diff options
| author | mo khan <mo@mokhan.ca> | 2025-07-02 18:36:06 -0600 |
|---|---|---|
| committer | mo khan <mo@mokhan.ca> | 2025-07-02 18:36:06 -0600 |
| commit | 8cdfa445d6629ffef4cb84967ff7017654045bc2 (patch) | |
| tree | 22f0b0907c024c78d26a731e2e1f5219407d8102 /vendor/beef/src | |
| parent | 4351c74c7c5f97156bc94d3a8549b9940ac80e3f (diff) | |
chore: add vendor directory
Diffstat (limited to 'vendor/beef/src')
| -rw-r--r-- | vendor/beef/src/generic.rs | 553 | ||||
| -rw-r--r-- | vendor/beef/src/lean.rs | 69 | ||||
| -rw-r--r-- | vendor/beef/src/lib.rs | 285 | ||||
| -rw-r--r-- | vendor/beef/src/serde.rs | 149 | ||||
| -rw-r--r-- | vendor/beef/src/traits.rs | 175 | ||||
| -rw-r--r-- | vendor/beef/src/wide.rs | 42 |
6 files changed, 1273 insertions, 0 deletions
diff --git a/vendor/beef/src/generic.rs b/vendor/beef/src/generic.rs new file mode 100644 index 00000000..1d7fa2da --- /dev/null +++ b/vendor/beef/src/generic.rs @@ -0,0 +1,553 @@ +//! This module contains the actual, albeit generic, implementaiton of the `Cow`, +//! and the traits that are available to it. + +use alloc::borrow::{Borrow, Cow as StdCow}; +use alloc::string::String; +use alloc::vec::Vec; +use core::cmp::Ordering; +use core::fmt; +use core::hash::{Hash, Hasher}; +use core::marker::PhantomData; +use core::mem::ManuallyDrop; +use core::ptr::NonNull; + +#[cfg(target_pointer_width = "64")] +use crate::lean::internal::Lean; +use crate::traits::{Beef, Capacity}; +use crate::wide::internal::Wide; + +/// A clone-on-write smart pointer, mostly compatible with [`std::borrow::Cow`](https://doc.rust-lang.org/std/borrow/enum.Cow.html). +/// +/// This type is using a generic `U: Capacity`. Use either [`beef::Cow`](../type.Cow.html) or [`beef::lean::Cow`](../lean/type.Cow.html) in your code. +pub struct Cow<'a, T: Beef + ?Sized + 'a, U: Capacity> { + /// Pointer to data + ptr: NonNull<T::PointerT>, + + /// This usize contains length, but it may contain other + /// information pending on impl of `Capacity`, and must therefore + /// always go through `U::len` or `U::unpack` + fat: usize, + + /// Capacity field. For `beef::lean::Cow` this is 0-sized! + cap: U::Field, + + /// Lifetime marker + marker: PhantomData<&'a T>, +} + +impl<T, U> Cow<'_, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + /// Owned data. + /// + /// # Example + /// + /// ```rust + /// use beef::Cow; + /// + /// let owned: Cow<str> = Cow::owned("I own my content".to_string()); + /// ``` + #[inline] + pub fn owned(val: T::Owned) -> Self { + let (ptr, fat, cap) = T::owned_into_parts::<U>(val); + + Cow { + ptr, + fat, + cap, + marker: PhantomData, + } + } +} + +impl<'a, T, U> Cow<'a, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + /// Borrowed data. + /// + /// # Example + /// + /// ```rust + /// use beef::Cow; + /// + /// let borrowed: Cow<str> = Cow::borrowed("I'm just a borrow"); + /// ``` + #[inline] + pub fn borrowed(val: &'a T) -> Self { + let (ptr, fat, cap) = T::ref_into_parts::<U>(val); + + Cow { + ptr, + fat, + cap, + marker: PhantomData, + } + } + + /// Extracts the owned data. + /// + /// Clones the data if it is not already owned. + #[inline] + pub fn into_owned(self) -> T::Owned { + let cow = ManuallyDrop::new(self); + + match cow.capacity() { + Some(capacity) => unsafe { T::owned_from_parts::<U>(cow.ptr, cow.fat, capacity) }, + None => unsafe { &*T::ref_from_parts::<U>(cow.ptr, cow.fat) }.to_owned(), + } + } + + /// Extracts borrowed data. + /// + /// Panics: If the data is owned. + #[inline] + pub fn unwrap_borrowed(self) -> &'a T { + if self.capacity().is_some() { + panic!