Move genesis code into its own crate

Cargo.toml

@@ -34,6 +34,7 @@ name = "lighthouse"
 members = [
 	"beacon_chain/attestation_validation",
 	"beacon_chain/chain",
+	"beacon_chain/genesis",
 	"beacon_chain/naive_fork_choice",
 	"beacon_chain/spec",
 	"beacon_chain/state-transition",

beacon_chain/chain/src/lib.rs

@@ -9,7 +9,6 @@ extern crate validator_induction;
 extern crate validator_shuffling;
 
 mod block_processing;
-mod genesis;
 mod maps;
 mod stores;
 mod transition;

beacon_chain/genesis/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "genesis"
+version = "0.1.0"
+authors = ["Paul Hauner <paul@paulhauner.com>"]
+
+[dependencies]
+bls = { path = "../utils/bls"  }
+spec = { path = "../spec"  }
+types = { path = "../types"  }
+validator_induction = { path = "../validator_induction"  }
+validator_shuffling = { path = "../validator_shuffling"  }

beacon_chain/genesis/src/beacon_state.rs

@@ -7,24 +7,16 @@ use validator_shuffling::{shard_and_committees_for_cycle, ValidatorAssignmentErr
 
 #[derive(Debug, PartialEq)]
 pub enum Error {
+    NoValidators,
     ValidationAssignmentError(ValidatorAssignmentError),
     NotImplemented,
 }
 
-impl From<ValidatorAssignmentError> for Error {
-    fn from(e: ValidatorAssignmentError) -> Error {
-        Error::ValidationAssignmentError(e)
-    }
-}
-
-/// Initialize a new ChainHead with genesis parameters.
-///
-/// Used when syncing a chain from scratch.
-pub fn genesis_states(
+pub fn genesis_beacon_state(
     spec: &ChainSpec,
-    initial_validators: Vec<ValidatorRegistration>,
+    initial_validators: &[ValidatorRegistration],
     genesis_time: u64,
-    processed_pow_receipt_root: Hash256,
+    processed_pow_receipt_root: &Hash256,
 ) -> Result<BeaconState, Error> {
     /*
      * Parse the ValidatorRegistrations into ValidatorRecords and induct them.
@@ -33,7 +25,7 @@ pub fn genesis_states(
      */
     let validators = {
         let mut inductor = ValidatorInductor::new(0, spec.shard_count, vec![]);
-        for registration in &initial_validators {
+        for registration in initial_validators {
             let _ = inductor.induct(&registration, ValidatorStatus::Active);
         }
         inductor.to_vec()
@@ -45,7 +37,7 @@ pub fn genesis_states(
      * Crystallizedstate stores two cycles, so we simply repeat the same assignment twice.
      */
     let _shard_and_committee_for_slots = {
-        let mut a = shard_and_committees_for_cycle(&vec![0; 32], &validators, 0, &spec)?;
+        let mut a = shard_and_committees_for_cycle(&[0; 32], &validators, 0, &spec)?;
         let mut b = a.clone();
         a.append(&mut b);
         a
@@ -79,15 +71,15 @@ pub fn genesis_states(
          */
         randao_mix: spec.zero_hash,
         next_seed: spec.zero_hash,
-        shard_committees_at_slot: vec![],
+        shard_committees_at_slots: vec![],
         persistent_committees: vec![],
-        persisten_committee_reassignments: vec![],
+        persistent_committee_reassignments: vec![],
         /*
          * Finality
          */
         previous_justified_slot: spec.initial_slot_number,
         justified_slot: spec.initial_slot_number,
-        justified_bitfield: 0,
+        justification_bitfield: 0,
         finalized_slot: spec.initial_slot_number,
         /*
          * Recent state
@@ -99,59 +91,28 @@ pub fn genesis_states(
         /*
          * PoW receipt root
          */
-        processed_pow_receipt_root,
+        processed_pow_receipt_root: *processed_pow_receipt_root,
         candidate_pow_receipt_roots: vec![],
     })
 }
 
+impl From<ValidatorAssignmentError> for Error {
+    fn from(e: ValidatorAssignmentError) -> Error {
+        Error::ValidationAssignmentError(e)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     extern crate bls;
     extern crate validator_induction;
 
-    // TODO: implement genesis for `BeaconState`
-    // https://github.com/sigp/lighthouse/issues/99
-    //
-    /*
     use self::bls::{create_proof_of_possession, Keypair};
     use super::*;
     use types::{Address, Hash256, ValidatorRegistration};
 
