refactor: centralize the zero-amount check for burning

refactor: Balances -> TokenBalances

bins/revm-test/src/bin/burntpix/main.rs

@@ -4,7 +4,7 @@ use regex::bytes::Regex;
 use revm::{
     db::{CacheDB, EmptyDB},
     primitives::{
-        address, hex, keccak256, AccountInfo, Address, Balances, Bytecode, Bytes, ExecutionResult,
+        address, hex, keccak256, AccountInfo, Address, TokenBalances, Bytecode, Bytes, ExecutionResult,
         Output, TransactTo, B256, BASE_TOKEN_ID, U256,
     },
     Evm,
@@ -102,7 +102,7 @@ fn try_from_hex_to_u32(hex: &str) -> eyre::Result<u32> {
 fn insert_account_info(cache_db: &mut CacheDB<EmptyDB>, addr: Address, code: Bytes) {
     let code_hash = hex::encode(keccak256(code.clone()));
     let account_info = AccountInfo::new(
-        Balances::from([(BASE_TOKEN_ID, U256::ZERO)]),
+        TokenBalances::from([(BASE_TOKEN_ID, U256::ZERO)]),
         0,
         B256::from_str(&code_hash).unwrap(),
         Bytecode::new_raw(code),

crates/primitives/src/state.rs

@@ -21,7 +21,7 @@ pub type EvmStorage = HashMap<U256, EvmStorageSlot>;
 #[derive(Debug, Clone, PartialEq, Eq, Default)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Account {
-    /// Balances, nonce, and code.
+    /// TokenBalances, nonce, and code.
     pub info: AccountInfo,
     /// Storage cache
     pub storage: EvmStorage,
@@ -184,17 +184,14 @@ impl EvmStorageSlot {
     }
 }
 
-// TODO: create a custom type with a suggestive name for the (U256, U256) tuple. This will make
-/// the code more readable - especially in places where the tuple members are currently accessed
-/// via `.0` and `.1`.
-pub type Balances = HashMap<U256, U256>;
+pub type TokenBalances = HashMap<U256, U256>;
 
 /// The account information.
 #[derive(Clone, Debug, Eq)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct AccountInfo {
     /// Token balances.
-    pub balances: Balances,
+    pub balances: TokenBalances,
     /// Account nonce.
     pub nonce: u64,
     /// code hash,
@@ -248,7 +245,7 @@ impl Hash for AccountInfo {
 }
 
 impl AccountInfo {
-    pub fn new(balances: Balances, nonce: u64, code_hash: B256, code: Bytecode) -> Self {
+    pub fn new(balances: TokenBalances, nonce: u64, code_hash: B256, code: Bytecode) -> Self {
         Self {
             balances,
             nonce,
@@ -379,8 +376,8 @@ impl AccountInfo {
     }
 }
 
-impl From<Balances> for AccountInfo {
-    fn from(balances: Balances) -> Self {
+impl From<TokenBalances> for AccountInfo {
+    fn from(balances: TokenBalances) -> Self {
         AccountInfo {
             balances,
             ..Default::default()

crates/primitives/src/utilities.rs

@@ -1,5 +1,5 @@
 use crate::{
-    b256, Balances, B256, BASE_TOKEN_ID, BLOB_GASPRICE_UPDATE_FRACTION, MIN_BLOB_GASPRICE,
+    b256, TokenBalances, B256, BASE_TOKEN_ID, BLOB_GASPRICE_UPDATE_FRACTION, MIN_BLOB_GASPRICE,
     TARGET_BLOB_GAS_PER_BLOCK,
 };
 pub use alloy_primitives::keccak256;
@@ -32,8 +32,8 @@ pub fn calc_blob_gasprice(excess_blob_gas: u64) -> u128 {
 }
 
