rc_mutex: fix test

tests/ui/rc_mutex.rs

@@ -1,6 +1,5 @@
 #![warn(clippy::rc_mutex)]
-#![allow(clippy::boxed_local, clippy::needless_pass_by_value)]
-#![allow(clippy::blacklisted_name, unused_variables, dead_code)]
+#![allow(clippy::blacklisted_name)]
 
 use std::rc::Rc;
 use std::sync::Mutex;
@@ -24,4 +23,12 @@ pub fn test2(foo: Rc<Mutex<MyEnum>>) {}
 
 pub fn test3(foo: Rc<Mutex<SubT<usize>>>) {}
 
-fn main() {}
+fn main() {
+    test1(Rc::new(Mutex::new(1)));
+    test2(Rc::new(Mutex::new(MyEnum::One)));
+    test3(Rc::new(Mutex::new(SubT { foo: 1 })));
+
+    let _my_struct = MyStruct {
+        foo: Rc::new(Mutex::new(1)),
+    };
+}

tests/ui/rc_mutex.stderr

@@ -1,5 +1,5 @@
 error: found `Rc<Mutex<_>>`. Consider using `Rc<RefCell<_>>` or `Arc<Mutex<_>>` instead
-  --> $DIR/rc_mutex.rs:9:10
+  --> $DIR/rc_mutex.rs:8:10
    |
 LL |     foo: Rc<Mutex<i32>>,
    |          ^^^^^^^^^^^^^^
@@ -7,19 +7,19 @@ LL |     foo: Rc<Mutex<i32>>,
    = note: `-D clippy::rc-mutex` implied by `-D warnings`
 
 error: found `Rc<Mutex<_>>`. Consider using `Rc<RefCell<_>>` or `Arc<Mutex<_>>` instead
-  --> $DIR/rc_mutex.rs:21:22
+  --> $DIR/rc_mutex.rs:20:22
    |
 LL | pub fn test1<T>(foo: Rc<Mutex<T>>) {}
    |                      ^^^^^^^^^^^^
 
 error: found `Rc<Mutex<_>>`. Consider using `Rc<RefCell<_>>` or `Arc<Mutex<_>>` instead
-  --> $DIR/rc_mutex.rs:23:19
+  --> $DIR/rc_mutex.rs:22:19
    |
 LL | pub fn test2(foo: Rc<Mutex<MyEnum>>) {}
    |                   ^^^^^^^^^^^^^^^^^
 
 error: found `Rc<Mutex<_>>`. Consider using `Rc<RefCell<_>>` or `Arc<Mutex<_>>` instead
-  --> $DIR/rc_mutex.rs:25:19
+  --> $DIR/rc_mutex.rs:24:19
    |
 LL | pub fn test3(foo: Rc<Mutex<SubT<usize>>>) {}
    |                   ^^^^^^^^^^^^^^^^^^^^^^