1use super::{Bias, DisplayPoint, DisplaySnapshot, SelectionGoal, ToDisplayPoint};
2use crate::{char_kind, CharKind, ToPoint};
3use language::Point;
4use std::ops::Range;
5
6pub fn left(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
7 if point.column() > 0 {
8 *point.column_mut() -= 1;
9 } else if point.row() > 0 {
10 *point.row_mut() -= 1;
11 *point.column_mut() = map.line_len(point.row());
12 }
13 map.clip_point(point, Bias::Left)
14}
15
16pub fn right(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
17 let max_column = map.line_len(point.row());
18 if point.column() < max_column {
19 *point.column_mut() += 1;
20 } else if point.row() < map.max_point().row() {
21 *point.row_mut() += 1;
22 *point.column_mut() = 0;
23 }
24 map.clip_point(point, Bias::Right)
25}
26
27pub fn up(
28 map: &DisplaySnapshot,
29 start: DisplayPoint,
30 goal: SelectionGoal,
31) -> (DisplayPoint, SelectionGoal) {
32 let mut goal_column = if let SelectionGoal::Column(column) = goal {
33 column
34 } else {
35 map.column_to_chars(start.row(), start.column())
36 };
37
38 let prev_row = start.row().saturating_sub(1);
39 let mut point = map.clip_point(
40 DisplayPoint::new(prev_row, map.line_len(prev_row)),
41 Bias::Left,
42 );
43 if point.row() < start.row() {
44 *point.column_mut() = map.column_from_chars(point.row(), goal_column);
45 } else {
46 point = DisplayPoint::new(0, 0);
47 goal_column = 0;
48 }
49
50 let clip_bias = if point.column() == map.line_len(point.row()) {
51 Bias::Left
52 } else {
53 Bias::Right
54 };
55
56 (
57 map.clip_point(point, clip_bias),
58 SelectionGoal::Column(goal_column),
59 )
60}
61
62pub fn down(
63 map: &DisplaySnapshot,
64 start: DisplayPoint,
65 goal: SelectionGoal,
66) -> (DisplayPoint, SelectionGoal) {
67 let mut goal_column = if let SelectionGoal::Column(column) = goal {
68 column
69 } else {
70 map.column_to_chars(start.row(), start.column())
71 };
72
73 let next_row = start.row() + 1;
74 let mut point = map.clip_point(DisplayPoint::new(next_row, 0), Bias::Right);
75 if point.row() > start.row() {
76 *point.column_mut() = map.column_from_chars(point.row(), goal_column);
77 } else {
78 point = map.max_point();
79 goal_column = map.column_to_chars(point.row(), point.column())
80 }
81
82 let clip_bias = if point.column() == map.line_len(point.row()) {
83 Bias::Left
84 } else {
85 Bias::Right
86 };
87
88 (
89 map.clip_point(point, clip_bias),
90 SelectionGoal::Column(goal_column),
91 )
92}
93
94pub fn line_beginning(
95 map: &DisplaySnapshot,
96 display_point: DisplayPoint,
97 stop_at_soft_boundaries: bool,
98) -> DisplayPoint {
99 let point = display_point.to_point(map);
100 let soft_line_start = map.clip_point(DisplayPoint::new(display_point.row(), 0), Bias::Right);
101 let indent_start = Point::new(
102 point.row,
103 map.buffer_snapshot.indent_column_for_line(point.row),
104 )
105 .to_display_point(map);
106 let line_start = map.prev_line_boundary(point).1;
107
108 if stop_at_soft_boundaries && soft_line_start > indent_start && display_point != soft_line_start
109 {
110 soft_line_start
111 } else if stop_at_soft_boundaries && display_point != indent_start {
112 indent_start
113 } else {
114 line_start
115 }
116}
117
118pub fn line_end(
119 map: &DisplaySnapshot,
120 display_point: DisplayPoint,
121 stop_at_soft_boundaries: bool,
122) -> DisplayPoint {
