remove mining_pool from stake_state (#4804)

programs/stake_api/src/stake_state.rs

@@ -18,13 +18,6 @@ use std::cmp;
 pub enum StakeState {
     Uninitialized,
     Stake(Stake),
-    MiningPool {
-        /// epoch for which this Pool will redeem rewards
-        epoch: u64,
-
-        /// the number of lamports each point is worth
-        point_value: f64,
-    },
     RewardsPool,
 }
 
@@ -430,10 +423,8 @@ mod tests {
             Err(InstructionError::InsufficientFunds)
         );
 
-        let stake_state = StakeState::MiningPool {
+        let stake_state = StakeState::RewardsPool;
-            epoch: 0,
+
-            point_value: 0.0,
-        };
         stake_keyed_account.set_state(&stake_state).unwrap();
         assert!(stake_keyed_account
             .delegate_stake(&vote_keyed_account, 0, &current)
@@ -627,10 +618,7 @@ mod tests {
         let mut to_keyed_account = KeyedAccount::new(&to, false, &mut to_account);
 
         let mut stake_keyed_account = KeyedAccount::new(&stake_pubkey, true, &mut stake_account);
-        let stake_state = StakeState::MiningPool {
+        let stake_state = StakeState::RewardsPool;
-            epoch: 0,
-            point_value: 0.0,
-        };
         stake_keyed_account.set_state(&stake_state).unwrap();
 
         assert_eq!(

runtime/src/stakes.rs

@@ -128,14 +128,6 @@ impl Stakes {
         &self.vote_accounts
     }
 
-    pub fn mining_pools(&self) -> impl Iterator<Item = (&Pubkey, &Account)> {
-        self.stake_accounts
-            .iter()
-            .filter(|(_key, account)| match StakeState::from(account) {
-                Some(StakeState::MiningPool { .. }) => true,
-                _ => false,
-            })
-    }
     pub fn rewards_pools(&self) -> impl Iterator<Item = (&Pubkey, &Account)> {
         self.stake_accounts
             .iter()