("Can not turn owned beef::Cow into a borrowed value") + } + unsafe { &*T::ref_from_parts::<U>(self.ptr, self.fat) } + } + + /// Returns `true` if data is borrowed or had no capacity. + /// + /// # Example + /// + /// ```rust + /// use beef::Cow; + /// + /// let borrowed: Cow<str> = Cow::borrowed("Borrowed"); + /// let no_capacity: Cow<str> = Cow::owned(String::new()); + /// let owned: Cow<str> = Cow::owned(String::from("Owned")); + /// + /// assert_eq!(borrowed.is_borrowed(), true); + /// assert_eq!(no_capacity.is_borrowed(), true); + /// assert_eq!(owned.is_borrowed(), false); + /// ``` + #[inline] + pub fn is_borrowed(&self) -> bool { + self.capacity().is_none() + } + + /// Returns `true` if data is owned and has non-0 capacity. + /// + /// # Example + /// + /// ```rust + /// use beef::Cow; + /// + /// let borrowed: Cow<str> = Cow::borrowed("Borrowed"); + /// let no_capacity: Cow<str> = Cow::owned(String::new()); + /// let owned: Cow<str> = Cow::owned(String::from("Owned")); + /// + /// assert_eq!(borrowed.is_owned(), false); + /// assert_eq!(no_capacity.is_owned(), false); + /// assert_eq!(owned.is_owned(), true); + /// ``` + #[inline] + pub fn is_owned(&self) -> bool { + self.capacity().is_some() + } + + /// Internal convenience method for casting `ptr` into a `&T` + #[inline] + fn borrow(&self) -> &T { + unsafe { &*T::ref_from_parts::<U>(self.ptr, self.fat) } + } + + #[inline] + fn capacity(&self) -> Option<U::NonZero> { + U::maybe(self.fat, self.cap) + } +} + +impl<'a> Cow<'a, str, Wide> { + /// Borrowed data. + /// + /// This is functionally identical to [`borrow`](./generic/struct.Cow.html#method.borrow). + /// We use impl specialization to allow this function to be `const`. + /// + /// # Example + /// + /// ```rust + /// use beef::Cow; + /// + /// const HELLO: Cow<str> = Cow::const_str("Hello"); + /// ``` + pub const fn const_str(val: &'a str) -> Self { + Cow { + // We are casting *const T to *mut T, however for all borrowed values + // this raw pointer is only ever dereferenced back to &T. + ptr: unsafe { NonNull::new_unchecked(val.as_ptr() as *mut u8) }, + fat: val.len(), + cap: None, + marker: PhantomData, + } + } +} + +#[cfg(target_pointer_width = "64")] +impl<'a> Cow<'a, str, Lean> { + /// Borrowed data. + /// + /// This is functionally identical to [`borrow`](./generic/struct.Cow.html#method.borrow). + /// We use impl specialization to allow this function to be `const`. + /// + /// # Example + /// + /// ```rust + /// use beef::lean::Cow; + /// + /// const HELLO: Cow<str> = Cow::const_str("Hello"); + /// ``` + pub const fn const_str(val: &'a str) -> Self { + Cow { + // We are casting *const T to *mut T, however for all borrowed values + // this raw pointer is only ever dereferenced back to &T. + ptr: unsafe { NonNull::new_unchecked(val.as_ptr() as *mut u8) }, + fat: Lean::mask_len(val.len()), + cap: Lean, + marker: PhantomData, + } + } +} + +// This requires nightly: +// https://github.com/rust-lang/rust/issues/57563 +#[cfg(feature = "const_fn")] +impl<'a, T> Cow<'a, [T], Wide> +where + T: Clone, +{ + /// Borrowed data. + /// + /// This is functionally identical to [`borrow`](./generic/struct.Cow.html#method.borrow). + /// We use impl specialization to allow this function to be `const`. + /// + /// # Example + /// + /// ```rust + /// use beef::Cow; + /// + /// const HELLO: Cow<[u8]> = Cow::const_slice(&[1, 2, 3]); + /// ``` + pub const fn const_slice(val: &'a [T]) -> Self { + Cow { + // We are casting *const T to *mut T, however for all borrowed values + // this raw pointer is only ever dereferenced back to &T. + ptr: unsafe { NonNull::new_unchecked(val.as_ptr() as *mut T) }, + fat: val.len(), + cap: None, + marker: PhantomData, + } + } +} + +// This requires nightly: +// https://github.com/rust-lang/rust/issues/57563 +#[cfg(all(feature = "const_fn", target_pointer_width = "64"))] +impl<'a, T> Cow<'a, [T], Lean> +where + T: Clone, +{ + /// Borrowed data. + /// + /// This i functionally identical to [`borrow`](./generic/struct.Cow.html#method.borrow). + /// We use impl specialization to allow this function to be `const`. + /// + /// # Example + /// + /// ```rust + /// use beef::lean::Cow; + /// + /// const HELLO: Cow<[u8]> = Cow::const_slice(&[1, 2, 3]); + /// ``` + pub const fn const_slice(val: &'a [T]) -> Self { + Cow { + // We are casting *const T to *mut T, however for all borrowed values + // this raw pointer is only ever dereferenced back to &T. + ptr: unsafe { NonNull::new_unchecked(val.as_ptr() as *mut T) }, + fat: Lean::mask_len(val.len()), + cap: Lean, + marker: PhantomData, + } + } +} + +impl<T, U> Hash for Cow<'_, T, U> +where + T: Hash + Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn hash<H: Hasher>(&self, state: &mut H) { + self.borrow().hash(state) + } +} + +impl<'a, T, U> Default for Cow<'a, T, U> +where + T: Beef + ?Sized, + U: Capacity, + &'a T: Default, +{ + #[inline] + fn default() -> Self { + Cow::borrowed(Default::default()) + } +} + +impl<T, U> Eq for Cow<'_, T, U> +where + T: Eq + Beef + ?Sized, + U: Capacity, +{ +} + +impl<A, B, U, V> PartialOrd<Cow<'_, B, V>> for Cow<'_, A, U> +where + A: Beef + ?Sized + PartialOrd<B>, + B: Beef + ?Sized, + U: Capacity, + V: Capacity, +{ + #[inline] + fn partial_cmp(&self, other: &Cow<'_, B, V>) -> Option<Ordering> { + PartialOrd::partial_cmp(self.borrow(), other.borrow()) + } +} + +impl<T, U> Ord for Cow<'_, T, U> +where + T: Ord + Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn cmp(&self, other: &Self) -> Ordering { + Ord::cmp(self.borrow(), other.borrow()) + } +} + +impl<'a, T, U> From<&'a T> for Cow<'a, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn from(val: &'a T) -> Self { + Cow::borrowed(val) + } +} + +impl<U> From<String> for Cow<'_, str, U> +where + U: Capacity, +{ + #[inline] + fn from(s: String) -> Self { + Cow::owned(s) + } +} + +impl<T, U> From<Vec<T>> for Cow<'_, [T], U> +where + T: Clone, + U: Capacity, +{ + #[inline] + fn from(v: Vec<T>) -> Self { + Cow::owned(v) + } +} + +impl<T, U> Drop for Cow<'_, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn drop(&mut self) { + if let Some(capacity) = self.capacity() { + unsafe { T::owned_from_parts::<U>(self.ptr, self.fat, capacity) }; + } + } +} + +impl<'a, T, U> Clone for Cow<'a, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn clone(&self) -> Self { + match self.capacity() { + Some(_) => Cow::owned(self.borrow().to_owned()), + None => Cow { ..*self }, + } + } +} + +impl<T, U> core::ops::Deref for Cow<'_, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + type Target = T; + + #[inline] + fn deref(&self) -> &T { + self.borrow() + } +} + +impl<T, U> AsRef<T> for Cow<'_, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn as_ref(&self) -> &T { + self.borrow() + } +} + +impl<T, U> Borrow<T> for Cow<'_, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn borrow(&self) -> &T { + self.borrow() + } +} + +impl<'a, T, U> From<StdCow<'a, T>> for Cow<'a, T, U> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn from(stdcow: StdCow<'a, T>) -> Self { + match stdcow { + StdCow::Borrowed(v) => Self::borrowed(v), + StdCow::Owned(v) => Self::owned(v), + } + } +} + +impl<'a, T, U> From<Cow<'a, T, U>> for StdCow<'a, T> +where + T: Beef + ?Sized, + U: Capacity, +{ + #[inline] + fn from(cow: Cow<'a, T, U>) -> Self { + let cow = ManuallyDrop::new(cow); + + match cow.capacity() { + Some(capacity) => { + StdCow::Owned(unsafe { T::owned_from_parts::<U>(cow.ptr, cow.fat, capacity) }) + } + None => StdCow::Borrowed(unsafe { &*T::ref_from_parts::<U>(cow.ptr, cow.fat) }), + } + } +} + +impl<A, B, U, V> PartialEq<Cow<'_, B, V>> for