Update UI tests with new needless_pass_by_ref_mut lint

tests/ui-toml/toml_trivially_copy/test.rs

@@ -2,6 +2,7 @@
 //@normalize-stderr-test: "\(limit: \d+ byte\)" -> "(limit: N byte)"
 
 #![deny(clippy::trivially_copy_pass_by_ref)]
+#![allow(clippy::needless_pass_by_ref_mut)]
 
 #[derive(Copy, Clone)]
 struct Foo(u8);

tests/ui-toml/toml_trivially_copy/test.stderr

@@ -1,5 +1,5 @@
 error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
-  --> $DIR/test.rs:14:11
+  --> $DIR/test.rs:15:11
    |
 LL | fn bad(x: &u16, y: &Foo) {}
    |           ^^^^ help: consider passing by value instead: `u16`
@@ -11,7 +11,7 @@ LL | #![deny(clippy::trivially_copy_pass_by_ref)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
-  --> $DIR/test.rs:14:20
+  --> $DIR/test.rs:15:20
    |
 LL | fn bad(x: &u16, y: &Foo) {}
    |                    ^^^^ help: consider passing by value instead: `Foo`

tests/ui/borrow_box.rs

@@ -1,6 +1,10 @@
 #![deny(clippy::borrowed_box)]
 #![allow(dead_code, unused_variables)]
-#![allow(clippy::uninlined_format_args, clippy::disallowed_names)]
+#![allow(
+    clippy::uninlined_format_args,
+    clippy::disallowed_names,
+    clippy::needless_pass_by_ref_mut
+)]
 
 use std::fmt::Display;
 

tests/ui/borrow_box.stderr

@@ -1,5 +1,5 @@
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:20:14
+  --> $DIR/borrow_box.rs:24:14
    |
 LL |     let foo: &Box<bool>;
    |              ^^^^^^^^^^ help: try: `&bool`
@@ -11,55 +11,55 @@ LL | #![deny(clippy::borrowed_box)]
    |         ^^^^^^^^^^^^^^^^^^^^
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:24:10
+  --> $DIR/borrow_box.rs:28:10
    |
 LL |     foo: &'a Box<bool>,
    |          ^^^^^^^^^^^^^ help: try: `&'a bool`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:28:17
+  --> $DIR/borrow_box.rs:32:17
    |
 LL |     fn test4(a: &Box<bool>);
    |                 ^^^^^^^^^^ help: try: `&bool`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:94:25
+  --> $DIR/borrow_box.rs:98:25
    |
 LL | pub fn test14(_display: &Box<dyn Display>) {}
    |                         ^^^^^^^^^^^^^^^^^ help: try: `&dyn Display`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:95:25
+  --> $DIR/borrow_box.rs:99:25
    |
 LL | pub fn test15(_display: &Box<dyn Display + Send>) {}
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&(dyn Display + Send)`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:96:29
+  --> $DIR/borrow_box.rs:100:29
    |
 LL | pub fn test16<'a>(_display: &'a Box<dyn Display + 'a>) {}
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&'a (dyn Display + 'a)`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:98:25
+  --> $DIR/borrow_box.rs:102:25
    |
 LL | pub fn test17(_display: &Box<impl Display>) {}
    |                         ^^^^^^^^^^^^^^^^^^ help: try: `&impl Display`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:99:25
+  --> $DIR/borrow_box.rs:103:25
    |
 LL | pub fn test18(_display: &Box<impl Display + Send>) {}
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&(impl Display + Send)`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:100:29
+  --> $DIR/borrow_box.rs:104:29
    |
 LL | pub fn test19<'a>(_display: &'a Box<impl Display + 'a>) {}
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&'a (impl Display + 'a)`
 
 error: you seem to be trying to use `&Box<T>`. Consider using just `&T`
-  --> $DIR/borrow_box.rs:105:25
+  --> $DIR/borrow_box.rs:109:25
    |
 LL | pub fn test20(_display: &Box<(dyn Display + Send)>) {}
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&(dyn Display + Send)`

tests/ui/infinite_loop.stderr

@@ -1,3 +1,11 @@
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/infinite_loop.rs:7:17
+   |
+LL | fn fn_mutref(i: &mut i32) {
+   |                 ^^^^^^^^ help: consider changing to: `&i32`
+   |
+   = note: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
+
 error: variables in the condition are not mutated in the loop body
   --> $DIR/infinite_loop.rs:20:11
    |
@@ -91,5 +99,5 @@ LL |     while y < 10 {
    = note: this loop contains `return`s or `break`s
    = help: rewrite it as `if cond { loop { } }`
 
