Testing with Ethereum Tester¶
Ethereum Tester is a tool suite for testing Ethereum based applications.
This section provides a quick overview of testing with eth-tester
. To learn more, you can view the documentation at the Github repo or join the Gitter channel.
Getting Started¶
Prior to testing, the Vyper specific contract conversion and the blockchain related fixtures need to be set up. These fixtures will be used in every test file and should therefore be defined in conftest.py.
Note
Since the testing is done in the pytest framework, you can make use of pytest.ini, tox.ini and setup.cfg and you can use most IDEs’ pytest plugins.
1import json
2import logging
3from contextlib import contextmanager
4from functools import wraps
5
6import hypothesis
7import pytest
8import web3.exceptions
9from eth_tester import EthereumTester, PyEVMBackend
10from eth_tester.exceptions import TransactionFailed
11from eth_utils import setup_DEBUG2_logging
12from eth_utils.toolz import compose
13from hexbytes import HexBytes
14from web3 import Web3
15from web3.contract import Contract
16from web3.providers.eth_tester import EthereumTesterProvider
17
18import vyper.evm.opcodes as evm
19from tests.utils import working_directory
20from vyper import compiler
21from vyper.ast.grammar import parse_vyper_source
22from vyper.codegen.ir_node import IRnode
23from vyper.compiler.input_bundle import FilesystemInputBundle, InputBundle
24from vyper.compiler.settings import OptimizationLevel, Settings, _set_debug_mode
25from vyper.ir import compile_ir, optimizer
26from vyper.utils import ERC5202_PREFIX
27
28# Import the base fixtures
29pytest_plugins = ["tests.fixtures.memorymock"]
30
31############
32# PATCHING #
33############
34
35
36# disable hypothesis deadline globally
37hypothesis.settings.register_profile("ci", deadline=None)
38hypothesis.settings.load_profile("ci")
39
40
41def set_evm_verbose_logging():
42 logger = logging.getLogger("eth.vm.computation.BaseComputation")
43 setup_DEBUG2_logging()
44 logger.setLevel("DEBUG2")
45
46
47# Useful options to comment out whilst working:
48# set_evm_verbose_logging()
49#
50# from vdb import vdb
51# vdb.set_evm_opcode_debugger()
52
53
54def pytest_addoption(parser):
55 parser.addoption(
56 "--optimize",
57 choices=["codesize", "gas", "none"],
58 default="gas",
59 help="change optimization mode",
60 )
61 parser.addoption("--enable-compiler-debug-mode", action="store_true")
62
63 parser.addoption(
64 "--evm-version",
65 choices=list(evm.EVM_VERSIONS.keys()),
66 default="shanghai",
67 help="set evm version",
68 )
69
70
71@pytest.fixture(scope="module")
72def output_formats():
73 output_formats = compiler.OUTPUT_FORMATS.copy()
74 del output_formats["bb"]
75 del output_formats["bb_runtime"]
76 return output_formats
77
78
79@pytest.fixture(scope="module")
80def optimize(pytestconfig):
81 flag = pytestconfig.getoption("optimize")
82 return OptimizationLevel.from_string(flag)
83
84
85@pytest.fixture(scope="session", autouse=True)
86def debug(pytestconfig):
87 debug = pytestconfig.getoption("enable_compiler_debug_mode")
88 assert isinstance(debug, bool)
89 _set_debug_mode(debug)
90
91
92@pytest.fixture(scope="session", autouse=True)
93def evm_version(pytestconfig):
94 # note: we configure the evm version that we emit code for,
95 # but eth-tester is only configured with the latest mainnet
96 # version.
97 evm_version_str = pytestconfig.getoption("evm_version")
98 evm.DEFAULT_EVM_VERSION = evm_version_str
99 # this should get overridden by anchor_evm_version,
100 # but set it anyway
101 evm.active_evm_version = evm.EVM_VERSIONS[evm_version_str]
102
103
104@pytest.fixture
105def chdir_tmp_path(tmp_path):
106 # this is useful for when you want imports to have relpaths
107 with working_directory(tmp_path):
108 yield
109
110
111@pytest.fixture
112def keccak():
113 return Web3.keccak
114
115
116@pytest.fixture
117def make_file(tmp_path):
118 # writes file_contents to file_name, creating it in the
119 # tmp_path directory. returns final path.
120 def fn(file_name, file_contents):
121 path = tmp_path / file_name
122 path.parent.mkdir(parents=True, exist_ok=True)
123 with path.open("w") as f:
124 f.write(file_contents)
125
126 return path
127
128 return fn
129
130
131# this can either be used for its side effects (to prepare a call
132# to get_contract), or the result can be provided directly to
133# compile_code / CompilerData.
