error[E0271]: type mismatch resolving `<std::iter::TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 9:6 found_e:_]> as std::iter::Iterator>::Item == &_`
  --> $DIR/issue-31173.rs:10:10
   |
LL |         .cloned()
   |          ^^^^^^ expected u8, found reference
   |
   = note: expected type `u8`
              found type `&_`

error[E0599]: no method named `collect` found for type `std::iter::Cloned<std::iter::TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 9:6 found_e:_]>>` in the current scope
  --> $DIR/issue-31173.rs:14:10
   |
LL |         .collect();
   |          ^^^^^^^
   |
   = note: the method `collect` exists but the following trait bounds were not satisfied:
           `&mut std::iter::Cloned<std::iter::TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 9:6 found_e:_]>> : std::iter::Iterator`
           `std::iter::Cloned<std::iter::TakeWhile<&mut std::vec::IntoIter<u8>, [closure@$DIR/issue-31173.rs:6:39: 9:6 found_e:_]>> : std::iter::Iterator`

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0271, E0599.
For more information about an error, try `rustc --explain E0271`.