Tidy up SSZ testing on types crate

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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);
+    }
+}

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 {
+    fn into_beacon_block(self) -> Option<BeaconBlock> {
-        self
+        Some(self)
     }
 }

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 {
+    fn into_beacon_state(self) -> Option<BeaconState> {
-        self
+        Some(self)
     }
 }

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {

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 crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
-    use rand::{prng::XorShiftRng, SeedableRng};
 
     #[test]
     pub fn test_ssz_round_trip() {