Update references

Author: smoelius

tests/ui/borrow_box.stderr

@@ -22,6 +22,15 @@ error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
 LL |     fn test4(a: &Box<bool>);
    |                 ^^^^^^^^^^ help: try: `&bool`
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/borrow_box.rs:63:5
+   |
+LL |     let _ = foo;
+   |     ^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
   --> $DIR/borrow_box.rs:95:25
    |
@@ -64,5 +73,5 @@ error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
 LL | pub fn test20(_display: &Box<(dyn Display + Send)>) {}
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&(dyn Display + Send)`
 
-error: aborting due to 10 previous errors
+error: aborting due to 11 previous errors
 

tests/ui/borrow_interior_mutable_const/others.stderr

@@ -47,6 +47,15 @@ LL |     let _once_mut = &mut ONCE_INIT; //~ ERROR interior mutability
    |
    = help: assign this const to a local or static variable, and use the variable here
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/others.rs:72:5
+   |
+LL |     let _ = &ATOMIC_TUPLE; //~ ERROR interior mutability
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: a `const` item with interior mutability should not be borrowed
   --> $DIR/others.rs:72:14
    |
@@ -95,6 +104,22 @@ LL |     let _ = ATOMIC_TUPLE.0[0]; //~ ERROR interior mutability
    |
    = help: assign this const to a local or static variable, and use the variable here
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/others.rs:83:5
+   |
+LL |     let _ = ATOMIC_TUPLE.1.into_iter();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/others.rs:85:5
+   |
+LL |     let _ = &{ ATOMIC_TUPLE };
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: a `const` item with interior mutability should not be borrowed
   --> $DIR/others.rs:87:5
    |
@@ -111,5 +136,5 @@ LL |     assert_eq!(CELL.get(), 6); //~ ERROR interior mutability
    |
    = help: assign this const to a local or static variable, and use the variable here
 
-error: aborting due to 14 previous errors
+error: aborting due to 17 previous errors
 

tests/ui/box_vec.stderr

@@ -1,3 +1,16 @@
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/box_vec.rs:7:9
+   |
+LL |         let _: Box<$x> = Box::new($init);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+...
+LL |     boxit!(Vec::new(), Vec<u8>);
+   |     ---------------------------- in this macro invocation
+   |
+   = note: `-D clippy::let-underscore-drop` implied by `-D warnings`
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
 error: you seem to be trying to use `Box<Vec<T>>`. Consider using just `Vec<T>`
   --> $DIR/box_vec.rs:14:18
    |
@@ -7,5 +20,5 @@ LL | pub fn test(foo: Box<Vec<bool>>) {
    = note: `-D clippy::box-vec` implied by `-D warnings`
    = help: `Vec<T>` is already on the heap, `Box<Vec<T>>` makes an extra allocation.
 
-error: aborting due to previous error
+error: aborting due to 2 previous errors
 

tests/ui/crashes/ice-4968.stderr

@@ -0,0 +1,11 @@
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/ice-4968.rs:16:9
+   |
+LL |         let _: Vec<ManuallyDrop<T::Assoc>> = mem::transmute(slice);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
+error: aborting due to previous error
+

tests/ui/crashes/ice-5223.stderr

@@ -0,0 +1,11 @@
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/ice-5223.rs:14:9
+   |
+LL |         let _ = self.arr.iter().cloned().collect::<Vec<_>>();
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
+error: aborting due to previous error
+

tests/ui/escape_analysis.stderr

@@ -12,5 +12,26 @@ error: local variable doesn't need to be boxed here
 LL | pub fn new(_needs_name: Box<PeekableSeekable<&()>>) -> () {}
    |            ^^^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/escape_analysis.rs:166:9
+   |
+LL | /         let _ = move || {
+LL | |             consume(x);
+LL | |         };
+   | |__________^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/escape_analysis.rs:172:9
+   |
+LL | /         let _ = || {
+LL | |             borrow(&x);
+LL | |         };
+   | |__________^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
+error: aborting due to 4 previous errors
 

tests/ui/eta.stderr

@@ -64,6 +64,15 @@ error: redundant closure found
 LL |     let e: std::vec::Vec<char> = vec!['a', 'b', 'c'].iter().map(|c| c.to_ascii_uppercase()).collect();
    |                                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove closure as shown: `char::to_ascii_uppercase`
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/eta.rs:107:5
+   |
+LL |     let _: Vec<_> = arr.iter().map(|x| x.map_err(|e| some.take().unwrap()(e))).collect();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: redundant closure found
   --> $DIR/eta.rs:172:27
    |
@@ -76,5 +85,13 @@ error: redundant closure found
 LL |     let a = Some(1u8).map(|a| closure(a));
    |                           ^^^^^^^^^^^^^^ help: remove closure as shown: `closure`
 
