Minor cleanup on transmute lints

Author: Jarcho

clippy_lints/src/transmute/mod.rs

@@ -372,10 +372,9 @@ declare_lint_pass!(Transmute => [
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Transmute {
-    #[allow(clippy::similar_names, clippy::too_many_lines)]
     fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
         if_chain! {
-            if let ExprKind::Call(path_expr, args) = e.kind;
+            if let ExprKind::Call(path_expr, [arg]) = e.kind;
             if let ExprKind::Path(ref qpath) = path_expr.kind;
             if let Some(def_id) = cx.qpath_res(qpath, path_expr.hir_id).opt_def_id();
             if cx.tcx.is_diagnostic_item(sym::transmute, def_id);
@@ -385,28 +384,28 @@ impl<'tcx> LateLintPass<'tcx> for Transmute {
                 // And see https://github.com/rust-lang/rust/issues/51911 for dereferencing raw pointers.
                 let const_context = in_constant(cx, e.hir_id);
 
-                let from_ty = cx.typeck_results().expr_ty(&args[0]);
+                let from_ty = cx.typeck_results().expr_ty(arg);
                 let to_ty = cx.typeck_results().expr_ty(e);
 
                 // If useless_transmute is triggered, the other lints can be skipped.
-                if useless_transmute::check(cx, e, from_ty, to_ty, args) {
+                if useless_transmute::check(cx, e, from_ty, to_ty, arg) {
                     return;
                 }
 
-                let mut linted = wrong_transmute::check(cx, e, from_ty, to_ty);
-                linted |= crosspointer_transmute::check(cx, e, from_ty, to_ty);
-                linted |= transmute_ptr_to_ref::check(cx, e, from_ty, to_ty, args, qpath);
-                linted |= transmute_int_to_char::check(cx, e, from_ty, to_ty, args);
-                linted |= transmute_ref_to_ref::check(cx, e, from_ty, to_ty, args, const_context);
-                linted |= transmute_ptr_to_ptr::check(cx, e, from_ty, to_ty, args);
-                linted |= transmute_int_to_bool::check(cx, e, from_ty, to_ty, args);
-                linted |= transmute_int_to_float::check(cx, e, from_ty, to_ty, args, const_context);
-                linted |= transmute_float_to_int::check(cx, e, from_ty, to_ty, args, const_context);
-                linted |= transmute_num_to_bytes::check(cx, e, from_ty, to_ty, args, const_context);
-                linted |= unsound_collection_transmute::check(cx, e, from_ty, to_ty);
+                let linted = wrong_transmute::check(cx, e, from_ty, to_ty)
+                    | crosspointer_transmute::check(cx, e, from_ty, to_ty)
+                    | transmute_ptr_to_ref::check(cx, e, from_ty, to_ty, arg, qpath)
+                    | transmute_int_to_char::check(cx, e, from_ty, to_ty, arg)
+                    | transmute_ref_to_ref::check(cx, e, from_ty, to_ty, arg, const_context)
+                    | transmute_ptr_to_ptr::check(cx, e, from_ty, to_ty, arg)
+                    | transmute_int_to_bool::check(cx, e, from_ty, to_ty, arg)
+                    | transmute_int_to_float::check(cx, e, from_ty, to_ty, arg, const_context)
+                    | transmute_float_to_int::check(cx, e, from_ty, to_ty, arg, const_context)
+                    | transmute_num_to_bytes::check(cx, e, from_ty, to_ty, arg, const_context)
+                    | unsound_collection_transmute::check(cx, e, from_ty, to_ty);
 
                 if !linted {
-                    transmutes_expressible_as_ptr_casts::check(cx, e, from_ty, to_ty, args);
+                    transmutes_expressible_as_ptr_casts::check(cx, e, from_ty, to_ty, arg);
                 }
             }
         }

clippy_lints/src/transmute/transmute_float_to_int.rs

@@ -15,7 +15,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
     const_context: bool,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
@@ -26,7 +26,7 @@ pub(super) fn check<'tcx>(
                 e.span,
                 &format!("transmute from a `{}` to a `{}`", from_ty, to_ty),
                 |diag| {
-                    let mut expr = &args[0];
+                    let mut expr = arg;
                     let mut arg = sugg::Sugg::hir(cx, expr, "..");
 
                     if let ExprKind::Unary(UnOp::Neg, inner_expr) = &expr.kind {

clippy_lints/src/transmute/transmute_int_to_bool.rs

@@ -15,7 +15,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
         (ty::Int(ty::IntTy::I8) | ty::Uint(ty::UintTy::U8), ty::Bool) => {
@@ -25,7 +25,7 @@ pub(super) fn check<'tcx>(
                 e.span,
                 &format!("transmute from a `{}` to a `bool`", from_ty),
                 |diag| {
-                    let arg = sugg::Sugg::hir(cx, &args[0], "..");
+                    let arg = sugg::Sugg::hir(cx, arg, "..");
                     let zero = sugg::Sugg::NonParen(Cow::from("0"));
                     diag.span_suggestion(
                         e.span,