-error: aborting due to 11 previous errors
+error: aborting due to 12 previous errors
 

tests/ui/let_underscore_future.stderr

@@ -1,3 +1,11 @@
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/let_underscore_future.rs:11:35
+   |
+LL | fn do_something_to_future(future: &mut impl Future<Output = ()>) {}
+   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&impl Future<Output = ()>`
+   |
+   = note: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
+
 error: non-binding `let` on a future
   --> $DIR/let_underscore_future.rs:14:5
    |
@@ -23,5 +31,5 @@ LL |     let _ = future;
    |
    = help: consider awaiting the future or dropping explicitly with `std::mem::drop`
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 

tests/ui/must_use_candidates.fixed

@@ -1,6 +1,11 @@
 //@run-rustfix
 #![feature(never_type)]
-#![allow(unused_mut, unused_tuple_struct_fields, clippy::redundant_allocation)]
+#![allow(
+    unused_mut,
+    unused_tuple_struct_fields,
+    clippy::redundant_allocation,
+    clippy::needless_pass_by_ref_mut
+)]
 #![warn(clippy::must_use_candidate)]
 use std::rc::Rc;
 use std::sync::atomic::{AtomicBool, Ordering};

tests/ui/must_use_candidates.rs

@@ -1,6 +1,11 @@
 //@run-rustfix
 #![feature(never_type)]
-#![allow(unused_mut, unused_tuple_struct_fields, clippy::redundant_allocation)]
+#![allow(
+    unused_mut,
+    unused_tuple_struct_fields,
+    clippy::redundant_allocation,
+    clippy::needless_pass_by_ref_mut
+)]
 #![warn(clippy::must_use_candidate)]
 use std::rc::Rc;
 use std::sync::atomic::{AtomicBool, Ordering};

tests/ui/must_use_candidates.stderr

@@ -1,31 +1,31 @@
 error: this function could have a `#[must_use]` attribute
-  --> $DIR/must_use_candidates.rs:12:1
+  --> $DIR/must_use_candidates.rs:17:1
    |
 LL | pub fn pure(i: u8) -> u8 {
    | ^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[must_use] pub fn pure(i: u8) -> u8`
    |
    = note: `-D clippy::must-use-candidate` implied by `-D warnings`
 
 error: this method could have a `#[must_use]` attribute
-  --> $DIR/must_use_candidates.rs:17:5
+  --> $DIR/must_use_candidates.rs:22:5
    |
 LL |     pub fn inherent_pure(&self) -> u8 {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[must_use] pub fn inherent_pure(&self) -> u8`
 
 error: this function could have a `#[must_use]` attribute
-  --> $DIR/must_use_candidates.rs:48:1
+  --> $DIR/must_use_candidates.rs:53:1
    |
 LL | pub fn with_marker(_d: std::marker::PhantomData<&mut u32>) -> bool {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[must_use] pub fn with_marker(_d: std::marker::PhantomData<&mut u32>) -> bool`
 
 error: this function could have a `#[must_use]` attribute
-  --> $DIR/must_use_candidates.rs:60:1
+  --> $DIR/must_use_candidates.rs:65:1
    |
 LL | pub fn rcd(_x: Rc<u32>) -> bool {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[must_use] pub fn rcd(_x: Rc<u32>) -> bool`
 
 error: this function could have a `#[must_use]` attribute
-  --> $DIR/must_use_candidates.rs:68:1
+  --> $DIR/must_use_candidates.rs:73:1
    |
 LL | pub fn arcd(_x: Arc<u32>) -> bool {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add the attribute: `#[must_use] pub fn arcd(_x: Arc<u32>) -> bool`

tests/ui/mut_from_ref.rs

@@ -1,4 +1,4 @@
-#![allow(unused, clippy::needless_lifetimes)]
+#![allow(unused, clippy::needless_lifetimes, clippy::needless_pass_by_ref_mut)]
 #![warn(clippy::mut_from_ref)]
 
 struct Foo;

tests/ui/mut_key.stderr

@@ -12,6 +12,14 @@ error: mutable key type
 LL | fn should_not_take_this_arg(m: &mut HashMap<Key, usize>, _n: usize) -> HashSet<Key> {
    |                                                                        ^^^^^^^^^^^^
 
