movement.rs

  1use super::{Bias, DisplayPoint, DisplaySnapshot, SelectionGoal, ToDisplayPoint};
  2use crate::{char_kind, CharKind, ToPoint};
  3use anyhow::Result;
  4use std::{cmp, ops::Range};
  5
  6pub fn left(map: &DisplaySnapshot, mut point: DisplayPoint) -> Result<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    Ok(map.clip_point(point, Bias::Left))
 14}
 15
 16pub fn right(map: &DisplaySnapshot, mut point: DisplayPoint) -> Result<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    Ok(map.clip_point(point, Bias::Right))
 25}
 26
 27pub fn up(
 28    map: &DisplaySnapshot,
 29    start: DisplayPoint,
 30    goal: SelectionGoal,
 31) -> Result<(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    Ok((
 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) -> Result<(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    Ok((
 89        map.clip_point(point, clip_bias),
 90        SelectionGoal::Column(goal_column),
 91    ))
 92}
 93
 94pub fn line_beginning(
 95    map: &DisplaySnapshot,
 96    point: DisplayPoint,
 97    toggle_indent: bool,
 98) -> DisplayPoint {
 99    let (indent, is_blank) = map.line_indent(point.row());
100    if toggle_indent && !is_blank && point.column() != indent {
101        DisplayPoint::new(point.row(), indent)
102    } else {
103        DisplayPoint::new(point.row(), 0)
104    }
105}
106
107pub fn line_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
108    let line_end = DisplayPoint::new(point.row(), map.line_len(point.row()));
109    map.clip_point(line_end, Bias::Left)
110}
111
112pub fn prev_word_boundary(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
113    let mut line_start = 0;
114    if point.row() > 0 {
115        if let Some(indent) = map.soft_wrap_indent(point.row() - 1) {
116            line_start = indent;
117        }
118    }
119
120    if point.column() == line_start {
121        if point.row() == 0 {
122            return DisplayPoint::new(0, 0);
123        } else {
124            let row = point.row() - 1;
125            point = map.clip_point(DisplayPoint::new(row, map.line_len(row)), Bias::Left);
126        }
127    }
128
129    let mut boundary = DisplayPoint::new(point.row(), 0);
130    let mut column = 0;
131    let mut prev_char_kind = CharKind::Newline;
132    for c in map.chars_at(DisplayPoint::new(point.row(), 0)) {
133        if column >= point.column() {
134            break;
135        }
136
137        let char_kind = char_kind(c);
138        if char_kind != prev_char_kind
139            && char_kind != CharKind::Whitespace
140            && char_kind != CharKind::Newline
141        {
142            *boundary.column_mut() = column;
143        }
144
145        prev_char_kind = char_kind;
146        column += c.len_utf8() as u32;
147    }
148    boundary
149}
150
151pub fn next_word_boundary(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
152    let mut prev_char_kind = None;
153    for c in map.chars_at(point) {
154        let char_kind = char_kind(c);
155        if let Some(prev_char_kind) = prev_char_kind {
156            if c == '\n' {
157                break;
158            }
159            if prev_char_kind != char_kind
160                && prev_char_kind != CharKind::Whitespace
161                && prev_char_kind != CharKind::Newline
162            {
163                break;
164            }
165        }
166
167        if c == '\n' {
168            *point.row_mut() += 1;
169            *point.column_mut() = 0;
170        } else {
171            *point.column_mut() += c.len_utf8() as u32;
172        }
173        prev_char_kind = Some(char_kind);
174    }
175    map.clip_point(point, Bias::Right)
176}
177
178pub fn is_inside_word(map: &DisplaySnapshot, point: DisplayPoint) -> bool {
179    let ix = map.clip_point(point, Bias::Left).to_offset(map, Bias::Left);
180    let text = &map.buffer_snapshot;
181    let next_char_kind = text.chars_at(ix).next().map(char_kind);
182    let prev_char_kind = text.reversed_chars_at(ix).next().map(char_kind);
183    prev_char_kind.zip(next_char_kind) == Some((CharKind::Word, CharKind::Word))