134@pytest.fixture
135def make_input_bundle(tmp_path, make_file):
136 def fn(sources_dict):
137 for file_name, file_contents in sources_dict.items():
138 make_file(file_name, file_contents)
139 return FilesystemInputBundle([tmp_path])
140
141 return fn
142
143
144# for tests which just need an input bundle, doesn't matter what it is
145@pytest.fixture
146def dummy_input_bundle():
147 return InputBundle([])
148
149
150# TODO: remove me, this is just string.encode("utf-8").ljust()
151# only used in test_logging.py.
152@pytest.fixture
153def bytes_helper():
154 def bytes_helper(str, length):
155 return bytes(str, "utf-8") + bytearray(length - len(str))
156
157 return bytes_helper
158
159
160def _none_addr(datatype, data):
161 if datatype == "address" and int(data, base=16) == 0:
162 return (datatype, None)
163 else:
164 return (datatype, data)
165
166
167CONCISE_NORMALIZERS = (_none_addr,)
168
169
170@pytest.fixture(scope="module")
171def tester():
172 # set absurdly high gas limit so that london basefee never adjusts
173 # (note: 2**63 - 1 is max that evm allows)
174 custom_genesis = PyEVMBackend._generate_genesis_params(overrides={"gas_limit": 10**10})
175 custom_genesis["base_fee_per_gas"] = 0
176 backend = PyEVMBackend(genesis_parameters=custom_genesis)
177 return EthereumTester(backend=backend)
178
179
180def zero_gas_price_strategy(web3, transaction_params=None):
181 return 0 # zero gas price makes testing simpler.
182
183
184@pytest.fixture(scope="module")
185def w3(tester):
186 w3 = Web3(EthereumTesterProvider(tester))
187 w3.eth.set_gas_price_strategy(zero_gas_price_strategy)
188 return w3
189
190
191def get_compiler_gas_estimate(code, func):
192 sigs = compiler.phases.CompilerData(code).function_signatures
193 if func:
194 return compiler.utils.build_gas_estimates(sigs)[func] + 22000
195 else:
196 return sum(compiler.utils.build_gas_estimates(sigs).values()) + 22000
197
198
199def check_gas_on_chain(w3, tester, code, func=None, res=None):
200 gas_estimate = get_compiler_gas_estimate(code, func)
201 gas_actual = tester.get_block_by_number("latest")["gas_used"]
202 # Computed upper bound on the gas consumption should
203 # be greater than or equal to the amount of gas used
204 if gas_estimate < gas_actual:
205 raise Exception(f"Gas upper bound fail: bound {gas_estimate} actual {gas_actual}")
206
207 print(f"Function name: {func} - Gas estimate {gas_estimate}, Actual: {gas_actual}")
208
209
210def gas_estimation_decorator(w3, tester, fn, source_code, func):
211 def decorator(*args, **kwargs):
212 @wraps(fn)
213 def decorated_function(*args, **kwargs):
214 result = fn(*args, **kwargs)
215 if "transact" in kwargs:
216 check_gas_on_chain(w3, tester, source_code, func, res=result)
217 return result
218
219 return decorated_function(*args, **kwargs)
220
221 return decorator
222
223
224def set_decorator_to_contract_function(w3, tester, contract, source_code, func):
225 func_definition = getattr(contract, func)
226 func_with_decorator = gas_estimation_decorator(w3, tester, func_definition, source_code, func)
227 setattr(contract, func, func_with_decorator)
228
229
230class VyperMethod:
231 ALLOWED_MODIFIERS = {"call", "estimateGas", "transact", "buildTransaction"}
232
233 def __init__(self, function, normalizers=None):
234 self._function = function
235 self._function._return_data_normalizers = normalizers
236
237 def __call__(self, *args, **kwargs):
238 return self.__prepared_function(*args, **kwargs)
239
240 def __prepared_function(self, *args, **kwargs):
241 if not kwargs:
242 modifier, modifier_dict = "call", {}
243 fn_abi = [
244 x
245 for x in self._function.contract_abi
246 if x.get("name") == self._function.function_identifier
247 ].pop()
248 # To make tests faster just supply some high gas value.
249 modifier_dict.update({"gas": fn_abi.get("gas", 0) + 500000})
250 elif len(kwargs) == 1:
251 modifier, modifier_dict = kwargs.popitem()
252 if modifier not in self.ALLOWED_MODIFIERS:
253 raise TypeError(f"The only allowed keyword arguments are: {self.ALLOWED_MODIFIERS}")
254 else:
255 raise TypeError(f"Use up to one keyword argument, one of: {self.ALLOWED_MODIFIERS}")
256 return getattr(self._function(*args), modifier)(modifier_dict)
257
258
259class VyperContract:
260 """
261 An alternative Contract Factory which invokes all methods as `call()`,
262 unless you add a keyword argument. The keyword argument assigns the prep method.
