vendor/kstring/src/stack.rs - toolchain/rustc - Git at Google

 use std::fmt;

 pub(crate) type Len = u8;

 /// Fixed-size stack-allocated string
 #[derive(Copy, Clone)]
 pub struct StackString<const CAPACITY: usize> {
     len: Len,
     buffer: StrBuffer<CAPACITY>,
 }

 impl<const CAPACITY: usize> StackString<CAPACITY> {
     pub const CAPACITY: usize = CAPACITY;
     pub const EMPTY: Self = Self::empty();

     const fn empty() -> Self {
         Self {
             len: 0,
             buffer: StrBuffer::empty(),
         }
     }

     /// Create a `StackString` from a `&str`, if it'll fit within `Self::CAPACITY`
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let s = kstring::StackString::<3>::try_new("foo");
     /// assert_eq!(s.as_deref(), Some("foo"));
     /// let s = kstring::StackString::<3>::try_new("foobar");
     /// assert_eq!(s, None);
     /// ```
     #[inline]
     #[must_use]
     pub fn try_new(s: &str) -> Option<Self> {
         let len = s.as_bytes().len();
         if len <= Self::CAPACITY {
             #[cfg(feature = "unsafe")]
             let stack = {
                 unsafe {
                     // SAFETY: We've confirmed `len` is within size
                     Self::new_unchecked(s)
                 }
             };
             #[cfg(not(feature = "unsafe"))]
             let stack = { Self::new(s) };
             Some(stack)
         } else {
             None
         }
     }

     /// Create a `StackString` from a `&str`
     ///
     /// # Panic
     ///
     /// Calling this function with a string larger than `Self::CAPACITY` will panic
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let s = kstring::StackString::<3>::new("foo");
     /// assert_eq!(s, "foo");
     /// ```
     #[inline]
     #[must_use]
     pub fn new(s: &str) -> Self {
         let len = s.as_bytes().len() as u8;
         debug_assert!(Self::CAPACITY <= Len::MAX.into());
         let buffer = StrBuffer::new(s);
         Self { len, buffer }
     }

     /// Create a `StackString` from a `&str`
     ///
     /// # Safety
     ///
     /// Calling this function with a string larger than `Self::CAPACITY` is undefined behavior.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let s = unsafe {
     ///     // SAFETY: Literal is short-enough
     ///     kstring::StackString::<3>::new_unchecked("foo")
     /// };
     /// assert_eq!(s, "foo");
     /// ```
     #[inline]
     #[must_use]
     #[cfg(feature = "unsafe")]
     pub unsafe fn new_unchecked(s: &str) -> Self {
         let len = s.as_bytes().len() as u8;
         debug_assert!(Self::CAPACITY <= Len::MAX.into());
         let buffer = StrBuffer::new_unchecked(s);
         Self { len, buffer }
     }

     /// Extracts a string slice containing the entire `StackString`.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let s = kstring::StackString::<3>::try_new("foo").unwrap();
     ///
     /// assert_eq!("foo", s.as_str());
     /// ```
     #[inline]
     #[must_use]
     pub fn as_str(&self) -> &str {
         let len = self.len as usize;
         #[cfg(feature = "unsafe")]
         unsafe {
             // SAFETY: Constructors guarantee that `buffer[..len]` is a `str`,
             // and we don't mutate the data afterwards.
             self.buffer.as_str_unchecked(len)
         }
         #[cfg(not(feature = "unsafe"))]
         self.buffer.as_str(len)
     }

     /// Converts a `StackString` into a mutable string slice.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let mut s = kstring::StackString::<6>::try_new("foobar").unwrap();
     /// let s_mut_str = s.as_mut_str();
     ///
     /// s_mut_str.make_ascii_uppercase();
     ///
     /// assert_eq!("FOOBAR", s_mut_str);
     /// ```
     #[inline]
     #[must_use]
     pub fn as_mut_str(&mut self) -> &mut str {
         let len = self.len as usize;
         #[cfg(feature = "unsafe")]
         unsafe {
             // SAFETY: Constructors guarantee that `buffer[..len]` is a `str`,
             // and we don't mutate the data afterwards.
             self.buffer.as_mut_str_unchecked(len)
         }
         #[cfg(not(feature = "unsafe"))]
         self.buffer.as_mut_str(len)
     }

