From ad91648f30248e0e62146de14112e9fd50987cd4 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Fri, 4 Jan 2019 18:10:14 +1100
Subject: [PATCH] Tidy up SSZ testing on types crate

---
 beacon_chain/types/src/attestation.rs          |  3 +--
 beacon_chain/types/src/attestation_data.rs     |  3 +--
 beacon_chain/types/src/beacon_block.rs         |  3 +--
 beacon_chain/types/src/beacon_block_body.rs    |  3 +--
 beacon_chain/types/src/beacon_state.rs         | 18 ++++++++++++++++++
 .../src/candidate_pow_receipt_root_record.rs   |  3 +--
 beacon_chain/types/src/casper_slashing.rs      |  3 +--
 beacon_chain/types/src/crosslink_record.rs     |  3 +--
 beacon_chain/types/src/deposit_data.rs         |  3 +--
 beacon_chain/types/src/deposit_input.rs        |  3 +--
 beacon_chain/types/src/exit.rs                 |  3 +--
 beacon_chain/types/src/fork_data.rs            |  3 +--
 .../types/src/pending_attestation_record.rs    |  3 +--
 beacon_chain/types/src/proposal_signed_data.rs |  3 +--
 beacon_chain/types/src/proposer_slashing.rs    |  3 +--
 beacon_chain/types/src/readers/block_reader.rs |  6 +++---
 beacon_chain/types/src/readers/state_reader.rs |  6 +++---
 beacon_chain/types/src/shard_committee.rs      |  3 +--
 .../types/src/shard_reassignment_record.rs     |  3 +--
 beacon_chain/types/src/slashable_vote_data.rs  |  3 +--
 beacon_chain/types/src/validator_record.rs     |  3 +--
 21 files changed, 42 insertions(+), 42 deletions(-)