263 This call
264 > contract.withdraw(amount, transact={'from': eth.accounts[1], 'gas': 100000, ...})
265 is equivalent to this call in the classic contract:
266 > contract.functions.withdraw(amount).transact({'from': eth.accounts[1], 'gas': 100000, ...})
267 """
268
269 def __init__(self, classic_contract, method_class=VyperMethod):
270 classic_contract._return_data_normalizers += CONCISE_NORMALIZERS
271 self._classic_contract = classic_contract
272 self.address = self._classic_contract.address
273 protected_fn_names = [fn for fn in dir(self) if not fn.endswith("__")]
274
275 try:
276 fn_names = [fn["name"] for fn in self._classic_contract.functions._functions]
277 except web3.exceptions.NoABIFunctionsFound:
278 fn_names = []
279
280 for fn_name in fn_names:
281 # Override namespace collisions
282 if fn_name in protected_fn_names:
283 raise AttributeError(f"{fn_name} is protected!")
284 else:
285 _classic_method = getattr(self._classic_contract.functions, fn_name)
286 _concise_method = method_class(
287 _classic_method, self._classic_contract._return_data_normalizers
288 )
289 setattr(self, fn_name, _concise_method)
290
291 @classmethod
292 def factory(cls, *args, **kwargs):
293 return compose(cls, Contract.factory(*args, **kwargs))
294
295
296@pytest.fixture
297def get_contract_from_ir(w3, optimize):
298 def ir_compiler(ir, *args, **kwargs):
299 ir = IRnode.from_list(ir)
300 if optimize != OptimizationLevel.NONE:
301 ir = optimizer.optimize(ir)
302
303 bytecode, _ = compile_ir.assembly_to_evm(
304 compile_ir.compile_to_assembly(ir, optimize=optimize)
305 )
306
307 abi = kwargs.get("abi") or []
308 c = w3.eth.contract(abi=abi, bytecode=bytecode)
309 deploy_transaction = c.constructor()
310 tx_hash = deploy_transaction.transact()
311 address = w3.eth.get_transaction_receipt(tx_hash)["contractAddress"]
312 contract = w3.eth.contract(
313 address, abi=abi, bytecode=bytecode, ContractFactoryClass=VyperContract
314 )
315 return contract
316
317 return ir_compiler
318
319
320def _get_contract(
321 w3,
322 source_code,
323 optimize,
324 output_formats,
325 *args,
326 override_opt_level=None,
327 input_bundle=None,
328 **kwargs,
329):
330 settings = Settings()
331 settings.optimize = override_opt_level or optimize
332 out = compiler.compile_code(
333 source_code,
334 # test that all output formats can get generated
335 output_formats=output_formats,
336 settings=settings,
337 input_bundle=input_bundle,
338 show_gas_estimates=True, # Enable gas estimates for testing
339 )
340 parse_vyper_source(source_code) # Test grammar.
341 json.dumps(out["metadata"]) # test metadata is json serializable
342 abi = out["abi"]
343 bytecode = out["bytecode"]
344 value = kwargs.pop("value_in_eth", 0) * 10**18 # Handle deploying with an eth value.
345 c = w3.eth.contract(abi=abi, bytecode=bytecode)
346 deploy_transaction = c.constructor(*args)
347 tx_info = {"from": w3.eth.accounts[0], "value": value, "gasPrice": 0}
348 tx_info.update(kwargs)
349 tx_hash = deploy_transaction.transact(tx_info)
350 address = w3.eth.get_transaction_receipt(tx_hash)["contractAddress"]
351 return w3.eth.contract(address, abi=abi, bytecode=bytecode, ContractFactoryClass=VyperContract)
352
353
354@pytest.fixture(scope="module")
355def get_contract(w3, optimize, output_formats):
356 def fn(source_code, *args, **kwargs):
357 return _get_contract(w3, source_code, optimize, output_formats, *args, **kwargs)
358
359 return fn
360
361
362@pytest.fixture
363def get_contract_with_gas_estimation(tester, w3, optimize, output_formats):
364 def get_contract_with_gas_estimation(source_code, *args, **kwargs):
365 contract = _get_contract(w3, source_code, optimize, output_formats, *args, **kwargs)
366 for abi_ in contract._classic_contract.functions.abi:
367 if abi_["type"] == "function":
368 set_decorator_to_contract_function(w3, tester, contract, source_code, abi_["name"])
369 return contract
370
371 return get_contract_with_gas_estimation
372
373
374@pytest.fixture
375def get_contract_with_gas_estimation_for_constants(w3, optimize, output_formats):
376 def get_contract_with_gas_estimation_for_constants(source_code, *args, **kwargs):
377 return _get_contract(w3, source_code, optimize, output_formats, *args, **kwargs)
378
379 return get_contract_with_gas_estimation_for_constants
380
381
382@pytest.fixture(scope="module")
383def get_contract_module(optimize, output_formats):
384 """
385 This fixture is used for Hypothesis tests to ensure that
386 the same contract is called over multiple runs of the test.
