mirror of
https://github.com/astral-sh/ruff.git
synced 2025-09-28 12:55:05 +00:00
468 lines
16 KiB
Rust
468 lines
16 KiB
Rust
//! Struct used to efficiently slice source code at (row, column) Locations.
|
||
|
||
use std::ops::Add;
|
||
|
||
use memchr::{memchr2, memrchr2};
|
||
use once_cell::unsync::OnceCell;
|
||
use ruff_text_size::{Ranged, TextLen, TextRange, TextSize};
|
||
|
||
use crate::newlines::find_newline;
|
||
use crate::{LineIndex, OneIndexed, SourceCode, SourceLocation};
|
||
|
||
pub struct Locator<'a> {
|
||
contents: &'a str,
|
||
index: OnceCell<LineIndex>,
|
||
}
|
||
|
||
impl<'a> Locator<'a> {
|
||
pub const fn new(contents: &'a str) -> Self {
|
||
Self {
|
||
contents,
|
||
index: OnceCell::new(),
|
||
}
|
||
}
|
||
|
||
#[deprecated(
|
||
note = "This is expensive, avoid using outside of the diagnostic phase. Prefer the other `Locator` methods instead."
|
||
)]
|
||
pub fn compute_line_index(&self, offset: TextSize) -> OneIndexed {
|
||
self.to_index().line_index(offset)
|
||
}
|
||
|
||
#[deprecated(
|
||
note = "This is expensive, avoid using outside of the diagnostic phase. Prefer the other `Locator` methods instead."
|
||
)]
|
||
pub fn compute_source_location(&self, offset: TextSize) -> SourceLocation {
|
||
self.to_source_code().source_location(offset)
|
||
}
|
||
|
||
fn to_index(&self) -> &LineIndex {
|
||
self.index
|
||
.get_or_init(|| LineIndex::from_source_text(self.contents))
|
||
}
|
||
|
||
pub fn line_index(&self) -> Option<&LineIndex> {
|
||
self.index.get()
|
||
}
|
||
|
||
pub fn to_source_code(&self) -> SourceCode {
|
||
SourceCode {
|
||
index: self.to_index(),
|
||
text: self.contents,
|
||
}
|
||
}
|
||
|
||
/// Computes the start position of the line of `offset`.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::TextSize;
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\rthird line");
|
||
///
|
||
/// assert_eq!(locator.line_start(TextSize::from(0)), TextSize::from(0));
|
||
/// assert_eq!(locator.line_start(TextSize::from(4)), TextSize::from(0));
|
||
///
|
||
/// assert_eq!(locator.line_start(TextSize::from(14)), TextSize::from(11));
|
||
/// assert_eq!(locator.line_start(TextSize::from(28)), TextSize::from(23));
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If `offset` is out of bounds.
|
||
pub fn line_start(&self, offset: TextSize) -> TextSize {
|
||
let bytes = self.contents[TextRange::up_to(offset)].as_bytes();
|
||
if let Some(index) = memrchr2(b'\n', b'\r', bytes) {
|
||
// SAFETY: Safe because `index < offset`
|
||
TextSize::try_from(index).unwrap().add(TextSize::from(1))
|
||
} else if self.contents.starts_with('\u{feff}') {
|
||
// Skip the BOM.
|
||
'\u{feff}'.text_len()
|
||
} else {
|
||
// Start of file.
|
||
TextSize::default()
|
||
}
|
||
}
|
||
|
||
pub fn is_at_start_of_line(&self, offset: TextSize) -> bool {
|
||
offset == TextSize::from(0)
|
||
|| self.contents[TextRange::up_to(offset)].ends_with(['\n', '\r'])
|
||
}
|
||
|
||
/// Computes the offset that is right after the newline character that ends `offset`'s line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(locator.full_line_end(TextSize::from(3)), TextSize::from(11));
|
||
/// assert_eq!(locator.full_line_end(TextSize::from(14)), TextSize::from(24));
|
||
/// assert_eq!(locator.full_line_end(TextSize::from(28)), TextSize::from(34));
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
///
|
||
/// If `offset` is passed the end of the content.
|
||
pub fn full_line_end(&self, offset: TextSize) -> TextSize {
|
||
let slice = &self.contents[usize::from(offset)..];
|
||
if let Some((index, line_ending)) = find_newline(slice) {
|
||
offset + TextSize::try_from(index).unwrap() + line_ending.text_len()
|
||
} else {
|
||
self.contents.text_len()
|
||
}
|
||
}
|
||
|
||
/// Computes the offset that is right before the newline character that ends `offset`'s line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(locator.line_end(TextSize::from(3)), TextSize::from(10));
|
||
/// assert_eq!(locator.line_end(TextSize::from(14)), TextSize::from(22));
|
||
/// assert_eq!(locator.line_end(TextSize::from(28)), TextSize::from(34));
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
///
|
||
/// If `offset` is passed the end of the content.