diff --git a/beacon_chain/types/src/attestation.rs b/beacon_chain/types/src/attestation.rs
index 7a94eee51c..fb8b946a5c 100644
--- a/beacon_chain/types/src/attestation.rs
+++ b/beacon_chain/types/src/attestation.rs
@@ -64,8 +64,7 @@ impl<T: RngCore> TestRandom<T> for Attestation {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/attestation_data.rs b/beacon_chain/types/src/attestation_data.rs
index 616c52d790..e1d70e2b01 100644
--- a/beacon_chain/types/src/attestation_data.rs
+++ b/beacon_chain/types/src/attestation_data.rs
@@ -104,8 +104,7 @@ impl<T: RngCore> TestRandom<T> for AttestationData {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/beacon_block.rs b/beacon_chain/types/src/beacon_block.rs
index 826667d5ef..30a1bd83b0 100644
--- a/beacon_chain/types/src/beacon_block.rs
+++ b/beacon_chain/types/src/beacon_block.rs
@@ -79,8 +79,7 @@ impl<T: RngCore> TestRandom<T> for BeaconBlock {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/beacon_block_body.rs b/beacon_chain/types/src/beacon_block_body.rs
index f5ac223432..8bcf1af334 100644
--- a/beacon_chain/types/src/beacon_block_body.rs
+++ b/beacon_chain/types/src/beacon_block_body.rs
@@ -59,8 +59,7 @@ impl<T: RngCore> TestRandom<T> for BeaconBlockBody {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/beacon_state.rs b/beacon_chain/types/src/beacon_state.rs
index f2d8f6aeb5..7bd0283c59 100644
--- a/beacon_chain/types/src/beacon_state.rs
+++ b/beacon_chain/types/src/beacon_state.rs
@@ -166,3 +166,21 @@ impl<T: RngCore> TestRandom<T> for BeaconState {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::super::ssz::ssz_encode;
+    use super::*;
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
+
+    #[test]
+    pub fn test_ssz_round_trip() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = BeaconState::random_for_test(&mut rng);
+
+        let bytes = ssz_encode(&original);
+        let (decoded, _) = <_>::ssz_decode(&bytes, 0).unwrap();
+
+        assert_eq!(original, decoded);
+    }
+}
diff --git a/beacon_chain/types/src/candidate_pow_receipt_root_record.rs b/beacon_chain/types/src/candidate_pow_receipt_root_record.rs
index 663c3e1dbf..5f260c4234 100644
--- a/beacon_chain/types/src/candidate_pow_receipt_root_record.rs
+++ b/beacon_chain/types/src/candidate_pow_receipt_root_record.rs
@@ -44,8 +44,7 @@ impl<T: RngCore> TestRandom<T> for CandidatePoWReceiptRootRecord {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/casper_slashing.rs b/beacon_chain/types/src/casper_slashing.rs
index f3c1b5d180..08dbd9ff33 100644
--- a/beacon_chain/types/src/casper_slashing.rs
+++ b/beacon_chain/types/src/casper_slashing.rs
@@ -44,8 +44,7 @@ impl<T: RngCore> TestRandom<T> for CasperSlashing {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/crosslink_record.rs b/beacon_chain/types/src/crosslink_record.rs
index 9e525664a0..ae6c5bf929 100644
--- a/beacon_chain/types/src/crosslink_record.rs
+++ b/beacon_chain/types/src/crosslink_record.rs
@@ -54,8 +54,7 @@ impl<T: RngCore> TestRandom<T> for CrosslinkRecord {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/deposit_data.rs b/beacon_chain/types/src/deposit_data.rs
index b236709d20..5dcd20c7cb 100644
--- a/beacon_chain/types/src/deposit_data.rs
+++ b/beacon_chain/types/src/deposit_data.rs
@@ -49,8 +49,7 @@ impl<T: RngCore> TestRandom<T> for DepositData {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/deposit_input.rs b/beacon_chain/types/src/deposit_input.rs
index 3a9a08412c..d7e2272e91 100644
--- a/beacon_chain/types/src/deposit_input.rs
+++ b/beacon_chain/types/src/deposit_input.rs
@@ -55,8 +55,7 @@ impl<T: RngCore> TestRandom<T> for DepositInput {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/exit.rs b/beacon_chain/types/src/exit.rs
index 6a6d573051..eeac11ce75 100644
--- a/beacon_chain/types/src/exit.rs
+++ b/beacon_chain/types/src/exit.rs
@@ -49,8 +49,7 @@ impl<T: RngCore> TestRandom<T> for Exit {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/fork_data.rs b/beacon_chain/types/src/fork_data.rs
index e779c797e7..7cd4dc3ac5 100644
--- a/beacon_chain/types/src/fork_data.rs
+++ b/beacon_chain/types/src/fork_data.rs
@@ -48,8 +48,7 @@ impl<T: RngCore> TestRandom<T> for ForkData {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/pending_attestation_record.rs b/beacon_chain/types/src/pending_attestation_record.rs
index aa289e9048..3bebf5676d 100644
--- a/beacon_chain/types/src/pending_attestation_record.rs
+++ b/beacon_chain/types/src/pending_attestation_record.rs
@@ -54,8 +54,7 @@ impl<T: RngCore> TestRandom<T> for PendingAttestationRecord {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/proposal_signed_data.rs b/beacon_chain/types/src/proposal_signed_data.rs
index 7a01fc10a5..e38a9cadb2 100644
--- a/beacon_chain/types/src/proposal_signed_data.rs
+++ b/beacon_chain/types/src/proposal_signed_data.rs
@@ -49,8 +49,7 @@ impl<T: RngCore> TestRandom<T> for ProposalSignedData {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/proposer_slashing.rs b/beacon_chain/types/src/proposer_slashing.rs
index 0ae1c6e663..3754c3b328 100644
--- a/beacon_chain/types/src/proposer_slashing.rs
+++ b/beacon_chain/types/src/proposer_slashing.rs
@@ -60,8 +60,7 @@ impl<T: RngCore> TestRandom<T> for ProposerSlashing {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/readers/block_reader.rs b/beacon_chain/types/src/readers/block_reader.rs
index e1cba224d2..1698a0380a 100644
--- a/beacon_chain/types/src/readers/block_reader.rs
+++ b/beacon_chain/types/src/readers/block_reader.rs
@@ -5,7 +5,7 @@ pub trait BeaconBlockReader {
     fn parent_root(&self) -> Hash256;
     fn state_root(&self) -> Hash256;
     fn canonical_root(&self) -> Hash256;
-    fn to_beacon_block(self) -> BeaconBlock;
+    fn into_beacon_block(self) -> Option<BeaconBlock>;
 }
 
