1 files changed, 108 insertions, 0 deletions
diff --git a/third_party/rust/generic-array/src/impl_serde.rs b/third_party/rust/generic-array/src/impl_serde.rs
new file mode 100644
index 0000000000..49c095a5de
--- /dev/null
+++ b/third_party/rust/generic-array/src/impl_serde.rs
@@ -0,0 +1,108 @@
+//! Serde serialization/deserialization implementation
+
+use core::fmt;
+use core::marker::PhantomData;
+use serde::de::{self, SeqAccess, Visitor};
+use serde::{ser::SerializeTuple, Deserialize, Deserializer, Serialize, Serializer};
+use {ArrayLength, GenericArray};
+
+impl<T, N> Serialize for GenericArray<T, N>
+where
+    T: Serialize,
+    N: ArrayLength<T>,
+{
+    #[inline]
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let mut tup = serializer.serialize_tuple(N::USIZE)?;
+        for el in self {
+            tup.serialize_element(el)?;
+        }
+
+        tup.end()
+    }
+}
+
+struct GAVisitor<T, N> {
+    _t: PhantomData<T>,
+    _n: PhantomData<N>,
+}
+
+impl<'de, T, N> Visitor<'de> for GAVisitor<T, N>
+where
+    T: Deserialize<'de> + Default,
+    N: ArrayLength<T>,
+{
+    type Value = GenericArray<T, N>;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("struct GenericArray")
+    }
+
+    fn visit_seq<A>(self, mut seq: A) -> Result<GenericArray<T, N>, A::Error>
+    where
+        A: SeqAccess<'de>,
+    {
+        let mut result = GenericArray::default();
+        for i in 0..N::USIZE {
+            result[i] = seq
+                .next_element()?
+                .ok_or_else(|| de::Error::invalid_length(i, &self))?;
+        }
+        Ok(result)
+    }
+}
+
+impl<'de, T, N> Deserialize<'de> for GenericArray<T, N>
+where
+    T: Deserialize<'de> + Default,
+    N: ArrayLength<T>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<GenericArray<T, N>, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let visitor = GAVisitor {
+            _t: PhantomData,
+            _n: PhantomData,
+        };
+        deserializer.deserialize_tuple(N::USIZE, visitor)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use bincode;
+    use typenum;
+
+    #[test]
+    fn test_serialize() {
+        let array = GenericArray::<u8, typenum::U2>::default();
+        let serialized = bincode::serialize(&array);
+        assert!(serialized.is_ok());
+    }
+
+    #[test]
+    fn test_deserialize() {
+        let mut array = GenericArray::<u8, typenum::U2>::default();
+        array[0] = 1;
+        array[1] = 2;
+        let serialized = bincode::serialize(&array).unwrap();
+        let deserialized = bincode::deserialize::<GenericArray<u8, typenum::U2>>(&serialized);
+        assert!(deserialized.is_ok());
+        let array = deserialized.unwrap();
+        assert_eq!(array[0], 1);
+        assert_eq!(array[1], 2);
+    }
+
+    #[test]
+    fn test_serialized_size() {
+        let array = GenericArray::<u8, typenum::U1>::default();
+        let size = bincode::serialized_size(&array).unwrap();
+        assert_eq!(size, 1);
+    }
+
+}