Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'lib/line-index/src/lib.rs')
| -rw-r--r-- | lib/line-index/src/lib.rs | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/lib/line-index/src/lib.rs b/lib/line-index/src/lib.rs index ad6a79c409..214fc215f6 100644 --- a/lib/line-index/src/lib.rs +++ b/lib/line-index/src/lib.rs @@ -83,7 +83,7 @@ impl WideChar { /// Maps flat [`TextSize`] offsets to/from `(line, column)` representation. #[derive(Debug, Clone, PartialEq, Eq)] pub struct LineIndex { - /// Offset the beginning of each line, zero-based. + /// Offset the beginning of each line (except the first, which always has offset 0). newlines: Box<[TextSize]>, /// List of non-ASCII characters on each line. line_wide_chars: IntMap<u32, Box<[WideChar]>>, @@ -100,8 +100,6 @@ impl LineIndex { let mut cur_col = TextSize::from(0); let mut line = 0; - newlines.push(TextSize::from(0)); - for c in text.chars() { let c_len = TextSize::of(c); cur_row += c_len; @@ -147,8 +145,8 @@ impl LineIndex { /// Transforms the `TextSize` into a `LineCol`, or returns `None` if the `offset` was invalid, /// e.g. if it points to the middle of a multi-byte character. pub fn try_line_col(&self, offset: TextSize) -> Option<LineCol> { - let line = self.newlines.partition_point(|&it| it <= offset).checked_sub(1)?; - let start = self.newlines.get(line)?; + let line = self.newlines.partition_point(|&it| it <= offset); + let start = self.start_offset(line)?; let col = offset - start; let ret = LineCol { line: line as u32, col: col.into() }; self.line_wide_chars @@ -162,9 +160,14 @@ impl LineIndex { /// Transforms the `LineCol` into a `TextSize`. pub fn offset(&self, line_col: LineCol) -> Option<TextSize> { - self.newlines - .get(line_col.line as usize) - .map(|offset| offset + TextSize::from(line_col.col)) + self.start_offset(line_col.line as usize).map(|start| start + TextSize::from(line_col.col)) + } + + fn start_offset(&self, line: usize) -> Option<TextSize> { + match line.checked_sub(1) { + None => Some(TextSize::from(0)), + Some(it) => self.newlines.get(it).copied(), + } } /// Transforms the `LineCol` with the given `WideEncoding` into a `WideLineCol`. |