     /// Returns the length of this `StasckString`, in bytes, not [`char`]s or
     /// graphemes. In other words, it might not be what a human considers the
     /// length of the string.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let a = kstring::StackString::<3>::try_new("foo").unwrap();
     /// assert_eq!(a.len(), 3);
     ///
     /// let fancy_f = kstring::StackString::<4>::try_new("ƒoo").unwrap();
     /// assert_eq!(fancy_f.len(), 4);
     /// assert_eq!(fancy_f.chars().count(), 3);
     /// ```
     #[inline]
     #[must_use]
     pub fn len(&self) -> usize {
         self.len as usize
     }

     /// Returns `true` if this `StackString` has a length of zero, and `false` otherwise.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let mut v = kstring::StackString::<20>::EMPTY;
     /// assert!(v.is_empty());
     ///
     /// let a = kstring::StackString::<3>::try_new("foo").unwrap();
     /// assert!(!a.is_empty());
     /// ```
     #[inline]
     #[must_use]
     pub fn is_empty(&self) -> bool {
         self.len() == 0
     }

     /// Truncates this `StackString`, removing all contents.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let mut s = kstring::StackString::<3>::try_new("foo").unwrap();
     ///
     /// s.clear();
     ///
     /// assert!(s.is_empty());
     /// assert_eq!(0, s.len());
     /// ```
     #[inline]
     pub fn clear(&mut self) {
         self.len = 0;
     }

     /// Shortens this `StackString` to the specified length.
     ///
     /// If `new_len` is greater than the string's current length, this has no
     /// effect.
     ///
     /// Note that this method has no effect on the allocated capacity
     /// of the string
     ///
     /// # Panics
     ///
     /// Panics if `new_len` does not lie on a [`char`] boundary.
     ///
     /// # Examples
     ///
     /// Basic usage:
     ///
     /// ```
     /// let mut s = kstring::StackString::<5>::try_new("hello").unwrap();
     ///
     /// s.truncate(2);
     ///
     /// assert_eq!(s, "he");
     /// ```
     #[inline]
     pub fn truncate(&mut self, new_len: usize) {
         if new_len <= self.len() {
             assert!(self.is_char_boundary(new_len));
             self.len = new_len as u8;
         }
     }
 }

 impl<const CAPACITY: usize> Default for StackString<CAPACITY> {
     fn default() -> Self {
         Self::empty()
     }
 }

 impl<const CAPACITY: usize> std::ops::Deref for StackString<CAPACITY> {
     type Target = str;

     #[inline]
     fn deref(&self) -> &str {
         self.as_str()
     }
 }

 impl<const CAPACITY: usize> Eq for StackString<CAPACITY> {}

 impl<const C1: usize, const C2: usize> PartialEq<StackString<C1>> for StackString<C2> {
     #[inline]
     fn eq(&self, other: &StackString<C1>) -> bool {
         PartialEq::eq(self.as_str(), other.as_str())
     }
 }

 impl<const CAPACITY: usize> PartialEq<str> for StackString<CAPACITY> {
     #[inline]
     fn eq(&self, other: &str) -> bool {
         PartialEq::eq(self.as_str(), other)
     }
 }

 impl<'s, const CAPACITY: usize> PartialEq<&'s str> for StackString<CAPACITY> {
     #[inline]
     fn eq(&self, other: &&str) -> bool {
         PartialEq::eq(self.as_str(), *other)
     }
 }

 impl<const CAPACITY: usize> PartialEq<String> for StackString<CAPACITY> {
     #[inline]
     fn eq(&self, other: &String) -> bool {
         PartialEq::eq(self.as_str(), other.as_str())
     }
 }

 impl<const CAPACITY: usize> Ord for StackString<CAPACITY> {
     #[inline]
     fn cmp(&self, other: &Self) -> std::cmp::Ordering {
         self.as_str().cmp(other.as_str())
     }
 }

 impl<const C1: usize, const C2: usize> PartialOrd<StackString<C1>> for StackString<C2> {
     #[inline]
     fn partial_cmp(&self, other: &StackString<C1>) -> Option<std::cmp::Ordering> {
         self.as_str().partial_cmp(other.as_str())
     }
 }

 impl<const CAPACITY: usize> PartialOrd<str> for StackString<CAPACITY> {
     #[inline]
     fn partial_cmp(&self, other: &str) -> Option<std::cmp::Ordering> {
         self.as_str().partial_cmp(other)
     }
 }

