Refactor and timestamp test

substrate/wasm-runtime/polkadot/src/runtime/staking.rs

@@ -3,6 +3,11 @@ use storage::Storage;
 use primitives::{BlockNumber, Balance, AccountID};
 use runtime::{system, session};
 
+// Each validator's stake has one amount in each of three states:
+// - inactive: free to be transferred
+// - active: currently representing a validator
+// - deactivating: recently representing a validator and not yet ready for transfer
+
 /// The length of a staking era in blocks.
 pub fn era_length() -> BlockNumber {
 	sessions_per_era() * session::length()
@@ -13,21 +18,26 @@ pub fn sessions_per_era() -> BlockNumber {
 	Storage::into(b"sta\0spe")
 }
 
+/// The length of a staking era in sessions.
+pub fn lockup_eras() -> BlockNumber {
+	Storage::into(b"sta\0lpe")
+}
+
 /// The era has changed - enact new staking set.
 ///
 /// NOTE: This always happens on a session change.
-pub fn next_era() {
+fn next_era() {
 	// TODO: evaluate desired staking amounts and nominations and optimise to find the best
 	// combination of validators, then use session::set_validators().
 }
 
 /// The balance of a given account.
-pub fn balance(who: &AccountID) -> Balance {
+pub fn balance_inactive(who: &AccountID) -> Balance {
 	Storage::into(&who.to_keyed_vec(b"sta\0bal\0"))
 }
 
 /// Transfer some unlocked staking balance to another staker.
-pub fn transfer_stake(transactor: &AccountID, dest: &AccountID, value: Balance) {
+pub fn transfer_inactive(transactor: &AccountID, dest: &AccountID, value: Balance) {
 	let from_key = transactor.to_keyed_vec(b"sta\0bal\0");
 	let from_balance: Balance = Storage::into(&from_key);
 	assert!(from_balance >= value);
@@ -42,14 +52,14 @@ pub fn transfer_stake(transactor: &AccountID, dest: &AccountID, value: Balance)
 ///
 /// Effects will be felt at the beginning of the next era.
 pub fn stake(_transactor: &AccountID) {
-	unimplemented!()
+	// TODO: record the desire for `_transactor` to activate their stake.
 }
 
 /// Retract the desire to stake for the transactor.
 ///
 /// Effects will be felt at the beginning of the next era.
 pub fn unstake(_transactor: &AccountID) {
-	unimplemented!()
+	// TODO: record the desire for `_transactor` to deactivate their stake.
 }
 
 /// Hook to be called prior to transaction processing.
@@ -88,8 +98,8 @@ mod tests {
 		], };
 
 		with_externalities(&mut t, || {
-			assert_eq!(staking::balance(&one), 42);
-			assert_eq!(staking::balance(&two), 0);
+			assert_eq!(staking::balance_inactive(&one), 42);
+			assert_eq!(staking::balance_inactive(&two), 0);
 		});
 	}
 
@@ -103,9 +113,9 @@ mod tests {
 		], };
 
 		with_externalities(&mut t, || {
-			staking::transfer_stake(&one, &two, 69);
-			assert_eq!(staking::balance(&one), 42);
-			assert_eq!(staking::balance(&two), 69);
+			staking::transfer_inactive(&one, &two, 69);
+			assert_eq!(staking::balance_inactive(&one), 42);
+			assert_eq!(staking::balance_inactive(&two), 69);
 		});
 	}
 }