123 let soft_line_end = map.clip_point(
124 DisplayPoint::new(display_point.row(), map.line_len(display_point.row())),
125 Bias::Left,
126 );
127 if stop_at_soft_boundaries && display_point != soft_line_end {
128 soft_line_end
129 } else {
130 map.next_line_boundary(display_point.to_point(map)).1
131 }
132}
133
134pub fn previous_word_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
135 find_preceding_boundary(map, point, |left, right| {
136 (char_kind(left) != char_kind(right) && !right.is_whitespace()) || left == '\n'
137 })
138}
139
140pub fn previous_subword_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
141 find_preceding_boundary(map, point, |left, right| {
142 let is_word_start = char_kind(left) != char_kind(right) && !right.is_whitespace();
143 let is_subword_start =
144 left == '_' && right != '_' || left.is_lowercase() && right.is_uppercase();
145 is_word_start || is_subword_start || left == '\n'
146 })
147}
148
149pub fn next_word_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
150 find_boundary(map, point, |left, right| {
151 (char_kind(left) != char_kind(right) && !left.is_whitespace()) || right == '\n'
152 })
153}
154
155pub fn next_subword_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
156 find_boundary(map, point, |left, right| {
157 let is_word_end = (char_kind(left) != char_kind(right)) && !left.is_whitespace();
158 let is_subword_end =
159 left != '_' && right == '_' || left.is_lowercase() && right.is_uppercase();
160 is_word_end || is_subword_end || right == '\n'
161 })
162}
163
164/// Scans for a boundary from the start of each line preceding the given end point until a boundary
165/// is found, indicated by the given predicate returning true. The predicate is called with the
166/// character to the left and right of the candidate boundary location, and will be called with `\n`
167/// characters indicating the start or end of a line. If the predicate returns true multiple times
168/// on a line, the *rightmost* boundary is returned.
169pub fn find_preceding_boundary(
170 map: &DisplaySnapshot,
171 end: DisplayPoint,
172 mut is_boundary: impl FnMut(char, char) -> bool,
173) -> DisplayPoint {
174 let mut point = end;
175 loop {
176 *point.column_mut() = 0;
177 if point.row() > 0 {
178 if let Some(indent) = map.soft_wrap_indent(point.row() - 1) {
179 *point.column_mut() = indent;
180 }
181 }
182
183 let mut boundary = None;
184 let mut prev_ch = if point.is_zero() { None } else { Some('\n') };
185 for ch in map.chars_at(point) {
186 if point >= end {
187 break;
188 }
189
190 if let Some(prev_ch) = prev_ch {
191 if is_boundary(prev_ch, ch) {
192 boundary = Some(point);
193 }
194 }
195
196 if ch == '\n' {
197 break;
198 }
199
200 prev_ch = Some(ch);
201 *point.column_mut() += ch.len_utf8() as u32;
202 }
203
204 if let Some(boundary) = boundary {
205 return boundary;
206 } else if point.row() == 0 {
207 return DisplayPoint::zero();
208 } else {
209 *point.row_mut() -= 1;
210 }
211 }
212}
213
214/// Scans for a boundary following the given start point until a boundary is found, indicated by the
215/// given predicate returning true. The predicate is called with the character to the left and right
216/// of the candidate boundary location, and will be called with `\n` characters indicating the start
217/// or end of a line.
