feat(spec-specs, tests): EIP-8037 more refund fixes (ethereum#2823)

Co-authored-by: felipe <fselmo2@gmail.com>

Author: spencer-tb

src/ethereum/forks/amsterdam/fork.py

@@ -15,7 +15,7 @@
 from typing import List, Optional, Tuple
 
 from ethereum_rlp import rlp
-from ethereum_types.bytes import Bytes
+from ethereum_types.bytes import Bytes, Bytes0
 from ethereum_types.frozen import slotted_freezable
 from ethereum_types.numeric import U64, U256, Uint, ulen
 
@@ -1076,6 +1076,12 @@ def process_transaction(
     if tx_output.error is not None:
         tx_output.state_gas_left += tx_output.state_gas_used
         tx_output.state_gas_used = Uint(0)
+        if isinstance(tx.to, Bytes0):
+            new_account_refund = (
+                STATE_BYTES_PER_NEW_ACCOUNT * COST_PER_STATE_BYTE
+            )
+            tx_output.state_gas_left += new_account_refund
+            tx_output.state_refund += new_account_refund
     else:
         # Refund state gas for accounts created and destroyed in the
         # same tx (EIP-6780). Covers account, storage, and code.

src/ethereum/forks/amsterdam/vm/__init__.py

@@ -181,7 +181,6 @@ class Evm:
     accessed_storage_keys: Set[Tuple[Address, Bytes32]]
     regular_gas_used: Uint = Uint(0)
     state_gas_used: Uint = Uint(0)
-    state_gas_refund: Uint = Uint(0)
     state_gas_refund_pending: Uint = Uint(0)
 
 
@@ -191,10 +190,8 @@ def credit_state_gas_refund(evm: Evm, amount: Uint) -> None:
 
     Clamp the applied portion to this frame's `state_gas_used` — the
     matching charge may sit in an ancestor sharing storage via
-    CALLCODE/DELEGATECALL.  Track it in `state_gas_refund` so
-    `incorporate_child_on_error` can undo the inflation, and defer the
-    unapplied remainder in `state_gas_refund_pending` for propagation
-    on success.
+    CALLCODE/DELEGATECALL.  Defer the unapplied remainder in
+    `state_gas_refund_pending` for propagation on success.
 
     Parameters
     ----------
@@ -207,18 +204,16 @@ def credit_state_gas_refund(evm: Evm, amount: Uint) -> None:
     applied = min(amount, evm.state_gas_used)
     evm.state_gas_left += applied
     evm.state_gas_used -= applied
-    evm.state_gas_refund += applied
     evm.state_gas_refund_pending += amount - applied
 
 
 def incorporate_child_on_success(evm: Evm, child_evm: Evm) -> None:
     """
     Incorporate the state of a successful `child_evm` into the parent `evm`.
 
-    Propagate `state_gas_refund` (inline credits the child applied) so
-    an ancestor revert can undo the inflation, and apply
-    `state_gas_refund_pending` (the unapplied remainder) to the parent
-    via `credit_state_gas_refund`; any leftover propagates further up.
+    Apply `state_gas_refund_pending` (the unapplied remainder of any
+    refund credited inside the child) to the parent via
+    `credit_state_gas_refund`; any leftover propagates further up.
 
     Parameters
     ----------
@@ -237,7 +232,6 @@ def incorporate_child_on_success(evm: Evm, child_evm: Evm) -> None:
     evm.accessed_storage_keys.update(child_evm.accessed_storage_keys)
     evm.regular_gas_used += child_evm.regular_gas_used
     evm.state_gas_used += child_evm.state_gas_used
-    evm.state_gas_refund += child_evm.state_gas_refund
     credit_state_gas_refund(evm, child_evm.state_gas_refund_pending)
 
 
@@ -253,11 +247,11 @@ def incorporate_child_on_error(
     that spilled into `gas_left`, is restored to the parent's reservoir and
     the child's `state_gas_used` is not accumulated.
 
-    Inline state-gas refunds (SSTORE 0 to x to 0, CREATE silent failure)
-    credited by the child inflated its `state_gas_left`; subtract
-    `state_gas_refund` from the amount returned to the parent's
-    reservoir so the inflation does not leak across the error boundary.
-    `state_gas_refund_pending` is discarded with the child frame.
+    `state_gas_refund_pending` is discarded with the child frame: any
+    inline credits the child applied are keyed to charges (its own
+    SSTORE or CREATE pre-charge) that are themselves rolled back, so
+    the matching `state_gas_left + state_gas_used` sum already reflects
+    the correct amount to return to the parent.
 
     Parameters
     ----------
@@ -268,11 +262,7 @@ def incorporate_child_on_error(
 
     """
     evm.gas_left += child_evm.gas_left
-    evm.state_gas_left += (
-        child_evm.state_gas_used
-        + child_evm.state_gas_left
-        - child_evm.state_gas_refund
-    )
+    evm.state_gas_left += child_evm.state_gas_used + child_evm.state_gas_left
     evm.regular_gas_used += child_evm.regular_gas_used
 
