1 files changed, 49 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/transmute/transmute_num_to_bytes.rs b/src/tools/clippy/clippy_lints/src/transmute/transmute_num_to_bytes.rs
new file mode 100644
index 000000000..52d193d11
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/transmute/transmute_num_to_bytes.rs
@@ -0,0 +1,49 @@
+use super::TRANSMUTE_NUM_TO_BYTES;
+use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::sugg;
+use rustc_errors::Applicability;
+use rustc_hir::Expr;
+use rustc_lint::LateContext;
+use rustc_middle::ty::{self, Ty, UintTy};
+
+/// Checks for `transmute_int_to_float` lint.
+/// Returns `true` if it's triggered, otherwise returns `false`.
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    e: &'tcx Expr<'_>,
+    from_ty: Ty<'tcx>,
+    to_ty: Ty<'tcx>,
+    arg: &'tcx Expr<'_>,
+    const_context: bool,
+) -> bool {
+    match (&from_ty.kind(), &to_ty.kind()) {
+        (ty::Int(_) | ty::Uint(_) | ty::Float(_), ty::Array(arr_ty, _)) => {
+            if !matches!(arr_ty.kind(), ty::Uint(UintTy::U8)) {
+                return false;
+            }
+            if matches!(from_ty.kind(), ty::Float(_)) && const_context {
+                // TODO: Remove when const_float_bits_conv is stabilized
+                // rust#72447
+                return false;
+            }
+
+            span_lint_and_then(
+                cx,
+                TRANSMUTE_NUM_TO_BYTES,
+                e.span,
+                &format!("transmute from a `{}` to a `{}`", from_ty, to_ty),
+                |diag| {
+                    let arg = sugg::Sugg::hir(cx, arg, "..");
+                    diag.span_suggestion(
+                        e.span,
+                        "consider using `to_ne_bytes()`",
+                        format!("{}.to_ne_bytes()", arg),
+                        Applicability::Unspecified,
+                    );
+                },
+            );
+            true
+        },
+        _ => false,
+    }
+}