Update v0.6: mandatory deposits (ethereum/consensus-specs#758)

beacon/src/error.rs

@@ -96,6 +96,8 @@ pub enum Error {
 	TooManyAttestations,
 	/// Too many deposits in a block.
 	TooManyDeposits,
+	/// Too few deposits in a block.
+	TooFewDeposits,
 	/// Too many voluntary exits in a block.
 	TooManyVoluntaryExits,
 	/// Too many transfers in a block.

beacon/src/eth1.rs

@@ -34,8 +34,7 @@ pub struct Eth1Data {
 	/// Root of the deposit tree
 	pub deposit_root: H256,
 	/// Total number of deposits
-	// TODO: this field is not present in current test spec.
-	// pub deposit_count: u64,
+	pub deposit_count: u64,
 	/// Block hash
 	pub block_hash: H256,
 }
@@ -45,8 +44,7 @@ impl Eth1Data {
 	pub fn empty() -> Self {
 		Self {
 			deposit_root: H256::default(),
-			// TODO: this field is not present in current test spec.
-			// deposit_count: 0,
+			deposit_count: 0,
 			block_hash: H256::default(),
 		}
 	}

beacon/src/lib.rs

@@ -61,6 +61,7 @@ pub use executive::*;
 pub use primitives::*;
 
 use ssz::Hashable;
+use core::cmp;
 
 /// Gwei as in the currency ETH.
 pub type Gwei = u64;
@@ -202,6 +203,10 @@ pub fn apply_transaction<C: Config>(block: &mut UnsealedBeaconBlock, state: &mut
 pub fn finalize_block<C: Config>(block: &mut UnsealedBeaconBlock, state: &mut BeaconState, config: &C) -> Result<(), Error> {
 	let mut executive = Executive::new(state, config);
 
+	if block.body.deposits.len() != cmp::min(config.max_deposits(), (executive.state().latest_eth1_data.deposit_count - executive.state().deposit_index) as usize) {
+		return Err(Error::TooFewDeposits)
+	}
+
 	executive.process_block_header(block)?;
 	Ok(())
 }
@@ -255,6 +260,9 @@ pub fn execute_block<C: Config>(block: &BeaconBlock, state: &mut BeaconState, co
 			if block.body.deposits.len() > config.max_deposits() {
 				return Err(Error::TooManyDeposits)
 			}
+			if block.body.deposits.len() != cmp::min(config.max_deposits(), (executive.state().latest_eth1_data.deposit_count - executive.state().deposit_index) as usize) {
+				return Err(Error::TooFewDeposits)
+			}
 			for deposit in &block.body.deposits {
 				executive.push_deposit(deposit.clone())?;
 			}