motion.rs

  1use editor::{
  2    char_kind,
  3    display_map::{DisplaySnapshot, ToDisplayPoint},
  4    movement, Bias, CharKind, DisplayPoint,
  5};
  6use gpui::{actions, impl_actions, MutableAppContext};
  7use language::{Selection, SelectionGoal};
  8use serde::Deserialize;
  9use workspace::Workspace;
 10
 11use crate::{
 12    normal::normal_motion,
 13    state::{Mode, Operator},
 14    visual::visual_motion,
 15    Vim,
 16};
 17
 18#[derive(Copy, Clone, Debug)]
 19pub enum Motion {
 20    Left,
 21    Down,
 22    Up,
 23    Right,
 24    NextWordStart { ignore_punctuation: bool },
 25    NextWordEnd { ignore_punctuation: bool },
 26    PreviousWordStart { ignore_punctuation: bool },
 27    FirstNonWhitespace,
 28    CurrentLine,
 29    StartOfLine,
 30    EndOfLine,
 31    StartOfDocument,
 32    EndOfDocument,
 33}
 34
 35#[derive(Clone, Deserialize)]
 36#[serde(rename_all = "camelCase")]
 37struct NextWordStart {
 38    #[serde(default)]
 39    ignore_punctuation: bool,
 40}
 41
 42#[derive(Clone, Deserialize)]
 43#[serde(rename_all = "camelCase")]
 44struct NextWordEnd {
 45    #[serde(default)]
 46    ignore_punctuation: bool,
 47}
 48
 49#[derive(Clone, Deserialize)]
 50#[serde(rename_all = "camelCase")]
 51struct PreviousWordStart {
 52    #[serde(default)]
 53    ignore_punctuation: bool,
 54}
 55
 56actions!(
 57    vim,
 58    [
 59        Left,
 60        Down,
 61        Up,
 62        Right,
 63        FirstNonWhitespace,
 64        StartOfLine,
 65        EndOfLine,
 66        CurrentLine,
 67        StartOfDocument,
 68        EndOfDocument
 69    ]
 70);
 71impl_actions!(vim, [NextWordStart, NextWordEnd, PreviousWordStart]);
 72
 73pub fn init(cx: &mut MutableAppContext) {
 74    cx.add_action(|_: &mut Workspace, _: &Left, cx: _| motion(Motion::Left, cx));
 75    cx.add_action(|_: &mut Workspace, _: &Down, cx: _| motion(Motion::Down, cx));
 76    cx.add_action(|_: &mut Workspace, _: &Up, cx: _| motion(Motion::Up, cx));
 77    cx.add_action(|_: &mut Workspace, _: &Right, cx: _| motion(Motion::Right, cx));
 78    cx.add_action(|_: &mut Workspace, _: &FirstNonWhitespace, cx: _| {
 79        motion(Motion::FirstNonWhitespace, cx)
 80    });
 81    cx.add_action(|_: &mut Workspace, _: &StartOfLine, cx: _| motion(Motion::StartOfLine, cx));
 82    cx.add_action(|_: &mut Workspace, _: &EndOfLine, cx: _| motion(Motion::EndOfLine, cx));
 83    cx.add_action(|_: &mut Workspace, _: &CurrentLine, cx: _| motion(Motion::CurrentLine, cx));
 84    cx.add_action(|_: &mut Workspace, _: &StartOfDocument, cx: _| {
 85        motion(Motion::StartOfDocument, cx)
 86    });
 87    cx.add_action(|_: &mut Workspace, _: &EndOfDocument, cx: _| motion(Motion::EndOfDocument, cx));
 88
 89    cx.add_action(
 90        |_: &mut Workspace, &NextWordStart { ignore_punctuation }: &NextWordStart, cx: _| {
 91            motion(Motion::NextWordStart { ignore_punctuation }, cx)
 92        },
 93    );
 94    cx.add_action(
 95        |_: &mut Workspace, &NextWordEnd { ignore_punctuation }: &NextWordEnd, cx: _| {
 96            motion(Motion::NextWordEnd { ignore_punctuation }, cx)
 97        },
 98    );
 99    cx.add_action(
100        |_: &mut Workspace,
101         &PreviousWordStart { ignore_punctuation }: &PreviousWordStart,
102         cx: _| { motion(Motion::PreviousWordStart { ignore_punctuation }, cx) },
103    );
104}
105
106fn motion(motion: Motion, cx: &mut MutableAppContext) {
107    Vim::update(cx, |vim, cx| {
108        if let Some(Operator::Namespace(_)) = vim.active_operator() {
109            vim.pop_operator(cx);
110        }
111    });
112    match Vim::read(cx).state.mode {
113        Mode::Normal => normal_motion(motion, cx),
114        Mode::Visual => visual_motion(motion, cx),
115        Mode::Insert => {
116            // Shouldn't execute a motion in insert mode. Ignoring
117        }
