impl FusedIterator for all iterators

Author: cuviper

src/map.rs

@@ -12,7 +12,7 @@ use crate::vec::{self, Vec};
 use ::core::cmp::Ordering;
 use ::core::fmt;
 use ::core::hash::{BuildHasher, Hash, Hasher};
-use ::core::iter::FromIterator;
+use ::core::iter::{FromIterator, FusedIterator};
 use ::core::ops::{Index, IndexMut, RangeBounds};
 use ::core::slice::{Iter as SliceIter, IterMut as SliceIterMut};
 
@@ -822,6 +822,8 @@ impl<K, V> ExactSizeIterator for Keys<'_, K, V> {
     }
 }
 
+impl<K, V> FusedIterator for Keys<'_, K, V> {}
+
 // FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 impl<K, V> Clone for Keys<'_, K, V> {
     fn clone(&self) -> Self {
@@ -864,6 +866,8 @@ impl<K, V> ExactSizeIterator for IntoKeys<K, V> {
     }
 }
 
+impl<K, V> FusedIterator for IntoKeys<K, V> {}
+
 impl<K: fmt::Debug, V> fmt::Debug for IntoKeys<K, V> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
@@ -898,6 +902,8 @@ impl<K, V> ExactSizeIterator for Values<'_, K, V> {
     }
 }
 
+impl<K, V> FusedIterator for Values<'_, K, V> {}
+
 // FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 impl<K, V> Clone for Values<'_, K, V> {
     fn clone(&self) -> Self {
@@ -940,6 +946,8 @@ impl<K, V> ExactSizeIterator for ValuesMut<'_, K, V> {
     }
 }
 
+impl<K, V> FusedIterator for ValuesMut<'_, K, V> {}
+
 /// An owning iterator over the values of a `IndexMap`.
 ///
 /// This `struct` is created by the [`into_values`] method on [`IndexMap`].
@@ -967,6 +975,8 @@ impl<K, V> ExactSizeIterator for IntoValues<K, V> {
     }
 }
 
+impl<K, V> FusedIterator for IntoValues<K, V> {}
+
 impl<K, V: fmt::Debug> fmt::Debug for IntoValues<K, V> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let iter = self.iter.as_slice().iter().map(Bucket::value_ref);
@@ -1001,6 +1011,8 @@ impl<K, V> ExactSizeIterator for Iter<'_, K, V> {
     }
 }
 
+impl<K, V> FusedIterator for Iter<'_, K, V> {}
+
 // FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 impl<K, V> Clone for Iter<'_, K, V> {
     fn clone(&self) -> Self {
@@ -1043,6 +1055,8 @@ impl<K, V> ExactSizeIterator for IterMut<'_, K, V> {
     }
 }
 
+impl<K, V> FusedIterator for IterMut<'_, K, V> {}
+
 /// An owning iterator over the entries of a `IndexMap`.
 ///
 /// This `struct` is created by the [`into_iter`] method on [`IndexMap`]
@@ -1070,6 +1084,8 @@ impl<K, V> ExactSizeIterator for IntoIter<K, V> {
     }
 }
 
+impl<K, V> FusedIterator for IntoIter<K, V> {}
+
 impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for IntoIter<K, V> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let iter = self.iter.as_slice().iter().map(Bucket::refs);
@@ -1104,6 +1120,8 @@ impl<K, V> ExactSizeIterator for Drain<'_, K, V> {
     }
 }
 
+impl<K, V> FusedIterator for Drain<'_, K, V> {}
+
 impl<'a, K, V, S> IntoIterator for &'a IndexMap<K, V, S> {
     type Item = (&'a K, &'a V);
     type IntoIter = Iter<'a, K, V>;

src/set.rs

@@ -10,7 +10,7 @@ use crate::vec::{self, Vec};
 use core::cmp::Ordering;
 use core::fmt;
 use core::hash::{BuildHasher, Hash};
-use core::iter::{Chain, FromIterator};
+use core::iter::{Chain, FromIterator, FusedIterator};
 use core::ops::{BitAnd, BitOr, BitXor, Index, RangeBounds, Sub};
 use core::slice;
 
@@ -717,6 +717,8 @@ impl<T> ExactSizeIterator for IntoIter<T> {
     }
 }
 
+impl<T> FusedIterator for IntoIter<T> {}
+
 impl<T: fmt::Debug> fmt::Debug for IntoIter<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
@@ -751,6 +753,8 @@ impl<T> ExactSizeIterator for Iter<'_, T> {
     }
 }
 
+impl<T> FusedIterator for Iter<'_, T> {}
+
 impl<T> Clone for Iter<'_, T> {
     fn clone(&self) -> Self {
         Iter {
@@ -792,6 +796,8 @@ impl<T> ExactSizeIterator for Drain<'_, T> {
     }
 }
 
+impl<T> FusedIterator for Drain<'_, T> {}
+
 impl<'a, T, S> IntoIterator for &'a IndexSet<T, S> {
     type Item = &'a T;
     type IntoIter = Iter<'a, T>;
@@ -959,6 +965,13 @@ where
     }
 }
 
+impl<T, S> FusedIterator for Difference<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+}
+
 impl<T, S> Clone for Difference<'_, T, S> {
     fn clone(&self) -> Self {
         Difference {
@@ -1026,6 +1039,13 @@ where
     }
 }
 
+impl<T, S> FusedIterator for Intersection<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+}
+
 impl<T, S> Clone for Intersection<'_, T, S> {
     fn clone(&self) -> Self {
         Intersection {
@@ -1098,6 +1118,14 @@ where
     }
 }
 
+impl<T, S1, S2> FusedIterator for SymmetricDifference<'_, T, S1, S2>
+where
+    T: Eq + Hash,
+    S1: BuildHasher,
+    S2: BuildHasher,
+{
+}
+
 impl<T, S1, S2> Clone for SymmetricDifference<'_, T, S1, S2> {
     fn clone(&self) -> Self {
         SymmetricDifference {
@@ -1168,6 +1196,13 @@ where
     }
 }
 
+impl<T, S> FusedIterator for Union<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+}
+
 impl<T, S> Clone for Union<'_, T, S> {
     fn clone(&self) -> Self {
         Union {