|
||
pub fn line_end(&self, offset: TextSize) -> TextSize {
|
||
let slice = &self.contents[usize::from(offset)..];
|
||
if let Some(index) = memchr2(b'\n', b'\r', slice.as_bytes()) {
|
||
offset + TextSize::try_from(index).unwrap()
|
||
} else {
|
||
self.contents.text_len()
|
||
}
|
||
}
|
||
|
||
/// Computes the range of this `offset`s line.
|
||
///
|
||
/// The range starts at the beginning of the line and goes up to, and including, the new line character
|
||
/// at the end of the line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(locator.full_line_range(TextSize::from(3)), TextRange::new(TextSize::from(0), TextSize::from(11)));
|
||
/// assert_eq!(locator.full_line_range(TextSize::from(14)), TextRange::new(TextSize::from(11), TextSize::from(24)));
|
||
/// assert_eq!(locator.full_line_range(TextSize::from(28)), TextRange::new(TextSize::from(24), TextSize::from(34)));
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If `offset` is out of bounds.
|
||
pub fn full_line_range(&self, offset: TextSize) -> TextRange {
|
||
TextRange::new(self.line_start(offset), self.full_line_end(offset))
|
||
}
|
||
|
||
/// Computes the range of this `offset`s line ending before the newline character.
|
||
///
|
||
/// The range starts at the beginning of the line and goes up to, but excluding, the new line character
|
||
/// at the end of the line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(locator.line_range(TextSize::from(3)), TextRange::new(TextSize::from(0), TextSize::from(10)));
|
||
/// assert_eq!(locator.line_range(TextSize::from(14)), TextRange::new(TextSize::from(11), TextSize::from(22)));
|
||
/// assert_eq!(locator.line_range(TextSize::from(28)), TextRange::new(TextSize::from(24), TextSize::from(34)));
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If `offset` is out of bounds.
|
||
pub fn line_range(&self, offset: TextSize) -> TextRange {
|
||
TextRange::new(self.line_start(offset), self.line_end(offset))
|
||
}
|
||
|
||
/// Returns the text of the `offset`'s line.
|
||
///
|
||
/// The line includes the newline characters at the end of the line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(locator.full_line(TextSize::from(3)), "First line\n");
|
||
/// assert_eq!(locator.full_line(TextSize::from(14)), "second line\r\n");
|
||
/// assert_eq!(locator.full_line(TextSize::from(28)), "third line");
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If `offset` is out of bounds.
|
||
pub fn full_line(&self, offset: TextSize) -> &'a str {
|
||
&self.contents[self.full_line_range(offset)]
|
||
}
|
||
|
||
/// Returns the text of the `offset`'s line.
|
||
///
|
||
/// Excludes the newline characters at the end of the line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(locator.line(TextSize::from(3)), "First line");
|
||
/// assert_eq!(locator.line(TextSize::from(14)), "second line");
|
||
/// assert_eq!(locator.line(TextSize::from(28)), "third line");
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If `offset` is out of bounds.
|
||
pub fn line(&self, offset: TextSize) -> &'a str {
|
||
&self.contents[self.line_range(offset)]
|
||
}
|
||
|
||
/// Computes the range of all lines that this `range` covers.
|
||
///
|
||
/// The range starts at the beginning of the line at `range.start()` and goes up to, and including, the new line character
|
||
/// at the end of `range.ends()`'s line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.full_lines_range(TextRange::new(TextSize::from(3), TextSize::from(5))),
|
||
/// TextRange::new(TextSize::from(0), TextSize::from(11))
|
||
/// );
|
||
/// assert_eq!(
|
||
/// locator.full_lines_range(TextRange::new(TextSize::from(3), TextSize::from(14))),
|
||
/// TextRange::new(TextSize::from(0), TextSize::from(24))
|
||
/// );
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If the start or end of `range` is out of bounds.
|
||
pub fn full_lines_range(&self, range: TextRange) -> TextRange {
|
||
TextRange::new(
|
||
self.line_start(range.start()),
|
||
self.full_line_end(range.end()),
|
||
)
|
||
}
|
||
|
||
/// Computes the range of all lines that this `range` covers.
|
||
///
|
||
/// The range starts at the beginning of the line at `range.start()` and goes up to, but excluding, the new line character
|
||
/// at the end of `range.end()`'s line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.lines_range(TextRange::new(TextSize::from(3), TextSize::from(5))),
|
||
/// TextRange::new(TextSize::from(0), TextSize::from(10))
|
||
/// );
|
||
/// assert_eq!(
|
||
/// locator.lines_range(TextRange::new(TextSize::from(3), TextSize::from(14))),
|
||
/// TextRange::new(TextSize::from(0), TextSize::from(22))
|
||
/// );
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If the start or end of `range` is out of bounds.
|
||
pub fn lines_range(&self, range: TextRange) -> TextRange {
|
||
TextRange::new(self.line_start(range.start()), self.line_end(range.end()))
|
||
}
|
||
|
||
/// Returns true if the text of `range` contains any line break.
