883 marked_text, actual, expected
884 );
885 }
886 assert_eq!(actual, expected);
887 }
888
889 assert("\nˇ ˇlorem", cx);
890 assert("ˇ\nˇ lorem", cx);
891 assert(" ˇloremˇ", cx);
892 assert("ˇ ˇlorem", cx);
893 assert(" ˇlorˇem", cx);
894 assert("\nlorem\nˇ ˇipsum", cx);
895 assert("\n\nˇ\nˇ", cx);
896 assert(" ˇlorem ˇipsum", cx);
897 assert("ˇlorem-ˇipsum", cx);
898 assert("loremˇ-#$@ˇipsum", cx);
899 assert("ˇlorem_ˇipsum", cx);
900 assert(" ˇdefγˇ", cx);
901 assert(" ˇbcΔˇ", cx);
902 // Test punctuation skipping behavior
903 assert("ˇhello.ˇ", cx);
904 assert("helloˇ...ˇ", cx);
905 assert("helloˇ.---..ˇtest", cx);
906 assert("test ˇ.--ˇtest", cx);
907 assert("oneˇ,;:!?ˇtwo", cx);
908 }
909
910 #[gpui::test]
911 fn test_previous_subword_start(cx: &mut gpui::App) {
912 init_test(cx);
913
914 fn assert(marked_text: &str, cx: &mut gpui::App) {
915 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
916 assert_eq!(
917 previous_subword_start(&snapshot, display_points[1]),
918 display_points[0]
919 );
920 }
921
922 // Subword boundaries are respected
923 assert("lorem_ˇipˇsum", cx);
924 assert("lorem_ˇipsumˇ", cx);
925 assert("ˇlorem_ˇipsum", cx);
926 assert("lorem_ˇipsum_ˇdolor", cx);
927 assert("loremˇIpˇsum", cx);
928 assert("loremˇIpsumˇ", cx);
929
930 // Word boundaries are still respected
931 assert("\nˇ ˇlorem", cx);
932 assert(" ˇloremˇ", cx);
933 assert(" ˇlorˇem", cx);
934 assert("\nlorem\nˇ ˇipsum", cx);
935 assert("\n\nˇ\nˇ", cx);
936 assert(" ˇlorem ˇipsum", cx);
937 assert("loremˇ-ˇipsum", cx);
938 assert("loremˇ-#$@ˇipsum", cx);
939 assert(" ˇdefγˇ", cx);
940 assert(" bcˇΔˇ", cx);
941 assert(" ˇbcδˇ", cx);
942 assert(" abˇ——ˇcd", cx);
943 }
944
945 #[gpui::test]
946 fn test_find_preceding_boundary(cx: &mut gpui::App) {
947 init_test(cx);
948
949 fn assert(
950 marked_text: &str,
951 cx: &mut gpui::App,
952 is_boundary: impl FnMut(char, char) -> bool,
953 ) {
954 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
955 assert_eq!(
956 find_preceding_boundary_display_point(
957 &snapshot,
958 display_points[1],
959 FindRange::MultiLine,
960 is_boundary
961 ),
962 display_points[0]
963 );
964 }
965
966 assert("abcˇdef\ngh\nijˇk", cx, |left, right| {
967 left == 'c' && right == 'd'
968 });
969 assert("abcdef\nˇgh\nijˇk", cx, |left, right| {
970 left == '\n' && right == 'g'
971 });
972 let mut line_count = 0;
973 assert("abcdef\nˇgh\nijˇk", cx, |left, _| {
974 if left == '\n' {
975 line_count += 1;
976 line_count == 2
977 } else {
978 false
979 }
980 });
981 }
982
983 #[gpui::test]
984 fn test_find_preceding_boundary_with_inlays(cx: &mut gpui::App) {
985 init_test(cx);
986
987 let input_text = "abcdefghijklmnopqrstuvwxys";
988 let font = font("Helvetica");
989 let font_size = px(14.0);
990 let buffer = MultiBuffer::build_simple(input_text, cx);
991 let buffer_snapshot = buffer.read(cx).snapshot(cx);
992
993 let display_map = cx.new(|cx| {
994 DisplayMap::new(
995 buffer,
996 font,
997 font_size,
998 None,
999 1,
1000 1,