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/mut_key.rs:30:32
+   |
+LL | fn should_not_take_this_arg(m: &mut HashMap<Key, usize>, _n: usize) -> HashSet<Key> {
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing to: `&HashMap<Key, usize>`
+   |
+   = note: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
+
 error: mutable key type
   --> $DIR/mut_key.rs:31:5
    |
@@ -102,5 +110,5 @@ error: mutable key type
 LL |     let _map = HashMap::<Arc<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 17 previous errors
+error: aborting due to 18 previous errors
 

tests/ui/mut_mut.rs

@@ -1,7 +1,12 @@
 //@aux-build:proc_macros.rs
 #![warn(clippy::mut_mut)]
 #![allow(unused)]
-#![allow(clippy::no_effect, clippy::uninlined_format_args, clippy::unnecessary_operation)]
+#![allow(
+    clippy::no_effect,
+    clippy::uninlined_format_args,
+    clippy::unnecessary_operation,
+    clippy::needless_pass_by_ref_mut
+)]
 
 extern crate proc_macros;
 use proc_macros::{external, inline_macros};

tests/ui/mut_mut.stderr

@@ -1,57 +1,57 @@
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:9:11
+  --> $DIR/mut_mut.rs:14:11
    |
 LL | fn fun(x: &mut &mut u32) -> bool {
    |           ^^^^^^^^^^^^^
    |
    = note: `-D clippy::mut-mut` implied by `-D warnings`
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:26:17
+  --> $DIR/mut_mut.rs:31:17
    |
 LL |     let mut x = &mut &mut 1u32;
    |                 ^^^^^^^^^^^^^^
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:41:25
+  --> $DIR/mut_mut.rs:46:25
    |
 LL |     let mut z = inline!(&mut $(&mut 3u32));
    |                         ^
    |
    = note: this error originates in the macro `__inline_mac_fn_main` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: this expression mutably borrows a mutable reference. Consider reborrowing
-  --> $DIR/mut_mut.rs:28:21
+  --> $DIR/mut_mut.rs:33:21
    |
 LL |         let mut y = &mut x;
    |                     ^^^^^^
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:32:32
+  --> $DIR/mut_mut.rs:37:32
    |
 LL |         let y: &mut &mut u32 = &mut &mut 2;
    |                                ^^^^^^^^^^^
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:32:16
+  --> $DIR/mut_mut.rs:37:16
    |
 LL |         let y: &mut &mut u32 = &mut &mut 2;
    |                ^^^^^^^^^^^^^
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:37:37
+  --> $DIR/mut_mut.rs:42:37
    |
 LL |         let y: &mut &mut &mut u32 = &mut &mut &mut 2;
    |                                     ^^^^^^^^^^^^^^^^
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:37:16
+  --> $DIR/mut_mut.rs:42:16
    |
 LL |         let y: &mut &mut &mut u32 = &mut &mut &mut 2;
    |                ^^^^^^^^^^^^^^^^^^
 
 error: generally you want to avoid `&mut &mut _` if possible
-  --> $DIR/mut_mut.rs:37:21
+  --> $DIR/mut_mut.rs:42:21
    |
 LL |         let y: &mut &mut &mut u32 = &mut &mut &mut 2;
    |                     ^^^^^^^^^^^^^

tests/ui/mut_reference.stderr

@@ -1,3 +1,17 @@
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/mut_reference.rs:4:33
+   |
+LL | fn takes_a_mutable_reference(a: &mut i32) {}
+   |                                 ^^^^^^^^ help: consider changing to: `&i32`
+   |
+   = note: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
+
+error: this argument is a mutable reference, but not used mutably
+  --> $DIR/mut_reference.rs:11:44
+   |
+LL |     fn takes_a_mutable_reference(&self, a: &mut i32) {}
+   |                                            ^^^^^^^^ help: consider changing to: `&i32`
+
 error: the function `takes_an_immutable_reference` doesn't need a mutable reference
   --> $DIR/mut_reference.rs:17:34
    |
@@ -18,5 +32,5 @@ error: the method `takes_an_immutable_reference` doesn't need a mutable referenc
 LL |     my_struct.takes_an_immutable_reference(&mut 42);
    |                                            ^^^^^^^
 
-error: aborting due to 3 previous errors
+error: aborting due to 5 previous errors
 

tests/ui/ptr_arg.rs

@@ -3,7 +3,8 @@
     unused,
     clippy::many_single_char_names,
     clippy::needless_lifetimes,
-    clippy::redundant_clone
+    clippy::redundant_clone,
+    clippy::needless_pass_by_ref_mut
 )]
 #![warn(clippy::ptr_arg)]