diff options
Diffstat (limited to 'helix-core/src')
| -rw-r--r-- | helix-core/src/surround.rs | 111 |
1 files changed, 73 insertions, 38 deletions
diff --git a/helix-core/src/surround.rs b/helix-core/src/surround.rs index 58eb23cf..c14456b7 100644 --- a/helix-core/src/surround.rs +++ b/helix-core/src/surround.rs @@ -1,3 +1,5 @@ +use std::fmt::Display; + use crate::{search, Range, Selection}; use ropey::RopeSlice; @@ -11,6 +13,27 @@ pub const PAIRS: &[(char, char)] = &[ ('（', '）'), ]; +#[derive(Debug, PartialEq)] +pub enum Error { + PairNotFound, + CursorOverlap, + RangeExceedsText, + CursorOnAmbiguousPair, +} + +impl Display for Error { + fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { + f.write_str(match *self { + Error::PairNotFound => "Surround pair not found around all cursors", + Error::CursorOverlap => "Cursors overlap for a single surround pair range", + Error::RangeExceedsText => "Cursor range exceeds text length", + Error::CursorOnAmbiguousPair => "Cursor on ambiguous surround pair", + }) + } +} + +type Result<T> = std::result::Result<T, Error>; + /// Given any char in [PAIRS], return the open and closing chars. If not found in /// [PAIRS] return (ch, ch). /// @@ -37,31 +60,36 @@ pub fn find_nth_pairs_pos( ch: char, range: Range, n: usize, -) -> Option<(usize, usize)> { - if text.len_chars() < 2 || range.to() >= text.len_chars() { - return None; +) -> Result<(usize, usize)> { + if text.len_chars() < 2 { + return Err(Error::PairNotFound); + } + if range.to() >= text.len_chars() { + return Err(Error::RangeExceedsText); } let (open, close) = get_pair(ch); let pos = range.cursor(text); - if open == close { + let (open, close) = if open == close { if Some(open) == text.get_char(pos) { // Cursor is directly on match char. We return no match // because there's no way to know which side of the char // we should be searching on. - return None; + return Err(Error::CursorOnAmbiguousPair); } - Some(( - search::find_nth_prev(text, open, pos, n)?, - search::find_nth_next(text, close, pos, n)?, - )) + ( + search::find_nth_prev(text, open, pos, n), + search::find_nth_next(text, close, pos, n), + ) } else { - Some(( - find_nth_open_pair(text, open, close, pos, n)?, - find_nth_close_pair(text, open, close, pos, n)?, - )) - } + ( + find_nth_open_pair(text, open, close, pos, n), + find_nth_close_pair(text, open, close, pos, n), + ) + }; + + Option::zip(open, close).ok_or(Error::PairNotFound) } fn find_nth_open_pair( @@ -151,17 +179,17 @@ pub fn get_surround_pos( selection: &Selection, ch: char, skip: usize, -) -> Option<Vec<usize>> { +) -> Result<Vec<usize>> { let mut change_pos = Vec::new(); for &range in selection { let (open_pos, close_pos) = find_nth_pairs_pos(text, ch, range, skip)?; if change_pos.contains(&open_pos) || change_pos.contains(&close_pos) { - return None; + return Err(Error::CursorOverlap); } change_pos.extend_from_slice(&[open_pos, close_pos]); } - Some(change_pos) + Ok(change_pos) } #[cfg(test)] @@ -175,7 +203,7 @@ mod test { #[allow(clippy::type_complexity)] fn check_find_nth_pair_pos( text: &str, - cases: Vec<(usize, char, usize, Option<(usize, usize)>)>, + cases: Vec<(usize, char, usize, Result<(usize, usize)>)>, ) { let doc = Rope::from(text); let slice = doc.slice(..); @@ -196,13 +224,13 @@ mod test { "some (text) here", vec![ // cursor on [t]ext - (6, '(', 1, Some((5, 10))), - (6, ')', 1, Some((5, 10))), + (6, '(', 1, Ok((5, 10))), + (6, ')', 1, Ok((5, 10))), // cursor on so[m]e - (2, '(', 1, None), + (2, '(', 1, Err(Error::PairNotFound)), // cursor on bracket itself - (5, '(', 1, Some((5, 10))), - (10, '(', 1, Some((5, 10))), + (5, '(', 1, Ok((5, 10))), + (10, '(', 1, Ok((5, 10))), ], ); } @@ -213,9 +241,9 @@ mod test { "(so (many (good) text) here)", vec![ // cursor on go[o]d - (13, '(', 1, Some((10, 15))), - (13, '(', 2, Some((4, 21))), - (13, '(', 3, Some((0, 27))), + (13, '(', 1, Ok((10, 15))), + (13, '(', 2, Ok((4, 21))), + (13, '(', 3, Ok((0, 27))), ], ); } @@ -226,11 +254,11 @@ mod test { "'so 'many 'good' text' here'", vec![ // cursor on go[o]d - (13, '\'', 1, Some((10, 15))), - (13, '\'', 2, Some((4, 21))), - (13, '\'', 3, Some((0, 27))), + (13, '\'', 1, Ok((10, 15))), + (13, '\'', 2, Ok((4, 21))), + (13, '\'', 3, Ok((0, 27))), // cursor on the quotes - (10, '\'', 1, None), + (10, '\'', 1, Err(Error::CursorOnAmbiguousPair)), ], ) } @@ -241,8 +269,8 @@ mod test { "((so)((many) good (text))(here))", vec![ // cursor on go[o]d - (15, '(', 1, Some((5, 24))), - (15, '(', 2, Some((0, 31))), + (15, '(', 1, Ok((5, 24))), + (15, '(', 2, Ok((0, 31))), ], ) } @@ -253,9 +281,9 @@ mod test { "(so [many {good} text] here)", vec![ // cursor on go[o]d - (13, '{', 1, Some((10, 15))), - (13, '[', 1, Some((4, 21))), - (13, '(', 1, Some((0, 27))), + (13, '{', 1, Ok((10, 15))), + (13, '[', 1, Ok((4, 21))), + (13, '(', 1, Ok((0, 27))), ], ) } @@ -285,11 +313,10 @@ mod test { let selection = Selection::new(SmallVec::from_slice(&[Range::point(2), Range::point(9)]), 0); - // cursor on s[o]me, c[h]ars assert_eq!( get_surround_pos(slice, &selection, '(', 1), - None // different surround chars + Err(Error::PairNotFound) // different surround chars ); let selection = Selection::new( @@ -299,7 +326,15 @@ mod test { // cursor on [x]x, newli[n]e assert_eq!( get_surround_pos(slice, &selection, '(', 1), - None // overlapping surround chars + Err(Error::PairNotFound) // overlapping surround chars + ); + + let selection = + Selection::new(SmallVec::from_slice(&[Range::point(2), Range::point(3)]), 0); + // cursor on s[o][m]e + assert_eq!( + get_surround_pos(slice, &selection, '[', 1), + Err(Error::CursorOverlap) ); } } |