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-rw-r--r--compiler/rustc_data_structures/src/thin_vec.rs135
1 files changed, 0 insertions, 135 deletions
diff --git a/compiler/rustc_data_structures/src/thin_vec.rs b/compiler/rustc_data_structures/src/thin_vec.rs
deleted file mode 100644
index 716259142..000000000
--- a/compiler/rustc_data_structures/src/thin_vec.rs
+++ /dev/null
@@ -1,135 +0,0 @@
-use crate::stable_hasher::{HashStable, StableHasher};
-
-use std::iter::FromIterator;
-
-/// A vector type optimized for cases where this size is usually 0 (cf. `SmallVec`).
-/// The `Option<Box<..>>` wrapping allows us to represent a zero sized vector with `None`,
-/// which uses only a single (null) pointer.
-#[derive(Clone, Encodable, Decodable, Debug, Hash, Eq, PartialEq)]
-pub struct ThinVec<T>(Option<Box<Vec<T>>>);
-
-impl<T> ThinVec<T> {
- pub fn new() -> Self {
- ThinVec(None)
- }
-
- pub fn iter(&self) -> std::slice::Iter<'_, T> {
- self.into_iter()
- }
-
- pub fn iter_mut(&mut self) -> std::slice::IterMut<'_, T> {
- self.into_iter()
- }
-
- pub fn push(&mut self, item: T) {
- match *self {
- ThinVec(Some(ref mut vec)) => vec.push(item),
- ThinVec(None) => *self = vec![item].into(),
- }
- }
-}
-
-impl<T> From<Vec<T>> for ThinVec<T> {
- fn from(vec: Vec<T>) -> Self {
- if vec.is_empty() { ThinVec(None) } else { ThinVec(Some(Box::new(vec))) }
- }
-}
-
-impl<T> Into<Vec<T>> for ThinVec<T> {
- fn into(self) -> Vec<T> {
- match self {
- ThinVec(None) => Vec::new(),
- ThinVec(Some(vec)) => *vec,
- }
- }
-}
-
-impl<T> ::std::ops::Deref for ThinVec<T> {
- type Target = [T];
- fn deref(&self) -> &[T] {
- match *self {
- ThinVec(None) => &[],
- ThinVec(Some(ref vec)) => vec,
- }
- }
-}
-
-impl<T> ::std::ops::DerefMut for ThinVec<T> {
- fn deref_mut(&mut self) -> &mut [T] {
- match *self {
- ThinVec(None) => &mut [],
- ThinVec(Some(ref mut vec)) => vec,
- }
- }
-}
-
-impl<T> FromIterator<T> for ThinVec<T> {
- fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self {
- // `Vec::from_iter()` should not allocate if the iterator is empty.
- let vec: Vec<_> = iter.into_iter().collect();
- if vec.is_empty() { ThinVec(None) } else { ThinVec(Some(Box::new(vec))) }
- }
-}
-
-impl<T> IntoIterator for ThinVec<T> {
- type Item = T;
- type IntoIter = std::vec::IntoIter<T>;
-
- fn into_iter(self) -> Self::IntoIter {
- // This is still performant because `Vec::new()` does not allocate.
- self.0.map_or_else(Vec::new, |ptr| *ptr).into_iter()
- }
-}
-
-impl<'a, T> IntoIterator for &'a ThinVec<T> {
- type Item = &'a T;
- type IntoIter = std::slice::Iter<'a, T>;
-
- fn into_iter(self) -> Self::IntoIter {
- self.as_ref().iter()
- }
-}
-
-impl<'a, T> IntoIterator for &'a mut ThinVec<T> {
- type Item = &'a mut T;
- type IntoIter = std::slice::IterMut<'a, T>;
-
- fn into_iter(self) -> Self::IntoIter {
- self.as_mut().iter_mut()
- }
-}
-
-impl<T> Extend<T> for ThinVec<T> {
- fn extend<I: IntoIterator<Item = T>>(&mut self, iter: I) {
- match *self {
- ThinVec(Some(ref mut vec)) => vec.extend(iter),
- ThinVec(None) => *self = iter.into_iter().collect::<Vec<_>>().into(),
- }
- }
-
- fn extend_one(&mut self, item: T) {
- self.push(item)
- }
-
- fn extend_reserve(&mut self, additional: usize) {
- match *self {
- ThinVec(Some(ref mut vec)) => vec.reserve(additional),
- ThinVec(None) => *self = Vec::with_capacity(additional).into(),
- }
- }
-}
-
-impl<T: HashStable<CTX>, CTX> HashStable<CTX> for ThinVec<T> {
- fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
- (**self).hash_stable(hcx, hasher)
- }
-}
-
-impl<T> Default for ThinVec<T> {
- fn default() -> Self {
- Self(None)
- }
-}
-
-#[cfg(test)]
-mod tests;