diff options
Diffstat (limited to 'third_party/rust/proc-macro2/src/rcvec.rs')
-rw-r--r-- | third_party/rust/proc-macro2/src/rcvec.rs | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/third_party/rust/proc-macro2/src/rcvec.rs b/third_party/rust/proc-macro2/src/rcvec.rs new file mode 100644 index 0000000000..37955afb11 --- /dev/null +++ b/third_party/rust/proc-macro2/src/rcvec.rs @@ -0,0 +1,145 @@ +use alloc::rc::Rc; +use alloc::vec; +use core::mem; +use core::panic::RefUnwindSafe; +use core::slice; + +pub(crate) struct RcVec<T> { + inner: Rc<Vec<T>>, +} + +pub(crate) struct RcVecBuilder<T> { + inner: Vec<T>, +} + +pub(crate) struct RcVecMut<'a, T> { + inner: &'a mut Vec<T>, +} + +#[derive(Clone)] +pub(crate) struct RcVecIntoIter<T> { + inner: vec::IntoIter<T>, +} + +impl<T> RcVec<T> { + pub fn is_empty(&self) -> bool { + self.inner.is_empty() + } + + pub fn len(&self) -> usize { + self.inner.len() + } + + pub fn iter(&self) -> slice::Iter<T> { + self.inner.iter() + } + + pub fn make_mut(&mut self) -> RcVecMut<T> + where + T: Clone, + { + RcVecMut { + inner: Rc::make_mut(&mut self.inner), + } + } + + pub fn get_mut(&mut self) -> Option<RcVecMut<T>> { + let inner = Rc::get_mut(&mut self.inner)?; + Some(RcVecMut { inner }) + } + + pub fn make_owned(mut self) -> RcVecBuilder<T> + where + T: Clone, + { + let vec = if let Some(owned) = Rc::get_mut(&mut self.inner) { + mem::take(owned) + } else { + Vec::clone(&self.inner) + }; + RcVecBuilder { inner: vec } + } +} + +impl<T> RcVecBuilder<T> { + pub fn new() -> Self { + RcVecBuilder { inner: Vec::new() } + } + + pub fn with_capacity(cap: usize) -> Self { + RcVecBuilder { + inner: Vec::with_capacity(cap), + } + } + + pub fn push(&mut self, element: T) { + self.inner.push(element); + } + + pub fn extend(&mut self, iter: impl IntoIterator<Item = T>) { + self.inner.extend(iter); + } + + pub fn as_mut(&mut self) -> RcVecMut<T> { + RcVecMut { + inner: &mut self.inner, + } + } + + pub fn build(self) -> RcVec<T> { + RcVec { + inner: Rc::new(self.inner), + } + } +} + +impl<'a, T> RcVecMut<'a, T> { + pub fn push(&mut self, element: T) { + self.inner.push(element); + } + + pub fn extend(&mut self, iter: impl IntoIterator<Item = T>) { + self.inner.extend(iter); + } + + pub fn pop(&mut self) -> Option<T> { + self.inner.pop() + } + + pub fn as_mut(&mut self) -> RcVecMut<T> { + RcVecMut { inner: self.inner } + } +} + +impl<T> Clone for RcVec<T> { + fn clone(&self) -> Self { + RcVec { + inner: Rc::clone(&self.inner), + } + } +} + +impl<T> IntoIterator for RcVecBuilder<T> { + type Item = T; + type IntoIter = RcVecIntoIter<T>; + + fn into_iter(self) -> Self::IntoIter { + RcVecIntoIter { + inner: self.inner.into_iter(), + } + } +} + +impl<T> Iterator for RcVecIntoIter<T> { + type Item = T; + + fn next(&mut self) -> Option<Self::Item> { + self.inner.next() + } + + fn size_hint(&self) -> (usize, Option<usize>) { + self.inner.size_hint() + } +} + +impl<T> RefUnwindSafe for RcVec<T> where T: RefUnwindSafe {} |