rcvec.rs

  1// SPDX-License-Identifier: Apache-2.0 OR MIT
  2
  3use alloc::rc::Rc;
  4use alloc::vec;
  5use core::mem;
  6use core::panic::RefUnwindSafe;
  7use core::slice;
  8
  9pub(crate) struct RcVec<T> {
 10    inner: Rc<Vec<T>>,
 11}
 12
 13pub(crate) struct RcVecBuilder<T> {
 14    inner: Vec<T>,
 15}
 16
 17pub(crate) struct RcVecMut<'a, T> {
 18    inner: &'a mut Vec<T>,
 19}
 20
 21#[derive(Clone)]
 22pub(crate) struct RcVecIntoIter<T> {
 23    inner: vec::IntoIter<T>,
 24}
 25
 26impl<T> RcVec<T> {
 27    pub(crate) fn is_empty(&self) -> bool {
 28        self.inner.is_empty()
 29    }
 30
 31    pub(crate) fn len(&self) -> usize {
 32        self.inner.len()
 33    }
 34
 35    pub(crate) fn iter(&self) -> slice::Iter<T> {
 36        self.inner.iter()
 37    }
 38
 39    pub(crate) fn make_mut(&mut self) -> RcVecMut<T>
 40    where
 41        T: Clone,
 42    {
 43        RcVecMut {
 44            inner: Rc::make_mut(&mut self.inner),
 45        }
 46    }
 47
 48    pub(crate) fn get_mut(&mut self) -> Option<RcVecMut<T>> {
 49        let inner = Rc::get_mut(&mut self.inner)?;
 50        Some(RcVecMut { inner })
 51    }
 52
 53    pub(crate) fn make_owned(mut self) -> RcVecBuilder<T>
 54    where
 55        T: Clone,
 56    {
 57        let vec = if let Some(owned) = Rc::get_mut(&mut self.inner) {
 58            mem::take(owned)
 59        } else {
 60            Vec::clone(&self.inner)
 61        };
 62        RcVecBuilder { inner: vec }
 63    }
 64}
 65
 66impl<T> RcVecBuilder<T> {
 67    pub(crate) fn new() -> Self {
 68        RcVecBuilder { inner: Vec::new() }
 69    }
 70
 71    pub(crate) fn with_capacity(cap: usize) -> Self {
 72        RcVecBuilder {
 73            inner: Vec::with_capacity(cap),
 74        }
 75    }
 76
 77    pub(crate) fn push(&mut self, element: T) {
 78        self.inner.push(element);
 79    }
 80
 81    pub(crate) fn extend(&mut self, iter: impl IntoIterator<Item = T>) {
 82        self.inner.extend(iter);
 83    }
 84
 85    pub(crate) fn as_mut(&mut self) -> RcVecMut<T> {
 86        RcVecMut {
 87            inner: &mut self.inner,
 88        }
 89    }
 90
 91    pub(crate) fn build(self) -> RcVec<T> {
 92        RcVec {
 93            inner: Rc::new(self.inner),
 94        }
 95    }
 96}
 97
 98impl<'a, T> RcVecMut<'a, T> {
 99    pub(crate) fn push(&mut self, element: T) {
100        self.inner.push(element);
101    }
102
103    pub(crate) fn extend(&mut self, iter: impl IntoIterator<Item = T>) {
104        self.inner.extend(iter);
105    }
106
107    pub(crate) fn as_mut(&mut self) -> RcVecMut<T> {
108        RcVecMut { inner: self.inner }
109    }
110
111    pub(crate) fn take(self) -> RcVecBuilder<T> {
112        let vec = mem::take(self.inner);
113        RcVecBuilder { inner: vec }
114    }
115}
116
117impl<T> Clone for RcVec<T> {
118    fn clone(&self) -> Self {
119        RcVec {
120            inner: Rc::clone(&self.inner),
121        }
122    }
123}
124
125impl<T> IntoIterator for RcVecBuilder<T> {
126    type Item = T;
127    type IntoIter = RcVecIntoIter<T>;
128
129    fn into_iter(self) -> Self::IntoIter {
130        RcVecIntoIter {
131            inner: self.inner.into_iter(),
132        }
133    }
134}
135
136impl<T> Iterator for RcVecIntoIter<T> {
137    type Item = T;
138
139    fn next(&mut self) -> Option<Self::Item> {
140        self.inner.next()
141    }
142
143    fn size_hint(&self) -> (usize, Option<usize>) {
144        self.inner.size_hint()
145    }
146}
147
148impl<T> RefUnwindSafe for RcVec<T> where T: RefUnwindSafe {}