clippy_lints/src/transmute/transmute_int_to_char.rs

@@ -14,7 +14,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
         (ty::Int(ty::IntTy::I32) | ty::Uint(ty::UintTy::U32), &ty::Char) => {
@@ -24,7 +24,7 @@ pub(super) fn check<'tcx>(
                 e.span,
                 &format!("transmute from a `{}` to a `char`", from_ty),
                 |diag| {
-                    let arg = sugg::Sugg::hir(cx, &args[0], "..");
+                    let arg = sugg::Sugg::hir(cx, arg, "..");
                     let arg = if let ty::Int(_) = from_ty.kind() {
                         arg.as_ty(ast::UintTy::U32.name_str())
                     } else {

clippy_lints/src/transmute/transmute_int_to_float.rs

@@ -13,7 +13,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
     const_context: bool,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
@@ -24,7 +24,7 @@ pub(super) fn check<'tcx>(
                 e.span,
                 &format!("transmute from a `{}` to a `{}`", from_ty, to_ty),
                 |diag| {
-                    let arg = sugg::Sugg::hir(cx, &args[0], "..");
+                    let arg = sugg::Sugg::hir(cx, arg, "..");
                     let arg = if let ty::Int(int_ty) = from_ty.kind() {
                         arg.as_ty(format!(
                             "u{}",

clippy_lints/src/transmute/transmute_num_to_bytes.rs

@@ -13,7 +13,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
     const_context: bool,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
@@ -33,7 +33,7 @@ pub(super) fn check<'tcx>(
                 e.span,
                 &format!("transmute from a `{}` to a `{}`", from_ty, to_ty),
                 |diag| {
-                    let arg = sugg::Sugg::hir(cx, &args[0], "..");
+                    let arg = sugg::Sugg::hir(cx, arg, "..");
                     diag.span_suggestion(
                         e.span,
                         "consider using `to_ne_bytes()`",

clippy_lints/src/transmute/transmute_ptr_to_ptr.rs

@@ -13,7 +13,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
         (ty::RawPtr(_), ty::RawPtr(to_ty)) => {
@@ -23,7 +23,7 @@ pub(super) fn check<'tcx>(
                 e.span,
                 "transmute from a pointer to a pointer",
                 |diag| {
-                    if let Some(arg) = sugg::Sugg::hir_opt(cx, &args[0]) {
+                    if let Some(arg) = sugg::Sugg::hir_opt(cx, arg) {
                         let sugg = arg.as_ty(cx.tcx.mk_ptr(*to_ty));
                         diag.span_suggestion(e.span, "try", sugg.to_string(), Applicability::Unspecified);
                     }

clippy_lints/src/transmute/transmute_ptr_to_ref.rs

@@ -14,7 +14,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
     qpath: &'tcx QPath<'_>,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
@@ -28,7 +28,7 @@ pub(super) fn check<'tcx>(
                     from_ty, to_ty
                 ),
                 |diag| {
-                    let arg = sugg::Sugg::hir(cx, &args[0], "..");
+                    let arg = sugg::Sugg::hir(cx, arg, "..");
                     let (deref, cast) = if *mutbl == Mutability::Mut {
                         ("&mut *", "*mut")
                     } else {

clippy_lints/src/transmute/transmute_ref_to_ref.rs

@@ -15,7 +15,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
     const_context: bool,
 ) -> bool {
     let mut triggered = false;
@@ -41,7 +41,7 @@ pub(super) fn check<'tcx>(
                     format!(
                         "std::str::from_utf8{}({}).unwrap()",
                         postfix,
-                        snippet(cx, args[0].span, ".."),
+                        snippet(cx, arg.span, ".."),
                     ),
                     Applicability::Unspecified,
                 );
@@ -54,7 +54,7 @@ pub(super) fn check<'tcx>(
                         TRANSMUTE_PTR_TO_PTR,
                         e.span,
                         "transmute from a reference to a reference",
-                        |diag| if let Some(arg) = sugg::Sugg::hir_opt(cx, &args[0]) {
+                        |diag| if let Some(arg) = sugg::Sugg::hir_opt(cx, arg) {
                             let ty_from_and_mut = ty::TypeAndMut {
                                 ty: ty_from,
                                 mutbl: *from_mutbl

clippy_lints/src/transmute/transmutes_expressible_as_ptr_casts.rs

@@ -14,7 +14,7 @@ pub(super) fn check<'tcx>(
     e: &'tcx Expr<'_>,
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
-    args: &'tcx [Expr<'_>],
+    arg: &'tcx Expr<'_>,
 ) -> bool {
     if can_be_expressed_as_pointer_cast(cx, e, from_ty, to_ty) {
         span_lint_and_then(
@@ -26,7 +26,7 @@ pub(super) fn check<'tcx>(
                 from_ty, to_ty
             ),
             |diag| {
-                if let Some(arg) = sugg::Sugg::hir_opt(cx, &args[0]) {
+                if let Some(arg) = sugg::Sugg::hir_opt(cx, arg) {
                     let sugg = arg.as_ty(&to_ty.to_string()).to_string();
                     diag.span_suggestion(e.span, "try", sugg, Applicability::MachineApplicable);
                 }