Cow<'_, A, U> +where + A: Beef + ?Sized, + B: Beef + ?Sized, + U: Capacity, + V: Capacity, + A: PartialEq<B>, +{ + fn eq(&self, other: &Cow<B, V>) -> bool { + self.borrow() == other.borrow() + } +} + +macro_rules! impl_eq { + ($($(@for< $bounds:tt >)? $ptr:ty => $([$($deref:tt)+])? <$with:ty>,)*) => {$( + impl<U $(, $bounds)*> PartialEq<$with> for Cow<'_, $ptr, U> + where + U: Capacity, + $( $bounds: Clone + PartialEq, )* + { + #[inline] + fn eq(&self, other: &$with) -> bool { + self.borrow() == $($($deref)*)* other + } + } + + impl<U $(, $bounds)*> PartialEq<Cow<'_, $ptr, U>> for $with + where + U: Capacity, + $( $bounds: Clone + PartialEq, )* + { + #[inline] + fn eq(&self, other: &Cow<$ptr, U>) -> bool { + $($($deref)*)* self == other.borrow() + } + } + )*}; +} + +impl_eq! { + str => <str>, + str => [*]<&str>, + str => <String>, + @for<T> [T] => <[T]>, + @for<T> [T] => [*]<&[T]>, + @for<T> [T] => [&**]<Vec<T>>, +} + +impl<T, U> fmt::Debug for Cow<'_, T, U> +where + T: Beef + fmt::Debug + ?Sized, + U: Capacity, +{ + #[inline] + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + self.borrow().fmt(f) + } +} + +impl<T, U> fmt::Display for Cow<'_, T, U> +where + T: Beef + fmt::Display + ?Sized, + U: Capacity, +{ + #[inline] + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + self.borrow().fmt(f) + } +} + +// Safety: Same bounds as `std::borrow::Cow`. +unsafe impl<T, U> Sync for Cow<'_, T, U> +where + U: Capacity, + T: Beef + Sync + ?Sized, + T::Owned: Sync, +{ +} + +unsafe impl<T, U> Send for Cow<'_, T, U> +where + U: Capacity, + T: Beef + Sync + ?Sized, + T::Owned: Send, +{ +} + +impl<T, U> Unpin for Cow<'_, T, U> +where + U: Capacity, + T: Beef + ?Sized, + T::Owned: Unpin, +{ +} diff --git a/vendor/beef/src/lean.rs b/vendor/beef/src/lean.rs new file mode 100644 index 00000000..cb3c1943 --- /dev/null +++ b/vendor/beef/src/lean.rs @@ -0,0 +1,69 @@ +//! Namespace containing the 2-word `Cow` implementation. + +use crate::traits::Capacity; + +/// Faster, 2-word `Cow`. This version is available only on 64-bit architecture, +/// and it puts both capacity and length together in a fat pointer. Both length and capacity +/// is limited to 32 bits. +/// +/// # Panics +/// +/// [`Cow::owned`](../generic/struct.Cow.html#method.owned) will panic if capacity is larger than `u32::max_size()`. Use the +/// top level `beef::Cow` if you wish to avoid this problem. +pub type Cow<'a, T> = crate::generic::Cow<'a, T, Lean>; + +pub(crate) mod internal { + #[derive(Clone, Copy, PartialEq, Eq)] + pub struct Lean; +} +use internal::Lean; + +const MASK_LO: usize = u32::MAX as usize; +const MASK_HI: usize = !MASK_LO; + +impl Lean { + #[inline] + pub const fn mask_len(len: usize) -> usize { + len & MASK_LO + } +} + +impl Capacity for Lean { + type Field = Lean; + type NonZero = Lean; + + #[inline] + fn len(fat: usize) -> usize { + fat & MASK_LO + } + + #[inline] + fn empty(len: usize) -> (usize, Lean) { + (len & MASK_LO, Lean) + } + + #[inline] + fn store(len: usize, capacity: usize) -> (usize, Lean) { + if capacity & MASK_HI != 0 { + panic!("beef::lean::Cow: Capacity out of bounds"); + } + + let fat = ((capacity & MASK_LO) << 32) | (len & MASK_LO); + + (fat, Lean) + } + + #[inline] + fn unpack(fat: usize, _: Lean) -> (usize, usize) { + (fat & MASK_LO, (fat & MASK_HI) >> 32) + } + + #[inline] + fn maybe(fat: usize, _: Lean) -> Option<Lean> { + if fat & MASK_HI != 0 { + Some(Lean) + } else { + None + } + } +} diff --git a/vendor/beef/src/lib.rs b/vendor/beef/src/lib.rs new file mode 100644 index 00000000..62a503a3 --- /dev/null +++ b/vendor/beef/src/lib.rs @@ -0,0 +1,285 @@ +//! Faster, more compact implementation of `Cow`. +//! +//! **[Changelog](https://github.com/maciejhirsz/beef/releases) -** +//! **[Cargo](https://crates.io/crates/beef) -** +//! **[Repository](https://github.com/maciejhirsz/beef)** +//! +//! ```rust +//! use beef::Cow; +//! +//! let borrowed: Cow<str> = Cow::borrowed("Hello"); +//! let owned: Cow<str> = Cow::owned(String::from("World")); +//! +//! assert_eq!