Move needless_pass_by_ref_mut: suspicious -> nursery

clippy_lints/src/needless_pass_by_ref_mut.rs

@@ -49,7 +49,7 @@ declare_clippy_lint! {
     /// ```
     #[clippy::version = "1.72.0"]
     pub NEEDLESS_PASS_BY_REF_MUT,
-    suspicious,
+    nursery,
     "using a `&mut` argument when it's not mutated"
 }
 

tests/ui/infinite_loop.rs

@@ -7,8 +7,6 @@ fn fn_constref(i: &i32) -> i32 {
     unimplemented!()
 }
 fn fn_mutref(i: &mut i32) {
-    //~^ ERROR: this argument is a mutable reference, but not used mutably
-    //~| NOTE: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
     unimplemented!()
 }
 fn fooi() -> i32 {

tests/ui/infinite_loop.stderr

@@ -1,5 +1,5 @@
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:24:11
+  --> $DIR/infinite_loop.rs:22:11
    |
 LL |     while y < 10 {
    |           ^^^^^^
@@ -8,71 +8,71 @@ LL |     while y < 10 {
    = note: `#[deny(clippy::while_immutable_condition)]` on by default
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:31:11
+  --> $DIR/infinite_loop.rs:29:11
    |
 LL |     while y < 10 && x < 3 {
    |           ^^^^^^^^^^^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:40:11
+  --> $DIR/infinite_loop.rs:38:11
    |
 LL |     while !cond {
    |           ^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:86:11
+  --> $DIR/infinite_loop.rs:84:11
    |
 LL |     while i < 3 {
    |           ^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:93:11
+  --> $DIR/infinite_loop.rs:91:11
    |
 LL |     while i < 3 && j > 0 {
    |           ^^^^^^^^^^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:99:11
+  --> $DIR/infinite_loop.rs:97:11
    |
 LL |     while i < 3 {
    |           ^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:116:11
+  --> $DIR/infinite_loop.rs:114:11
    |
 LL |     while i < 3 {
    |           ^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:123:11
+  --> $DIR/infinite_loop.rs:121:11
    |
 LL |     while i < 3 {
    |           ^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:191:15
+  --> $DIR/infinite_loop.rs:189:15
    |
 LL |         while self.count < n {
    |               ^^^^^^^^^^^^^^
    |
    = note: this may lead to an infinite or to a never running loop
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:201:11
+  --> $DIR/infinite_loop.rs:199:11
    |
 LL |     while y < 10 {
    |           ^^^^^^
@@ -82,7 +82,7 @@ LL |     while y < 10 {
    = help: rewrite it as `if cond { loop { } }`
 
 error: variables in the condition are not mutated in the loop body
-  --> $DIR/infinite_loop.rs:210:11
+  --> $DIR/infinite_loop.rs:208:11
    |
 LL |     while y < 10 {
    |           ^^^^^^
@@ -91,14 +91,5 @@ LL |     while y < 10 {
    = note: this loop contains `return`s or `break`s
    = help: rewrite it as `if cond { loop { } }`
 
-error: this argument is a mutable reference, but not used mutably
-  --> $DIR/infinite_loop.rs:9:17
-   |
-LL | fn fn_mutref(i: &mut i32) {
-   |                 ^^^^^^^^ help: consider changing to: `&i32`
-   |
-   = note: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
-   = help: to override `-D warnings` add `#[allow(clippy::needless_pass_by_ref_mut)]`
-
-error: aborting due to 12 previous errors
+error: aborting due to 11 previous errors
 

tests/ui/let_underscore_future.rs

@@ -9,8 +9,6 @@ fn custom() -> impl Future<Output = ()> {
 }
 
 fn do_something_to_future(future: &mut impl Future<Output = ()>) {}
-//~^ ERROR: this argument is a mutable reference, but not used mutably
-//~| NOTE: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
 
 fn main() {
     let _ = some_async_fn();

tests/ui/let_underscore_future.stderr

@@ -1,5 +1,5 @@
 error: non-binding `let` on a future
-  --> $DIR/let_underscore_future.rs:16:5
+  --> $DIR/let_underscore_future.rs:14:5
    |
 LL |     let _ = some_async_fn();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -9,29 +9,20 @@ LL |     let _ = some_async_fn();
    = help: to override `-D warnings` add `#[allow(clippy::let_underscore_future)]`
 
 error: non-binding `let` on a future
-  --> $DIR/let_underscore_future.rs:18:5
+  --> $DIR/let_underscore_future.rs:16:5
    |
 LL |     let _ = custom();
    |     ^^^^^^^^^^^^^^^^^
    |
    = help: consider awaiting the future or dropping explicitly with `std::mem::drop`
 
 error: non-binding `let` on a future
-  --> $DIR/let_underscore_future.rs:23:5
+  --> $DIR/let_underscore_future.rs:21:5
    |
 LL |     let _ = future;
    |     ^^^^^^^^^^^^^^^
    |
    = help: consider awaiting the future or dropping explicitly with `std::mem::drop`
 
