add error messages to traces (#846)

* add error messages to traces

* include review comments

* combine has_erred and error in Evm

Author: gurukamath

src/ethereum/arrow_glacier/fork.py

@@ -442,7 +442,7 @@ def check_transaction(
 
 def make_receipt(
     tx: Transaction,
-    has_erred: bool,
+    error: Optional[Exception],
     cumulative_gas_used: Uint,
     logs: Tuple[Log, ...],
 ) -> Union[Bytes, Receipt]:
@@ -453,8 +453,8 @@ def make_receipt(
     ----------
     tx :
         The executed transaction.
-    has_erred :
-        Whether the top level frame of the transaction exited with an error.
+    error :
+        Error in the top level frame of the transaction, if any.
     cumulative_gas_used :
         The total gas used so far in the block after the transaction was
         executed.
@@ -467,7 +467,7 @@ def make_receipt(
         The receipt for the transaction.
     """
     receipt = Receipt(
-        succeeded=not has_erred,
+        succeeded=error is None,
         cumulative_gas_used=cumulative_gas_used,
         bloom=logs_bloom(logs),
         logs=logs,
@@ -579,11 +579,11 @@ def apply_body(
             traces=[],
         )
 
-        gas_used, logs, has_erred = process_transaction(env, tx)
+        gas_used, logs, error = process_transaction(env, tx)
         gas_available -= gas_used
 
         receipt = make_receipt(
-            tx, has_erred, (block_gas_limit - gas_available), logs
+            tx, error, (block_gas_limit - gas_available), logs
         )
 
         trie_set(
@@ -732,7 +732,7 @@ def pay_rewards(
 
 def process_transaction(
     env: vm.Environment, tx: Transaction
-) -> Tuple[Uint, Tuple[Log, ...], bool]:
+) -> Tuple[Uint, Tuple[Log, ...], Optional[Exception]]:
     """
     Execute a transaction against the provided environment.
 
@@ -838,7 +838,7 @@ def process_transaction(
         if account_exists_and_is_empty(env.state, address):
             destroy_account(env.state, address)
 
-    return total_gas_used, output.logs, output.has_erred
+    return total_gas_used, output.logs, output.error
 
 
 def validate_transaction(tx: Transaction) -> bool:

src/ethereum/arrow_glacier/vm/__init__.py

@@ -87,7 +87,6 @@ class Evm:
     output: Bytes
     accounts_to_delete: Set[Address]
     touched_accounts: Set[Address]
-    has_erred: bool
     return_data: Bytes
     error: Optional[Exception]
     accessed_addresses: Set[Address]

src/ethereum/arrow_glacier/vm/exceptions.py

@@ -118,3 +118,11 @@ class InvalidContractPrefix(ExceptionalHalt):
     """
 
     pass
+
+
+class AddressCollision(ExceptionalHalt):
+    """
+    Raised when the new contract address has a collision.
+    """
+
+    pass

src/ethereum/arrow_glacier/vm/instructions/system.py

@@ -118,7 +118,7 @@ def generic_create(
     )
     child_evm = process_create_message(child_message, evm.env)
 
-    if child_evm.has_erred:
+    if child_evm.error:
         incorporate_child_on_error(evm, child_evm)
         evm.return_data = child_evm.output
         push(evm.stack, U256(0))
@@ -288,7 +288,7 @@ def generic_call(
     )
     child_evm = process_message(child_message, evm.env)
 
