Rollup merge of #69529 - matthiaskrgr:clippy_identity_conversion, r=Mark-Simulacrum

don't use .into() to convert types into identical types.

This removes redundant `.into()` calls.

example: `let s: String = format!("hello").into();`

4 files changed, 4 insertions, 5 deletions

diff --git a/src/librustc/mir/interpret/allocation.rs b/src/librustc/mir/interpret/allocation.rs
index 052603f6e5e..0d0aa8a232e 100644
--- a/src/librustc/mir/interpret/allocation.rs
+++ b/src/librustc/mir/interpret/allocation.rs
@@ -472,7 +472,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> {
         val: ScalarMaybeUndef<Tag>,
     ) -> InterpResult<'tcx> {
         let ptr_size = cx.data_layout().pointer_size;
-        self.write_scalar(cx, ptr.into(), val, ptr_size)
+        self.write_scalar(cx, ptr, val, ptr_size)
     }
 }
 
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index 3086f9b04df..6a937b87645 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -1519,7 +1519,7 @@ impl<'tcx> TerminatorKind<'tcx> {
                 values
                     .iter()
                     .map(|&u| {
-                        ty::Const::from_scalar(tcx, Scalar::from_uint(u, size).into(), switch_ty)
+                        ty::Const::from_scalar(tcx, Scalar::from_uint(u, size), switch_ty)
                             .to_string()
                             .into()
                     })
diff --git a/src/librustc/mir/tcx.rs b/src/librustc/mir/tcx.rs
index e6c7c84494c..13996a74acb 100644
--- a/src/librustc/mir/tcx.rs
+++ b/src/librustc/mir/tcx.rs
@@ -156,7 +156,7 @@ impl<'tcx> Rvalue<'tcx> {
             }
             Rvalue::AddressOf(mutability, ref place) => {
                 let place_ty = place.ty(local_decls, tcx).ty;
-                tcx.mk_ptr(ty::TypeAndMut { ty: place_ty, mutbl: mutability.into() })
+                tcx.mk_ptr(ty::TypeAndMut { ty: place_ty, mutbl: mutability })
             }
             Rvalue::Len(..) => tcx.types.usize,
             Rvalue::Cast(.., ty) => ty,
diff --git a/src/librustc/traits/mod.rs b/src/librustc/traits/mod.rs
index de2ec53e51e..b05bd26f048 100644
--- a/src/librustc/traits/mod.rs
+++ b/src/librustc/traits/mod.rs
@@ -820,8 +820,7 @@ impl ObjectSafetyViolation {
                 MethodViolationCode::UndispatchableReceiver,
                 span,
             ) => (
-                format!("consider changing method `{}`'s `self` parameter to be `&self`", name)
-                    .into(),
+                format!("consider changing method `{}`'s `self` parameter to be `&self`", name),
                 Some(("&Self".to_string(), span)),
             ),
             ObjectSafetyViolation::AssocConst(name, _)