 impl<'s, const CAPACITY: usize> PartialOrd<&'s str> for StackString<CAPACITY> {
     #[inline]
     fn partial_cmp(&self, other: &&str) -> Option<std::cmp::Ordering> {
         self.as_str().partial_cmp(other)
     }
 }

 impl<const CAPACITY: usize> PartialOrd<String> for StackString<CAPACITY> {
     #[inline]
     fn partial_cmp(&self, other: &String) -> Option<std::cmp::Ordering> {
         self.as_str().partial_cmp(other.as_str())
     }
 }

 impl<const CAPACITY: usize> std::hash::Hash for StackString<CAPACITY> {
     #[inline]
     fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
         self.as_str().hash(state);
     }
 }

 impl<const CAPACITY: usize> fmt::Debug for StackString<CAPACITY> {
     #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt::Debug::fmt(self.as_str(), f)
     }
 }

 impl<const CAPACITY: usize> fmt::Display for StackString<CAPACITY> {
     #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt::Display::fmt(self.as_str(), f)
     }
 }

 impl<const CAPACITY: usize> AsRef<str> for StackString<CAPACITY> {
     #[inline]
     fn as_ref(&self) -> &str {
         self.as_str()
     }
 }

 impl<const CAPACITY: usize> AsRef<[u8]> for StackString<CAPACITY> {
     #[inline]
     fn as_ref(&self) -> &[u8] {
         self.as_bytes()
     }
 }

 impl<const CAPACITY: usize> AsRef<std::ffi::OsStr> for StackString<CAPACITY> {
     #[inline]
     fn as_ref(&self) -> &std::ffi::OsStr {
         (&**self).as_ref()
     }
 }

 impl<const CAPACITY: usize> AsRef<std::path::Path> for StackString<CAPACITY> {
     #[inline]
     fn as_ref(&self) -> &std::path::Path {
         std::path::Path::new(self)
     }
 }

 impl<const CAPACITY: usize> std::borrow::Borrow<str> for StackString<CAPACITY> {
     #[inline]
     fn borrow(&self) -> &str {
         self.as_str()
     }
 }

 #[derive(Copy, Clone)]
 #[repr(transparent)]
 pub(crate) struct StrBuffer<const CAPACITY: usize>([u8; CAPACITY]);

 impl<const CAPACITY: usize> StrBuffer<CAPACITY> {
     pub(crate) const fn empty() -> Self {
         let array = [0; CAPACITY];
         StrBuffer(array)
     }

     #[inline]
     pub(crate) fn new(s: &str) -> Self {
         let len = s.as_bytes().len();
         debug_assert!(len <= CAPACITY);
         let mut buffer = Self::default();
         if let Some(buffer) = buffer.0.get_mut(..len) {
             buffer.copy_from_slice(s.as_bytes());
         } else {
             panic!("`{}` is larger than capacity {}", s, CAPACITY);
         }
         buffer
     }

     #[inline]
     #[cfg(not(feature = "unsafe"))]
     pub(crate) fn as_str(&self, len: usize) -> &str {
         let slice = self.0.get(..len).unwrap();
         std::str::from_utf8(slice).unwrap()
     }

     #[inline]
     #[cfg(not(feature = "unsafe"))]
     pub(crate) fn as_mut_str(&mut self, len: usize) -> &mut str {
         let slice = self.0.get_mut(..len).unwrap();
         std::str::from_utf8_mut(slice).unwrap()
     }
 }

 impl<const CAPACITY: usize> StrBuffer<CAPACITY> {
     #[inline]
     #[cfg(feature = "unsafe")]
     pub(crate) unsafe fn new_unchecked(s: &str) -> Self {
         let len = s.as_bytes().len();
         debug_assert!(len <= CAPACITY);
         let mut buffer = Self::default();
         buffer
             .0
             .get_unchecked_mut(..len)
             .copy_from_slice(s.as_bytes());
         buffer
     }

     #[inline]
     #[cfg(feature = "unsafe")]
     pub(crate) unsafe fn as_str_unchecked(&self, len: usize) -> &str {
         let slice = self.0.get_unchecked(..len);
         std::str::from_utf8_unchecked(slice)
     }

     #[inline]
     #[cfg(feature = "unsafe")]
     pub(crate) unsafe fn as_mut_str_unchecked(&mut self, len: usize) -> &mut str {
         let slice = self.0.get_unchecked_mut(..len);
         std::str::from_utf8_unchecked_mut(slice)
     }
 }

 impl<const CAPACITY: usize> Default for StrBuffer<CAPACITY> {
     fn default() -> Self {
         Self::empty()
     }
 }
	use std::fmt;

	pub(crate) type Len = u8;

