Functions to update token balance and supply

.changelog/unreleased/improvements/3029-token-balance-update-fns.md

@@ -0,0 +1,2 @@
+- Refactor and modularize the token balance and supply API.
+  ([\#3029](https://github.com/anoma/namada/pull/3029))

crates/apps/src/lib/node/ledger/shell/finalize_block.rs

@@ -766,7 +766,10 @@ mod test_finalize_block {
     use namada::proof_of_stake::{unjail_validator, ADDRESS as pos_address};
     use namada::replay_protection;
     use namada::tendermint::abci::types::{Misbehavior, MisbehaviorKind};
-    use namada::token::{Amount, DenominatedAmount, NATIVE_MAX_DECIMAL_PLACES};
+    use namada::token::{
+        read_balance, update_balance, Amount, DenominatedAmount,
+        NATIVE_MAX_DECIMAL_PLACES,
+    };
     use namada::tx::data::Fee;
     use namada::tx::{Authorization, Code, Data};
     use namada::vote_ext::ethereum_events;
@@ -842,14 +845,14 @@ mod test_finalize_block {
         let mut processed_txs = vec![];
 
         // Add unshielded balance for fee payment
-        let balance_key = token::storage_key::balance_key(
-            &shell.state.in_mem().native_token,
+        let native_token = shell.state.in_mem().native_token.clone();
+        update_balance(
+            &mut shell.state,
+            &native_token,
             &Address::from(&keypair.ref_to()),
-        );
-        shell
-            .state
-            .write(&balance_key, Amount::native_whole(1000))
-            .unwrap();
+            |_| Ok(Amount::native_whole(1000)),
+        )
+        .unwrap();
 
         // create some wrapper txs
         for i in 0u64..4 {
@@ -1143,14 +1146,14 @@ mod test_finalize_block {
             // add bertha's gas fees the pool
             {
                 let amt: Amount = 999_999_u64.into();
-                let pool_balance_key = token::storage_key::balance_key(
-                    &shell.state.in_mem().native_token,
+                let native_token = shell.state.in_mem().native_token.clone();
+                update_balance(
+                    &mut shell.state,
+                    &native_token,
                     &bridge_pool::BRIDGE_POOL_ADDRESS,
-                );
-                shell
-                    .state
-                    .write(&pool_balance_key, amt)
-                    .expect("Test failed");
+                    |_| Ok(amt),
+                )
+                .expect("Test failed");
             }
             // write transfer to storage
             let transfer = {
@@ -3117,12 +3120,12 @@ mod test_finalize_block {
             initial_balance,
         )
         .unwrap();
-        let balance_key = token::storage_key::balance_key(
+        let balance = read_balance(
+            &shell.state,
             &native_token,
             &Address::from(&keypair.to_public()),
-        );
-        let balance: Amount =
-            shell.state.read(&balance_key).unwrap().unwrap_or_default();
+        )
+        .unwrap();
         assert_eq!(balance, initial_balance);
 
         let mut wrapper =
@@ -3178,8 +3181,12 @@ mod test_finalize_block {
         assert_eq!(event.event_type.to_string(), String::from("applied"));
         let code = event.attributes.get("code").expect("Test failed").as_str();
         assert_eq!(code, String::from(ResultCode::InvalidTx).as_str());
-        let balance: Amount =
-            shell.state.read(&balance_key).unwrap().unwrap_or_default();
+        let balance = read_balance(
+            &shell.state,
+            &native_token,
+            &Address::from(&keypair.to_public()),
+        )
+        .unwrap();
 
         assert_eq!(balance, 0.into())
     }
@@ -3701,15 +3708,12 @@ mod test_finalize_block {
 
         // Slash pool balance
         let nam_address = shell.state.in_mem().native_token.clone();
-        let slash_balance_key = token::storage_key::balance_key(
+        let slash_pool_balance_init = read_balance(
+            &shell.state,
             &nam_address,
             &namada_proof_of_stake::SLASH_POOL_ADDRESS,
-        );
-        let slash_pool_balance_init: token::Amount = shell
-            .state
-            .read(&slash_balance_key)
-            .expect("must be able to read")
-            .unwrap_or_default();
+        )
+        .unwrap();
         debug_assert_eq!(slash_pool_balance_init, token::Amount::zero());
 
         let consensus_set: Vec<WeightedValidator> =
@@ -4858,14 +4862,8 @@ mod test_finalize_block {
         // NOTE: assumed that the only change in pos address balance by
         // advancing to the next epoch is minted inflation - no change occurs
         // due to slashing
-        let pos_balance_pre = shell
-            .state
-            .read::<token::Amount>(&token::storage_key::balance_key(
-                &staking_token,
-                &pos_address,
-            ))
-            .unwrap()
-            .unwrap_or_default();
+        let pos_balance_pre =
+            read_balance(&shell.state, &staking_token, &pos_address).unwrap();
         loop {
             next_block_for_inflation(
                 shell,
@@ -4877,14 +4875,8 @@ mod test_finalize_block {
                 break;
             }
         }
-        let pos_balance_post = shell
-            .state
-            .read::<token::Amount>(&token::storage_key::balance_key(
-                &staking_token,
-                &pos_address,
-            ))
-            .unwrap()
-            .unwrap_or_default();
+        let pos_balance_post =
+            read_balance(&shell.state, &staking_token, &pos_address).unwrap();
 
         (
             shell.state.in_mem().block.epoch,

crates/apps/src/lib/node/ledger/shell/init_chain.rs

@@ -511,7 +511,6 @@ where
                 continue;
             };
 
-            let mut total_token_balance = token::Amount::zero();
             for (owner, balance) in balances {
                 if let genesis::GenesisAddress::PublicKey(pk) = owner {
                     namada::account::init_account_storage(
@@ -535,15 +534,7 @@ where
                     balance.amount(),
                 )
                 .expect("Couldn't credit initial balance");
-                total_token_balance += balance.amount();
             }
-            // Write the total amount of tokens for the ratio
-            self.state
-                .write(
-                    &token::storage_key::minted_balance_key(token_address),
-                    total_token_balance,
-                )
-                .unwrap();
         }
         self.proceed_with(())
     }