build(rust): vendor rnix parser crate

third_party/crates/text-size-1.1.1/src/size.rs

@@ -0,0 +1,173 @@
+use {
+    crate::TextLen,
+    std::{
+        convert::TryFrom,
+        fmt, iter,
+        num::TryFromIntError,
+        ops::{Add, AddAssign, Sub, SubAssign},
+        u32,
+    },
+};
+
+/// A measure of text length. Also, equivalently, an index into text.
+///
+/// This is a UTF-8 bytes offset stored as `u32`, but
+/// most clients should treat it as an opaque measure.
+///
+/// For cases that need to escape `TextSize` and return to working directly
+/// with primitive integers, `TextSize` can be converted losslessly to/from
+/// `u32` via [`From`] conversions as well as losslessly be converted [`Into`]
+/// `usize`. The `usize -> TextSize` direction can be done via [`TryFrom`].
+///
+/// These escape hatches are primarily required for unit testing and when
+/// converting from UTF-8 size to another coordinate space, such as UTF-16.
+#[derive(Clone, Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct TextSize {
+    pub(crate) raw: u32,
+}
+
+impl fmt::Debug for TextSize {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.raw)
+    }
+}
+
+impl TextSize {
+    /// Creates a new instance of `TextSize` from a raw `u32`.
+    #[inline]
+    pub const fn new(raw: u32) -> TextSize {
+        TextSize { raw }
+    }
+
+    /// The text size of some primitive text-like object.
+    ///
+    /// Accepts `char`, `&str`, and `&String`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// # use text_size::*;
+    /// let char_size = TextSize::of('🦀');
+    /// assert_eq!(char_size, TextSize::from(4));
+    ///
+    /// let str_size = TextSize::of("rust-analyzer");
+    /// assert_eq!(str_size, TextSize::from(13));
+    /// ```
+    #[inline]
+    pub fn of<T: TextLen>(text: T) -> TextSize {
+        text.text_len()
+    }
+}
+
+/// Methods to act like a primitive integer type, where reasonably applicable.
+//  Last updated for parity with Rust 1.42.0.
+impl TextSize {
+    /// Checked addition. Returns `None` if overflow occurred.
+    #[inline]
+    pub const fn checked_add(self, rhs: TextSize) -> Option<TextSize> {
+        match self.raw.checked_add(rhs.raw) {
+            Some(raw) => Some(TextSize { raw }),
+            None => None,
+        }
+    }
+
+    /// Checked subtraction. Returns `None` if overflow occurred.
+    #[inline]
+    pub const fn checked_sub(self, rhs: TextSize) -> Option<TextSize> {
+        match self.raw.checked_sub(rhs.raw) {
+            Some(raw) => Some(TextSize { raw }),
+            None => None,
+        }
+    }
+}
+
+impl From<u32> for TextSize {
+    #[inline]
+    fn from(raw: u32) -> Self {
+        TextSize { raw }
+    }
+}
+
+impl From<TextSize> for u32 {
+    #[inline]
+    fn from(value: TextSize) -> Self {
+        value.raw
+    }
+}
+
+impl TryFrom<usize> for TextSize {
+    type Error = TryFromIntError;
+    #[inline]
+    fn try_from(value: usize) -> Result<Self, TryFromIntError> {
+        Ok(u32::try_from(value)?.into())
+    }
+}
+
+impl From<TextSize> for usize {
+    #[inline]
+    fn from(value: TextSize) -> Self {
+        value.raw as usize
+    }
+}
+
+macro_rules! ops {
+    (impl $Op:ident for TextSize by fn $f:ident = $op:tt) => {
+        impl $Op<TextSize> for TextSize {
+            type Output = TextSize;
+            #[inline]
+            fn $f(self, other: TextSize) -> TextSize {
+                TextSize { raw: self.raw $op other.raw }
+            }
+        }
+        impl $Op<&TextSize> for TextSize {
+            type Output = TextSize;
+            #[inline]
+            fn $f(self, other: &TextSize) -> TextSize {
+                self $op *other
+            }
+        }
+        impl<T> $Op<T> for &TextSize
+        where
+            TextSize: $Op<T, Output=TextSize>,
+        {
+            type Output = TextSize;
+            #[inline]
+            fn $f(self, other: T) -> TextSize {
+                *self $op other
+            }
+        }
+    };
+}
+
+ops!(impl Add for TextSize by fn add = +);
+ops!(impl Sub for TextSize by fn sub = -);
+
+impl<A> AddAssign<A> for TextSize
+where
+    TextSize: Add<A, Output = TextSize>,
+{
+    #[inline]
+    fn add_assign(&mut self, rhs: A) {
+        *self = *self + rhs
+    }
+}
+
+impl<S> SubAssign<S> for TextSize
+where
+    TextSize: Sub<S, Output = TextSize>,
+{
+    #[inline]
+    fn sub_assign(&mut self, rhs: S) {
+        *self = *self - rhs
+    }
+}
+
+impl<A> iter::Sum<A> for TextSize
+where
+    TextSize: Add<A, Output = TextSize>,
+{
+    #[inline]
+    fn sum<I: Iterator<Item = A>>(iter: I) -> TextSize {
+        iter.fold(0.into(), Add::add)
+    }
+}