( +//! format!("{} {}!", borrowed, owned), +//! "Hello World!", +//! ); +//! ``` +//! +//! There are two versions of `Cow` exposed by this crate: +//! +//! + `beef::Cow` is 3 words wide: pointer, length, and capacity. It stores the ownership tag in capacity. +//! + `beef::lean::Cow` is 2 words wide, storing length, capacity, and the ownership tag all in one word. +//! +//! Both versions are leaner than the `std::borrow::Cow`: +//! +//! ```rust +//! use std::mem::size_of; +//! +//! const WORD: usize = size_of::<usize>(); +//! +//! assert_eq!(size_of::<std::borrow::Cow<str>>(), 4 * WORD); +//! assert_eq!(size_of::<beef::Cow<str>>(), 3 * WORD); +//! +//! // Lean variant is two words on 64-bit architecture +//! #[cfg(target_pointer_width = "64")] +//! assert_eq!(size_of::<beef::lean::Cow<str>>(), 2 * WORD); +//! ``` +#![cfg_attr(feature = "const_fn", feature(const_fn_trait_bound))] +#![warn(missing_docs)] +#![cfg_attr(not(test), no_std)] +extern crate alloc; + +mod traits; +mod wide; + +#[cfg(feature = "impl_serde")] +mod serde; + +pub mod generic; +#[cfg(target_pointer_width = "64")] +pub mod lean; + +#[cfg(not(target_pointer_width = "64"))] +pub mod lean { + /// Re-exports 3-word Cow for non-64-bit targets + pub use super::wide::Cow; +} + +pub use wide::Cow; + +#[rustfmt::skip] +macro_rules! test { ($tmod:ident => $cow:path) => { + #[cfg(test)] + mod $tmod { + use $cow; + + #[test] + fn borrowed_str() { + let s = "Hello World"; + let c = Cow::borrowed(s); + + assert_eq!(s, c); + assert_eq!(s, c.as_ref()); + assert_eq!(s, &*c); + } + + #[test] + fn owned_string() { + let s = String::from("Hello World"); + let c: Cow<str> = Cow::owned(s.clone()); + + assert_eq!(s, c); + } + + #[test] + fn into_owned() { + let hello = "Hello World"; + let borrowed = Cow::borrowed(hello); + let owned: Cow<str> = Cow::owned(String::from(hello)); + + assert_eq!(borrowed.into_owned(), hello); + assert_eq!(owned.into_owned(), hello); + } + + #[test] + fn borrowed_slice() { + let s: &[_] = &[1, 2, 42]; + let c = Cow::borrowed(s); + + assert_eq!(s, c); + assert_eq!(s, c.as_ref()); + assert_eq!(s, &*c); + } + + #[test] + fn owned_slice() { + let s = vec![1, 2, 42]; + let c: Cow<[_]> = Cow::owned(s.clone()); + + assert_eq!(s, c); + } + + #[test] + fn into_owned_vec() { + let hello: &[u8] = b"Hello World"; + let borrowed = Cow::borrowed(hello); + let owned: Cow<[u8]> = Cow::owned(hello.to_vec()); + + assert_eq!(borrowed.into_owned(), hello); + assert_eq!(owned.into_owned(), hello); + } + + #[test] + fn hash() { + use std::collections::hash_map::DefaultHasher; + use std::hash::{Hash, Hasher}; + + let slice = "Hello World!"; + let borrowed = Cow::borrowed(slice); + let owned: Cow<str> = Cow::owned(slice.to_owned()); + + let hash1 = { + let mut hasher = DefaultHasher::default(); + + slice.hash(&mut hasher); + + hasher.finish() + }; + + let hash2 = { + let mut hasher = DefaultHasher::default(); + + borrowed.hash(&mut hasher); + + hasher.finish() + }; + + let hash3 = { + let mut hasher = DefaultHasher::default(); + + owned.hash(&mut hasher); + + hasher.finish() + }; + + assert_eq!(hash1, hash2); + assert_eq!(hash1, hash3); + assert_eq!(hash2, hash3); + } + + #[test] + fn ord_and_partial_ord() { + use std::cmp::Ordering; + + macro_rules! generate_order_tests { + ( $f:tt => $order:expr => $left:expr, $right:expr ) => { + assert_eq!( + Cow::<str>::borrowed($left).$f(&Cow::<str>::borrowed($right)), + $order + ); + + assert_eq!