	/// Fixed-size stack-allocated string
	#[derive(Copy, Clone)]
	pub struct StackString<const CAPACITY: usize> {
	len: Len,
	buffer: StrBuffer<CAPACITY>,
	}

	impl<const CAPACITY: usize> StackString<CAPACITY> {
	pub const CAPACITY: usize = CAPACITY;
	pub const EMPTY: Self = Self::empty();

	const fn empty() -> Self {
	Self {
	len: 0,
	buffer: StrBuffer::empty(),
	}
	}

	/// Create a `StackString` from a `&str`, if it'll fit within `Self::CAPACITY`
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let s = kstring::StackString::<3>::try_new("foo");
	/// assert_eq!(s.as_deref(), Some("foo"));
	/// let s = kstring::StackString::<3>::try_new("foobar");
	/// assert_eq!(s, None);
	/// ```
	#[inline]
	#[must_use]
	pub fn try_new(s: &str) -> Option<Self> {
	let len = s.as_bytes().len();
	if len <= Self::CAPACITY {
	#[cfg(feature = "unsafe")]
	let stack = {
	unsafe {
	// SAFETY: We've confirmed `len` is within size
	Self::new_unchecked(s)
	}
	};
	#[cfg(not(feature = "unsafe"))]
	let stack = { Self::new(s) };
	Some(stack)
	} else {
	None
	}
	}

	/// Create a `StackString` from a `&str`
	///
	/// # Panic
	///
	/// Calling this function with a string larger than `Self::CAPACITY` will panic
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let s = kstring::StackString::<3>::new("foo");
	/// assert_eq!(s, "foo");
	/// ```
	#[inline]
	#[must_use]
	pub fn new(s: &str) -> Self {
	let len = s.as_bytes().len() as u8;
	debug_assert!(Self::CAPACITY <= Len::MAX.into());
	let buffer = StrBuffer::new(s);
	Self { len, buffer }
	}

	/// Create a `StackString` from a `&str`
	///
	/// # Safety
	///
	/// Calling this function with a string larger than `Self::CAPACITY` is undefined behavior.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let s = unsafe {
	/// // SAFETY: Literal is short-enough
	/// kstring::StackString::<3>::new_unchecked("foo")
	/// };
	/// assert_eq!(s, "foo");
	/// ```
	#[inline]
	#[must_use]
	#[cfg(feature = "unsafe")]
	pub unsafe fn new_unchecked(s: &str) -> Self {
	let len = s.as_bytes().len() as u8;
	debug_assert!(Self::CAPACITY <= Len::MAX.into());
	let buffer = StrBuffer::new_unchecked(s);
	Self { len, buffer }
	}

	/// Extracts a string slice containing the entire `StackString`.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let s = kstring::StackString::<3>::try_new("foo").unwrap();
	///
	/// assert_eq!("foo", s.as_str());
	/// ```
	#[inline]
	#[must_use]
	pub fn as_str(&self) -> &str {
	let len = self.len as usize;
	#[cfg(feature = "unsafe")]
	unsafe {
	// SAFETY: Constructors guarantee that `buffer[..len]` is a `str`,
	// and we don't mutate the data afterwards.
	self.buffer.as_str_unchecked(len)
	}
	#[cfg(not(feature = "unsafe"))]
	self.buffer.as_str(len)
	}

	/// Converts a `StackString` into a mutable string slice.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let mut s = kstring::StackString::<6>::try_new("foobar").unwrap();
	/// let s_mut_str = s.as_mut_str();
	///
	/// s_mut_str.make_ascii_uppercase();
	///
	/// assert_eq!("FOOBAR", s_mut_str);
	/// ```
	#[inline]
	#[must_use]
	pub fn as_mut_str(&mut self) -> &mut str {
	let len = self.len as usize;
	#[cfg(feature = "unsafe")]
	unsafe {
	// SAFETY: Constructors guarantee that `buffer[..len]` is a `str`,
	// and we don't mutate the data afterwards.
	self.buffer.as_mut_str_unchecked(len)
	}
	#[cfg(not(feature = "unsafe"))]
	self.buffer.as_mut_str(len)
	}

