array_chunks: remove Option wrapper from into_remainder's return type

library/core/src/iter/adapters/array_chunks.rs

@@ -40,17 +40,17 @@ where
  /// # // Also serves as a regression test for https://github.com/rust-lang/rust/issues/123333
  /// # #![feature(iter_array_chunks)]
  /// let x = [1,2,3,4,5].into_iter().array_chunks::<2>();
- /// let mut rem = x.into_remainder().unwrap();
+ /// let mut rem = x.into_remainder();
  /// assert_eq!(rem.next(), Some(5));
  /// assert_eq!(rem.next(), None);
  /// ```
  #[unstable(feature = "iter_array_chunks", reason = "recently added", issue = "100450")]
  #[inline]
- pub fn into_remainder(mut self) -> Option<array::IntoIter<I::Item, N>> {
- if self.remainder.is_none() {
- while let Some(_) = self.next() {}
+ pub fn into_remainder(mut self) -> array::IntoIter<I::Item, N> {
+ while self.remainder.is_none() {
+ let _ = self.next();
  }
- self.remainder
+ self.remainder.unwrap()
  }
 }
 

library/core/src/iter/traits/iterator.rs

@@ -3523,7 +3523,7 @@ pub trait Iterator {
  /// assert_eq!(iter.next(), Some(['l', 'o']));
  /// assert_eq!(iter.next(), Some(['r', 'e']));
  /// assert_eq!(iter.next(), None);
- /// assert_eq!(iter.into_remainder().unwrap().as_slice(), &['m']);
+ /// assert_eq!(iter.into_remainder().as_slice(), &['m']);
  /// ```
  ///
  /// ```

library/coretests/tests/iter/adapters/array_chunks.rs

@@ -18,10 +18,10 @@ fn test_iterator_array_chunks_clone_and_drop() {
  assert_eq!(count.get(), 3);
  let mut it2 = it.clone();
  assert_eq!(count.get(), 3);
- assert_eq!(it.into_remainder().unwrap().len(), 2);
+ assert_eq!(it.into_remainder().len(), 2);
  assert_eq!(count.get(), 5);
  assert!(it2.next().is_none());
- assert_eq!(it2.into_remainder().unwrap().len(), 2);
+ assert_eq!(it2.into_remainder().len(), 2);
  assert_eq!(count.get(), 7);
 }
 
@@ -31,7 +31,7 @@ fn test_iterator_array_chunks_remainder() {
  assert_eq!(it.next(), Some([0, 1, 2, 3]));
  assert_eq!(it.next(), Some([4, 5, 6, 7]));
  assert_eq!(it.next(), None);
- assert_eq!(it.into_remainder().unwrap().as_slice(), &[8, 9, 10]);
+ assert_eq!(it.into_remainder().as_slice(), &[8, 9, 10]);
 }
 
 #[test]
@@ -89,7 +89,7 @@ fn test_iterator_array_chunks_next_and_next_back() {
  assert_eq!(it.next(), None);
  assert_eq!(it.next_back(), None);
  assert_eq!(it.next(), None);
- assert_eq!(it.into_remainder().unwrap().as_slice(), &[9, 10]);
+ assert_eq!(it.into_remainder().as_slice(), &[9, 10]);
 }
 
 #[test]
@@ -102,7 +102,7 @@ fn test_iterator_array_chunks_rev_remainder() {
  assert_eq!(it.next(), None);
  assert_eq!(it.next(), None);
  }
- assert_eq!(it.into_remainder().unwrap().as_slice(), &[8, 9, 10]);
+ assert_eq!(it.into_remainder().as_slice(), &[8, 9, 10]);
 }
 
 #[test]