add events for FungibleStakedSui creation and redemption

crates/sui-framework/packages/sui-system/sources/validator.move

@@ -160,6 +160,21 @@ module sui_system::validator {
         reward_amount: u64,
     }
 
+    /// Event emitted when a staked SUI is converted to a fungible staked SUI.
+    public struct ConvertingToFungibleStakedSuiEvent has copy, drop {
+        pool_id: ID,
+        stake_activation_epoch: u64,
+        staked_sui_principal_amount: u64,
+        fungible_staked_sui_amount: u64,
+    }
+
+    /// Event emitted when a fungible staked SUI is redeemed.
+    public struct RedeemingFungibleStakedSuiEvent has copy, drop {
+        pool_id: ID,
+        fungible_staked_sui_amount: u64,
+        sui_amount: u64,
+    }
+
     public(package) fun new_metadata(
         sui_address: address,
         protocol_pubkey_bytes: vector<u8>,
@@ -311,15 +326,41 @@ module sui_system::validator {
         staked_sui: StakedSui,
         ctx: &mut TxContext,
     ) : FungibleStakedSui {
-        self.staking_pool.convert_to_fungible_staked_sui(staked_sui, ctx)
+        let stake_activation_epoch = staked_sui.stake_activation_epoch();
+        let staked_sui_principal_amount = staked_sui.staked_sui_amount();
+
+        let fungible_staked_sui = self.staking_pool.convert_to_fungible_staked_sui(staked_sui, ctx);
+
+        event::emit(
+            ConvertingToFungibleStakedSuiEvent {
+                pool_id: self.staking_pool_id(),
+                stake_activation_epoch,
+                staked_sui_principal_amount,
+                fungible_staked_sui_amount: fungible_staked_sui.value(),
+            }
+        );
+
+        fungible_staked_sui
     }
 
     public(package) fun redeem_fungible_staked_sui(
         self: &mut Validator,
         fungible_staked_sui: FungibleStakedSui,
         ctx: &TxContext,
     ) : Balance<SUI> {
-        self.staking_pool.redeem_fungible_staked_sui(fungible_staked_sui, ctx)
+        let fungible_staked_sui_amount = fungible_staked_sui.value();
+
+        let sui = self.staking_pool.redeem_fungible_staked_sui(fungible_staked_sui, ctx);
+
+        event::emit(
+            RedeemingFungibleStakedSuiEvent {
+                pool_id: self.staking_pool_id(),
+                fungible_staked_sui_amount,
+                sui_amount: sui.value(),
+            }
+        );
+
+        sui
     }
 
     /// Request to add stake to the validator's staking pool at genesis