1001 FoldPlaceholder::test(),
1002 DiagnosticSeverity::Warning,
1003 cx,
1004 )
1005 });
1006
1007 // add all kinds of inlays between two word boundaries: we should be able to cross them all, when looking for another boundary
1008 let mut id = 0;
1009 let inlays = (0..buffer_snapshot.len())
1010 .flat_map(|offset| {
1011 [
1012 Inlay::edit_prediction(
1013 post_inc(&mut id),
1014 buffer_snapshot.anchor_at(offset, Bias::Left),
1015 "test",
1016 ),
1017 Inlay::edit_prediction(
1018 post_inc(&mut id),
1019 buffer_snapshot.anchor_at(offset, Bias::Right),
1020 "test",
1021 ),
1022 Inlay::mock_hint(
1023 post_inc(&mut id),
1024 buffer_snapshot.anchor_at(offset, Bias::Left),
1025 "test",
1026 ),
1027 Inlay::mock_hint(
1028 post_inc(&mut id),
1029 buffer_snapshot.anchor_at(offset, Bias::Right),
1030 "test",
1031 ),
1032 ]
1033 })
1034 .collect();
1035 let snapshot = display_map.update(cx, |map, cx| {
1036 map.splice_inlays(&[], inlays, cx);
1037 map.snapshot(cx)
1038 });
1039
1040 assert_eq!(
1041 find_preceding_boundary_display_point(
1042 &snapshot,
1043 buffer_snapshot.len().to_display_point(&snapshot),
1044 FindRange::MultiLine,
1045 |left, _| left == 'e',
1046 ),
1047 snapshot
1048 .buffer_snapshot
1049 .offset_to_point(5)
1050 .to_display_point(&snapshot),
1051 "Should not stop at inlays when looking for boundaries"
1052 );
1053 }
1054
1055 #[gpui::test]
1056 fn test_next_word_end(cx: &mut gpui::App) {
1057 init_test(cx);
1058
1059 fn assert(marked_text: &str, cx: &mut gpui::App) {
1060 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1061 let actual = next_word_end(&snapshot, display_points[0]);
1062 let expected = display_points[1];
1063 if actual != expected {
1064 eprintln!(
1065 "next_word_end mismatch for '{}': actual={:?}, expected={:?}",
1066 marked_text, actual, expected
1067 );
1068 }
1069 assert_eq!(actual, expected);
1070 }
1071
1072 assert("\nˇ loremˇ", cx);
1073 assert(" ˇloremˇ", cx);
1074 assert(" lorˇemˇ", cx);
1075 assert(" loremˇ ˇ\nipsum\n", cx);
1076 assert("\nˇ\nˇ\n\n", cx);
1077 assert("loremˇ ipsumˇ ", cx);
1078 assert("loremˇ-ipsumˇ", cx);
1079 assert("loremˇ#$@-ˇipsum", cx);
1080 assert("loremˇ_ipsumˇ", cx);
1081 assert(" ˇbcΔˇ", cx);
1082 assert(" abˇ——ˇcd", cx);
1083 // Test punctuation skipping behavior
1084 assert("ˇ.helloˇ", cx);
1085 assert("display_pointsˇ[0ˇ]", cx);
1086 assert("ˇ...ˇhello", cx);
1087 assert("helloˇ.---..ˇtest", cx);
1088 assert("testˇ.--ˇ test", cx);
1089 assert("oneˇ,;:!?ˇtwo", cx);
1090 }
1091
1092 #[gpui::test]
1093 fn test_next_subword_end(cx: &mut gpui::App) {
1094 init_test(cx);
1095
1096 fn assert(marked_text: &str, cx: &mut gpui::App) {
1097 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1098 assert_eq!(
1099 next_subword_end(&snapshot, display_points[0]),
1100 display_points[1]
1101 );
1102 }
1103
1104 // Subword boundaries are respected
1105 assert("loˇremˇ_ipsum", cx);
1106 assert("ˇloremˇ_ipsum", cx);
1107 assert("loremˇ_ipsumˇ", cx);
1108 assert("loremˇ_ipsumˇ_dolor", cx);
