Add SpecialRecord struct

beacon_chain/types/src/lib.rs

@@ -10,6 +10,7 @@ pub mod chain_config;
 pub mod block;
 pub mod crosslink_record;
 pub mod shard_and_committee;
+pub mod special_record;
 pub mod validator_record;
 
 use self::ethereum_types::{
@@ -27,6 +28,7 @@ pub use chain_config::ChainConfig;
 pub use block::Block;
 pub use crosslink_record::CrosslinkRecord;
 pub use shard_and_committee::ShardAndCommittee;
+pub use special_record::{ SpecialRecord, SpecialRecordKind };
 pub use validator_record::ValidatorRecord;
 
 pub type Hash256 = H256;

beacon_chain/types/src/special_record.rs

@@ -0,0 +1,89 @@
+use super::ssz::{ Encodable, SszStream };
+
+
+/// The value of the "type" field of SpecialRecord.
+///
+/// Note: this value must serialize to a u8 and therefore must not be greater than 255.
+#[derive(Debug, PartialEq, Clone, Copy)]
+pub enum SpecialRecordKind {
+    Logout = 0,
+    CasperSlashing = 1,
+    RandaoChange = 2,
+}
+
+
+/// The structure used in the `BeaconBlock.specials` field.
+#[derive(Debug, PartialEq, Clone)]
+pub struct SpecialRecord {
+    pub kind: SpecialRecordKind,
+    pub data: Vec<u8>,
+}
+
+impl SpecialRecord {
+    pub fn logout(data: &[u8]) -> Self {
+        Self {
+            kind: SpecialRecordKind::Logout,
+            data: data.to_vec(),
+        }
+    }
+
+    pub fn casper_slashing(data: &[u8]) -> Self {
+        Self {
+            kind: SpecialRecordKind::CasperSlashing,
+            data: data.to_vec(),
+        }
+    }
+
+    pub fn randao_change(data: &[u8]) -> Self {
+        Self {
+            kind: SpecialRecordKind::RandaoChange,
+            data: data.to_vec(),
+        }
+    }
+}
+
+impl Encodable for SpecialRecord {
+    fn ssz_append(&self, s: &mut SszStream) {
+        s.append(&self.kind);
+        s.append_vec(&self.data);
+    }
+}
+
+impl Encodable for SpecialRecordKind {
+    fn ssz_append(&self, s: &mut SszStream) {
+        s.append(&(*self as u8));
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    pub fn test_special_record_ssz() {
+        let s = SpecialRecord::logout(&vec![]);
+        let mut ssz_stream = SszStream::new();
+        ssz_stream.append(&s);
+        let ssz = ssz_stream.drain();
+        assert_eq!(ssz, vec![0, 0, 0, 0, 0]);
+
+        let s = SpecialRecord::casper_slashing(&vec![]);
+        let mut ssz_stream = SszStream::new();
+        ssz_stream.append(&s);
+        let ssz = ssz_stream.drain();
+        assert_eq!(ssz, vec![1, 0, 0, 0, 0]);
+
+        let s = SpecialRecord::randao_change(&vec![]);
+        let mut ssz_stream = SszStream::new();
+        ssz_stream.append(&s);
+        let ssz = ssz_stream.drain();
+        assert_eq!(ssz, vec![2, 0, 0, 0, 0]);
+
+        let s = SpecialRecord::randao_change(&vec![42, 43, 44]);
+        let mut ssz_stream = SszStream::new();
+        ssz_stream.append(&s);
+        let ssz = ssz_stream.drain();
+        assert_eq!(ssz, vec![2, 0, 0, 0, 3, 42, 43, 44]);
+    }
+}