( + Cow::<str>::owned($left.to_owned()) + .$f(&Cow::<str>::borrowed($right)), + $order + ); + + assert_eq!( + Cow::<str>::borrowed($left) + .$f(&Cow::<str>::owned($right.to_owned())), + $order + ); + + assert_eq!( + Cow::<str>::owned($left.to_owned()) + .$f(&Cow::<str>::owned($right.to_owned())), + $order + ); + } + } + + generate_order_tests!(partial_cmp => Some(Ordering::Equal) => "a", "a"); + generate_order_tests!(partial_cmp => Some(Ordering::Less) => "a", "b"); + generate_order_tests!(partial_cmp => Some(Ordering::Greater) => "b", "a"); + + generate_order_tests!(cmp => Ordering::Equal => "a", "a"); + generate_order_tests!(cmp => Ordering::Less => "a", "b"); + generate_order_tests!(cmp => Ordering::Greater => "b", "a"); + } + + #[test] + fn from_std_cow() { + let std = std::borrow::Cow::Borrowed("Hello World"); + let beef = Cow::from(std.clone()); + + assert_eq!(&*std, &*beef); + } + + #[test] + fn unwrap_borrowed() { + let borrowed = Cow::borrowed("Hello"); + + assert_eq!(borrowed.unwrap_borrowed(), "Hello"); + } + + #[test] + #[should_panic] + fn unwrap_owned() { + let borrowed: Cow<str> = Cow::owned("Hello".to_string()); + + borrowed.unwrap_borrowed(); + } + + #[test] + fn stress_test_owned() { + let mut expected = String::from("Hello... "); + let mut cow: Cow<str> = Cow::borrowed("Hello... "); + + #[cfg(not(miri))] + let iterations = 1024; + #[cfg(miri)] + let iterations = 10; + + for i in 0..iterations { + if i % 3 == 0 { + let old = cow; + cow = old.clone(); + + std::mem::drop(old); + } + + let mut owned = cow.into_owned(); + + expected.push_str("Hello?.. "); + owned.push_str("Hello?.. "); + + cow = owned.into(); + } + + assert_eq!(expected, cow.into_owned()); + } + + #[test] + fn const_fn_str() { + const HELLO: Cow<str> = Cow::const_str("Hello"); + + assert_eq!(&*HELLO, "Hello"); + } + + #[test] + #[cfg(feature = "const_fn")] + fn const_fn_slice() { + const FOO: Cow<[u8]> = Cow::const_slice(b"bar"); + + assert_eq!(&*FOO, b"bar"); + } + + #[test] + fn default_str() { + let empty: Cow<str> = Default::default(); + + assert_eq!(&*empty, ""); + } + + #[test] + fn default_slice() { + let empty: Cow<[u8]> = Default::default(); + + assert_eq!(&*empty, b""); + } + } +} } + +test!(test_wide => crate::wide::Cow); +test!(test_lean => crate::lean::Cow); diff --git a/vendor/beef/src/serde.rs b/vendor/beef/src/serde.rs new file mode 100644 index 00000000..a85fbc6f --- /dev/null +++ b/vendor/beef/src/serde.rs @@ -0,0 +1,149 @@ +use alloc::{borrow::ToOwned, string::String}; +use core::{fmt, marker::PhantomData}; + +use serde::de::{self, Deserialize, Deserializer, Visitor}; +use serde::ser::{Serialize, Serializer}; + +use crate::generic::Cow; +use crate::traits::internal::{Beef, Capacity}; + +impl<T, U> Serialize for Cow<'_, T, U> +where + T: Beef + Serialize + ?Sized, + U: Capacity, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + T::serialize(self.as_ref(), serializer) + } +} + +struct CowVisitor<'de, 'a, T: Beef + ?Sized, U: Capacity>( + PhantomData<fn() -> (&'de T, Cow<'a, T, U>)>, +); + +impl<'de, 'a, U> Visitor<'de> for CowVisitor<'de, 'a, str, U> +where + 'de: 'a, + U: Capacity, +{ + type Value = Cow<'a, str, U>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a string") + } + + fn visit_borrowed_str<E>(self, value: &'de str) -> Result<Self::Value, E> + where + E: de::Error, + { + Ok(Cow::borrowed(value)) + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: de::Error, + { + Ok(Cow::owned(value.to_owned())) + } + + fn visit_string<E>(self, value: String) -> Result<Self::Value, E> + where + E: de::Error, + { + Ok(Cow::owned(value)) + } +} + +impl<'de, 'a, U> Deserialize<'de> for Cow<'a, str, U> +where + 'de: 'a, + U: Capacity, +{ + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_str(CowVisitor::<'de, 'a, str, U>(PhantomData)) + } +} + +impl<'de, 'a, T, U> Deserialize<'de> for Cow<'a, [T], U> +where + [T]: Beef, + U: Capacity, + <[T] as ToOwned>::Owned: Deserialize<'de>, +{ + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + <[T] as ToOwned>::Owned::deserialize(deserializer).map(Cow::owned) + } +} + +#[cfg(test)] +mod tests { + use serde_derive::{Deserialize, Serialize}; + + #[test] + fn wide_cow_de() { + use crate::Cow; + + #[derive(Serialize, Deserialize)] + struct Test<'a> { + #[serde(borrow)] + foo: Cow<'a, str>, + bar: Cow<'a, str>, + } + + let json = r#"{"foo":"Hello","bar":"\tWorld!"}"#; + let test: Test = serde_json::from_str(json).unwrap(); + + assert_eq!(test.foo, "Hello"); + assert_eq!(test.bar, "\tWorld!"); + + assert!(test.foo.is_borrowed()); + assert!(test.bar.is_owned()); + + let out = serde_json::to_string(&test).unwrap(); + + assert_eq!(json, out); + } + + #[test] + fn wide_cow_direct() { + use crate::Cow; + + let json = r#""foo""#; + let cow: Cow<str> = serde_json::from_str(json).unwrap(); + + assert_eq!(cow, "foo"); + + assert!(cow.is_borrowed()); + + let json = r#""\tfoo""#; + let cow: Cow<str> = serde_json::from_str(json).unwrap(); + + assert_eq!(cow, "\tfoo"); + + assert!(cow.is_owned()); + } + + #[test] + fn wide_cow_direct_bytes() { + use crate::Cow; + + let json = r#"[102, 111, 111]"#; + let cow: Cow<[u8]> = serde_json::from_str(json).unwrap(); + + assert_eq!(cow, &b"foo"[..]); + + // We need to stay generic over `[T]`, so no specialization for byte slices + assert!(cow.is_owned()); + } +} diff --git a/vendor/beef/src/traits.rs b/vendor/beef/src/traits.rs new file mode 100644 index 00000000..4be2d2d0 --- /dev/null +++ b/vendor/beef/src/traits.rs @@ -0,0 +1,175 @@ +pub(crate) use internal::Beef; +pub(crate) use internal::Capacity; + +pub(crate) mod internal { + use alloc::borrow::ToOwned; + use alloc::string::String; + use alloc::vec::Vec; + use core::mem::ManuallyDrop; + use core::ptr::{slice_from_raw_parts, NonNull}; + + pub trait Capacity { + type Field: Copy; + type NonZero: Copy; + + fn len(fat: usize) -> usize; + + fn empty(len: usize) -> (usize, Self::Field); + + fn store(len: usize, capacity: usize) -> (usize, Self::Field); + + fn unpack(fat: usize, capacity: Self::NonZero) -> (usize, usize); + + fn maybe(fat: usize, capacity: Self::Field) -> Option<Self::NonZero>; + } + + /// Helper trait required by `Cow<T>` to extract capacity of owned + /// variant of `T`, and manage conversions. + /// + /// This can be only implemented on types that match requirements: + /// + /// + `T::Owned` has a `capacity`, which is an extra word that is absent in `T`. + /// + `T::Owned` with `capacity` of `0` does not allocate memory. + /// + `T::Owned` can be reconstructed from `*mut T` borrowed out of it, plus capacity. + pub unsafe trait Beef: ToOwned { + type PointerT; + + fn ref_into_parts<U>(&self) -> (NonNull<Self::PointerT>, usize, U::Field) + where + U: Capacity; + + unsafe fn ref_from_parts<U>(ptr: NonNull<Self::PointerT>, len: usize) -> *const Self + where + U: Capacity; + + /// Convert `T::Owned` to `NonNull<T>` and capacity. + /// Return `None` for `0` capacity. + fn owned_into_parts<U>(owned: Self::Owned) -> (NonNull<Self::PointerT>, usize, U::Field) + where + U: Capacity; + + /// Rebuild `T::Owned` from `NonNull<T>` and `capacity`. This can be done by the likes + /// of [`Vec::from_raw_parts`](https://doc.rust-lang.org/std/vec/struct.Vec.html#method.from_raw_parts). + unsafe fn owned_from_parts<U>( + ptr: NonNull<Self::PointerT>, + fat: usize, + capacity: U::NonZero, + ) -> Self::Owned + where + U: Capacity; + } + + unsafe impl Beef for str { + type