Fix: Redundant account destruction after state modification

src/ethereum/cancun/fork.py

@@ -45,7 +45,6 @@
 from .state import (
     State,
     TransientStorage,
-    account_exists_and_is_empty,
     destroy_account,
     get_account,
     increment_nonce,
@@ -784,14 +783,11 @@ def process_transaction(
     coinbase_balance_after_mining_fee = get_account(
         block_env.state, block_env.coinbase
     ).balance + U256(transaction_fee)
-    if coinbase_balance_after_mining_fee != 0:
-        set_account_balance(
-            block_env.state,
-            block_env.coinbase,
-            coinbase_balance_after_mining_fee,
-        )
-    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
-        destroy_account(block_env.state, block_env.coinbase)
+    set_account_balance(
+        block_env.state,
+        block_env.coinbase,
+        coinbase_balance_after_mining_fee,
+    )
 
     for address in tx_output.accounts_to_delete:
         destroy_account(block_env.state, address)
@@ -836,9 +832,6 @@ def increase_recipient_balance(recipient: Account) -> None:
 
         modify_state(block_env.state, wd.address, increase_recipient_balance)
 
-        if account_exists_and_is_empty(block_env.state, wd.address):
-            destroy_account(block_env.state, wd.address)
-
 
 def check_gas_limit(gas_limit: Uint, parent_gas_limit: Uint) -> bool:
     """

src/ethereum/cancun/state.py

@@ -425,33 +425,6 @@ def account_has_storage(state: State, address: Address) -> bool:
     return address in state._storage_tries
 
 
-def account_exists_and_is_empty(state: State, address: Address) -> bool:
-    """
-    Checks if an account exists and has zero nonce, empty code and zero
-    balance.
-
-    Parameters
-    ----------
-    state:
-        The state
-    address:
-        Address of the account that needs to be checked.
-
-    Returns
-    -------
-    exists_and_is_empty : `bool`
-        True if an account exists and has zero nonce, empty code and zero
-        balance, False otherwise.
-    """
-    account = get_account_optional(state, address)
-    return (
-        account is not None
-        and account.nonce == Uint(0)
-        and account.code == b""
-        and account.balance == 0
-    )
-
-
 def is_account_alive(state: State, address: Address) -> bool:
     """
     Check whether is an account is both in the state and non empty.
@@ -476,10 +449,20 @@ def modify_state(
     state: State, address: Address, f: Callable[[Account], None]
 ) -> None:
     """
-    Modify an `Account` in the `State`.
+    Modify an `Account` in the `State`. If, after modification, the account
+    exists and has zero nonce, empty code, and zero balance, it is destroyed.
     """
     set_account(state, address, modify(get_account(state, address), f))
-    if account_exists_and_is_empty(state, address):
+
+    account = get_account_optional(state, address)
+    account_exists_and_is_empty = (
+        account is not None
+        and account.nonce == Uint(0)
+        and account.code == b""
+        and account.balance == 0
+    )
+
+    if account_exists_and_is_empty:
         destroy_account(state, address)
 
 

src/ethereum/osaka/fork.py

@@ -54,7 +54,6 @@
 from .state import (
     State,
     TransientStorage,
-    account_exists_and_is_empty,
     destroy_account,
     get_account,
     increment_nonce,
@@ -960,14 +959,11 @@ def process_transaction(
     coinbase_balance_after_mining_fee = get_account(
         block_env.state, block_env.coinbase
     ).balance + U256(transaction_fee)
-    if coinbase_balance_after_mining_fee != 0:
-        set_account_balance(
-            block_env.state,
-            block_env.coinbase,
-            coinbase_balance_after_mining_fee,
-        )
-    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
-        destroy_account(block_env.state, block_env.coinbase)
+    set_account_balance(
+        block_env.state,
+        block_env.coinbase,
+        coinbase_balance_after_mining_fee,
+    )
 
     for address in tx_output.accounts_to_delete:
         destroy_account(block_env.state, address)
@@ -1012,9 +1008,6 @@ def increase_recipient_balance(recipient: Account) -> None:
 
         modify_state(block_env.state, wd.address, increase_recipient_balance)
 
-        if account_exists_and_is_empty(block_env.state, wd.address):
-            destroy_account(block_env.state, wd.address)
-
 
 def check_gas_limit(gas_limit: Uint, parent_gas_limit: Uint) -> bool:
     """

src/ethereum/osaka/state.py

@@ -425,33 +425,6 @@ def account_has_storage(state: State, address: Address) -> bool:
     return address in state._storage_tries
 
 
-def account_exists_and_is_empty(state: State, address: Address) -> bool:
-    """
-    Checks if an account exists and has zero nonce, empty code and zero
-    balance.
-
-    Parameters
-    ----------
-    state:
-        The state
-    address:
-        Address of the account that needs to be checked.
-
-    Returns
-    -------
-    exists_and_is_empty : `bool`
-        True if an account exists and has zero nonce, empty code and zero
-        balance, False otherwise.
-    """
-    account = get_account_optional(state, address)
-    return (
-        account is not None
-        and account.nonce == Uint(0)
-        and account.code == b""
-        and account.balance == 0
-    )
-
-
 def is_account_alive(state: State, address: Address) -> bool:
     """
     Check whether is an account is both in the state and non empty.
@@ -476,10 +449,20 @@ def modify_state(
     state: State, address: Address, f: Callable[[Account], None]
 ) -> None:
     """
-    Modify an `Account` in the `State`.
+    Modify an `Account` in the `State`. If, after modification, the account
+    exists and has zero nonce, empty code, and zero balance, it is destroyed.
     """
     set_account(state, address, modify(get_account(state, address), f))
-    if account_exists_and_is_empty(state, address):
+
+    account = get_account_optional(state, address)
+    account_exists_and_is_empty = (
+        account is not None
+        and account.nonce == Uint(0)
+        and account.code == b""
+        and account.balance == 0
+    )
+
+    if account_exists_and_is_empty:
         destroy_account(state, address)
 