218pub fn find_boundary(
219 map: &DisplaySnapshot,
220 mut point: DisplayPoint,
221 mut is_boundary: impl FnMut(char, char) -> bool,
222) -> DisplayPoint {
223 let mut prev_ch = None;
224 for ch in map.chars_at(point) {
225 if let Some(prev_ch) = prev_ch {
226 if is_boundary(prev_ch, ch) {
227 break;
228 }
229 }
230
231 if ch == '\n' {
232 *point.row_mut() += 1;
233 *point.column_mut() = 0;
234 } else {
235 *point.column_mut() += ch.len_utf8() as u32;
236 }
237 prev_ch = Some(ch);
238 }
239 map.clip_point(point, Bias::Right)
240}
241
242pub fn is_inside_word(map: &DisplaySnapshot, point: DisplayPoint) -> bool {
243 let ix = map.clip_point(point, Bias::Left).to_offset(map, Bias::Left);
244 let text = &map.buffer_snapshot;
245 let next_char_kind = text.chars_at(ix).next().map(char_kind);
246 let prev_char_kind = text.reversed_chars_at(ix).next().map(char_kind);
247 prev_char_kind.zip(next_char_kind) == Some((CharKind::Word, CharKind::Word))
248}
249
250pub fn surrounding_word(map: &DisplaySnapshot, position: DisplayPoint) -> Range<DisplayPoint> {
251 let position = map
252 .clip_point(position, Bias::Left)
253 .to_offset(map, Bias::Left);
254 let (range, _) = map.buffer_snapshot.surrounding_word(position);
255 let start = range
256 .start
257 .to_point(&map.buffer_snapshot)
258 .to_display_point(map);
259 let end = range
260 .end
261 .to_point(&map.buffer_snapshot)
262 .to_display_point(map);
263 start..end
264}
265
266#[cfg(test)]
267mod tests {
268 use super::*;
269 use crate::{test::marked_display_snapshot, Buffer, DisplayMap, MultiBuffer};
270 use language::Point;
271
272 #[gpui::test]
273 fn test_previous_word_start(cx: &mut gpui::MutableAppContext) {
274 fn assert(marked_text: &str, cx: &mut gpui::MutableAppContext) {
275 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
276 assert_eq!(
277 previous_word_start(&snapshot, display_points[1]),
278 display_points[0]
279 );
280 }
281
282 assert("\n| |lorem", cx);
283 assert("|\n| lorem", cx);
284 assert(" |lorem|", cx);
285 assert("| |lorem", cx);
286 assert(" |lor|em", cx);
287 assert("\nlorem\n| |ipsum", cx);
288 assert("\n\n|\n|", cx);
289 assert(" |lorem |ipsum", cx);
290 assert("lorem|-|ipsum", cx);
291 assert("lorem|-#$@|ipsum", cx);
292 assert("|lorem_|ipsum", cx);
293 assert(" |defγ|", cx);
294 assert(" |bcΔ|", cx);
295 assert(" ab|——|cd", cx);
296 }
297
298 #[gpui::test]
299 fn test_previous_subword_start(cx: &mut gpui::MutableAppContext) {
300 fn assert(marked_text: &str, cx: &mut gpui::MutableAppContext) {
301 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
302 assert_eq!(
303 previous_subword_start(&snapshot, display_points[1]),
304 display_points[0]
305 );
306 }
307
308 // Subword boundaries are respected
309 assert("lorem_|ip|sum", cx);
310 assert("lorem_|ipsum|", cx);
311 assert("|lorem_|ipsum", cx);
312 assert("lorem_|ipsum_|dolor", cx);
313 assert("lorem|Ip|sum", cx);
314 assert("lorem|Ipsum|", cx);
315
316 // Word boundaries are still respected
317 assert("\n| |lorem", cx);
318 assert(" |lorem|", cx);
319 assert(" |lor|em", cx);
320 assert("\nlorem\n| |ipsum", cx);
321 assert("\n\n|\n|", cx);
322 assert(" |lorem |ipsum", cx);