1109 assert("loˇremˇIpsum", cx);
1110 assert("loremˇIpsumˇDolor", cx);
1111
1112 // Word boundaries are still respected
1113 assert("\nˇ loremˇ", cx);
1114 assert(" ˇloremˇ", cx);
1115 assert(" lorˇemˇ", cx);
1116 assert(" loremˇ ˇ\nipsum\n", cx);
1117 assert("\nˇ\nˇ\n\n", cx);
1118 assert("loremˇ ipsumˇ ", cx);
1119 assert("loremˇ-ˇipsum", cx);
1120 assert("loremˇ#$@-ˇipsum", cx);
1121 assert("loremˇ_ipsumˇ", cx);
1122 assert(" ˇbcˇΔ", cx);
1123 assert(" abˇ——ˇcd", cx);
1124 }
1125
1126 #[gpui::test]
1127 fn test_find_boundary(cx: &mut gpui::App) {
1128 init_test(cx);
1129
1130 fn assert(
1131 marked_text: &str,
1132 cx: &mut gpui::App,
1133 is_boundary: impl FnMut(char, char) -> bool,
1134 ) {
1135 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
1136 assert_eq!(
1137 find_boundary(
1138 &snapshot,
1139 display_points[0],
1140 FindRange::MultiLine,
1141 is_boundary,
1142 ),
1143 display_points[1]
1144 );
1145 }
1146
1147 assert("abcˇdef\ngh\nijˇk", cx, |left, right| {
1148 left == 'j' && right == 'k'
1149 });
1150 assert("abˇcdef\ngh\nˇijk", cx, |left, right| {
1151 left == '\n' && right == 'i'
1152 });
1153 let mut line_count = 0;
1154 assert("abcˇdef\ngh\nˇijk", cx, |left, _| {
1155 if left == '\n' {
1156 line_count += 1;
1157 line_count == 2
1158 } else {
1159 false
1160 }
1161 });
1162 }
1163
1164 #[gpui::test]
1165 async fn test_move_up_and_down_with_excerpts(cx: &mut gpui::TestAppContext) {
1166 cx.update(|cx| {
1167 init_test(cx);
1168 });
1169
1170 let mut cx = EditorTestContext::new(cx).await;
1171 let editor = cx.editor.clone();
1172 let window = cx.window;
1173 _ = cx.update_window(window, |_, window, cx| {
1174 let text_layout_details = editor.read(cx).text_layout_details(window);
1175
1176 let font = font("Helvetica");
1177
1178 let buffer = cx.new(|cx| Buffer::local("abc\ndefg\nhijkl\nmn", cx));
1179 let multibuffer = cx.new(|cx| {
1180 let mut multibuffer = MultiBuffer::new(Capability::ReadWrite);
1181 multibuffer.push_excerpts(
1182 buffer.clone(),
1183 [
1184 ExcerptRange::new(Point::new(0, 0)..Point::new(1, 4)),
1185 ExcerptRange::new(Point::new(2, 0)..Point::new(3, 2)),
1186 ],
1187 cx,
1188 );
1189 multibuffer
1190 });
1191 let display_map = cx.new(|cx| {
1192 DisplayMap::new(
1193 multibuffer,
1194 font,
1195 px(14.0),
1196 None,
1197 0,
1198 1,
1199 FoldPlaceholder::test(),
1200 DiagnosticSeverity::Warning,
1201 cx,
1202 )
1203 });
1204 let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
1205
1206 assert_eq!(snapshot.text(), "abc\ndefg\n\nhijkl\nmn");
1207
1208 let col_2_x = snapshot
1209 .x_for_display_point(DisplayPoint::new(DisplayRow(0), 2), &text_layout_details);
1210
1211 // Can't move up into the first excerpt's header
1212 assert_eq!(
1213 up(
1214 &snapshot,
1215 DisplayPoint::new(DisplayRow(0), 2),
1216 SelectionGoal::HorizontalPosition(col_2_x.0),
1217 false,
1218 &text_layout_details
1219 ),
1220 (
1221 DisplayPoint::new(DisplayRow(0), 0),
1222 SelectionGoal::HorizontalPosition(col_2_x.0),