184}
185
186pub fn surrounding_word(
187    map: &DisplaySnapshot,
188    point: DisplayPoint,
189) -> (Range<DisplayPoint>, Option<CharKind>) {
190    let mut start = map.clip_point(point, Bias::Left).to_offset(map, Bias::Left);
191    let mut end = start;
192
193    let text = &map.buffer_snapshot;
194    let mut next_chars = text.chars_at(start).peekable();
195    let mut prev_chars = text.reversed_chars_at(start).peekable();
196    let word_kind = cmp::max(
197        prev_chars.peek().copied().map(char_kind),
198        next_chars.peek().copied().map(char_kind),
199    );
200
201    for ch in prev_chars {
202        if Some(char_kind(ch)) == word_kind {
203            start -= ch.len_utf8();
204        } else {
205            break;
206        }
207    }
208
209    for ch in next_chars {
210        if Some(char_kind(ch)) == word_kind {
211            end += ch.len_utf8();
212        } else {
213            break;
214        }
215    }
216
217    (
218        start.to_point(&map.buffer_snapshot).to_display_point(map)
219            ..end.to_point(&map.buffer_snapshot).to_display_point(map),
220        word_kind,
221    )
222}
223
224#[cfg(test)]
225mod tests {
226    use super::*;
227    use crate::{
228        display_map::{BlockDisposition, BlockProperties},
229        Buffer, DisplayMap, ExcerptProperties, MultiBuffer,
230    };
231    use gpui::{elements::Empty, Element};
232    use language::Point;
233    use std::sync::Arc;
234
235    #[gpui::test]
236    fn test_move_up_and_down_with_excerpts(cx: &mut gpui::MutableAppContext) {
237        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
238        let font_id = cx
239            .font_cache()
240            .select_font(family_id, &Default::default())
241            .unwrap();
242
243        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndefg\nhijkl\nmn", cx));
244        let mut excerpt1_header_position = None;
245        let mut excerpt2_header_position = None;
246        let multibuffer = cx.add_model(|cx| {
247            let mut multibuffer = MultiBuffer::new(0);
248            let excerpt1_id = multibuffer.push_excerpt(
249                ExcerptProperties {
250                    buffer: &buffer,
251                    range: Point::new(0, 0)..Point::new(1, 4),
252                },
253                cx,
254            );
255            let excerpt2_id = multibuffer.push_excerpt(
256                ExcerptProperties {
257                    buffer: &buffer,
258                    range: Point::new(2, 0)..Point::new(3, 2),
259                },
260                cx,
261            );
262
263            excerpt1_header_position = Some(
264                multibuffer
265                    .read(cx)
266                    .anchor_in_excerpt(excerpt1_id, language::Anchor::min()),
267            );
268            excerpt2_header_position = Some(
269                multibuffer
270                    .read(cx)
271                    .anchor_in_excerpt(excerpt2_id, language::Anchor::min()),
272            );
273            multibuffer
274        });
275
276        let display_map =
277            cx.add_model(|cx| DisplayMap::new(multibuffer, 2, font_id, 14.0, None, cx));
278        display_map.update(cx, |display_map, cx| {
279            display_map.insert_blocks(
280                [
281                    BlockProperties {
282                        position: excerpt1_header_position.unwrap(),
283                        height: 2,
284                        render: Arc::new(|_| Empty::new().boxed()),
285                        disposition: BlockDisposition::Above,
286                    },
287                    BlockProperties {
288                        position: excerpt2_header_position.unwrap(),
289                        height: 3,
290                        render: Arc::new(|_| Empty::new().boxed()),
291                        disposition: BlockDisposition::Above,
292                    },
293                ],
294                cx,
295            )
296        });
297
298        let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