 

src/ethereum/paris/fork.py

@@ -39,7 +39,6 @@
 from .fork_types import Address
 from .state import (
     State,
-    account_exists_and_is_empty,
     destroy_account,
     get_account,
     increment_nonce,
@@ -578,14 +577,11 @@ def process_transaction(
     coinbase_balance_after_mining_fee = get_account(
         block_env.state, block_env.coinbase
     ).balance + U256(transaction_fee)
-    if coinbase_balance_after_mining_fee != 0:
-        set_account_balance(
-            block_env.state,
-            block_env.coinbase,
-            coinbase_balance_after_mining_fee,
-        )
-    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
-        destroy_account(block_env.state, block_env.coinbase)
+    set_account_balance(
+        block_env.state,
+        block_env.coinbase,
+        coinbase_balance_after_mining_fee,
+    )
 
     for address in tx_output.accounts_to_delete:
         destroy_account(block_env.state, address)

src/ethereum/paris/state.py

@@ -391,33 +391,6 @@ def account_has_storage(state: State, address: Address) -> bool:
     return address in state._storage_tries
 
 
-def account_exists_and_is_empty(state: State, address: Address) -> bool:
-    """
-    Checks if an account exists and has zero nonce, empty code and zero
-    balance.
-
-    Parameters
-    ----------
-    state:
-        The state
-    address:
-        Address of the account that needs to be checked.
-
-    Returns
-    -------
-    exists_and_is_empty : `bool`
-        True if an account exists and has zero nonce, empty code and zero
-        balance, False otherwise.
-    """
-    account = get_account_optional(state, address)
-    return (
-        account is not None
-        and account.nonce == Uint(0)
-        and account.code == b""
-        and account.balance == 0
-    )
-
-
 def is_account_alive(state: State, address: Address) -> bool:
     """
     Check whether is an account is both in the state and non empty.
@@ -442,10 +415,20 @@ def modify_state(
     state: State, address: Address, f: Callable[[Account], None]
 ) -> None:
     """
-    Modify an `Account` in the `State`.
+    Modify an `Account` in the `State`. If, after modification, the account
+    exists and has zero nonce, empty code, and zero balance, it is destroyed.
     """
     set_account(state, address, modify(get_account(state, address), f))
-    if account_exists_and_is_empty(state, address):
+
+    account = get_account_optional(state, address)
+    account_exists_and_is_empty = (
+        account is not None
+        and account.nonce == Uint(0)
+        and account.code == b""
+        and account.balance == 0
+    )
+
+    if account_exists_and_is_empty:
         destroy_account(state, address)
 
 

src/ethereum/prague/fork.py

@@ -53,7 +53,6 @@
 from .state import (
     State,
     TransientStorage,
-    account_exists_and_is_empty,
     destroy_account,
     get_account,
     increment_nonce,
@@ -945,14 +944,11 @@ def process_transaction(
     coinbase_balance_after_mining_fee = get_account(
         block_env.state, block_env.coinbase
     ).balance + U256(transaction_fee)
-    if coinbase_balance_after_mining_fee != 0:
-        set_account_balance(
-            block_env.state,
-            block_env.coinbase,
-            coinbase_balance_after_mining_fee,
-        )
-    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
-        destroy_account(block_env.state, block_env.coinbase)
+    set_account_balance(
+        block_env.state,
+        block_env.coinbase,
+        coinbase_balance_after_mining_fee,
+    )
 
     for address in tx_output.accounts_to_delete:
         destroy_account(block_env.state, address)
@@ -997,9 +993,6 @@ def increase_recipient_balance(recipient: Account) -> None:
 
         modify_state(block_env.state, wd.address, increase_recipient_balance)
 
-        if account_exists_and_is_empty(block_env.state, wd.address):
-            destroy_account(block_env.state, wd.address)
-
 
 def check_gas_limit(gas_limit: Uint, parent_gas_limit: Uint) -> bool:
     """

src/ethereum/prague/state.py

@@ -425,33 +425,6 @@ def account_has_storage(state: State, address: Address) -> bool:
     return address in state._storage_tries
 
 
-def account_exists_and_is_empty(state: State, address: Address) -> bool:
-    """
-    Checks if an account exists and has zero nonce, empty code and zero
-    balance.
-
-    Parameters
-    ----------
-    state:
-        The state
-    address:
-        Address of the account that needs to be checked.
-
-    Returns
-    -------
-    exists_and_is_empty : `bool`
-        True if an account exists and has zero nonce, empty code and zero
-        balance, False otherwise.
-    """
-    account = get_account_optional(state, address)
-    return (
-        account is not None
-        and account.nonce == Uint(0)
-        and account.code == b""
-        and account.balance == 0
-    )
-
-
 def is_account_alive(state: State, address: Address) -> bool:
     """
     Check whether is an account is both in the state and non empty.
@@ -476,10 +449,20 @@ def modify_state(
     state: State, address: Address, f: Callable[[Account], None]
 ) -> None:
     """
-    Modify an `Account` in the `State`.
+    Modify an `Account` in the `State`. If, after modification, the account
+    exists and has zero nonce, empty code, and zero balance, it is destroyed.
     """
     set_account(state, address, modify(get_account(state, address), f))
-    if account_exists_and_is_empty(state, address):
+
+    account = get_account_optional(state, address)
+    account_exists_and_is_empty = (
+        account is not None
+        and account.nonce == Uint(0)
+        and account.code == b""
+        and account.balance == 0
+    )
+
+    if account_exists_and_is_empty:
         destroy_account(state, address)