323 assert("lorem|-|ipsum", cx);
324 assert("lorem|-#$@|ipsum", cx);
325 assert(" |defγ|", cx);
326 assert(" bc|Δ|", cx);
327 assert(" |bcδ|", cx);
328 assert(" ab|——|cd", cx);
329 }
330
331 #[gpui::test]
332 fn test_find_preceding_boundary(cx: &mut gpui::MutableAppContext) {
333 fn assert(
334 marked_text: &str,
335 cx: &mut gpui::MutableAppContext,
336 is_boundary: impl FnMut(char, char) -> bool,
337 ) {
338 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
339 assert_eq!(
340 find_preceding_boundary(&snapshot, display_points[1], is_boundary),
341 display_points[0]
342 );
343 }
344
345 assert("abc|def\ngh\nij|k", cx, |left, right| {
346 left == 'c' && right == 'd'
347 });
348 assert("abcdef\n|gh\nij|k", cx, |left, right| {
349 left == '\n' && right == 'g'
350 });
351 let mut line_count = 0;
352 assert("abcdef\n|gh\nij|k", cx, |left, _| {
353 if left == '\n' {
354 line_count += 1;
355 line_count == 2
356 } else {
357 false
358 }
359 });
360 }
361
362 #[gpui::test]
363 fn test_next_word_end(cx: &mut gpui::MutableAppContext) {
364 fn assert(marked_text: &str, cx: &mut gpui::MutableAppContext) {
365 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
366 assert_eq!(
367 next_word_end(&snapshot, display_points[0]),
368 display_points[1]
369 );
370 }
371
372 assert("\n| lorem|", cx);
373 assert(" |lorem|", cx);
374 assert(" lor|em|", cx);
375 assert(" lorem| |\nipsum\n", cx);
376 assert("\n|\n|\n\n", cx);
377 assert("lorem| ipsum| ", cx);
378 assert("lorem|-|ipsum", cx);
379 assert("lorem|#$@-|ipsum", cx);
380 assert("lorem|_ipsum|", cx);
381 assert(" |bcΔ|", cx);
382 assert(" ab|——|cd", cx);
383 }
384
385 #[gpui::test]
386 fn test_next_subword_end(cx: &mut gpui::MutableAppContext) {
387 fn assert(marked_text: &str, cx: &mut gpui::MutableAppContext) {
388 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
389 assert_eq!(
390 next_subword_end(&snapshot, display_points[0]),
391 display_points[1]
392 );
393 }
394
395 // Subword boundaries are respected
396 assert("lo|rem|_ipsum", cx);
397 assert("|lorem|_ipsum", cx);
398 assert("lorem|_ipsum|", cx);
399 assert("lorem|_ipsum|_dolor", cx);
400 assert("lo|rem|Ipsum", cx);
401 assert("lorem|Ipsum|Dolor", cx);
402
403 // Word boundaries are still respected
404 assert("\n| lorem|", cx);
405 assert(" |lorem|", cx);
406 assert(" lor|em|", cx);
407 assert(" lorem| |\nipsum\n", cx);
408 assert("\n|\n|\n\n", cx);
409 assert("lorem| ipsum| ", cx);
410 assert("lorem|-|ipsum", cx);
411 assert("lorem|#$@-|ipsum", cx);
412 assert("lorem|_ipsum|", cx);
413 assert(" |bc|Δ", cx);
414 assert(" ab|——|cd", cx);
415 }
416
417 #[gpui::test]
418 fn test_find_boundary(cx: &mut gpui::MutableAppContext) {
419 fn assert(
420 marked_text: &str,
421 cx: &mut gpui::MutableAppContext,
422 is_boundary: impl FnMut(char, char) -> bool,
423 ) {
424 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
425 assert_eq!(
426 find_boundary(&snapshot, display_points[0], is_boundary),
427 display_points[1]
428 );
429 }
430
431 assert("abc|def\ngh\nij|k", cx, |left, right| {
432 left == 'j' && right == 'k'
433 });
434 assert("ab|cdef\ngh\n|ijk", cx, |left, right| {
