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(map: &DisplaySnapshot, point: DisplayPoint) -> Range<DisplayPoint> {
187    let mut start = map.clip_point(point, Bias::Left).to_offset(map, Bias::Left);
188    let mut end = start;
189
190    let text = &map.buffer_snapshot;
191    let mut next_chars = text.chars_at(start).peekable();
192    let mut prev_chars = text.reversed_chars_at(start).peekable();
193    let word_kind = cmp::max(
194        prev_chars.peek().copied().map(char_kind),
195        next_chars.peek().copied().map(char_kind),
196    );
197
198    for ch in prev_chars {
199        if Some(char_kind(ch)) == word_kind {
200            start -= ch.len_utf8();
201        } else {
202            break;
203        }
204    }
205
206    for ch in next_chars {
207        if Some(char_kind(ch)) == word_kind {
208            end += ch.len_utf8();
209        } else {
210            break;
211        }
212    }
213
214    start.to_point(&map.buffer_snapshot).to_display_point(map)
215        ..end.to_point(&map.buffer_snapshot).to_display_point(map)
216}
217
218#[cfg(test)]
219mod tests {
220    use super::*;
221    use crate::{
222        display_map::{BlockDisposition, BlockProperties},
223        Buffer, DisplayMap, ExcerptProperties, MultiBuffer,
224    };
225    use gpui::{elements::Empty, Element};
226    use language::Point;
227    use std::sync::Arc;
228
229    #[gpui::test]
230    fn test_move_up_and_down_with_excerpts(cx: &mut gpui::MutableAppContext) {
231        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
232        let font_id = cx
233            .font_cache()
234            .select_font(family_id, &Default::default())
235            .unwrap();
236
237        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndefg\nhijkl\nmn", cx));
238        let mut excerpt1_header_position = None;
239        let mut excerpt2_header_position = None;
240        let multibuffer = cx.add_model(|cx| {
241            let mut multibuffer = MultiBuffer::new(0);
242            let excerpt1_id = multibuffer.push_excerpt(
243                ExcerptProperties {
244                    buffer: &buffer,
245                    range: Point::new(0, 0)..Point::new(1, 4),
246                },
247                cx,
248            );
249            let excerpt2_id = multibuffer.push_excerpt(
250                ExcerptProperties {
251                    buffer: &buffer,
252                    range: Point::new(2, 0)..Point::new(3, 2),
253                },
254                cx,
255            );
256
257            excerpt1_header_position = Some(
258                multibuffer
259                    .read(cx)
260                    .anchor_in_excerpt(excerpt1_id, language::Anchor::min()),
261            );
262            excerpt2_header_position = Some(
263                multibuffer
264                    .read(cx)
265                    .anchor_in_excerpt(excerpt2_id, language::Anchor::min()),
266            );
267            multibuffer
268        });
269
270        let display_map =
271            cx.add_model(|cx| DisplayMap::new(multibuffer, 2, font_id, 14.0, None, cx));
272        display_map.update(cx, |display_map, cx| {
273            display_map.insert_blocks(
274                [
275                    BlockProperties {
276                        position: excerpt1_header_position.unwrap(),
277                        height: 2,
278                        render: Arc::new(|_| Empty::new().boxed()),
279                        disposition: BlockDisposition::Above,
280                    },
281                    BlockProperties {
282                        position: excerpt2_header_position.unwrap(),
283                        height: 3,
284                        render: Arc::new(|_| Empty::new().boxed()),
285                        disposition: BlockDisposition::Above,
286                    },
287                ],
288                cx,
289            )
290        });
291
292        let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
293        assert_eq!(snapshot.text(), "\n\nabc\ndefg\n\n\n\nhijkl\nmn");
294
295        // Can't move up into the first excerpt's header
296        assert_eq!(
297            up(&snapshot, DisplayPoint::new(2, 2), SelectionGoal::Column(2)).unwrap(),
298            (DisplayPoint::new(2, 0), SelectionGoal::Column(0)),
299        );
300        assert_eq!(
301            up(&snapshot, DisplayPoint::new(2, 0), SelectionGoal::None).unwrap(),
302            (DisplayPoint::new(2, 0), SelectionGoal::Column(0)),
303        );
304
305        // Move up and down within first excerpt
306        assert_eq!(
307            up(&snapshot, DisplayPoint::new(3, 4), SelectionGoal::Column(4)).unwrap(),
308            (DisplayPoint::new(2, 3), SelectionGoal::Column(4)),
309        );
310        assert_eq!(
311            down(&snapshot, DisplayPoint::new(2, 3), SelectionGoal::Column(4)).unwrap(),
312            (DisplayPoint::new(3, 4), SelectionGoal::Column(4)),
313        );
314
315        // Move up and down across second excerpt's header
316        assert_eq!(
317            up(&snapshot, DisplayPoint::new(7, 5), SelectionGoal::Column(5)).unwrap(),
318            (DisplayPoint::new(3, 4), SelectionGoal::Column(5)),
319        );
320        assert_eq!(
321            down(&snapshot, DisplayPoint::new(3, 4), SelectionGoal::Column(5)).unwrap(),
322            (DisplayPoint::new(7, 5), SelectionGoal::Column(5)),
323        );
324
325        // Can't move down off the end
326        assert_eq!(