-    #[test]
-    fn test_genesis_no_validators() {
-        let config = ChainConfig::standard();
-        let (act, cry) = genesis_states(&config).unwrap();
-
-        assert_eq!(cry.validator_set_change_slot, 0);
-        assert_eq!(cry.validators.len(), 0);
-        assert_eq!(cry.crosslinks.len(), config.shard_count as usize);
-        for cl in cry.crosslinks {
-            assert_eq!(cl.recently_changed, false);
-            assert_eq!(cl.slot, 0);
-            assert_eq!(cl.hash, Hash256::zero());
-        }
-        assert_eq!(cry.last_state_recalculation_slot, 0);
-        assert_eq!(cry.last_finalized_slot, 0);
-        assert_eq!(cry.last_justified_slot, 0);
-        assert_eq!(cry.justified_streak, 0);
-        assert_eq!(
-            cry.shard_and_committee_for_slots.len(),
-            (config.cycle_length as usize) * 2
-        );
-        assert_eq!(cry.deposits_penalized_in_period.len(), 0);
-        assert_eq!(cry.validator_set_delta_hash_chain, Hash256::zero());
-        assert_eq!(cry.pre_fork_version, INITIAL_FORK_VERSION);
-        assert_eq!(cry.post_fork_version, INITIAL_FORK_VERSION);
-        assert_eq!(cry.fork_slot_number, 0);
-
-        assert_eq!(act.pending_attestations.len(), 0);
-        assert_eq!(act.pending_specials.len(), 0);
-        assert_eq!(
-            act.recent_block_hashes,
-            vec![Hash256::zero(); config.cycle_length as usize]
-        );
-        assert_eq!(act.randao_mix, Hash256::zero());
-    }
+    // TODO: enhance these tests.
+    // https://github.com/sigp/lighthouse/issues/117
 
     fn random_registration() -> ValidatorRegistration {
         let keypair = Keypair::random();
@@ -164,45 +125,48 @@ mod tests {
         }
     }
 
-    #[test]
-    fn test_genesis_valid_validators() {
-        let mut config = ChainConfig::standard();
-        let validator_count = 5;
-
-        for _ in 0..validator_count {
-            config.initial_validators.push(random_registration());
+    fn random_registrations(n: usize) -> Vec<ValidatorRegistration> {
+        let mut output = Vec::with_capacity(n);
+        for _ in 0..n {
+            output.push(random_registration())
         }
-
-        let (_, cry) = genesis_states(&config).unwrap();
-
-        assert_eq!(cry.validators.len(), validator_count);
+        output
     }
 
     #[test]
-    fn test_genesis_invalid_validators() {
-        let mut config = ChainConfig::standard();
-        let good_validator_count = 5;
+    fn test_genesis() {
+        let spec = ChainSpec::foundation();
+        let genesis_time = 42;
+        let initial_validators = random_registrations(4);
+        let processed_pow_receipt_root = Hash256::from("pow_root".as_bytes());
 
-        for _ in 0..good_validator_count {
-            config.initial_validators.push(random_registration());
+        let state = genesis_beacon_state(
+            &spec,
+            &initial_validators,
+            genesis_time,
+            &processed_pow_receipt_root,
+        ).unwrap();
+
+        assert_eq!(state.validator_registry.len(), 4);
     }
 
-        let mut bad_v = random_registration();
-        let bad_kp = Keypair::random();
-        bad_v.proof_of_possession = create_proof_of_possession(&bad_kp);
-        config.initial_validators.push(bad_v);
+    #[test]
+    fn test_genesis_bad_validator() {
+        let spec = ChainSpec::foundation();
+        let genesis_time = 42;
+        let mut initial_validators = random_registrations(5);
+        let processed_pow_receipt_root = Hash256::from("pow_root".as_bytes());
 
-        let mut bad_v = random_registration();
-        bad_v.withdrawal_shard = config.shard_count + 1;
-        config.initial_validators.push(bad_v);
+        let random_kp = Keypair::random();
+        initial_validators[4].proof_of_possession = create_proof_of_possession(&random_kp);
 
-        let (_, cry) = genesis_states(&config).unwrap();
+        let state = genesis_beacon_state(
+            &spec,
+            &initial_validators,
+            genesis_time,
+            &processed_pow_receipt_root,
+        ).unwrap();
 
-        assert!(
-            config.initial_validators.len() != good_validator_count,
-            "test is invalid"
-        );
-        assert_eq!(cry.validators.len(), good_validator_count);
+        assert_eq!(state.validator_registry.len(), 4);
     }
-    */
 }

beacon_chain/genesis/src/lib.rs

@@ -0,0 +1,7 @@
+extern crate spec;
+extern crate types;
+extern crate validator_induction;
+extern crate validator_shuffling;
+
+pub mod beacon_state;
+

beacon_chain/spec/src/lib.rs

@@ -4,6 +4,7 @@ mod foundation;
 
 use types::{Address, Hash256};
 
+#[derive(PartialEq, Debug)]
 pub struct ChainSpec {
     /*
      * Misc