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert!(
|
||
/// !locator.contains_line_break(TextRange::new(TextSize::from(3), TextSize::from(5))),
|
||
/// );
|
||
/// assert!(
|
||
/// locator.contains_line_break(TextRange::new(TextSize::from(3), TextSize::from(14))),
|
||
/// );
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If the `range` is out of bounds.
|
||
pub fn contains_line_break(&self, range: TextRange) -> bool {
|
||
let text = &self.contents[range];
|
||
text.contains(['\n', '\r'])
|
||
}
|
||
|
||
/// Returns the text of all lines that include `range`.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.lines(TextRange::new(TextSize::from(3), TextSize::from(5))),
|
||
/// "First line"
|
||
/// );
|
||
/// assert_eq!(
|
||
/// locator.lines(TextRange::new(TextSize::from(3), TextSize::from(14))),
|
||
/// "First line\nsecond line"
|
||
/// );
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If the start or end of `range` is out of bounds.
|
||
pub fn lines(&self, range: TextRange) -> &'a str {
|
||
&self.contents[self.lines_range(range)]
|
||
}
|
||
|
||
/// Returns the text of all lines that include `range`.
|
||
///
|
||
/// Includes the newline characters of the last line.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("First line\nsecond line\r\nthird line");
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.full_lines(TextRange::new(TextSize::from(3), TextSize::from(5))),
|
||
/// "First line\n"
|
||
/// );
|
||
/// assert_eq!(
|
||
/// locator.full_lines(TextRange::new(TextSize::from(3), TextSize::from(14))),
|
||
/// "First line\nsecond line\r\n"
|
||
/// );
|
||
/// ```
|
||
///
|
||
/// ## Panics
|
||
/// If the start or end of `range` is out of bounds.
|
||
pub fn full_lines(&self, range: TextRange) -> &'a str {
|
||
&self.contents[self.full_lines_range(range)]
|
||
}
|
||
|
||
/// Take the source code up to the given [`TextSize`].
|
||
#[inline]
|
||
pub fn up_to(&self, offset: TextSize) -> &'a str {
|
||
&self.contents[TextRange::up_to(offset)]
|
||
}
|
||
|
||
/// Take the source code after the given [`TextSize`].
|
||
#[inline]
|
||
pub fn after(&self, offset: TextSize) -> &'a str {
|
||
&self.contents[usize::from(offset)..]
|
||
}
|
||
|
||
/// Finds the closest [`TextSize`] not exceeding the offset for which `is_char_boundary` is
|
||
/// `true`.
|
||
///
|
||
/// Can be replaced with `str::floor_char_boundary` once it's stable.
|
||
///
|
||
/// ## Examples
|
||
///
|
||
/// ```
|
||
/// # use ruff_text_size::{Ranged, TextRange, TextSize};
|
||
/// # use ruff_source_file::Locator;
|
||
///
|
||
/// let locator = Locator::new("Hello");
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.floor_char_boundary(TextSize::from(0)),
|
||
/// TextSize::from(0)
|
||
/// );
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.floor_char_boundary(TextSize::from(5)),
|
||
/// TextSize::from(5)
|
||
/// );
|
||
///
|
||
/// let locator = Locator::new("α");
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.floor_char_boundary(TextSize::from(0)),
|
||
/// TextSize::from(0)
|
||
/// );
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.floor_char_boundary(TextSize::from(1)),
|
||
/// TextSize::from(0)
|
||
/// );
|
||
///
|
||
/// assert_eq!(
|
||
/// locator.floor_char_boundary(TextSize::from(2)),
|
||
/// TextSize::from(2)
|
||
/// );
|
||
/// ```
|
||
pub fn floor_char_boundary(&self, offset: TextSize) -> TextSize {
|
||
if offset >= self.text_len() {
|
||
self.text_len()
|
||
} else {
|
||
// We know that the character boundary is within four bytes.
|
||
(0u32..=3u32)
|
||
.map(TextSize::from)
|
||
.filter_map(|index| offset.checked_sub(index))
|
||
.find(|offset| self.contents.is_char_boundary(offset.to_usize()))
|
||
.unwrap_or_default()
|
||
}
|
||
}
|
||
|
||
/// Take the source code between the given [`TextRange`].
|
||
#[inline]
|
||
pub fn slice<T: Ranged>(&self, ranged: T) -> &'a str {
|
||
&self.contents[ranged.range()]
|
||
}
|
||
|
||
/// Return the underlying source code.
|
||
pub fn contents(&self) -> &'a str {
|
||
self.contents
|
||
}
|
||
|
||
/// Return the number of bytes in the source code.
|
||
pub const fn len(&self) -> usize {
|
||
self.contents.len()
|
||
}
|
||
|
||
pub fn text_len(&self) -> TextSize {
|
||
self.contents.text_len()
|
||
}
|
||
|
||
/// Return `true` if the source code is empty.
|
||
pub const fn is_empty(&self) -> bool {
|
||
self.contents.is_empty()
|
||
}
|
||
}
|