xref: /linux/rust/proc-macro2/rcvec.rs (revision 784faa8eca8270671e0ed6d9d21f04bbb80fc5f7)
1 // SPDX-License-Identifier: Apache-2.0 OR MIT
2 
3 use alloc::rc::Rc;
4 use alloc::vec;
5 use core::mem;
6 use core::panic::RefUnwindSafe;
7 use core::slice;
8 
9 pub(crate) struct RcVec<T> {
10     inner: Rc<Vec<T>>,
11 }
12 
13 pub(crate) struct RcVecBuilder<T> {
14     inner: Vec<T>,
15 }
16 
17 pub(crate) struct RcVecMut<'a, T> {
18     inner: &'a mut Vec<T>,
19 }
20 
21 #[derive(Clone)]
22 pub(crate) struct RcVecIntoIter<T> {
23     inner: vec::IntoIter<T>,
24 }
25 
26 impl<T> RcVec<T> {
is_empty(&self) -> bool27     pub(crate) fn is_empty(&self) -> bool {
28         self.inner.is_empty()
29     }
30 
len(&self) -> usize31     pub(crate) fn len(&self) -> usize {
32         self.inner.len()
33     }
34 
iter(&self) -> slice::Iter<T>35     pub(crate) fn iter(&self) -> slice::Iter<T> {
36         self.inner.iter()
37     }
38 
make_mut(&mut self) -> RcVecMut<T> where T: Clone,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 
get_mut(&mut self) -> Option<RcVecMut<T>>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 
make_owned(mut self) -> RcVecBuilder<T> where T: Clone,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 
66 impl<T> RcVecBuilder<T> {
new() -> Self67     pub(crate) fn new() -> Self {
68         RcVecBuilder { inner: Vec::new() }
69     }
70 
with_capacity(cap: usize) -> Self71     pub(crate) fn with_capacity(cap: usize) -> Self {
72         RcVecBuilder {
73             inner: Vec::with_capacity(cap),
74         }
75     }
76 
push(&mut self, element: T)77     pub(crate) fn push(&mut self, element: T) {
78         self.inner.push(element);
79     }
80 
extend(&mut self, iter: impl IntoIterator<Item = T>)81     pub(crate) fn extend(&mut self, iter: impl IntoIterator<Item = T>) {
82         self.inner.extend(iter);
83     }
84 
as_mut(&mut self) -> RcVecMut<T>85     pub(crate) fn as_mut(&mut self) -> RcVecMut<T> {
86         RcVecMut {
87             inner: &mut self.inner,
88         }
89     }
90 
build(self) -> RcVec<T>91     pub(crate) fn build(self) -> RcVec<T> {
92         RcVec {
93             inner: Rc::new(self.inner),
94         }
95     }
96 }
97 
98 impl<'a, T> RcVecMut<'a, T> {
push(&mut self, element: T)99     pub(crate) fn push(&mut self, element: T) {
100         self.inner.push(element);
101     }
102 
extend(&mut self, iter: impl IntoIterator<Item = T>)103     pub(crate) fn extend(&mut self, iter: impl IntoIterator<Item = T>) {
104         self.inner.extend(iter);
105     }
106 
as_mut(&mut self) -> RcVecMut<T>107     pub(crate) fn as_mut(&mut self) -> RcVecMut<T> {
108         RcVecMut { inner: self.inner }
109     }
110 
take(self) -> RcVecBuilder<T>111     pub(crate) fn take(self) -> RcVecBuilder<T> {
112         let vec = mem::take(self.inner);
113         RcVecBuilder { inner: vec }
114     }
115 }
116 
117 impl<T> Clone for RcVec<T> {
clone(&self) -> Self118     fn clone(&self) -> Self {
119         RcVec {
120             inner: Rc::clone(&self.inner),
121         }
122     }
123 }
124 
125 impl<T> IntoIterator for RcVecBuilder<T> {
126     type Item = T;
127     type IntoIter = RcVecIntoIter<T>;
128 
into_iter(self) -> Self::IntoIter129     fn into_iter(self) -> Self::IntoIter {
130         RcVecIntoIter {
131             inner: self.inner.into_iter(),
132         }
133     }
134 }
135 
136 impl<T> Iterator for RcVecIntoIter<T> {
137     type Item = T;
138 
next(&mut self) -> Option<Self::Item>139     fn next(&mut self) -> Option<Self::Item> {
140         self.inner.next()
141     }
142 
size_hint(&self) -> (usize, Option<usize>)143     fn size_hint(&self) -> (usize, Option<usize>) {
144         self.inner.size_hint()
145     }
146 }
147 
148 impl<T> RefUnwindSafe for RcVec<T> where T: RefUnwindSafe {}
149