	/// Returns the length of this `StasckString`, in bytes, not [`char`]s or
	/// graphemes. In other words, it might not be what a human considers the
	/// length of the string.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let a = kstring::StackString::<3>::try_new("foo").unwrap();
	/// assert_eq!(a.len(), 3);
	///
	/// let fancy_f = kstring::StackString::<4>::try_new("ƒoo").unwrap();
	/// assert_eq!(fancy_f.len(), 4);
	/// assert_eq!(fancy_f.chars().count(), 3);
	/// ```
	#[inline]
	#[must_use]
	pub fn len(&self) -> usize {
	self.len as usize
	}

	/// Returns `true` if this `StackString` has a length of zero, and `false` otherwise.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let mut v = kstring::StackString::<20>::EMPTY;
	/// assert!(v.is_empty());
	///
	/// let a = kstring::StackString::<3>::try_new("foo").unwrap();
	/// assert!(!a.is_empty());
	/// ```
	#[inline]
	#[must_use]
	pub fn is_empty(&self) -> bool {
	self.len() == 0
	}

	/// Truncates this `StackString`, removing all contents.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let mut s = kstring::StackString::<3>::try_new("foo").unwrap();
	///
	/// s.clear();
	///
	/// assert!(s.is_empty());
	/// assert_eq!(0, s.len());
	/// ```
	#[inline]
	pub fn clear(&mut self) {
	self.len = 0;
	}

	/// Shortens this `StackString` to the specified length.
	///
	/// If `new_len` is greater than the string's current length, this has no
	/// effect.
	///
	/// Note that this method has no effect on the allocated capacity
	/// of the string
	///
	/// # Panics
	///
	/// Panics if `new_len` does not lie on a [`char`] boundary.
	///
	/// # Examples
	///
	/// Basic usage:
	///
	/// ```
	/// let mut s = kstring::StackString::<5>::try_new("hello").unwrap();
	///
	/// s.truncate(2);
	///
	/// assert_eq!(s, "he");
	/// ```
	#[inline]
	pub fn truncate(&mut self, new_len: usize) {
	if new_len <= self.len() {
	assert!(self.is_char_boundary(new_len));
	self.len = new_len as u8;
	}
	}
	}

	impl<const CAPACITY: usize> Default for StackString<CAPACITY> {
	fn default() -> Self {
	Self::empty()
	}
	}

	impl<const CAPACITY: usize> std::ops::Deref for StackString<CAPACITY> {
	type Target = str;

	#[inline]
	fn deref(&self) -> &str {
	self.as_str()
	}
	}

	impl<const CAPACITY: usize> Eq for StackString<CAPACITY> {}

	impl<const C1: usize, const C2: usize> PartialEq<StackString<C1>> for StackString<C2> {
	#[inline]
	fn eq(&self, other: &StackString<C1>) -> bool {
	PartialEq::eq(self.as_str(), other.as_str())
	}
	}

	impl<const CAPACITY: usize> PartialEq<str> for StackString<CAPACITY> {
	#[inline]
	fn eq(&self, other: &str) -> bool {
	PartialEq::eq(self.as_str(), other)
	}
	}

	impl<'s, const CAPACITY: usize> PartialEq<&'s str> for StackString<CAPACITY> {
	#[inline]
	fn eq(&self, other: &&str) -> bool {
	PartialEq::eq(self.as_str(), *other)
	}
	}

	impl<const CAPACITY: usize> PartialEq<String> for StackString<CAPACITY> {
	#[inline]
	fn eq(&self, other: &String) -> bool {
	PartialEq::eq(self.as_str(), other.as_str())
	}
	}

	impl<const CAPACITY: usize> Ord for StackString<CAPACITY> {
	#[inline]
	fn cmp(&self, other: &Self) -> std::cmp::Ordering {
	self.as_str().cmp(other.as_str())
	}
	}

	impl<const C1: usize, const C2: usize> PartialOrd<StackString<C1>> for StackString<C2> {
	#[inline]
	fn partial_cmp(&self, other: &StackString<C1>) -> Option<std::cmp::Ordering> {
	self.as_str().partial_cmp(other.as_str())
	}
	}

	impl<const CAPACITY: usize> PartialOrd<str> for StackString<CAPACITY> {
	#[inline]
	fn partial_cmp(&self, other: &str) -> Option<std::cmp::Ordering> {
	self.as_str().partial_cmp(other)
	}
	}

	impl<'s, const CAPACITY: usize> PartialOrd<&'s str> for StackString<CAPACITY> {
	#[inline]
	fn partial_cmp(&self, other: &&str) -> Option<std::cmp::Ordering> {
	self.as_str().partial_cmp(other)
	}
	}

