Inline implementation of lookup_line

to simplify the implementation and avoid unnecessary
conversions from `Option<usize>` to `isize` and back.
This commit is contained in:
Tomasz Miąsko 2021-07-05 00:00:00 +00:00
parent aa65b08b1d
commit 1719d45013
2 changed files with 16 additions and 25 deletions

View File

@ -1552,13 +1552,11 @@ pub fn count_lines(&self) -> usize {
/// number. If the source_file is empty or the position is located before the
/// first line, `None` is returned.
pub fn lookup_line(&self, pos: BytePos) -> Option<usize> {
if self.lines.is_empty() {
return None;
match self.lines.binary_search(&pos) {
Ok(idx) => Some(idx),
Err(0) => None,
Err(idx) => Some(idx - 1),
}
let line_index = lookup_line(&self.lines[..], pos);
assert!(line_index < self.lines.len() as isize);
if line_index >= 0 { Some(line_index as usize) } else { None }
}
pub fn line_bounds(&self, line_index: usize) -> Range<BytePos> {
@ -1957,16 +1955,6 @@ pub fn new(start: usize, end: usize) -> InnerSpan {
}
}
// Given a slice of line start positions and a position, returns the index of
// the line the position is on. Returns -1 if the position is located before
// the first line.
fn lookup_line(lines: &[BytePos], pos: BytePos) -> isize {
match lines.binary_search(&pos) {
Ok(line) => line as isize,
Err(line) => line as isize - 1,
}
}
/// Requirements for a `StableHashingContext` to be used in this crate.
///
/// This is a hack to allow using the [`HashStable_Generic`] derive macro

View File

@ -2,18 +2,21 @@
#[test]
fn test_lookup_line() {
let lines = &[BytePos(3), BytePos(17), BytePos(28)];
let source = "abcdefghijklm\nabcdefghij\n...".to_owned();
let sf =
SourceFile::new(FileName::Anon(0), source, BytePos(3), SourceFileHashAlgorithm::Sha256);
assert_eq!(sf.lines.as_slice(), &[BytePos(3), BytePos(17), BytePos(28)]);
assert_eq!(lookup_line(lines, BytePos(0)), -1);
assert_eq!(lookup_line(lines, BytePos(3)), 0);
assert_eq!(lookup_line(lines, BytePos(4)), 0);
assert_eq!(sf.lookup_line(BytePos(0)), None);
assert_eq!(sf.lookup_line(BytePos(3)), Some(0));
assert_eq!(sf.lookup_line(BytePos(4)), Some(0));
assert_eq!(lookup_line(lines, BytePos(16)), 0);
assert_eq!(lookup_line(lines, BytePos(17)), 1);
assert_eq!(lookup_line(lines, BytePos(18)), 1);
assert_eq!(sf.lookup_line(BytePos(16)), Some(0));
assert_eq!(sf.lookup_line(BytePos(17)), Some(1));
assert_eq!(sf.lookup_line(BytePos(18)), Some(1));
assert_eq!(lookup_line(lines, BytePos(28)), 2);
assert_eq!(lookup_line(lines, BytePos(29)), 2);
assert_eq!(sf.lookup_line(BytePos(28)), Some(2));
assert_eq!(sf.lookup_line(BytePos(29)), Some(2));
}
#[test]