-error: aborting due to 12 previous errors
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/eta.rs:203:5
+   |
+LL |     let _ = [Bar].iter().map(|s| s.to_string()).collect::<Vec<_>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
+error: aborting due to 14 previous errors
 

tests/ui/filter_methods.stderr

@@ -1,3 +1,12 @@
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/filter_methods.rs:5:5
+   |
+LL |     let _: Vec<_> = vec![5; 6].into_iter().filter(|&x| x == 0).map(|x| x * 2).collect();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::let-underscore-drop` implied by `-D warnings`
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: called `filter(..).map(..)` on an `Iterator`
   --> $DIR/filter_methods.rs:5:21
    |
@@ -7,6 +16,18 @@ LL |     let _: Vec<_> = vec![5; 6].into_iter().filter(|&x| x == 0).map(|x| x *
    = note: `-D clippy::filter-map` implied by `-D warnings`
    = help: this is more succinctly expressed by calling `.filter_map(..)` instead
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/filter_methods.rs:7:5
+   |
+LL | /     let _: Vec<_> = vec![5_i8; 6]
+LL | |         .into_iter()
+LL | |         .filter(|&x| x == 0)
+LL | |         .flat_map(|x| x.checked_mul(2))
+LL | |         .collect();
+   | |___________________^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: called `filter(..).flat_map(..)` on an `Iterator`
   --> $DIR/filter_methods.rs:7:21
    |
@@ -19,6 +40,18 @@ LL | |         .flat_map(|x| x.checked_mul(2))
    |
    = help: this is more succinctly expressed by calling `.flat_map(..)` and filtering by returning `iter::empty()`
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/filter_methods.rs:13:5
+   |
+LL | /     let _: Vec<_> = vec![5_i8; 6]
+LL | |         .into_iter()
+LL | |         .filter_map(|x| x.checked_mul(2))
+LL | |         .flat_map(|x| x.checked_mul(2))
+LL | |         .collect();
+   | |___________________^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: called `filter_map(..).flat_map(..)` on an `Iterator`
   --> $DIR/filter_methods.rs:13:21
    |
@@ -31,6 +64,18 @@ LL | |         .flat_map(|x| x.checked_mul(2))
    |
    = help: this is more succinctly expressed by calling `.flat_map(..)` and filtering by returning `iter::empty()`
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/filter_methods.rs:19:5
+   |
+LL | /     let _: Vec<_> = vec![5_i8; 6]
+LL | |         .into_iter()
+LL | |         .filter_map(|x| x.checked_mul(2))
+LL | |         .map(|x| x.checked_mul(2))
+LL | |         .collect();
+   | |___________________^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: called `filter_map(..).map(..)` on an `Iterator`
   --> $DIR/filter_methods.rs:19:21
    |
@@ -43,5 +88,5 @@ LL | |         .map(|x| x.checked_mul(2))
    |
    = help: this is more succinctly expressed by only calling `.filter_map(..)` instead
 
-error: aborting due to 4 previous errors
+error: aborting due to 8 previous errors
 

tests/ui/get_unwrap.stderr

@@ -70,17 +70,34 @@ error: called `.get_mut().unwrap()` on a VecDeque. Using `[]` is more clear and
 LL |         *some_vecdeque.get_mut(0).unwrap() = 1;
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `some_vecdeque[0]`
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/get_unwrap.rs:59:9
+   |
+LL |         let _ = some_vec.get(0..1).unwrap().to_vec();
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: called `.get().unwrap()` on a Vec. Using `[]` is more clear and more concise
   --> $DIR/get_unwrap.rs:59:17
    |
 LL |         let _ = some_vec.get(0..1).unwrap().to_vec();
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `some_vec[0..1]`
 
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/get_unwrap.rs:60:9
+   |
+LL |         let _ = some_vec.get_mut(0..1).unwrap().to_vec();
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: called `.get_mut().unwrap()` on a Vec. Using `[]` is more clear and more concise
   --> $DIR/get_unwrap.rs:60:17
    |
 LL |         let _ = some_vec.get_mut(0..1).unwrap().to_vec();
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `some_vec[0..1]`
 
-error: aborting due to 13 previous errors
+error: aborting due to 15 previous errors
 

tests/ui/into_iter_on_ref.stderr

@@ -1,3 +1,12 @@
+error: non-binding let on a type that implements `Drop`
+  --> $DIR/into_iter_on_ref.rs:13:5
+   |
+LL |     let _ = vec![1, 2, 3].into_iter();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[deny(clippy::let_underscore_drop)]` on by default
+   = help: consider using an underscore-prefixed named binding or dropping explicitly with `std::mem::drop`
+
 error: this `.into_iter()` call is equivalent to `.iter()` and will not consume the `Vec`
   --> $DIR/into_iter_on_ref.rs:14:30
    |
@@ -162,5 +171,5 @@ error: this `.into_iter()` call is equivalent to `.iter()` and will not consume
 LL |     let _ = (&[1, 2, 3]).into_iter().next(); //~ WARN equivalent to .iter()
    |                          ^^^^^^^^^ help: call directly: `iter`
 
-error: aborting due to 27 previous errors
+error: aborting due to 28 previous errors