118    }
119}
120
121// Motion handling is specified here:
122// https://github.com/vim/vim/blob/master/runtime/doc/motion.txt
123impl Motion {
124    pub fn linewise(self) -> bool {
125        use Motion::*;
126        match self {
127            Down | Up | StartOfDocument | EndOfDocument | CurrentLine => true,
128            _ => false,
129        }
130    }
131
132    pub fn inclusive(self) -> bool {
133        use Motion::*;
134        if self.linewise() {
135            return true;
136        }
137
138        match self {
139            EndOfLine | NextWordEnd { .. } => true,
140            Left | Right | StartOfLine | NextWordStart { .. } | PreviousWordStart { .. } => false,
141            _ => panic!("Exclusivity not defined for {self:?}"),
142        }
143    }
144
145    pub fn move_point(
146        self,
147        map: &DisplaySnapshot,
148        point: DisplayPoint,
149        goal: SelectionGoal,
150    ) -> (DisplayPoint, SelectionGoal) {
151        use Motion::*;
152        match self {
153            Left => (left(map, point), SelectionGoal::None),
154            Down => movement::down(map, point, goal, true),
155            Up => movement::up(map, point, goal, true),
156            Right => (right(map, point), SelectionGoal::None),
157            NextWordStart { ignore_punctuation } => (
158                next_word_start(map, point, ignore_punctuation),
159                SelectionGoal::None,
160            ),
161            NextWordEnd { ignore_punctuation } => (
162                next_word_end(map, point, ignore_punctuation),
163                SelectionGoal::None,
164            ),
165            PreviousWordStart { ignore_punctuation } => (
166                previous_word_start(map, point, ignore_punctuation),
167                SelectionGoal::None,
168            ),
169            FirstNonWhitespace => (first_non_whitespace(map, point), SelectionGoal::None),
170            StartOfLine => (start_of_line(map, point), SelectionGoal::None),
171            EndOfLine => (end_of_line(map, point), SelectionGoal::None),
172            CurrentLine => (end_of_line(map, point), SelectionGoal::None),
173            StartOfDocument => (start_of_document(map, point), SelectionGoal::None),
174            EndOfDocument => (end_of_document(map, point), SelectionGoal::None),
175        }
176    }
177
178    // Expands a selection using self motion for an operator
179    pub fn expand_selection(
180        self,
181        map: &DisplaySnapshot,
182        selection: &mut Selection<DisplayPoint>,
183        expand_to_surrounding_newline: bool,
184    ) {
185        let (head, goal) = self.move_point(map, selection.head(), selection.goal);
186        selection.set_head(head, goal);
187
188        if self.linewise() {
189            selection.start = map.prev_line_boundary(selection.start.to_point(map)).1;
190
191            if expand_to_surrounding_newline {
192                if selection.end.row() < map.max_point().row() {
193                    *selection.end.row_mut() += 1;
194                    *selection.end.column_mut() = 0;
195                    // Don't reset the end here
196                    return;
197                } else if selection.start.row() > 0 {
198                    *selection.start.row_mut() -= 1;
199                    *selection.start.column_mut() = map.line_len(selection.start.row());
200                }
201            }
202
203            selection.end = map.next_line_boundary(selection.end.to_point(map)).1;
204        } else {
205            // If the motion is exclusive and the end of the motion is in column 1, the
206            // end of the motion is moved to the end of the previous line and the motion
207            // becomes inclusive. Example: "}" moves to the first line after a paragraph,
208            // but "d}" will not include that line.
