feat(tests): Add blob gas subtraction order tests (#407)

* feat(tests): Add blob gas subtraction order tests.

* feat(tests): Remove duplicate fixture within test_blob_txs.py

* feat(tests): Add max priority fee parameterization to blob gas subtraction tests.

* docs: Add changelog entry for blob gas subtraction test.

Author: spencer-tb

docs/CHANGELOG.md

@@ -8,6 +8,8 @@ Test fixtures for use by clients are available for each release on the [Github r
 
 ### 🧪 Test Cases
 
+- ✨ [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844): Adds `test_blob_gas_subtraction_tx()` verifying the blob gas fee is subtracted from the sender before executing the blob tx ([#407](https://github.com/ethereum/execution-spec-tests/pull/407)).
+
 ### 🛠️ Framework
 
 - 🐞 State tests generated with transition forks no longer use the transition fork name in the fixture output, instead they use the actual enabled fork according to the state test's block number and timestamp ([#406](https://github.com/ethereum/execution-spec-tests/pull/406)).

tests/cancun/eip4844_blobs/test_blob_txs.py

@@ -207,10 +207,33 @@ def total_account_minimum_balance(  # noqa: D103
     Calculates the minimum balance required for the account to be able to send
     the transactions in the block of the test.
     """
+    minimum_cost = 0
+    for tx_blob_count in [len(x) for x in blob_hashes_per_tx]:
+        blob_cost = tx_max_fee_per_blob_gas * Spec.GAS_PER_BLOB * tx_blob_count
+        minimum_cost += (tx_gas * tx_max_fee_per_gas) + tx_value + blob_cost
+    return minimum_cost
+
+
+@pytest.fixture
+def total_account_transactions_fee(  # noqa: D103
+    tx_gas: int,
+    tx_value: int,
+    blob_gasprice: int,
+    block_fee_per_gas: int,
+    tx_max_fee_per_gas: int,
+    tx_max_priority_fee_per_gas: int,
+    blob_hashes_per_tx: List[List[bytes]],
+) -> int:
+    """
+    Calculates the actual fee for the blob transactions in the block of the test.
+    """
     total_cost = 0
     for tx_blob_count in [len(x) for x in blob_hashes_per_tx]:
-        data_cost = tx_max_fee_per_blob_gas * Spec.GAS_PER_BLOB * tx_blob_count
-        total_cost += (tx_gas * tx_max_fee_per_gas) + tx_value + data_cost
+        blob_cost = blob_gasprice * Spec.GAS_PER_BLOB * tx_blob_count
+        block_producer_fee = (
+            tx_max_fee_per_gas - block_fee_per_gas if tx_max_priority_fee_per_gas else 0
+        )
+        total_cost += (tx_gas * (block_fee_per_gas + block_producer_fee)) + tx_value + blob_cost
     return total_cost
 
 
@@ -463,34 +486,17 @@ def header_verify(
     return header_verify
 
 
-@pytest.fixture
-def all_blob_gas_used(
-    fork: Fork,
-    txs: List[Transaction],
-    block_number: int,
-    block_timestamp: int,
-) -> Optional[int | Removable]:
-    """
-    Calculates the blob gas used by the test block taking into account failed transactions.
-    """
-    if not fork.header_blob_gas_used_required(
-        block_number=block_number, timestamp=block_timestamp
-    ):
-        return Header.EMPTY_FIELD
-    return sum([Spec.get_total_blob_gas(tx) for tx in txs])
-
-
 @pytest.fixture
 def rlp_modifier(
-    all_blob_gas_used: Optional[int | Removable],
+    expected_blob_gas_used: Optional[int | Removable],
 ) -> Optional[Header]:
     """
     Header fields to modify on the output block in the BlockchainTest.
     """
-    if all_blob_gas_used == Header.EMPTY_FIELD:
+    if expected_blob_gas_used == Header.EMPTY_FIELD:
         return None
     return Header(
-        blob_gas_used=all_blob_gas_used,
+        blob_gas_used=expected_blob_gas_used,
     )
 
 
@@ -896,6 +902,69 @@ def test_sufficient_balance_blob_tx_pre_fund_tx(
     )
 
 
+@pytest.mark.parametrize(
+    "tx_access_list",
+    [[], [AccessList(address=100, storage_keys=[100, 200])]],
+    ids=["no_access_list", "access_list"],
+)
+@pytest.mark.parametrize("tx_max_fee_per_gas", [7, 14])
+@pytest.mark.parametrize("tx_max_priority_fee_per_gas", [0, 7])
+@pytest.mark.parametrize("tx_value", [0, 1])
+@pytest.mark.parametrize(
+    "tx_calldata",
+    [b"", b"\x01"],
+    ids=["no_calldata", "single_non_zero_byte_calldata"],
+)
+@pytest.mark.parametrize("tx_max_fee_per_blob_gas", [1, 100])
+@pytest.mark.parametrize(
+    "tx_gas", [500_000], ids=[""]
+)  # Increase gas to account for contract code
+@pytest.mark.parametrize(
+    "mid_tx_send_amount", [100]
+)  # Amount sent by the contract to the sender mid execution
+@pytest.mark.valid_from("Cancun")
+def test_blob_gas_subtraction_tx(
+    state_test: StateTestFiller,
+    state_env: Environment,
+    pre: Dict,
+    txs: List[Transaction],
+    destination_account: str,
+    mid_tx_send_amount: int,
+    total_account_transactions_fee: int,
+):
+    """
+    Check that the blob gas fee for a transaction is subtracted from the sender balance before the
+    transaction is executed, including:
+
+    - Transactions with max fee equal or higher than current block base fee
+    - Transactions with and without value
+    - Transactions with and without calldata
+    - Transactions with max fee per blob gas lower or higher than the priority fee
+    - Transactions where an externally owned account sends funds to the sender mid execution
+    """
+    assert len(txs) == 1
+    pre[destination_account] = Account(
+        balance=mid_tx_send_amount,
+        code=Op.SSTORE(0, Op.BALANCE(Op.ORIGIN))
+        + Op.CALL(Op.GAS, Op.ORIGIN, mid_tx_send_amount, 0, 0, 0, 0)
+        + Op.SSTORE(1, Op.BALANCE(Op.ORIGIN)),
+    )
+    post = {
+        destination_account: Account(
+            storage={
+                0: pre[TestAddress].balance - total_account_transactions_fee,
+                1: pre[TestAddress].balance - total_account_transactions_fee + mid_tx_send_amount,
+            }
+        )
+    }
+    state_test(
+        pre=pre,
+        post=post,
+        tx=txs[0],
+        env=state_env,
+    )
+
+
 @pytest.mark.parametrize(
     "blobs_per_tx",
     all_valid_blob_combinations(),