 impl BeaconBlockReader for BeaconBlock {
@@ -25,7 +25,7 @@ impl BeaconBlockReader for BeaconBlock {
         self.canonical_root()
     }
 
-    fn to_beacon_block(self) -> BeaconBlock {
-        self
+    fn into_beacon_block(self) -> Option<BeaconBlock> {
+        Some(self)
     }
 }
diff --git a/beacon_chain/types/src/readers/state_reader.rs b/beacon_chain/types/src/readers/state_reader.rs
index a43ef9930e..cbbf0854cb 100644
--- a/beacon_chain/types/src/readers/state_reader.rs
+++ b/beacon_chain/types/src/readers/state_reader.rs
@@ -3,7 +3,7 @@ use crate::{BeaconState, Hash256};
 pub trait BeaconStateReader {
     fn slot(&self) -> u64;
     fn canonical_root(&self) -> Hash256;
-    fn to_beacon_state(self) -> BeaconState;
+    fn into_beacon_state(self) -> Option<BeaconState>;
 }
 
 impl BeaconStateReader for BeaconState {
@@ -15,7 +15,7 @@ impl BeaconStateReader for BeaconState {
         self.canonical_root()
     }
 
-    fn to_beacon_state(self) -> BeaconState {
-        self
+    fn into_beacon_state(self) -> Option<BeaconState> {
+        Some(self)
     }
 }
diff --git a/beacon_chain/types/src/shard_committee.rs b/beacon_chain/types/src/shard_committee.rs
index 073dd01769..d920f7db3a 100644
--- a/beacon_chain/types/src/shard_committee.rs
+++ b/beacon_chain/types/src/shard_committee.rs
@@ -37,8 +37,7 @@ impl<T: RngCore> TestRandom<T> for ShardCommittee {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/shard_reassignment_record.rs b/beacon_chain/types/src/shard_reassignment_record.rs
index e990afeac8..9bc014689a 100644
--- a/beacon_chain/types/src/shard_reassignment_record.rs
+++ b/beacon_chain/types/src/shard_reassignment_record.rs
@@ -48,8 +48,7 @@ impl<T: RngCore> TestRandom<T> for ShardReassignmentRecord {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/slashable_vote_data.rs b/beacon_chain/types/src/slashable_vote_data.rs
index 4d8e2eab30..5703853b2f 100644
--- a/beacon_chain/types/src/slashable_vote_data.rs
+++ b/beacon_chain/types/src/slashable_vote_data.rs
@@ -55,8 +55,7 @@ impl<T: RngCore> TestRandom<T> for SlashableVoteData {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {
diff --git a/beacon_chain/types/src/validator_record.rs b/beacon_chain/types/src/validator_record.rs
index 45b6c301af..374d956239 100644
--- a/beacon_chain/types/src/validator_record.rs
+++ b/beacon_chain/types/src/validator_record.rs
@@ -150,8 +150,7 @@ impl<T: RngCore> TestRandom<T> for ValidatorRecord {
 mod tests {
     use super::super::ssz::ssz_encode;
     use super::*;
-    use crate::test_utils::TestRandom;
-    use rand::{prng::XorShiftRng, SeedableRng};
+    use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
 
     #[test]
     pub fn test_ssz_round_trip() {