209            let mut inclusive = self.inclusive();
210            if !inclusive
211                && selection.end.row() > selection.start.row()
212                && selection.end.column() == 0
213                && selection.end.row() > 0
214            {
215                inclusive = true;
216                *selection.end.row_mut() -= 1;
217                *selection.end.column_mut() = 0;
218                selection.end = map.clip_point(
219                    map.next_line_boundary(selection.end.to_point(map)).1,
220                    Bias::Left,
221                );
222            }
223
224            if inclusive && selection.end.column() < map.line_len(selection.end.row()) {
225                *selection.end.column_mut() += 1;
226            }
227        }
228    }
229}
230
231fn left(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
232    *point.column_mut() = point.column().saturating_sub(1);
233    map.clip_point(point, Bias::Left)
234}
235
236fn right(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
237    *point.column_mut() += 1;
238    map.clip_point(point, Bias::Right)
239}
240
241fn next_word_start(
242    map: &DisplaySnapshot,
243    point: DisplayPoint,
244    ignore_punctuation: bool,
245) -> DisplayPoint {
246    let mut crossed_newline = false;
247    movement::find_boundary(map, point, |left, right| {
248        let left_kind = char_kind(left).coerce_punctuation(ignore_punctuation);
249        let right_kind = char_kind(right).coerce_punctuation(ignore_punctuation);
250        let at_newline = right == '\n';
251
252        let found = (left_kind != right_kind && !right.is_whitespace())
253            || at_newline && crossed_newline
254            || at_newline && left == '\n'; // Prevents skipping repeated empty lines
255
256        if at_newline {
257            crossed_newline = true;
258        }
259        found
260    })
261}
262
263fn next_word_end(
264    map: &DisplaySnapshot,
265    mut point: DisplayPoint,
266    ignore_punctuation: bool,
267) -> DisplayPoint {
268    *point.column_mut() += 1;
269    point = movement::find_boundary(map, point, |left, right| {
270        let left_kind = char_kind(left).coerce_punctuation(ignore_punctuation);
271        let right_kind = char_kind(right).coerce_punctuation(ignore_punctuation);
272
273        left_kind != right_kind && !left.is_whitespace()
274    });
275    // find_boundary clips, so if the character after the next character is a newline or at the end of the document, we know
276    // we have backtraced already
277    if !map
278        .chars_at(point)
279        .skip(1)
280        .next()
281        .map(|c| c == '\n')
282        .unwrap_or(true)
283    {
284        *point.column_mut() = point.column().saturating_sub(1);
285    }
286    map.clip_point(point, Bias::Left)
287}
288
289fn previous_word_start(
290    map: &DisplaySnapshot,
291    mut point: DisplayPoint,
292    ignore_punctuation: bool,
293) -> DisplayPoint {
294    // This works even though find_preceding_boundary is called for every character in the line containing
295    // cursor because the newline is checked only once.
296    point = movement::find_preceding_boundary(map, point, |left, right| {
297        let left_kind = char_kind(left).coerce_punctuation(ignore_punctuation);
298        let right_kind = char_kind(right).coerce_punctuation(ignore_punctuation);
299
300        (left_kind != right_kind && !right.is_whitespace()) || left == '\n'
301    });
302    point
303}
304
305fn first_non_whitespace(map: &DisplaySnapshot, mut point: DisplayPoint) -> DisplayPoint {
306    let mut column = 0;
307    for ch in map.chars_at(DisplayPoint::new(point.row(), 0)) {
308        if ch == '\n' {
309            return point;
310        }
311
312        if char_kind(ch) != CharKind::Whitespace {
313            break;
314        }
315
316        column += ch.len_utf8() as u32;
317    }
318
319    *point.column_mut() = column;
320    map.clip_point(point, Bias::Left)
321}
322
323fn start_of_line(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
324    map.prev_line_boundary(point.to_point(map)).1
325}
326
327fn end_of_line(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
328    map.clip_point(map.next_line_boundary(point.to_point(map)).1, Bias::Left)
329}
330
331fn start_of_document(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
332    let mut new_point = 0usize.to_display_point(map);
333    *new_point.column_mut() = point.column();
334    map.clip_point(new_point, Bias::Left)
335}
336
337fn end_of_document(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
338    let mut new_point = map.max_point();
339    *new_point.column_mut() = point.column();
340    map.clip_point(new_point, Bias::Left)
341}