diff options
Diffstat (limited to 'helix-core/src/movement.rs')
| -rw-r--r-- | helix-core/src/movement.rs | 181 |
1 files changed, 123 insertions, 58 deletions
diff --git a/helix-core/src/movement.rs b/helix-core/src/movement.rs index f9e5deb4..bc56f9a4 100644 --- a/helix-core/src/movement.rs +++ b/helix-core/src/movement.rs @@ -5,8 +5,11 @@ use ropey::iter::Chars; use crate::{ chars::{categorize_char, char_is_line_ending, CharCategory}, coords_at_pos, - graphemes::{nth_next_grapheme_boundary, nth_prev_grapheme_boundary}, - line_ending::{get_line_ending, line_end_char_index}, + graphemes::{ + next_grapheme_boundary, nth_next_grapheme_boundary, nth_prev_grapheme_boundary, + prev_grapheme_boundary, RopeGraphemes, + }, + line_ending::line_without_line_ending, pos_at_coords, Position, Range, RopeSlice, }; @@ -29,25 +32,60 @@ pub fn move_horizontally( count: usize, behaviour: Movement, ) -> Range { - let pos = range.head; - let line = slice.char_to_line(pos); - // TODO: we can optimize clamping by passing in RopeSlice limited to current line. that way - // we stop calculating past start/end of line. - let pos = match dir { - Direction::Backward => { - let start = slice.line_to_char(line); - nth_prev_grapheme_boundary(slice, pos, count).max(start) + match (behaviour, dir) { + (Movement::Move, Direction::Backward) => { + let count = if range.anchor < range.head { + count + 1 + } else { + count + }; + let pos = nth_prev_grapheme_boundary(slice, range.head, count); + Range::new(pos, pos) } - Direction::Forward => { - let end_char_idx = line_end_char_index(&slice, line); - nth_next_grapheme_boundary(slice, pos, count).min(end_char_idx) + (Movement::Move, Direction::Forward) => { + let count = if range.anchor < range.head { + count - 1 + } else { + count + }; + let pos = nth_next_grapheme_boundary(slice, range.head, count); + Range::new(pos, pos) } - }; - let anchor = match behaviour { - Movement::Extend => range.anchor, - Movement::Move => pos, - }; - Range::new(anchor, pos) + (Movement::Extend, Direction::Backward) => { + // Ensure a valid initial selection state. + let range = range.min_width_1(slice); + + // Do the main movement. + let mut head = nth_prev_grapheme_boundary(slice, range.head, count); + let mut anchor = range.anchor; + + // If the head and anchor crossed over each other, we need to + // fiddle around to make it behave like a 1-wide cursor. + if head <= anchor && range.head > range.anchor { + anchor = next_grapheme_boundary(slice, anchor); + head = prev_grapheme_boundary(slice, head); + } + + Range::new(anchor, head) + } + (Movement::Extend, Direction::Forward) => { + // Ensure a valid initial selection state. + let range = range.min_width_1(slice); + + // Do the main movement. + let mut head = nth_next_grapheme_boundary(slice, range.head, count); + let mut anchor = range.anchor; + + // If the head and anchor crossed over each other, we need to + // fiddle around to make it behave like a 1-wide cursor. + if head >= anchor && range.head < range.anchor { + anchor = prev_grapheme_boundary(slice, anchor); + head = next_grapheme_boundary(slice, head); + } + + Range::new(anchor, head) + } + } } pub fn move_vertically( @@ -57,36 +95,61 @@ pub fn move_vertically( count: usize, behaviour: Movement, ) -> Range { - let Position { row, col } = coords_at_pos(slice, range.head); + // Shift back one grapheme if needed, to account for + // the cursor being visually 1-width. + let pos = if range.head > range.anchor { + prev_grapheme_boundary(slice, range.head) + } else { + range.head + }; + // Compute the current position's 2d coordinates. + let Position { row, col } = coords_at_pos(slice, pos); let horiz = range.horiz.unwrap_or(col as u32); - let new_line = match dir { - Direction::Backward => row.saturating_sub(count), - Direction::Forward => std::cmp::min( - row.saturating_add(count), - slice.len_lines().saturating_sub(2), - ), - }; + // Compute the new position. + let new_pos = { + let new_row = if dir == Direction::Backward { + row.saturating_sub(count) + } else { + (row + count).min(slice.len_lines().saturating_sub(1)) + }; + let max_col = RopeGraphemes::new(line_without_line_ending(&slice, new_row)).count(); + let new_col = col.max(horiz as usize).min(max_col); - // Length of the line sans line-ending. - let new_line_len = { - let line = slice.line(new_line); - line.len_chars() - get_line_ending(&line).map(|le| le.len_chars()).unwrap_or(0) + pos_at_coords(slice, Position::new(new_row, new_col)) }; - let new_col = std::cmp::min(horiz as usize, new_line_len); - - let pos = pos_at_coords(slice, Position::new(new_line, new_col)); + // Compute the new range according to the type of movement. + match behaviour { + Movement::Move => Range { + anchor: new_pos, + head: new_pos, + horiz: Some(horiz), + }, + + Movement::Extend => { + let new_head = if new_pos >= range.anchor { + next_grapheme_boundary(slice, new_pos) + } else { + new_pos + }; - let anchor = match behaviour { - Movement::Extend => range.anchor, - Movement::Move => pos, - }; + let new_anchor = if range.anchor <= range.head && range.anchor > new_head { + next_grapheme_boundary(slice, range.anchor) + } else if range.anchor > range.head && range.anchor < new_head { + prev_grapheme_boundary(slice, range.anchor) + } else { + range.anchor + }; - let mut range = Range::new(anchor, pos); - range.horiz = Some(horiz); - range + Range { + anchor: new_anchor, + head: new_head, + horiz: Some(horiz), + } + } + } } pub fn move_next_word_start(slice: RopeSlice, range: Range, count: usize) -> Range { @@ -330,7 +393,7 @@ mod test { } #[test] - fn horizontal_moves_through_single_line_in_single_line_text() { + fn horizontal_moves_through_single_line_text() { let text = Rope::from(SINGLE_LINE_SAMPLE); let slice = text.slice(..); let position = pos_at_coords(slice, (0, 0).into()); @@ -353,7 +416,7 @@ mod test { } #[test] - fn horizontal_moves_through_single_line_in_multiline_text() { + fn horizontal_moves_through_multiline_text() { let text = Rope::from(MULTILINE_SAMPLE); let slice = text.slice(..); let position = pos_at_coords(slice, (0, 0).into()); @@ -361,15 +424,15 @@ mod test { let mut range = Range::point(position); let moves_and_expected_coordinates = IntoIter::new([ - ((Direction::Forward, 1usize), (0, 1)), // M|ultiline\n - ((Direction::Forward, 2usize), (0, 3)), // Mul|tiline\n - ((Direction::Backward, 6usize), (0, 0)), // |Multiline\n - ((Direction::Backward, 999usize), (0, 0)), // |Multiline\n - ((Direction::Forward, 3usize), (0, 3)), // Mul|tiline\n - ((Direction::Forward, 0usize), (0, 3)), // Mul|tiline\n - ((Direction::Backward, 0usize), (0, 3)), // Mul|tiline\n - ((Direction::Forward, 999usize), (0, 9)), // Multiline|\n - ((Direction::Forward, 999usize), (0, 9)), // Multiline|\n + ((Direction::Forward, 11usize), (1, 1)), // Multiline\nt|ext sample\n... + ((Direction::Backward, 1usize), (1, 0)), // Multiline\n|text sample\n... + ((Direction::Backward, 5usize), (0, 5)), // Multi|line\ntext sample\n... + ((Direction::Backward, 999usize), (0, 0)), // |Multiline\ntext sample\n... + ((Direction::Forward, 3usize), (0, 3)), // Mul|tiline\ntext sample\n... + ((Direction::Forward, 0usize), (0, 3)), // Mul|tiline\ntext sample\n... + ((Direction::Backward, 0usize), (0, 3)), // Mul|tiline\ntext sample\n... + ((Direction::Forward, 999usize), (5, 0)), // ...and whitespaced\n| + ((Direction::Forward, 999usize), (5, 0)), // ...and whitespaced\n| ]); for ((direction, amount), coordinates) in moves_and_expected_coordinates { @@ -409,12 +472,13 @@ mod test { let moves_and_expected_coordinates = IntoIter::new([ ((Direction::Forward, 1usize), (1, 0)), ((Direction::Forward, 2usize), (3, 0)), + ((Direction::Forward, 1usize), (4, 0)), ((Direction::Backward, 999usize), (0, 0)), - ((Direction::Forward, 3usize), (3, 0)), - ((Direction::Forward, 0usize), (3, 0)), - ((Direction::Backward, 0usize), (3, 0)), - ((Direction::Forward, 5), (4, 0)), - ((Direction::Forward, 999usize), (4, 0)), + ((Direction::Forward, 4usize), (4, 0)), + ((Direction::Forward, 0usize), (4, 0)), + ((Direction::Backward, 0usize), (4, 0)), + ((Direction::Forward, 5), (5, 0)), + ((Direction::Forward, 999usize), (5, 0)), ]); for ((direction, amount), coordinates) in moves_and_expected_coordinates { @@ -446,7 +510,8 @@ mod test { ((Axis::V, Direction::Forward, 1usize), (3, 8)), // Behaviour is preserved even through long jumps ((Axis::V, Direction::Backward, 999usize), (0, 8)), - ((Axis::V, Direction::Forward, 999usize), (4, 8)), + ((Axis::V, Direction::Forward, 4usize), (4, 8)), + ((Axis::V, Direction::Forward, 999usize), (5, 0)), ]); for ((axis, direction, amount), coordinates) in moves_and_expected_coordinates { |