435 left == '\n' && right == 'i'
436 });
437 let mut line_count = 0;
438 assert("abc|def\ngh\n|ijk", cx, |left, _| {
439 if left == '\n' {
440 line_count += 1;
441 line_count == 2
442 } else {
443 false
444 }
445 });
446 }
447
448 #[gpui::test]
449 fn test_surrounding_word(cx: &mut gpui::MutableAppContext) {
450 fn assert(marked_text: &str, cx: &mut gpui::MutableAppContext) {
451 let (snapshot, display_points) = marked_display_snapshot(marked_text, cx);
452 assert_eq!(
453 surrounding_word(&snapshot, display_points[1]),
454 display_points[0]..display_points[2]
455 );
456 }
457
458 assert("||lorem| ipsum", cx);
459 assert("|lo|rem| ipsum", cx);
460 assert("|lorem|| ipsum", cx);
461 assert("lorem| | |ipsum", cx);
462 assert("lorem\n|||\nipsum", cx);
463 assert("lorem\n||ipsum|", cx);
464 assert("lorem,|| |ipsum", cx);
465 assert("|lorem||, ipsum", cx);
466 }
467
468 #[gpui::test]
469 fn test_move_up_and_down_with_excerpts(cx: &mut gpui::MutableAppContext) {
470 let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
471 let font_id = cx
472 .font_cache()
473 .select_font(family_id, &Default::default())
474 .unwrap();
475
476 let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndefg\nhijkl\nmn", cx));
477 let multibuffer = cx.add_model(|cx| {
478 let mut multibuffer = MultiBuffer::new(0);
479 multibuffer.push_excerpts(
480 buffer.clone(),
481 [
482 Point::new(0, 0)..Point::new(1, 4),
483 Point::new(2, 0)..Point::new(3, 2),
484 ],
485 cx,
486 );
487 multibuffer
488 });
489 let display_map =
490 cx.add_model(|cx| DisplayMap::new(multibuffer, 2, font_id, 14.0, None, 2, 2, cx));
491 let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
492
493 assert_eq!(snapshot.text(), "\n\nabc\ndefg\n\n\nhijkl\nmn");
494
495 // Can't move up into the first excerpt's header
496 assert_eq!(
497 up(&snapshot, DisplayPoint::new(2, 2), SelectionGoal::Column(2)),
498 (DisplayPoint::new(2, 0), SelectionGoal::Column(0)),
499 );
500 assert_eq!(
501 up(&snapshot, DisplayPoint::new(2, 0), SelectionGoal::None),
502 (DisplayPoint::new(2, 0), SelectionGoal::Column(0)),
503 );
504
505 // Move up and down within first excerpt
506 assert_eq!(
507 up(&snapshot, DisplayPoint::new(3, 4), SelectionGoal::Column(4)),
508 (DisplayPoint::new(2, 3), SelectionGoal::Column(4)),
509 );
510 assert_eq!(
511 down(&snapshot, DisplayPoint::new(2, 3), SelectionGoal::Column(4)),
512 (DisplayPoint::new(3, 4), SelectionGoal::Column(4)),
513 );
514
515 // Move up and down across second excerpt's header
516 assert_eq!(
517 up(&snapshot, DisplayPoint::new(6, 5), SelectionGoal::Column(5)),
518 (DisplayPoint::new(3, 4), SelectionGoal::Column(5)),
519 );
520 assert_eq!(
521 down(&snapshot, DisplayPoint::new(3, 4), SelectionGoal::Column(5)),
522 (DisplayPoint::new(6, 5), SelectionGoal::Column(5)),
523 );
524
525 // Can't move down off the end
526 assert_eq!(
527 down(&snapshot, DisplayPoint::new(7, 0), SelectionGoal::Column(0)),
528 (DisplayPoint::new(7, 2), SelectionGoal::Column(2)),
529 );
530 assert_eq!(
531 down(&snapshot, DisplayPoint::new(7, 2), SelectionGoal::Column(2)),
532 (DisplayPoint::new(7, 2), SelectionGoal::Column(2)),
533 );
534 }
535}