 

tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_create.py

@@ -1844,15 +1844,16 @@ def test_create_code_deposit_oog_refunds_state_gas(
     ],
 )
 @pytest.mark.valid_from("EIP8037")
-def test_failed_create_tx_state_gas_dominates(
+def test_failed_create_tx_refunds_intrinsic_new_account(
     blockchain_test: BlockchainTestFiller,
     pre: Alloc,
     fork: Fork,
     init_code: Bytecode,
 ) -> None:
     """
-    Verify the header gas is set by intrinsic state gas when a
-    creation tx fails with a tight regular budget.
+    Verify the NEW_ACCOUNT × CPSB portion of intrinsic_state_gas is
+    refunded on creation-tx revert/halt, so block state-gas excludes
+    it and header gas_used reflects only the regular component.
     """
     intrinsic_calc = fork.transaction_intrinsic_cost_calculator()
     create_state_gas = fork.create_state_gas(code_size=0)
@@ -1863,9 +1864,12 @@ def test_failed_create_tx_state_gas_dominates(
     intrinsic_regular = intrinsic_total - create_state_gas
     gas_limit = intrinsic_total + 1000
 
-    assert intrinsic_regular + 1000 < create_state_gas, (
-        "tight gas budget must keep block_regular below create_state_gas"
-    )
+    if init_code == Op.INVALID:
+        regular_consumed = gas_limit - intrinsic_total
+    else:
+        regular_consumed = init_code.regular_cost(fork)
+
+    expected_gas_used = intrinsic_regular + regular_consumed
 
     tx = Transaction(
         to=None,
@@ -1879,7 +1883,54 @@ def test_failed_create_tx_state_gas_dominates(
         blocks=[
             Block(
                 txs=[tx],
-                header_verify=Header(gas_used=create_state_gas),
+                header_verify=Header(gas_used=expected_gas_used),
+            ),
+        ],
+        post={},
+    )
+
+
+@pytest.mark.pre_alloc_mutable()
+@pytest.mark.valid_from("EIP8037")
+def test_create_tx_collision_refunds_intrinsic_new_account(
+    blockchain_test: BlockchainTestFiller,
+    pre: Alloc,
+    fork: Fork,
+) -> None:
+    """
+    Verify the NEW_ACCOUNT × CPSB portion of intrinsic_state_gas is
+    refunded on creation-tx address collision, so block state-gas
+    excludes it and header gas_used reflects only the regular
+    consumption (full forwarded gas, no initcode runs).
+    """
+    intrinsic_calc = fork.transaction_intrinsic_cost_calculator()
+    create_state_gas = fork.create_state_gas(code_size=0)
+
+    init_code = Op.STOP
+    intrinsic_total = intrinsic_calc(
+        calldata=bytes(init_code), contract_creation=True
+    )
+    gas_limit = intrinsic_total + 1000
+
+    sender = pre.fund_eoa()
+    collision_target = compute_create_address(address=sender, nonce=0)
+    pre[collision_target] = Account(nonce=1)
+
+    expected_gas_used = gas_limit - create_state_gas
+
+    tx = Transaction(
+        to=None,
+        data=init_code,
+        gas_limit=gas_limit,
+        sender=sender,
+    )
+
+    blockchain_test(
+        pre=pre,
+        blocks=[
+            Block(
+                txs=[tx],
+                header_verify=Header(gas_used=expected_gas_used),
             ),
         ],
         post={},
@@ -2131,11 +2182,6 @@ def test_inner_create_succeeds_code_deposit_state_gas(
         initcode_gas = initcode.gas_cost(fork)
     gas_limit = intrinsic_total + initcode_gas + inner_code_deposit + 1000
 
-    if outer_outcome == "succeeds":
-        expected_state = outer_state_gas + inner_state_gas
-    else:
-        expected_state = outer_state_gas
-
     create_address = compute_create_address(address=sender, nonce=0)
 
     tx = Transaction(
@@ -2147,19 +2193,15 @@ def test_inner_create_succeeds_code_deposit_state_gas(
 
     if outer_outcome == "succeeds":
         post: dict = {create_address: Account(code=b"")}
+        block = Block(
+            txs=[tx],
+            header_verify=Header(gas_used=outer_state_gas + inner_state_gas),
+        )
     else:
         post = {create_address: Account.NONEXISTENT}
+        block = Block(txs=[tx])
 
-    blockchain_test(
-        pre=pre,
-        blocks=[
-            Block(
-                txs=[tx],
-                header_verify=Header(gas_used=expected_state),
-            ),
-        ],
-        post=post,
-    )
+    blockchain_test(pre=pre, blocks=[block], post=post)
 
 
 @pytest.mark.parametrize(
@@ -2355,8 +2397,6 @@ def test_inner_create_fail_refunds_in_creation_tx(
         + num_inner_ops * (gas_costs.NEW_ACCOUNT + per_inner_slack)
     )
 
-    expected_state = outer_state_gas
-
     create_address = compute_create_address(address=sender, nonce=0)
 
     tx = Transaction(
@@ -2368,19 +2408,15 @@ def test_inner_create_fail_refunds_in_creation_tx(
 
     if outer_outcome == "succeeds":
         post: dict = {create_address: Account(code=b"")}
+        block = Block(
+            txs=[tx],
+            header_verify=Header(gas_used=outer_state_gas),
+        )
     else:
         post = {create_address: Account.NONEXISTENT}
+        block = Block(txs=[tx])
 
-    blockchain_test(
-        pre=pre,
-        blocks=[
-            Block(
-                txs=[tx],
-                header_verify=Header(gas_used=expected_state),
-            ),
-        ],
-        post=post,
-    )
+    blockchain_test(pre=pre, blocks=[block], post=post)
 
 
 @pytest.mark.pre_alloc_mutable