From d84850b892ba2bc5ffaafb4d9b6f267e64ad88c5 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Fri, 15 Mar 2019 15:40:28 +1100
Subject: [PATCH] Add `BeaconBlockHeader` type.

---
 eth2/types/src/beacon_block_header.rs | 38 +++++++++++++++++++++++++++
 eth2/types/src/lib.rs                 |  2 ++
 2 files changed, 40 insertions(+)
 create mode 100644 eth2/types/src/beacon_block_header.rs

diff --git a/eth2/types/src/beacon_block_header.rs b/eth2/types/src/beacon_block_header.rs
new file mode 100644
index 000000000..029c7e56b
--- /dev/null
+++ b/eth2/types/src/beacon_block_header.rs
@@ -0,0 +1,38 @@
+use crate::test_utils::TestRandom;
+use crate::*;
+use bls::Signature;
+use rand::RngCore;
+use serde_derive::{Deserialize, Serialize};
+use ssz::TreeHash;
+use ssz_derive::{Decode, Encode, SignedRoot, TreeHash};
+use test_random_derive::TestRandom;
+
+/// A header of a `BeaconBlock`.
+///
+/// Spec v0.5.0
+#[derive(
+    Debug,
+    PartialEq,
+    Clone,
+    Serialize,
+    Deserialize,
+    Encode,
+    Decode,
+    TreeHash,
+    TestRandom,
+    SignedRoot,
+)]
+pub struct BeaconBlockHeader {
+    pub slot: Slot,
+    pub previous_block_root: Hash256,
+    pub state_root: Hash256,
+    pub block_body_root: Hash256,
+    pub signature: Signature,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    ssz_tests!(BeaconBlockHeader);
+}
diff --git a/eth2/types/src/lib.rs b/eth2/types/src/lib.rs
index 7b1d84837..2fcb3237d 100644
--- a/eth2/types/src/lib.rs
+++ b/eth2/types/src/lib.rs
@@ -9,6 +9,7 @@ pub mod attestation_data_and_custody_bit;
 pub mod attester_slashing;
 pub mod beacon_block;
 pub mod beacon_block_body;
+pub mod beacon_block_header;
 pub mod beacon_state;
 pub mod chain_spec;
 pub mod crosslink;
@@ -43,6 +44,7 @@ pub use crate::attestation_data_and_custody_bit::AttestationDataAndCustodyBit;
 pub use crate::attester_slashing::AttesterSlashing;
 pub use crate::beacon_block::BeaconBlock;
 pub use crate::beacon_block_body::BeaconBlockBody;
+pub use crate::beacon_block_header::BeaconBlockHeader;
 pub use crate::beacon_state::{BeaconState, Error as BeaconStateError, RelativeEpoch};
 pub use crate::chain_spec::{ChainSpec, Domain};
 pub use crate::crosslink::Crosslink;