-    if child_evm.has_erred:
+    if child_evm.error:
         incorporate_child_on_error(evm, child_evm)
         evm.return_data = child_evm.output
         push(evm.stack, U256(0))

src/ethereum/arrow_glacier/vm/interpreter.py

@@ -12,7 +12,7 @@
 A straightforward interpreter that executes EVM code.
 """
 from dataclasses import dataclass
-from typing import Iterable, Set, Tuple
+from typing import Iterable, Optional, Set, Tuple
 
 from ethereum.base_types import U256, Bytes0, Uint
 from ethereum.trace import (
@@ -46,6 +46,7 @@
 from ..vm.precompiled_contracts.mapping import PRE_COMPILED_CONTRACTS
 from . import Environment, Evm
 from .exceptions import (
+    AddressCollision,
     ExceptionalHalt,
     InvalidContractPrefix,
     InvalidOpcode,
@@ -72,15 +73,15 @@ class MessageCallOutput:
           3. `logs`: list of `Log` generated during execution.
           4. `accounts_to_delete`: Contracts which have self-destructed.
           5. `touched_accounts`: Accounts that have been touched.
-          6. `has_erred`: True if execution has caused an error.
+          6. `error`: The error from the execution if any.
     """
 
     gas_left: Uint
     refund_counter: U256
     logs: Tuple[Log, ...]
     accounts_to_delete: Set[Address]
     touched_accounts: Iterable[Address]
-    has_erred: bool
+    error: Optional[Exception]
 
 
 def process_message_call(
@@ -109,7 +110,7 @@ def process_message_call(
         )
         if is_collision:
             return MessageCallOutput(
-                Uint(0), U256(0), tuple(), set(), set(), True
+                Uint(0), U256(0), tuple(), set(), set(), AddressCollision()
             )
         else:
             evm = process_create_message(message, env)
@@ -118,7 +119,7 @@ def process_message_call(
         if account_exists_and_is_empty(env.state, Address(message.target)):
             evm.touched_accounts.add(Address(message.target))
 
-    if evm.has_erred:
+    if evm.error:
         logs: Tuple[Log, ...] = ()
         accounts_to_delete = set()
         touched_accounts = set()
@@ -129,9 +130,7 @@ def process_message_call(
         touched_accounts = evm.touched_accounts
         refund_counter = U256(evm.refund_counter)
 
-    tx_end = TransactionEnd(
-        message.gas - evm.gas_left, evm.output, evm.has_erred
-    )
+    tx_end = TransactionEnd(message.gas - evm.gas_left, evm.output, evm.error)
     evm_trace(evm, tx_end)
 
     return MessageCallOutput(
@@ -140,7 +139,7 @@ def process_message_call(
         logs=logs,
         accounts_to_delete=accounts_to_delete,
         touched_accounts=touched_accounts,
-        has_erred=evm.has_erred,
+        error=evm.error,
     )
 
 
@@ -179,19 +178,19 @@ def process_create_message(message: Message, env: Environment) -> Evm:
 
     increment_nonce(env.state, message.current_target)
     evm = process_message(message, env)
-    if not evm.has_erred:
+    if not evm.error:
         contract_code = evm.output
         contract_code_gas = len(contract_code) * GAS_CODE_DEPOSIT
         try:
             if len(contract_code) > 0:
                 ensure(contract_code[0] != 0xEF, InvalidContractPrefix)
             charge_gas(evm, contract_code_gas)
             ensure(len(contract_code) <= MAX_CODE_SIZE, OutOfGasError)
-        except ExceptionalHalt:
+        except ExceptionalHalt as error:
             rollback_transaction(env.state)
             evm.gas_left = Uint(0)
             evm.output = b""
-            evm.has_erred = True
+            evm.error = error
         else:
             set_code(env.state, message.current_target, contract_code)
             commit_transaction(env.state)
@@ -230,7 +229,7 @@ def process_message(message: Message, env: Environment) -> Evm:
         )
 
     evm = execute_code(message, env)
-    if evm.has_erred:
+    if evm.error:
         # revert state to the last saved checkpoint
         # since the message call resulted in an error
         rollback_transaction(env.state)
@@ -273,7 +272,6 @@ def execute_code(message: Message, env: Environment) -> Evm:
         output=b"",
         accounts_to_delete=set(),
         touched_accounts=set(),
-        has_erred=False,
         return_data=b"",
         error=None,
         accessed_addresses=message.accessed_addresses,
@@ -299,13 +297,12 @@ def execute_code(message: Message, env: Environment) -> Evm:
 
         evm_trace(evm, EvmStop(Ops.STOP))
 