 /// Creates a simple balances map with the given balance for the base token.
-pub fn init_balances(base_balance: U256) -> Balances {
-    let mut balances = Balances::new();
+pub fn init_balances(base_balance: U256) -> TokenBalances {
+    let mut balances = TokenBalances::new();
     balances.insert(BASE_TOKEN_ID, base_balance);
     balances
 }

crates/revm/src/context.rs

@@ -201,10 +201,6 @@ impl<EXT, DB: Database> Host for Context<EXT, DB> {
     }
 
     fn burn(&mut self, burner: Address, sub_id: U256, token_holder: Address, amount: U256) -> bool {
-        if amount == U256::ZERO {
-            return false;
-        }
-
         self.evm.inner.journaled_state.burn(
             burner,
             sub_id,
@@ -214,7 +210,7 @@ impl<EXT, DB: Database> Host for Context<EXT, DB> {
         )
     }
     fn mint(&mut self, minter: Address, recipient: Address, sub_id: U256, amount: U256) -> bool {
-        // TODO: also return the generated Token Id from this function
+        // TODO: also return the generated Token Id from this function?
 
         if amount == U256::ZERO {
             return false;

crates/revm/src/context/evm_context.rs

@@ -296,7 +296,7 @@ pub(crate) mod test_utils {
     use crate::{
         db::{CacheDB, EmptyDB},
         journaled_state::JournaledState,
-        primitives::{address, Address, Balances, SpecId, B256},
+        primitives::{address, Address, SpecId, TokenBalances, B256},
     };
 
     /// Mock caller address.
@@ -324,7 +324,7 @@ pub(crate) mod test_utils {
     pub fn create_cache_db_evm_context_with_balances(
         env: Box<Env>,
         mut db: CacheDB<EmptyDB>,
-        balances: Balances,
+        balances: TokenBalances,
     ) -> EvmContext<CacheDB<EmptyDB>> {
         db.insert_account_info(
             test_utils::MOCK_CALLER,

crates/revm/src/db/alloydb.rs

@@ -89,7 +89,7 @@ impl<T: Transport + Clone, N: Network, P: Provider<T, N>> DatabaseRef for AlloyD
         let nonce = nonce?;
 
         Ok(Some(AccountInfo::new(
-            Balances::from([(BASE_TOKEN_ID, balance)]),
+            TokenBalances::from([(BASE_TOKEN_ID, balance)]),
             nonce,
             code_hash,
             code,

crates/revm/src/journaled_state.rs

@@ -828,6 +828,10 @@ impl JournaledState {
         amount: U256,
         db: &mut DB,
     ) -> bool {
+        if amount == U256::ZERO {
+            return false;
+        }
+
         if self.load_native_token_ids(db).is_err() {
             return false;
         }
@@ -838,7 +842,6 @@ impl JournaledState {
 
         let token_id = token_id_address(burner, sub_id);
 
-        // TODO: shouldn't this be verified before this function is called?
         let result = db.is_token_id_valid(token_id);
         if result.is_err() || result.is_ok_and(|r| !r) {
             return false;

crates/revm/src/sablier/test_native_tokens.rs

@@ -2,8 +2,8 @@
 mod test {
     use crate::{
         primitives::{
-            address, bytes, keccak256, token_id_address, AccountInfo, Address, Balances, Bytecode,
-            Bytes, SpecId, TokenTransfer, TransactTo, B256, BASE_TOKEN_ID, U256,
+            address, bytes, keccak256, token_id_address, AccountInfo, Address, Bytecode, Bytes,
+            SpecId, TokenBalances, TokenTransfer, TransactTo, B256, BASE_TOKEN_ID, U256,
         },
         sablier::native_tokens::{ADDRESS as NATIVE_TOKENS_PRECOMPILE_ADDRESS, BALANCEOF_SELECTOR},
         Evm, InMemoryDB,
@@ -705,7 +705,7 @@ mod test {
                 db.insert_account_info(caller_eoa, caller_info);
 
                 let token_transferrer_mock_bytecode = &NAIVE_TOKEN_TRANSFERRER_MOCK_BYTECODE;
-                let mut balances: Balances = HashMap::new();
+                let mut balances: TokenBalances = HashMap::new();
                 for (token_id, balance) in token_ids
                     .iter()
                     .zip(token_transferrer_balances.iter())