use crate::source_map::SourceMap;
use crate::{BytePos, SourceFile};
use rustc_data_structures::sync::Lrc;
+use std::ops::Range;
#[derive(Clone)]
struct CacheEntry {
time_stamp: usize,
line_number: usize,
- line_start: BytePos,
- line_end: BytePos,
+ // The line's byte position range in the `SourceMap`. This range will fail to contain a valid
+ // position in certain edge cases. Spans often start/end one past something, and when that
+ // something is the last character of a file (this can happen when a file doesn't end in a
+ // newline, for example), we'd still like for the position to be considered within the last
+ // line. However, it isn't according to the exclusive upper bound of this range. We cannot
+ // change the upper bound to be inclusive, because for most lines, the upper bound is the same
+ // as the lower bound of the next line, so there would be an ambiguity.
+ //
+ // Since the containment aspect of this range is only used to see whether or not the cache
+ // entry contains a position, the only ramification of the above is that we will get cache
+ // misses for these rare positions. A line lookup for the position via `SourceMap::lookup_line`
+ // after a cache miss will produce the last line number, as desired.
+ line: Range<BytePos>,
file: Lrc<SourceFile>,
file_index: usize,
}
let entry = CacheEntry {
time_stamp: 0,
line_number: 0,
- line_start: BytePos(0),
- line_end: BytePos(0),
+ line: BytePos(0)..BytePos(0),
file: first_file,
file_index: 0,
};
// Check if the position is in one of the cached lines
for cache_entry in self.line_cache.iter_mut() {
- if line_contains((cache_entry.line_start, cache_entry.line_end), pos) {
+ if cache_entry.line.contains(&pos) {
cache_entry.time_stamp = self.time_stamp;
return Some((
cache_entry.file.clone(),
cache_entry.line_number,
- pos - cache_entry.line_start,
+ pos - cache_entry.line.start,
));
}
}
let line_bounds = cache_entry.file.line_bounds(line_index);
cache_entry.line_number = line_index + 1;
- cache_entry.line_start = line_bounds.0;
- cache_entry.line_end = line_bounds.1;
+ cache_entry.line = line_bounds;
cache_entry.time_stamp = self.time_stamp;
- Some((cache_entry.file.clone(), cache_entry.line_number, pos - cache_entry.line_start))
+ Some((cache_entry.file.clone(), cache_entry.line_number, pos - cache_entry.line.start))
}
}
-#[inline]
-fn line_contains(line_bounds: (BytePos, BytePos), pos: BytePos) -> bool {
- // This condition will be false in one case where we'd rather it wasn't. Spans often start/end
- // one past something, and when that something is the last character of a file (this can happen
- // when a file doesn't end in a newline, for example), we'd still like for the position to be
- // considered within the last line. However, it isn't according to the exclusive upper bound
- // below. We cannot change the upper bound to be inclusive, because for most lines, the upper
- // bound is the same as the lower bound of the next line, so there would be an ambiguity.
- //
- // Supposing we only use this function to check whether or not the line cache entry contains
- // a position, the only ramification of the above is that we will get cache misses for these
- // rare positions. A line lookup for the position via `SourceMap::lookup_line` after a cache
- // miss will produce the last line number, as desired.
- line_bounds.0 <= pos && pos < line_bounds.1
-}
-
#[inline]
fn file_contains(file: &SourceFile, pos: BytePos) -> bool {
// `SourceMap::lookup_source_file_idx` and `SourceFile::contains` both consider the position
use std::cmp::{self, Ordering};
use std::fmt;
use std::hash::Hash;
-use std::ops::{Add, Sub};
+use std::ops::{Add, Range, Sub};
use std::path::{Path, PathBuf};
use std::str::FromStr;
if line_index >= 0 { Some(line_index as usize) } else { None }
}
- pub fn line_bounds(&self, line_index: usize) -> (BytePos, BytePos) {
+ pub fn line_bounds(&self, line_index: usize) -> Range<BytePos> {
if self.is_empty() {
- return (self.start_pos, self.end_pos);
+ return self.start_pos..self.end_pos;
}
assert!(line_index < self.lines.len());
if line_index == (self.lines.len() - 1) {
- (self.lines[line_index], self.end_pos)
+ self.lines[line_index]..self.end_pos
} else {
- (self.lines[line_index], self.lines[line_index + 1])
+ self.lines[line_index]..self.lines[line_index + 1]
}
}