-    except ExceptionalHalt:
-        evm_trace(evm, OpException())
+    except ExceptionalHalt as error:
+        evm_trace(evm, OpException(error))
         evm.gas_left = Uint(0)
         evm.output = b""
-        evm.has_erred = True
-    except Revert as e:
-        evm_trace(evm, OpException())
-        evm.error = e
-        evm.has_erred = True
+        evm.error = error
+    except Revert as error:
+        evm_trace(evm, OpException(error))
+        evm.error = error
     return evm

src/ethereum/berlin/fork.py

@@ -347,7 +347,7 @@ def check_transaction(
 
 def make_receipt(
     tx: Transaction,
-    has_erred: bool,
+    error: Optional[Exception],
     cumulative_gas_used: Uint,
     logs: Tuple[Log, ...],
 ) -> Union[Bytes, Receipt]:
@@ -358,8 +358,8 @@ def make_receipt(
     ----------
     tx :
         The executed transaction.
-    has_erred :
-        Whether the top level frame of the transaction exited with an error.
+    error :
+        Error in the top level frame of the transaction, if any.
     cumulative_gas_used :
         The total gas used so far in the block after the transaction was
         executed.
@@ -372,7 +372,7 @@ def make_receipt(
         The receipt for the transaction.
     """
     receipt = Receipt(
-        succeeded=not has_erred,
+        succeeded=error is None,
         cumulative_gas_used=cumulative_gas_used,
         bloom=logs_bloom(logs),
         logs=logs,
@@ -476,11 +476,11 @@ def apply_body(
             traces=[],
         )
 
-        gas_used, logs, has_erred = process_transaction(env, tx)
+        gas_used, logs, error = process_transaction(env, tx)
         gas_available -= gas_used
 
         receipt = make_receipt(
-            tx, has_erred, (block_gas_limit - gas_available), logs
+            tx, error, (block_gas_limit - gas_available), logs
         )
 
         trie_set(
@@ -629,7 +629,7 @@ def pay_rewards(
 
 def process_transaction(
     env: vm.Environment, tx: Transaction
-) -> Tuple[Uint, Tuple[Log, ...], bool]:
+) -> Tuple[Uint, Tuple[Log, ...], Optional[Exception]]:
     """
     Execute a transaction against the provided environment.
 
@@ -721,7 +721,7 @@ def process_transaction(
         if account_exists_and_is_empty(env.state, address):
             destroy_account(env.state, address)
 
-    return total_gas_used, output.logs, output.has_erred
+    return total_gas_used, output.logs, output.error
 
 
 def validate_transaction(tx: Transaction) -> bool:

src/ethereum/berlin/vm/__init__.py

@@ -86,7 +86,6 @@ class Evm:
     output: Bytes
     accounts_to_delete: Set[Address]
     touched_accounts: Set[Address]
-    has_erred: bool
     return_data: Bytes
     error: Optional[Exception]
     accessed_addresses: Set[Address]

src/ethereum/berlin/vm/exceptions.py

@@ -110,3 +110,11 @@ class InvalidParameter(ExceptionalHalt):
     """
 
     pass
+
+
+class AddressCollision(ExceptionalHalt):
+    """
+    Raised when the new contract address has a collision.
+    """
+
+    pass

src/ethereum/berlin/vm/instructions/system.py

@@ -119,7 +119,7 @@ def generic_create(
     )
     child_evm = process_create_message(child_message, evm.env)
 
-    if child_evm.has_erred:
+    if child_evm.error:
         incorporate_child_on_error(evm, child_evm)
         evm.return_data = child_evm.output
         push(evm.stack, U256(0))
@@ -289,7 +289,7 @@ def generic_call(
     )
     child_evm = process_message(child_message, evm.env)
 
-    if child_evm.has_erred:
+    if child_evm.error:
         incorporate_child_on_error(evm, child_evm)
         evm.return_data = child_evm.output
         push(evm.stack, U256(0))