feat(features): seal FeatureBits

Author: mkroening

src/features.rs

@@ -1,11 +1,12 @@
 //! Feature Bits
 
 use crate::le128;
+use crate::sealed::Sealed;
 
 /// Feature Bits
 #[doc(alias = "VIRTIO_F")]
 pub trait FeatureBits:
-    bitflags::Flags<Bits = le128> + From<F> + Into<F> + AsRef<F> + AsMut<F>
+    bitflags::Flags<Bits = le128> + From<F> + Into<F> + AsRef<F> + AsMut<F> + Sealed
 {
     /// Returns the feature that this feature requires.
     ///
@@ -238,6 +239,8 @@ impl AsMut<F> for F {
 
 impl FeatureBits for F {}
 
+impl Sealed for F {}
+
 macro_rules! feature_bits {
     (
         $(#[$outer:meta])*
@@ -332,6 +335,8 @@ macro_rules! feature_bits {
             }
         }
 
+        impl $crate::sealed::Sealed for $BitFlags {}
+
         feature_bits! {
             $($t)*
         }

src/lib.rs

@@ -109,6 +109,10 @@ pub mod pvirtq;
 pub mod virtq;
 pub mod vsock;
 
+mod sealed {
+    pub trait Sealed {}
+}
+
 pub use endian_num::{be128, be16, be32, be64, le128, le16, le32, le64, Be, Le};
 use num_enum::{FromPrimitive, IntoPrimitive, TryFromPrimitive};