	impl<const CAPACITY: usize> PartialOrd<String> for StackString<CAPACITY> {
	#[inline]
	fn partial_cmp(&self, other: &String) -> Option<std::cmp::Ordering> {
	self.as_str().partial_cmp(other.as_str())
	}
	}

	impl<const CAPACITY: usize> std::hash::Hash for StackString<CAPACITY> {
	#[inline]
	fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
	self.as_str().hash(state);
	}
	}

	impl<const CAPACITY: usize> fmt::Debug for StackString<CAPACITY> {
	#[inline]
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	fmt::Debug::fmt(self.as_str(), f)
	}
	}

	impl<const CAPACITY: usize> fmt::Display for StackString<CAPACITY> {
	#[inline]
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	fmt::Display::fmt(self.as_str(), f)
	}
	}

	impl<const CAPACITY: usize> AsRef<str> for StackString<CAPACITY> {
	#[inline]
	fn as_ref(&self) -> &str {
	self.as_str()
	}
	}

	impl<const CAPACITY: usize> AsRef<[u8]> for StackString<CAPACITY> {
	#[inline]
	fn as_ref(&self) -> &[u8] {
	self.as_bytes()
	}
	}

	impl<const CAPACITY: usize> AsRef<std::ffi::OsStr> for StackString<CAPACITY> {
	#[inline]
	fn as_ref(&self) -> &std::ffi::OsStr {
	(&**self).as_ref()
	}
	}

	impl<const CAPACITY: usize> AsRef<std::path::Path> for StackString<CAPACITY> {
	#[inline]
	fn as_ref(&self) -> &std::path::Path {
	std::path::Path::new(self)
	}
	}

	impl<const CAPACITY: usize> std::borrow::Borrow<str> for StackString<CAPACITY> {
	#[inline]
	fn borrow(&self) -> &str {
	self.as_str()
	}
	}

	#[derive(Copy, Clone)]
	#[repr(transparent)]
	pub(crate) struct StrBuffer<const CAPACITY: usize>([u8; CAPACITY]);

	impl<const CAPACITY: usize> StrBuffer<CAPACITY> {
	pub(crate) const fn empty() -> Self {
	let array = [0; CAPACITY];
	StrBuffer(array)
	}

	#[inline]
	pub(crate) fn new(s: &str) -> Self {
	let len = s.as_bytes().len();
	debug_assert!(len <= CAPACITY);
	let mut buffer = Self::default();
	if let Some(buffer) = buffer.0.get_mut(..len) {
	buffer.copy_from_slice(s.as_bytes());
	} else {
	panic!("`{}` is larger than capacity {}", s, CAPACITY);
	}
	buffer
	}

	#[inline]
	#[cfg(not(feature = "unsafe"))]
	pub(crate) fn as_str(&self, len: usize) -> &str {
	let slice = self.0.get(..len).unwrap();
	std::str::from_utf8(slice).unwrap()
	}

	#[inline]
	#[cfg(not(feature = "unsafe"))]
	pub(crate) fn as_mut_str(&mut self, len: usize) -> &mut str {
	let slice = self.0.get_mut(..len).unwrap();
	std::str::from_utf8_mut(slice).unwrap()
	}
	}

	impl<const CAPACITY: usize> StrBuffer<CAPACITY> {
	#[inline]
	#[cfg(feature = "unsafe")]
	pub(crate) unsafe fn new_unchecked(s: &str) -> Self {
	let len = s.as_bytes().len();
	debug_assert!(len <= CAPACITY);
	let mut buffer = Self::default();
	buffer
	.0
	.get_unchecked_mut(..len)
	.copy_from_slice(s.as_bytes());
	buffer
	}

	#[inline]
	#[cfg(feature = "unsafe")]
	pub(crate) unsafe fn as_str_unchecked(&self, len: usize) -> &str {
	let slice = self.0.get_unchecked(..len);
	std::str::from_utf8_unchecked(slice)
	}

	#[inline]
	#[cfg(feature = "unsafe")]
	pub(crate) unsafe fn as_mut_str_unchecked(&mut self, len: usize) -> &mut str {
	let slice = self.0.get_unchecked_mut(..len);
	std::str::from_utf8_unchecked_mut(slice)
	}
	}

	impl<const CAPACITY: usize> Default for StrBuffer<CAPACITY> {
	fn default() -> Self {
	Self::empty()
	}
	}