Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide-db/src/line_index.rs')
| -rw-r--r-- | crates/ide-db/src/line_index.rs | 314 |
1 files changed, 0 insertions, 314 deletions
diff --git a/crates/ide-db/src/line_index.rs b/crates/ide-db/src/line_index.rs deleted file mode 100644 index 16814a1e63..0000000000 --- a/crates/ide-db/src/line_index.rs +++ /dev/null @@ -1,314 +0,0 @@ -//! `LineIndex` maps flat `TextSize` offsets into `(Line, Column)` -//! representation. -use std::{iter, mem}; - -use stdx::hash::NoHashHashMap; -use syntax::{TextRange, TextSize}; - -#[derive(Clone, Debug, PartialEq, Eq)] -pub struct LineIndex { - /// Offset the beginning of each line, zero-based. - pub(crate) newlines: Vec<TextSize>, - /// List of non-ASCII characters on each line. - pub(crate) line_wide_chars: NoHashHashMap<u32, Vec<WideChar>>, -} - -/// Line/Column information in native, utf8 format. -#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)] -pub struct LineCol { - /// Zero-based - pub line: u32, - /// Zero-based utf8 offset - pub col: u32, -} - -#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)] -pub enum WideEncoding { - Utf16, - Utf32, -} - -/// Line/Column information in legacy encodings. -/// -/// Deliberately not a generic type and different from `LineCol`. -#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)] -pub struct WideLineCol { - /// Zero-based - pub line: u32, - /// Zero-based - pub col: u32, -} - -#[derive(Clone, Debug, Hash, PartialEq, Eq)] -pub(crate) struct WideChar { - /// Start offset of a character inside a line, zero-based - pub(crate) start: TextSize, - /// End offset of a character inside a line, zero-based - pub(crate) end: TextSize, -} - -impl WideChar { - /// Returns the length in 8-bit UTF-8 code units. - fn len(&self) -> TextSize { - self.end - self.start - } - - /// Returns the length in UTF-16 or UTF-32 code units. - fn wide_len(&self, enc: WideEncoding) -> usize { - match enc { - WideEncoding::Utf16 => { - if self.len() == TextSize::from(4) { - 2 - } else { - 1 - } - } - - WideEncoding::Utf32 => 1, - } - } -} - -impl LineIndex { - pub fn new(text: &str) -> LineIndex { - let mut line_wide_chars = NoHashHashMap::default(); - let mut wide_chars = Vec::new(); - - let mut newlines = Vec::with_capacity(16); - newlines.push(TextSize::from(0)); - - let mut curr_row = 0.into(); - let mut curr_col = 0.into(); - let mut line = 0; - for c in text.chars() { - let c_len = TextSize::of(c); - curr_row += c_len; - if c == '\n' { - newlines.push(curr_row); - - // Save any utf-16 characters seen in the previous line - if !wide_chars.is_empty() { - line_wide_chars.insert(line, mem::take(&mut wide_chars)); - } - - // Prepare for processing the next line - curr_col = 0.into(); - line += 1; - continue; - } - - if !c.is_ascii() { - wide_chars.push(WideChar { start: curr_col, end: curr_col + c_len }); - } - - curr_col += c_len; - } - - // Save any utf-16 characters seen in the last line - if !wide_chars.is_empty() { - line_wide_chars.insert(line, wide_chars); - } - - LineIndex { newlines, line_wide_chars } - } - - pub fn line_col(&self, offset: TextSize) -> LineCol { - let line = self.newlines.partition_point(|&it| it <= offset) - 1; - let line_start_offset = self.newlines[line]; - let col = offset - line_start_offset; - LineCol { line: line as u32, col: col.into() } - } - - 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)) - } - - pub fn to_wide(&self, enc: WideEncoding, line_col: LineCol) -> WideLineCol { - let col = self.utf8_to_wide_col(enc, line_col.line, line_col.col.into()); - WideLineCol { line: line_col.line, col: col as u32 } - } - - pub fn to_utf8(&self, enc: WideEncoding, line_col: WideLineCol) -> LineCol { - let col = self.wide_to_utf8_col(enc, line_col.line, line_col.col); - LineCol { line: line_col.line, col: col.into() } - } - - pub fn lines(&self, range: TextRange) -> impl Iterator<Item = TextRange> + '_ { - let lo = self.newlines.partition_point(|&it| it < range.start()); - let hi = self.newlines.partition_point(|&it| it <= range.end()); - let all = iter::once(range.start()) - .chain(self.newlines[lo..hi].iter().copied()) - .chain(iter::once(range.end())); - - all.clone() - .zip(all.skip(1)) - .map(|(lo, hi)| TextRange::new(lo, hi)) - .filter(|it| !it.is_empty()) - } - - fn utf8_to_wide_col(&self, enc: WideEncoding, line: u32, col: TextSize) -> usize { - let mut res: usize = col.into(); - if let Some(wide_chars) = self.line_wide_chars.get(&line) { - for c in wide_chars { - if c.end <= col { - res -= usize::from(c.len()) - c.wide_len(enc); - } else { - // From here on, all utf16 characters come *after* the character we are mapping, - // so we don't need to take them into account - break; - } - } - } - res - } - - fn wide_to_utf8_col(&self, enc: WideEncoding, line: u32, mut col: u32) -> TextSize { - if let Some(wide_chars) = self.line_wide_chars.get(&line) { - for c in wide_chars { - if col > u32::from(c.start) { - col += u32::from(c.len()) - c.wide_len(enc) as u32; - } else { - // From here on, all utf16 characters come *after* the character we are mapping, - // so we don't need to take them into account - break; - } - } - } - - col.into() - } -} - -#[cfg(test)] -mod tests { - use test_utils::skip_slow_tests; - - use super::WideEncoding::{Utf16, Utf32}; - use super::*; - - #[test] - fn test_line_index() { - let text = "hello\nworld"; - let table = [ - (00, 0, 0), - (01, 0, 1), - (05, 0, 5), - (06, 1, 0), - (07, 1, 1), - (08, 1, 2), - (10, 1, 4), - (11, 1, 5), - (12, 1, 6), - ]; - - let index = LineIndex::new(text); - for (offset, line, col) in table { - assert_eq!(index.line_col(offset.into()), LineCol { line, col }); - } - - let text = "\nhello\nworld"; - let table = [(0, 0, 0), (1, 1, 0), (2, 1, 1), (6, 1, 5), (7, 2, 0)]; - let index = LineIndex::new(text); - for (offset, line, col) in table { - assert_eq!(index.line_col(offset.into()), LineCol { line, col }); - } - } - - #[test] - fn test_char_len() { - assert_eq!('メ'.len_utf8(), 3); - assert_eq!('メ'.len_utf16(), 1); - } - - #[test] - fn test_empty_index() { - let col_index = LineIndex::new( - " -const C: char = 'x'; -", - ); - assert_eq!(col_index.line_wide_chars.len(), 0); - } - - #[test] - fn test_every_chars() { - if skip_slow_tests() { - return; - } - - let text: String = { - let mut chars: Vec<char> = ((0 as char)..char::MAX).collect(); // Neat! - chars.extend("\n".repeat(chars.len() / 16).chars()); - let mut rng = oorandom::Rand32::new(stdx::rand::seed()); - stdx::rand::shuffle(&mut chars, |i| rng.rand_range(0..i as u32) as usize); - chars.into_iter().collect() - }; - assert!(text.contains('💩')); // Sanity check. - - let line_index = LineIndex::new(&text); - - let mut lin_col = LineCol { line: 0, col: 0 }; - let mut col_utf16 = 0; - let mut col_utf32 = 0; - for (offset, c) in text.char_indices() { - let got_offset = line_index.offset(lin_col).unwrap(); - assert_eq!(usize::from(got_offset), offset); - - let got_lin_col = line_index.line_col(got_offset); - assert_eq!(got_lin_col, lin_col); - - for enc in [Utf16, Utf32] { - let wide_lin_col = line_index.to_wide(enc, lin_col); - let got_lin_col = line_index.to_utf8(enc, wide_lin_col); - assert_eq!(got_lin_col, lin_col); - - let want_col = match enc { - Utf16 => col_utf16, - Utf32 => col_utf32, - }; - assert_eq!(wide_lin_col.col, want_col) - } - - if c == '\n' { - lin_col.line += 1; - lin_col.col = 0; - col_utf16 = 0; - col_utf32 = 0; - } else { - lin_col.col += c.len_utf8() as u32; - col_utf16 += c.len_utf16() as u32; - col_utf32 += 1; - } - } - } - - #[test] - fn test_splitlines() { - fn r(lo: u32, hi: u32) -> TextRange { - TextRange::new(lo.into(), hi.into()) - } - - let text = "a\nbb\nccc\n"; - let line_index = LineIndex::new(text); - - let actual = line_index.lines(r(0, 9)).collect::<Vec<_>>(); - let expected = vec![r(0, 2), r(2, 5), r(5, 9)]; - assert_eq!(actual, expected); - - let text = ""; - let line_index = LineIndex::new(text); - - let actual = line_index.lines(r(0, 0)).collect::<Vec<_>>(); - let expected = vec![]; - assert_eq!(actual, expected); - - let text = "\n"; - let line_index = LineIndex::new(text); - - let actual = line_index.lines(r(0, 1)).collect::<Vec<_>>(); - let expected = vec![r(0, 1)]; - assert_eq!(actual, expected) - } -} |