299        assert_eq!(snapshot.text(), "\n\nabc\ndefg\n\n\n\nhijkl\nmn");
300
301        // Can't move up into the first excerpt's header
302        assert_eq!(
303            up(&snapshot, DisplayPoint::new(2, 2), SelectionGoal::Column(2)).unwrap(),
304            (DisplayPoint::new(2, 0), SelectionGoal::Column(0)),
305        );
306        assert_eq!(
307            up(&snapshot, DisplayPoint::new(2, 0), SelectionGoal::None).unwrap(),
308            (DisplayPoint::new(2, 0), SelectionGoal::Column(0)),
309        );
310
311        // Move up and down within first excerpt
312        assert_eq!(
313            up(&snapshot, DisplayPoint::new(3, 4), SelectionGoal::Column(4)).unwrap(),
314            (DisplayPoint::new(2, 3), SelectionGoal::Column(4)),
315        );
316        assert_eq!(
317            down(&snapshot, DisplayPoint::new(2, 3), SelectionGoal::Column(4)).unwrap(),
318            (DisplayPoint::new(3, 4), SelectionGoal::Column(4)),
319        );
320
321        // Move up and down across second excerpt's header
322        assert_eq!(
323            up(&snapshot, DisplayPoint::new(7, 5), SelectionGoal::Column(5)).unwrap(),
324            (DisplayPoint::new(3, 4), SelectionGoal::Column(5)),
325        );
326        assert_eq!(
327            down(&snapshot, DisplayPoint::new(3, 4), SelectionGoal::Column(5)).unwrap(),
328            (DisplayPoint::new(7, 5), SelectionGoal::Column(5)),
329        );
330
331        // Can't move down off the end
332        assert_eq!(
333            down(&snapshot, DisplayPoint::new(8, 0), SelectionGoal::Column(0)).unwrap(),
334            (DisplayPoint::new(8, 2), SelectionGoal::Column(2)),
335        );
336        assert_eq!(
337            down(&snapshot, DisplayPoint::new(8, 2), SelectionGoal::Column(2)).unwrap(),
338            (DisplayPoint::new(8, 2), SelectionGoal::Column(2)),
339        );
340    }
341
342    #[gpui::test]
343    fn test_prev_next_word_boundary_multibyte(cx: &mut gpui::MutableAppContext) {
344        let tab_size = 4;
345        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
346        let font_id = cx
347            .font_cache()
348            .select_font(family_id, &Default::default())
349            .unwrap();
350        let font_size = 14.0;
351
352        let buffer = MultiBuffer::build_simple("a bcΔ defγ hi—jk", cx);
353        let display_map =
354            cx.add_model(|cx| DisplayMap::new(buffer, tab_size, font_id, font_size, None, cx));
355        let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
356        assert_eq!(
357            prev_word_boundary(&snapshot, DisplayPoint::new(0, 12)),
358            DisplayPoint::new(0, 7)
359        );
360        assert_eq!(
361            prev_word_boundary(&snapshot, DisplayPoint::new(0, 7)),
362            DisplayPoint::new(0, 2)
363        );
364        assert_eq!(
365            prev_word_boundary(&snapshot, DisplayPoint::new(0, 6)),
366            DisplayPoint::new(0, 2)
367        );
368        assert_eq!(
369            prev_word_boundary(&snapshot, DisplayPoint::new(0, 2)),
370            DisplayPoint::new(0, 0)
371        );
372        assert_eq!(
373            prev_word_boundary(&snapshot, DisplayPoint::new(0, 1)),
374            DisplayPoint::new(0, 0)
375        );
376
377        assert_eq!(
378            next_word_boundary(&snapshot, DisplayPoint::new(0, 0)),
379            DisplayPoint::new(0, 1)
380        );
381        assert_eq!(
382            next_word_boundary(&snapshot, DisplayPoint::new(0, 1)),
383            DisplayPoint::new(0, 6)
384        );
385        assert_eq!(
386            next_word_boundary(&snapshot, DisplayPoint::new(0, 2)),
387            DisplayPoint::new(0, 6)
388        );
389        assert_eq!(
390            next_word_boundary(&snapshot, DisplayPoint::new(0, 6)),
391            DisplayPoint::new(0, 12)
392        );
393        assert_eq!(
394            next_word_boundary(&snapshot, DisplayPoint::new(0, 7)),
395            DisplayPoint::new(0, 12)
396        );
397    }
398
399    #[gpui::test]
400    fn test_surrounding_word(cx: &mut gpui::MutableAppContext) {