1223 ),
1224 );
1225 assert_eq!(
1226 up(
1227 &snapshot,
1228 DisplayPoint::new(DisplayRow(0), 0),
1229 SelectionGoal::None,
1230 false,
1231 &text_layout_details
1232 ),
1233 (
1234 DisplayPoint::new(DisplayRow(0), 0),
1235 SelectionGoal::HorizontalPosition(0.0),
1236 ),
1237 );
1238
1239 let col_4_x = snapshot
1240 .x_for_display_point(DisplayPoint::new(DisplayRow(1), 4), &text_layout_details);
1241
1242 // Move up and down within first excerpt
1243 assert_eq!(
1244 up(
1245 &snapshot,
1246 DisplayPoint::new(DisplayRow(1), 4),
1247 SelectionGoal::HorizontalPosition(col_4_x.0),
1248 false,
1249 &text_layout_details
1250 ),
1251 (
1252 DisplayPoint::new(DisplayRow(0), 3),
1253 SelectionGoal::HorizontalPosition(col_4_x.0)
1254 ),
1255 );
1256 assert_eq!(
1257 down(
1258 &snapshot,
1259 DisplayPoint::new(DisplayRow(0), 3),
1260 SelectionGoal::HorizontalPosition(col_4_x.0),
1261 false,
1262 &text_layout_details
1263 ),
1264 (
1265 DisplayPoint::new(DisplayRow(1), 4),
1266 SelectionGoal::HorizontalPosition(col_4_x.0)
1267 ),
1268 );
1269
1270 let col_5_x = snapshot
1271 .x_for_display_point(DisplayPoint::new(DisplayRow(3), 5), &text_layout_details);
1272
1273 // Move up and down across second excerpt's header
1274 assert_eq!(
1275 up(
1276 &snapshot,
1277 DisplayPoint::new(DisplayRow(3), 5),
1278 SelectionGoal::HorizontalPosition(col_5_x.0),
1279 false,
1280 &text_layout_details
1281 ),
1282 (
1283 DisplayPoint::new(DisplayRow(1), 4),
1284 SelectionGoal::HorizontalPosition(col_5_x.0)
1285 ),
1286 );
1287 assert_eq!(
1288 down(
1289 &snapshot,
1290 DisplayPoint::new(DisplayRow(1), 4),
1291 SelectionGoal::HorizontalPosition(col_5_x.0),
1292 false,
1293 &text_layout_details
1294 ),
1295 (
1296 DisplayPoint::new(DisplayRow(3), 5),
1297 SelectionGoal::HorizontalPosition(col_5_x.0)
1298 ),
1299 );
1300
1301 let max_point_x = snapshot
1302 .x_for_display_point(DisplayPoint::new(DisplayRow(4), 2), &text_layout_details);
1303
1304 // Can't move down off the end, and attempting to do so leaves the selection goal unchanged
1305 assert_eq!(
1306 down(
1307 &snapshot,
1308 DisplayPoint::new(DisplayRow(4), 0),
1309 SelectionGoal::HorizontalPosition(0.0),
1310 false,
1311 &text_layout_details
1312 ),
1313 (
1314 DisplayPoint::new(DisplayRow(4), 2),
1315 SelectionGoal::HorizontalPosition(0.0)
1316 ),
1317 );
1318 assert_eq!(
1319 down(
1320 &snapshot,
1321 DisplayPoint::new(DisplayRow(4), 2),
1322 SelectionGoal::HorizontalPosition(max_point_x.0),
1323 false,
1324 &text_layout_details
1325 ),
1326 (
1327 DisplayPoint::new(DisplayRow(4), 2),
1328 SelectionGoal::HorizontalPosition(max_point_x.0)
1329 ),
1330 );
1331 });
1332 }
1333
1334 fn init_test(cx: &mut gpui::App) {
1335 let settings_store = SettingsStore::test(cx);
1336 cx.set_global(settings_store);
1337 workspace::init_settings(cx);
1338 theme::init(theme::LoadThemes::JustBase, cx);
1339 language::init(cx);
1340 crate::init(cx);
1341 Project::init_settings(cx);
1342 }
1343}