feat(tests): port ethereum/tests swap opcode tests

tests/frontier/opcodes/test_swap.py

@@ -0,0 +1,129 @@
+"""
+A State test for the set of `SWAP*` opcodes.
+Ported from: https://github.com/ethereum/tests/
+blob/develop/src/GeneralStateTestsFiller/VMTests/vmTests/swapFiller.yml.
+"""
+
+import pytest  # noqa: I001
+
+from ethereum_test_forks import Fork, Frontier, Homestead
+from ethereum_test_tools import Account, Alloc, Bytecode, Environment
+from ethereum_test_tools import Opcodes as Op
+from ethereum_test_tools import StateTestFiller, Storage, Transaction
+
+
+@pytest.mark.parametrize(
+    "swap_opcode",
+    [getattr(Op, f"SWAP{i}") for i in range(1, 17)],
+    ids=lambda op: str(op),
+)
+@pytest.mark.valid_from("Frontier")
+def test_swap(
+    state_test: StateTestFiller,
+    fork: Fork,
+    pre: Alloc,
+    swap_opcode: Op
+):
+    """
+    The set of `SWAP*` opcodes swaps the top of the stack with a specific
+    element.
+
+    In this test, we ensure that the set of `SWAP*` opcodes correctly swaps
+    the top element with the nth element and stores the result in storage.
+    """
+    env = Environment()
+
+    # Calculate which position we're swapping with (1-based index)
+    swap_pos = swap_opcode.int() - 0x90 + 1
+
+    # Generate stack values
+    stack_values = list(range(swap_pos + 1))
+
+    # Push the stack values onto the stack (in reverse order).
+    contract_code = Bytecode()
+    for value in reversed(stack_values):
+        contract_code += Op.PUSH1(value)
+
+    # Perform the SWAP operation.
+    contract_code += swap_opcode
+
+    # Store the top of the stack in storage slot 0.
+    contract_code += Op.PUSH1(0) + Op.SSTORE
+
+    # Deploy the contract with the generated bytecode.
+    contract = pre.deploy_contract(contract_code)
+
+    # Create a transaction to execute the contract.
+    tx = Transaction(
+        sender=pre.fund_eoa(),
+        to=contract,
+        gas_limit=500_000,
+        protected=False if fork in [Frontier, Homestead] else True,
+    )
+
+    # After SWAP, the top value will be the one at swap_pos
+    expected_value = swap_pos
+
+    # Define the expected post-state.
+    post = {}
+    storage = Storage()
+    storage.store_next(expected_value, f"SWAP{swap_pos} result")
+    post[contract] = Account(storage=storage)
+    # Run the state test.
+    state_test(env=env, pre=pre, post=post, tx=tx)
+
+
+@pytest.mark.parametrize(
+    "swap_opcode",
+    [getattr(Op, f"SWAP{i}") for i in range(1, 17)],
+    ids=lambda op: str(op),
+)
+@pytest.mark.valid_from("Frontier")
+def test_stack_underflow(
+    state_test: StateTestFiller,
+    fork: Fork,
+    pre: Alloc,
+    swap_opcode: Op,
+):
+    """
+    A test to ensure that the stack underflow when there are not enough
+    elements for the `SWAP*` opcode to operate.
+
+    For each SWAPn operation, we push exactly (n-1) elements to cause an
+    underflow when trying to swap with the nth element.
+    """
+    env = Environment()
+
+    # Calculate which position we're swapping with (1-based index)
+    swap_pos = swap_opcode.int() - 0x90 + 1
+
+    # Push exactly (n-1) elements for SWAPn to cause underflow
+    contract_code = Bytecode()
+    for i in range(swap_pos - 1):
+        contract_code += Op.PUSH1(i % 256)
+
+    # Attempt to perform the SWAP operation
+    contract_code += swap_opcode
+
+    # Store the top of the stack in storage slot 0
+    contract_code += Op.PUSH1(0) + Op.SSTORE
+
+    # Deploy the contract with the generated bytecode.
+    contract = pre.deploy_contract(contract_code)
+
+    # Create a transaction to execute the contract.
+    tx = Transaction(
+        sender=pre.fund_eoa(),
+        to=contract,
+        gas_limit=500_000,
+        protected=False if fork in [Frontier, Homestead] else True,
+    )
+
+    # Define the expected post-state.
+    post = {}
+    storage = Storage()
+    storage.store_next(0, f"SWAP{swap_pos} failed due to stack underflow")
+    post[contract] = Account(storage=storage)
+
+    # Run the state test.
+    state_test(env=env, pre=pre, post=post, tx=tx)