401        let tab_size = 4;
402        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
403        let font_id = cx
404            .font_cache()
405            .select_font(family_id, &Default::default())
406            .unwrap();
407        let font_size = 14.0;
408        let buffer = MultiBuffer::build_simple("lorem ipsum   dolor\n    sit", cx);
409        let display_map =
410            cx.add_model(|cx| DisplayMap::new(buffer, tab_size, font_id, font_size, None, cx));
411        let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
412
413        assert_eq!(
414            surrounding_word(&snapshot, DisplayPoint::new(0, 0)),
415            (
416                DisplayPoint::new(0, 0)..DisplayPoint::new(0, 5),
417                Some(CharKind::Word)
418            )
419        );
420        assert_eq!(
421            surrounding_word(&snapshot, DisplayPoint::new(0, 2)),
422            (
423                DisplayPoint::new(0, 0)..DisplayPoint::new(0, 5),
424                Some(CharKind::Word)
425            )
426        );
427        assert_eq!(
428            surrounding_word(&snapshot, DisplayPoint::new(0, 5)),
429            (
430                DisplayPoint::new(0, 0)..DisplayPoint::new(0, 5),
431                Some(CharKind::Word)
432            )
433        );
434        assert_eq!(
435            surrounding_word(&snapshot, DisplayPoint::new(0, 6)),
436            (
437                DisplayPoint::new(0, 6)..DisplayPoint::new(0, 11),
438                Some(CharKind::Word)
439            )
440        );
441        assert_eq!(
442            surrounding_word(&snapshot, DisplayPoint::new(0, 7)),
443            (
444                DisplayPoint::new(0, 6)..DisplayPoint::new(0, 11),
445                Some(CharKind::Word)
446            )
447        );
448        assert_eq!(
449            surrounding_word(&snapshot, DisplayPoint::new(0, 11)),
450            (
451                DisplayPoint::new(0, 6)..DisplayPoint::new(0, 11),
452                Some(CharKind::Word)
453            )
454        );
455        assert_eq!(
456            surrounding_word(&snapshot, DisplayPoint::new(0, 13)),
457            (
458                DisplayPoint::new(0, 11)..DisplayPoint::new(0, 14),
459                Some(CharKind::Whitespace)
460            )
461        );
462        assert_eq!(
463            surrounding_word(&snapshot, DisplayPoint::new(0, 14)),
464            (
465                DisplayPoint::new(0, 14)..DisplayPoint::new(0, 19),
466                Some(CharKind::Word)
467            )
468        );
469        assert_eq!(
470            surrounding_word(&snapshot, DisplayPoint::new(0, 17)),
471            (
472                DisplayPoint::new(0, 14)..DisplayPoint::new(0, 19),
473                Some(CharKind::Word)
474            )
475        );
476        assert_eq!(
477            surrounding_word(&snapshot, DisplayPoint::new(0, 19)),
478            (
479                DisplayPoint::new(0, 14)..DisplayPoint::new(0, 19),
480                Some(CharKind::Word)
481            )
482        );
483        assert_eq!(
484            surrounding_word(&snapshot, DisplayPoint::new(1, 0)),
485            (
486                DisplayPoint::new(1, 0)..DisplayPoint::new(1, 4),
487                Some(CharKind::Whitespace)
488            )
489        );
490        assert_eq!(
491            surrounding_word(&snapshot, DisplayPoint::new(1, 1)),
492            (
493                DisplayPoint::new(1, 0)..DisplayPoint::new(1, 4),
494                Some(CharKind::Whitespace)
495            )
496        );
497        assert_eq!(
498            surrounding_word(&snapshot, DisplayPoint::new(1, 6)),
499            (
500                DisplayPoint::new(1, 4)..DisplayPoint::new(1, 7),
501                Some(CharKind::Word)
502            )
503        );
504        assert_eq!(
505            surrounding_word(&snapshot, DisplayPoint::new(1, 7)),
506            (
507                DisplayPoint::new(1, 4)..DisplayPoint::new(1, 7),
508                Some(CharKind::Word)
509            )
510        );
511    }
512}