327            down(&snapshot, DisplayPoint::new(8, 0), SelectionGoal::Column(0)).unwrap(),
328            (DisplayPoint::new(8, 2), SelectionGoal::Column(2)),
329        );
330        assert_eq!(
331            down(&snapshot, DisplayPoint::new(8, 2), SelectionGoal::Column(2)).unwrap(),
332            (DisplayPoint::new(8, 2), SelectionGoal::Column(2)),
333        );
334    }
335
336    #[gpui::test]
337    fn test_prev_next_word_boundary_multibyte(cx: &mut gpui::MutableAppContext) {
338        let tab_size = 4;
339        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
340        let font_id = cx
341            .font_cache()
342            .select_font(family_id, &Default::default())
343            .unwrap();
344        let font_size = 14.0;
345
346        let buffer = MultiBuffer::build_simple("a bcΔ defγ hi—jk", cx);
347        let display_map =
348            cx.add_model(|cx| DisplayMap::new(buffer, tab_size, font_id, font_size, None, cx));
349        let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
350        assert_eq!(
351            prev_word_boundary(&snapshot, DisplayPoint::new(0, 12)),
352            DisplayPoint::new(0, 7)
353        );
354        assert_eq!(
355            prev_word_boundary(&snapshot, DisplayPoint::new(0, 7)),
356            DisplayPoint::new(0, 2)
357        );
358        assert_eq!(
359            prev_word_boundary(&snapshot, DisplayPoint::new(0, 6)),
360            DisplayPoint::new(0, 2)
361        );
362        assert_eq!(
363            prev_word_boundary(&snapshot, DisplayPoint::new(0, 2)),
364            DisplayPoint::new(0, 0)
365        );
366        assert_eq!(
367            prev_word_boundary(&snapshot, DisplayPoint::new(0, 1)),
368            DisplayPoint::new(0, 0)
369        );
370
371        assert_eq!(
372            next_word_boundary(&snapshot, DisplayPoint::new(0, 0)),
373            DisplayPoint::new(0, 1)
374        );
375        assert_eq!(
376            next_word_boundary(&snapshot, DisplayPoint::new(0, 1)),
377            DisplayPoint::new(0, 6)
378        );
379        assert_eq!(
380            next_word_boundary(&snapshot, DisplayPoint::new(0, 2)),
381            DisplayPoint::new(0, 6)
382        );
383        assert_eq!(
384            next_word_boundary(&snapshot, DisplayPoint::new(0, 6)),
385            DisplayPoint::new(0, 12)
386        );
387        assert_eq!(
388            next_word_boundary(&snapshot, DisplayPoint::new(0, 7)),
389            DisplayPoint::new(0, 12)
390        );
391    }
392
393    #[gpui::test]
394    fn test_surrounding_word(cx: &mut gpui::MutableAppContext) {
395        let tab_size = 4;
396        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
397        let font_id = cx
398            .font_cache()
399            .select_font(family_id, &Default::default())
400            .unwrap();
401        let font_size = 14.0;
402        let buffer = MultiBuffer::build_simple("lorem ipsum   dolor\n    sit", cx);
403        let display_map =
404            cx.add_model(|cx| DisplayMap::new(buffer, tab_size, font_id, font_size, None, cx));
405        let snapshot = display_map.update(cx, |map, cx| map.snapshot(cx));
406
407        assert_eq!(
408            surrounding_word(&snapshot, DisplayPoint::new(0, 0)),
409            DisplayPoint::new(0, 0)..DisplayPoint::new(0, 5)
410        );
411        assert_eq!(
412            surrounding_word(&snapshot, DisplayPoint::new(0, 2)),
413            DisplayPoint::new(0, 0)..DisplayPoint::new(0, 5)
414        );
415        assert_eq!(
416            surrounding_word(&snapshot, DisplayPoint::new(0, 5)),
417            DisplayPoint::new(0, 0)..DisplayPoint::new(0, 5)
418        );
419        assert_eq!(
420            surrounding_word(&snapshot, DisplayPoint::new(0, 6)),
421            DisplayPoint::new(0, 6)..DisplayPoint::new(0, 11)
422        );
423        assert_eq!(
424            surrounding_word(&snapshot, DisplayPoint::new(0, 7)),
425            DisplayPoint::new(0, 6)..DisplayPoint::new(0, 11)
426        );
427        assert_eq!(
428            surrounding_word(&snapshot, DisplayPoint::new(0, 11)),
429            DisplayPoint::new(0, 6)..DisplayPoint::new(0, 11)
430        );
431        assert_eq!(
432            surrounding_word(&snapshot, DisplayPoint::new(0, 13)),
433            DisplayPoint::new(0, 11)..DisplayPoint::new(0, 14)
434        );
435        assert_eq!(
436            surrounding_word(&snapshot, DisplayPoint::new(0, 14)),
437            DisplayPoint::new(0, 14)..DisplayPoint::new(0, 19)
438        );
439        assert_eq!(
440            surrounding_word(&snapshot, DisplayPoint::new(0, 17)),
441            DisplayPoint::new(0, 14)..DisplayPoint::new(0, 19)
442        );
443        assert_eq!(
444            surrounding_word(&snapshot, DisplayPoint::new(0, 19)),
445            DisplayPoint::new(0, 14)..DisplayPoint::new(0, 19)
446        );
447        assert_eq!(
448            surrounding_word(&snapshot, DisplayPoint::new(1, 0)),
449            DisplayPoint::new(1, 0)..DisplayPoint::new(1, 4)
450        );
451        assert_eq!(
452            surrounding_word(&snapshot, DisplayPoint::new(1, 1)),
453            DisplayPoint::new(1, 0)..DisplayPoint::new(1, 4)
454        );
455        assert_eq!(
456            surrounding_word(&snapshot, DisplayPoint::new(1, 6)),
457            DisplayPoint::new(1, 4)..DisplayPoint::new(1, 7)
458        );
459        assert_eq!(
460            surrounding_word(&snapshot, DisplayPoint::new(1, 7)),
461            DisplayPoint::new(1, 4)..DisplayPoint::new(1, 7)
462        );
463    }
464}