suspicious-arithmetic-impl: make lint adhere to lint message convention

Author: matthiaskrgr

clippy_lints/src/suspicious_trait_impl.rs

@@ -98,7 +98,7 @@ impl<'tcx> LateLintPass<'tcx> for SuspiciousImpl {
                     cx,
                     SUSPICIOUS_ARITHMETIC_IMPL,
                     binop.span,
-                    &format!(r#"Suspicious use of binary operator in `{}` impl"#, impl_trait),
+                    &format!("suspicious use of binary operator in `{}` impl", impl_trait),
                 );
             }
 
@@ -135,7 +135,7 @@ impl<'tcx> LateLintPass<'tcx> for SuspiciousImpl {
                     cx,
                     SUSPICIOUS_OP_ASSIGN_IMPL,
                     binop.span,
-                    &format!(r#"Suspicious use of binary operator in `{}` impl"#, impl_trait),
+                    &format!("suspicious use of binary operator in `{}` impl", impl_trait),
                 );
             }
         }

tests/ui/suspicious_arithmetic_impl.stderr

@@ -1,20 +1,20 @@
-error: Suspicious use of binary operator in `Add` impl
+error: suspicious use of binary operator in `Add` impl
   --> $DIR/suspicious_arithmetic_impl.rs:11:20
    |
 LL |         Foo(self.0 - other.0)
    |                    ^
    |
    = note: `-D clippy::suspicious-arithmetic-impl` implied by `-D warnings`
 
-error: Suspicious use of binary operator in `AddAssign` impl
+error: suspicious use of binary operator in `AddAssign` impl
   --> $DIR/suspicious_arithmetic_impl.rs:17:23
    |
 LL |         *self = *self - other;
    |                       ^
    |
    = note: `#[deny(clippy::suspicious_op_assign_impl)]` on by default
 
-error: Suspicious use of binary operator in `MulAssign` impl
+error: suspicious use of binary operator in `MulAssign` impl
   --> $DIR/suspicious_arithmetic_impl.rs:30:16
    |
 LL |         self.0 /= other.0;