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Diffstat (limited to 'vendor/text-size/src/range.rs')
| -rw-r--r-- | vendor/text-size/src/range.rs | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/vendor/text-size/src/range.rs b/vendor/text-size/src/range.rs new file mode 100644 index 000000000..4a98deec5 --- /dev/null +++ b/vendor/text-size/src/range.rs @@ -0,0 +1,456 @@ +use cmp::Ordering; + +use { + crate::TextSize, + std::{ + cmp, fmt, + ops::{Add, AddAssign, Bound, Index, IndexMut, Range, RangeBounds, Sub, SubAssign}, + }, +}; + +/// A range in text, represented as a pair of [`TextSize`][struct@TextSize]. +/// +/// It is a logic error for `start` to be greater than `end`. +#[derive(Default, Copy, Clone, Eq, PartialEq, Hash)] +pub struct TextRange { + // Invariant: start <= end + start: TextSize, + end: TextSize, +} + +impl fmt::Debug for TextRange { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "{}..{}", self.start().raw, self.end().raw) + } +} + +impl TextRange { + /// Creates a new `TextRange` with the given `start` and `end` (`start..end`). + /// + /// # Panics + /// + /// Panics if `end < start`. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let start = TextSize::from(5); + /// let end = TextSize::from(10); + /// let range = TextRange::new(start, end); + /// + /// assert_eq!(range.start(), start); + /// assert_eq!(range.end(), end); + /// assert_eq!(range.len(), end - start); + /// ``` + #[inline] + pub fn new(start: TextSize, end: TextSize) -> TextRange { + assert!(start <= end); + TextRange { start, end } + } + + /// Create a new `TextRange` with the given `offset` and `len` (`offset..offset + len`). + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let text = "0123456789"; + /// + /// let offset = TextSize::from(2); + /// let length = TextSize::from(5); + /// let range = TextRange::at(offset, length); + /// + /// assert_eq!(range, TextRange::new(offset, offset + length)); + /// assert_eq!(&text[range], "23456") + /// ``` + #[inline] + pub fn at(offset: TextSize, len: TextSize) -> TextRange { + TextRange::new(offset, offset + len) + } + + /// Create a zero-length range at the specified offset (`offset..offset`). + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let point: TextSize; + /// # point = TextSize::from(3); + /// let range = TextRange::empty(point); + /// assert!(range.is_empty()); + /// assert_eq!(range, TextRange::new(point, point)); + /// ``` + #[inline] + pub fn empty(offset: TextSize) -> TextRange { + TextRange { + start: offset, + end: offset, + } + } + + /// Create a range up to the given end (`..end`). + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let point: TextSize; + /// # point = TextSize::from(12); + /// let range = TextRange::up_to(point); + /// + /// assert_eq!(range.len(), point); + /// assert_eq!(range, TextRange::new(0.into(), point)); + /// assert_eq!(range, TextRange::at(0.into(), point)); + /// ``` + #[inline] + pub fn up_to(end: TextSize) -> TextRange { + TextRange { + start: 0.into(), + end, + } + } +} + +/// Identity methods. +impl TextRange { + /// The start point of this range. + #[inline] + pub const fn start(self) -> TextSize { + self.start + } + + /// The end point of this range. + #[inline] + pub const fn end(self) -> TextSize { + self.end + } + + /// The size of this range. + #[inline] + pub const fn len(self) -> TextSize { + // HACK for const fn: math on primitives only + TextSize { + raw: self.end().raw - self.start().raw, + } + } + + /// Check if this range is empty. + #[inline] + pub const fn is_empty(self) -> bool { + // HACK for const fn: math on primitives only + self.start().raw == self.end().raw + } +} + +/// Manipulation methods. +impl TextRange { + /// Check if this range contains an offset. + /// + /// The end index is considered excluded. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let (start, end): (TextSize, TextSize); + /// # start = 10.into(); end = 20.into(); + /// let range = TextRange::new(start, end); + /// assert!(range.contains(start)); + /// assert!(!range.contains(end)); + /// ``` + #[inline] + pub fn contains(self, offset: TextSize) -> bool { + self.start() <= offset && offset < self.end() + } + + /// Check if this range contains an offset. + /// + /// The end index is considered included. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let (start, end): (TextSize, TextSize); + /// # start = 10.into(); end = 20.into(); + /// let range = TextRange::new(start, end); + /// assert!(range.contains_inclusive(start)); + /// assert!(range.contains_inclusive(end)); + /// ``` + #[inline] + pub fn contains_inclusive(self, offset: TextSize) -> bool { + self.start() <= offset && offset <= self.end() + } + + /// Check if this range completely contains another range. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// let larger = TextRange::new(0.into(), 20.into()); + /// let smaller = TextRange::new(5.into(), 15.into()); + /// assert!(larger.contains_range(smaller)); + /// assert!(!smaller.contains_range(larger)); + /// + /// // a range always contains itself + /// assert!(larger.contains_range(larger)); + /// assert!(smaller.contains_range(smaller)); + /// ``` + #[inline] + pub fn contains_range(self, other: TextRange) -> bool { + self.start() <= other.start() && other.end() <= self.end() + } + + /// The range covered by both ranges, if it exists. + /// If the ranges touch but do not overlap, the output range is empty. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// assert_eq!( + /// TextRange::intersect( + /// TextRange::new(0.into(), 10.into()), + /// TextRange::new(5.into(), 15.into()), + /// ), + /// Some(TextRange::new(5.into(), 10.into())), + /// ); + /// ``` + #[inline] + pub fn intersect(self, other: TextRange) -> Option<TextRange> { + let start = cmp::max(self.start(), other.start()); + let end = cmp::min(self.end(), other.end()); + if end < start { + return None; + } + Some(TextRange::new(start, end)) + } + + /// Extends the range to cover `other` as well. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// assert_eq!( + /// TextRange::cover( + /// TextRange::new(0.into(), 5.into()), + /// TextRange::new(15.into(), 20.into()), + /// ), + /// TextRange::new(0.into(), 20.into()), + /// ); + /// ``` + #[inline] + pub fn cover(self, other: TextRange) -> TextRange { + let start = cmp::min(self.start(), other.start()); + let end = cmp::max(self.end(), other.end()); + TextRange::new(start, end) + } + + /// Extends the range to cover `other` offsets as well. + /// + /// # Examples + /// + /// ```rust + /// # use text_size::*; + /// assert_eq!( + /// TextRange::empty(0.into()).cover_offset(20.into()), + /// TextRange::new(0.into(), 20.into()), + /// ) + /// ``` + #[inline] + pub fn cover_offset(self, offset: TextSize) -> TextRange { + self.cover(TextRange::empty(offset)) + } + + /// Add an offset to this range. + /// + /// Note that this is not appropriate for changing where a `TextRange` is + /// within some string; rather, it is for changing the reference anchor + /// that the `TextRange` is measured against. + /// + /// The unchecked version (`Add::add`) will _always_ panic on overflow, + /// in contrast to primitive integers, which check in debug mode only. + #[inline] + pub fn checked_add(self, offset: TextSize) -> Option<TextRange> { + Some(TextRange { + start: self.start.checked_add(offset)?, + end: self.end.checked_add(offset)?, + }) + } + + /// Subtract an offset from this range. + /// + /// Note that this is not appropriate for changing where a `TextRange` is + /// within some string; rather, it is for changing the reference anchor + /// that the `TextRange` is measured against. + /// + /// The unchecked version (`Sub::sub`) will _always_ panic on overflow, + /// in contrast to primitive integers, which check in debug mode only. + #[inline] + pub fn checked_sub(self, offset: TextSize) -> Option<TextRange> { + Some(TextRange { + start: self.start.checked_sub(offset)?, + end: self.end.checked_sub(offset)?, + }) + } + + /// Relative order of the two ranges (overlapping ranges are considered + /// equal). + /// + /// + /// This is useful when, for example, binary searching an array of disjoint + /// ranges. + /// + /// # Examples + /// + /// ``` + /// # use text_size::*; + /// # use std::cmp::Ordering; + /// + /// let a = TextRange::new(0.into(), 3.into()); + /// let b = TextRange::new(4.into(), 5.into()); + /// assert_eq!(a.ordering(b), Ordering::Less); + /// + /// let a = TextRange::new(0.into(), 3.into()); + /// let b = TextRange::new(3.into(), 5.into()); + /// assert_eq!(a.ordering(b), Ordering::Less); + /// + /// let a = TextRange::new(0.into(), 3.into()); + /// let b = TextRange::new(2.into(), 5.into()); + /// assert_eq!(a.ordering(b), Ordering::Equal); + /// + /// let a = TextRange::new(0.into(), 3.into()); + /// let b = TextRange::new(2.into(), 2.into()); + /// assert_eq!(a.ordering(b), Ordering::Equal); + /// + /// let a = TextRange::new(2.into(), 3.into()); + /// let b = TextRange::new(2.into(), 2.into()); + /// assert_eq!(a.ordering(b), Ordering::Greater); + /// ``` + #[inline] + pub fn ordering(self, other: TextRange) -> Ordering { + if self.end() <= other.start() { + Ordering::Less + } else if other.end() <= self.start() { + Ordering::Greater + } else { + Ordering::Equal + } + } +} + +impl Index<TextRange> for str { + type Output = str; + #[inline] + fn index(&self, index: TextRange) -> &str { + &self[Range::<usize>::from(index)] + } +} + +impl Index<TextRange> for String { + type Output = str; + #[inline] + fn index(&self, index: TextRange) -> &str { + &self[Range::<usize>::from(index)] + } +} + +impl IndexMut<TextRange> for str { + #[inline] + fn index_mut(&mut self, index: TextRange) -> &mut str { + &mut self[Range::<usize>::from(index)] + } +} + +impl IndexMut<TextRange> for String { + #[inline] + fn index_mut(&mut self, index: TextRange) -> &mut str { + &mut self[Range::<usize>::from(index)] + } +} + +impl RangeBounds<TextSize> for TextRange { + fn start_bound(&self) -> Bound<&TextSize> { + Bound::Included(&self.start) + } + + fn end_bound(&self) -> Bound<&TextSize> { + Bound::Excluded(&self.end) + } +} + +impl<T> From<TextRange> for Range<T> +where + T: From<TextSize>, +{ + #[inline] + fn from(r: TextRange) -> Self { + r.start().into()..r.end().into() + } +} + +macro_rules! ops { + (impl $Op:ident for TextRange by fn $f:ident = $op:tt) => { + impl $Op<&TextSize> for TextRange { + type Output = TextRange; + #[inline] + fn $f(self, other: &TextSize) -> TextRange { + self $op *other + } + } + impl<T> $Op<T> for &TextRange + where + TextRange: $Op<T, Output=TextRange>, + { + type Output = TextRange; + #[inline] + fn $f(self, other: T) -> TextRange { + *self $op other + } + } + }; +} + +impl Add<TextSize> for TextRange { + type Output = TextRange; + #[inline] + fn add(self, offset: TextSize) -> TextRange { + self.checked_add(offset) + .expect("TextRange +offset overflowed") + } +} + +impl Sub<TextSize> for TextRange { + type Output = TextRange; + #[inline] + fn sub(self, offset: TextSize) -> TextRange { + self.checked_sub(offset) + .expect("TextRange -offset overflowed") + } +} + +ops!(impl Add for TextRange by fn add = +); +ops!(impl Sub for TextRange by fn sub = -); + +impl<A> AddAssign<A> for TextRange +where + TextRange: Add<A, Output = TextRange>, +{ + #[inline] + fn add_assign(&mut self, rhs: A) { + *self = *self + rhs + } +} + +impl<S> SubAssign<S> for TextRange +where + TextRange: Sub<S, Output = TextRange>, +{ + #[inline] + fn sub_assign(&mut self, rhs: S) { + *self = *self - rhs + } +} |