-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`
-   = help: to override `-D warnings` add `#[allow(clippy::needless_pass_by_ref_mut)]`
-
-error: aborting due to 4 previous errors
+error: aborting due to 3 previous errors
 

tests/ui/mut_key.rs

@@ -32,8 +32,6 @@ fn should_not_take_this_arg(m: &mut HashMap<Key, usize>, _n: usize) -> HashSet<K
     //~^ ERROR: mutable key type
     //~| NOTE: `-D clippy::mutable-key-type` implied by `-D warnings`
     //~| ERROR: mutable key type
-    //~| ERROR: this argument is a mutable reference, but not used mutably
-    //~| NOTE: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
     let _other: HashMap<Key, bool> = HashMap::new();
     //~^ ERROR: mutable key type
     m.keys().cloned().collect()

tests/ui/mut_key.stderr

@@ -14,103 +14,94 @@ LL | fn should_not_take_this_arg(m: &mut HashMap<Key, usize>, _n: usize) -> Hash
    |                                                                        ^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:37:5
+  --> $DIR/mut_key.rs:35:5
    |
 LL |     let _other: HashMap<Key, bool> = HashMap::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:65:22
+  --> $DIR/mut_key.rs:63:22
    |
 LL | fn tuples_bad<U>(_m: &mut HashMap<(Key, U), bool>) {}
    |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:78:5
+  --> $DIR/mut_key.rs:76:5
    |
 LL |     let _map = HashMap::<Cell<usize>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:80:5
+  --> $DIR/mut_key.rs:78:5
    |
 LL |     let _map = HashMap::<&mut Cell<usize>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:82:5
+  --> $DIR/mut_key.rs:80:5
    |
 LL |     let _map = HashMap::<&mut usize, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:85:5
+  --> $DIR/mut_key.rs:83:5
    |
 LL |     let _map = HashMap::<Vec<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:87:5
+  --> $DIR/mut_key.rs:85:5
    |
 LL |     let _map = HashMap::<BTreeMap<Cell<usize>, ()>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:89:5
+  --> $DIR/mut_key.rs:87:5
    |
 LL |     let _map = HashMap::<BTreeMap<(), Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:91:5
+  --> $DIR/mut_key.rs:89:5
    |
 LL |     let _map = HashMap::<BTreeSet<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:93:5
+  --> $DIR/mut_key.rs:91:5
    |
 LL |     let _map = HashMap::<Option<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:95:5
+  --> $DIR/mut_key.rs:93:5
    |
 LL |     let _map = HashMap::<Option<Vec<Cell<usize>>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:97:5
+  --> $DIR/mut_key.rs:95:5
    |
 LL |     let _map = HashMap::<Result<&mut usize, ()>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:100:5
+  --> $DIR/mut_key.rs:98:5
    |
 LL |     let _map = HashMap::<Box<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:102:5
+  --> $DIR/mut_key.rs:100:5
    |
 LL |     let _map = HashMap::<Rc<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: mutable key type
-  --> $DIR/mut_key.rs:104:5
+  --> $DIR/mut_key.rs:102:5
    |
 LL |     let _map = HashMap::<Arc<Cell<usize>>, usize>::new();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: this argument is a mutable reference, but not used mutably
-  --> $DIR/mut_key.rs:31:32
-   |
-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`
-   = help: to override `-D warnings` add `#[allow(clippy::needless_pass_by_ref_mut)]`
-
-error: aborting due to 18 previous errors
+error: aborting due to 17 previous errors
 

tests/ui/mut_reference.rs

@@ -22,8 +22,6 @@ impl MyStruct {
     fn takes_an_immutable_reference(&self, a: &i32) {}
 
     fn takes_a_mutable_reference(&self, a: &mut i32) {}
-    //~^ ERROR: this argument is a mutable reference, but not used mutably
-    //~| NOTE: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
 }
 
 #[warn(clippy::unnecessary_mut_passed)]

tests/ui/mut_reference.stderr

@@ -1,5 +1,5 @@
 error: the function `takes_an_immutable_reference` doesn't need a mutable reference
-  --> $DIR/mut_reference.rs:32:34
+  --> $DIR/mut_reference.rs:30:34
    |
 LL |     takes_an_immutable_reference(&mut 42);
    |                                  ^^^^^^^
@@ -8,25 +8,16 @@ LL |     takes_an_immutable_reference(&mut 42);
    = help: to override `-D warnings` add `#[allow(clippy::unnecessary_mut_passed)]`
 
 error: the function `as_ptr` doesn't need a mutable reference
-  --> $DIR/mut_reference.rs:36:12
+  --> $DIR/mut_reference.rs:34:12
    |
 LL |     as_ptr(&mut 42);
    |            ^^^^^^^
 
 error: the method `takes_an_immutable_reference` doesn't need a mutable reference
-  --> $DIR/mut_reference.rs:41:44
+  --> $DIR/mut_reference.rs:39:44
    |
 LL |     my_struct.takes_an_immutable_reference(&mut 42);
    |                                            ^^^^^^^
 
-error: this argument is a mutable reference, but not used mutably
-  --> $DIR/mut_reference.rs:24:44
-   |
-LL |     fn takes_a_mutable_reference(&self, a: &mut i32) {}
-   |                                            ^^^^^^^^ help: consider changing to: `&i32`
-   |
-   = note: `-D clippy::needless-pass-by-ref-mut` implied by `-D warnings`
-   = help: to override `-D warnings` add `#[allow(clippy::needless_pass_by_ref_mut)]`
-
-error: aborting due to 4 previous errors
+error: aborting due to 3 previous errors
 

tests/ui/needless_pass_by_ref_mut.rs

@@ -1,4 +1,5 @@
 #![allow(clippy::if_same_then_else, clippy::no_effect, clippy::redundant_closure_call)]
+#![warn(clippy::needless_pass_by_ref_mut)]
 #![feature(lint_reasons)]
 //@no-rustfix
 use std::ptr::NonNull;