PointerT = u8; + + #[inline] + fn ref_into_parts<U>(&self) -> (NonNull<u8>, usize, U::Field) + where + U: Capacity, + { + let (fat, cap) = U::empty(self.len()); + + // A note on soundness: + // + // We are casting *const T to *mut T, however for all borrowed values + // this raw pointer is only ever dereferenced back to &T. + ( + unsafe { NonNull::new_unchecked(self.as_ptr() as *mut u8) }, + fat, + cap, + ) + } + + #[inline] + unsafe fn ref_from_parts<U>(ptr: NonNull<u8>, fat: usize) -> *const str + where + U: Capacity, + { + slice_from_raw_parts(ptr.as_ptr(), U::len(fat)) as *const str + } + + #[inline] + fn owned_into_parts<U>(owned: String) -> (NonNull<u8>, usize, U::Field) + where + U: Capacity, + { + // Convert to `String::into_raw_parts` once stabilized + // We need to go through Vec here to get provenance for the entire allocation + // instead of just the initialized parts. + let mut owned = ManuallyDrop::new(owned.into_bytes()); + let (fat, cap) = U::store(owned.len(), owned.capacity()); + + ( + unsafe { NonNull::new_unchecked(owned.as_mut_ptr()) }, + fat, + cap, + ) + } + + #[inline] + unsafe fn owned_from_parts<U>(ptr: NonNull<u8>, fat: usize, capacity: U::NonZero) -> String + where + U: Capacity, + { + let (len, cap) = U::unpack(fat, capacity); + + String::from_utf8_unchecked(Vec::from_raw_parts(ptr.as_ptr(), len, cap)) + } + } + + unsafe impl<T: Clone> Beef for [T] { + type PointerT = T; + + #[inline] + fn ref_into_parts<U>(&self) -> (NonNull<T>, usize, U::Field) + where + U: Capacity, + { + let (fat, cap) = U::empty(self.len()); + + // A note on soundness: + // + // We are casting *const T to *mut T, however for all borrowed values + // this raw pointer is only ever dereferenced back to &T. + ( + unsafe { NonNull::new_unchecked(self.as_ptr() as *mut T) }, + fat, + cap, + ) + } + + #[inline] + unsafe fn ref_from_parts<U>(ptr: NonNull<T>, fat: usize) -> *const [T] + where + U: Capacity, + { + slice_from_raw_parts(ptr.as_ptr(), U::len(fat)) + } + + #[inline] + fn owned_into_parts<U>(owned: Vec<T>) -> (NonNull<T>, usize, U::Field) + where + U: Capacity, + { + // Convert to `Vec::into_raw_parts` once stabilized + let mut owned = ManuallyDrop::new(owned); + let (fat, cap) = U::store(owned.len(), owned.capacity()); + + ( + unsafe { NonNull::new_unchecked(owned.as_mut_ptr()) }, + fat, + cap, + ) + } + + #[inline] + unsafe fn owned_from_parts<U>(ptr: NonNull<T>, fat: usize, capacity: U::NonZero) -> Vec<T> + where + U: Capacity, + { + let (len, cap) = U::unpack(fat, capacity); + + Vec::from_raw_parts(ptr.as_ptr(), len, cap) + } + } +} diff --git a/vendor/beef/src/wide.rs b/vendor/beef/src/wide.rs new file mode 100644 index 00000000..466e594c --- /dev/null +++ b/vendor/beef/src/wide.rs @@ -0,0 +1,42 @@ +use crate::traits::Capacity; +use core::num::NonZeroUsize; + +/// Compact three word `Cow` that puts the ownership tag in capacity. +/// This is a type alias, for documentation see [`beef::generic::Cow`](./generic/struct.Cow.html). +pub type Cow<'a, T> = crate::generic::Cow<'a, T, Wide>; + +pub(crate) mod internal { + #[derive(Clone, Copy, PartialEq, Eq)] + pub struct Wide; +} +use internal::Wide; + +impl Capacity for Wide { + type Field = Option<NonZeroUsize>; + type NonZero = NonZeroUsize; + + #[inline] + fn len(fat: usize) -> usize { + fat + } + + #[inline] + fn empty(len: usize) -> (usize, Self::Field) { + (len, None) + } + + #[inline] + fn store(len: usize, capacity: usize) -> (usize, Self::Field) { + (len, NonZeroUsize::new(capacity)) + } + + #[inline] + fn unpack(fat: usize, capacity: NonZeroUsize) -> (usize, usize) { + (fat, capacity.get()) + } + + #[inline] + fn maybe(_: usize, capacity: Option<NonZeroUsize>) -> Option<NonZeroUsize> { + capacity + } +} |