387 """
388 custom_genesis = PyEVMBackend._generate_genesis_params(overrides={"gas_limit": 4500000})
389 custom_genesis["base_fee_per_gas"] = 0
390 backend = PyEVMBackend(genesis_parameters=custom_genesis)
391 tester = EthereumTester(backend=backend)
392 w3 = Web3(EthereumTesterProvider(tester))
393 w3.eth.set_gas_price_strategy(zero_gas_price_strategy)
394
395 def get_contract_module(source_code, *args, **kwargs):
396 return _get_contract(w3, source_code, optimize, output_formats, *args, **kwargs)
397
398 return get_contract_module
399
400
401def _deploy_blueprint_for(
402 w3, source_code, optimize, output_formats, initcode_prefix=ERC5202_PREFIX, **kwargs
403):
404 settings = Settings()
405 settings.optimize = optimize
406 out = compiler.compile_code(
407 source_code,
408 output_formats=output_formats,
409 settings=settings,
410 show_gas_estimates=True, # Enable gas estimates for testing
411 )
412 parse_vyper_source(source_code) # Test grammar.
413 abi = out["abi"]
414 bytecode = HexBytes(initcode_prefix) + HexBytes(out["bytecode"])
415 bytecode_len = len(bytecode)
416 bytecode_len_hex = hex(bytecode_len)[2:].rjust(4, "0")
417 # prepend a quick deploy preamble
418 deploy_preamble = HexBytes("61" + bytecode_len_hex + "3d81600a3d39f3")
419 deploy_bytecode = HexBytes(deploy_preamble) + bytecode
420
421 deployer_abi = [] # just a constructor
422 c = w3.eth.contract(abi=deployer_abi, bytecode=deploy_bytecode)
423 deploy_transaction = c.constructor()
424 tx_info = {"from": w3.eth.accounts[0], "value": 0, "gasPrice": 0}
425
426 tx_hash = deploy_transaction.transact(tx_info)
427 address = w3.eth.get_transaction_receipt(tx_hash)["contractAddress"]
428
429 # sanity check
430 assert w3.eth.get_code(address) == bytecode, (w3.eth.get_code(address), bytecode)
431
432 def factory(address):
433 return w3.eth.contract(
434 address, abi=abi, bytecode=bytecode, ContractFactoryClass=VyperContract
435 )
436
437 return w3.eth.contract(address, bytecode=deploy_bytecode), factory
438
439
440@pytest.fixture(scope="module")
441def deploy_blueprint_for(w3, optimize, output_formats):
442 def deploy_blueprint_for(source_code, *args, **kwargs):
443 return _deploy_blueprint_for(w3, source_code, optimize, output_formats, *args, **kwargs)
444
445 return deploy_blueprint_for
446
447
448# TODO: this should not be a fixture.
449# remove me and replace all uses with `with pytest.raises`.
450@pytest.fixture
451def assert_compile_failed():
452 def assert_compile_failed(function_to_test, exception=Exception):
453 with pytest.raises(exception):
454 function_to_test()
455
456 return assert_compile_failed
457
458
459@pytest.fixture
460def create2_address_of(keccak):
461 def _f(_addr, _salt, _initcode):
462 prefix = HexBytes("0xff")
463 addr = HexBytes(_addr)
464 salt = HexBytes(_salt)
465 initcode = HexBytes(_initcode)
466 return keccak(prefix + addr + salt + keccak(initcode))[12:]
467
468 return _f
469
470
471@pytest.fixture
472def side_effects_contract(get_contract):
473 def generate(ret_type):
474 """
475 Generates a Vyper contract with an external `foo()` function, which
476 returns the specified return value of the specified return type, for
477 testing side effects using the `assert_side_effects_invoked` fixture.
478 """
479 code = f"""
480counter: public(uint256)
481
482@external
483def foo(s: {ret_type}) -> {ret_type}:
484 self.counter += 1
485 return s
486 """
487 contract = get_contract(code)
488 return contract
489
490 return generate
491
492
493@pytest.fixture
494def assert_side_effects_invoked():
495 def assert_side_effects_invoked(side_effects_contract, side_effects_trigger, n=1):
496 start_value = side_effects_contract.counter()
497
498 side_effects_trigger()
499
500 end_value = side_effects_contract.counter()
501 assert end_value == start_value + n
502
503 return assert_side_effects_invoked
504
505
506@pytest.fixture
507def get_logs(w3):
508 def get_logs(tx_hash, c, event_name):
509 tx_receipt = w3.eth.get_transaction_receipt(tx_hash)
510 return c._classic_contract.events[event_name]().process_receipt(tx_receipt)
511
512 return get_logs
513
514
515@pytest.fixture(scope="module")
516def tx_failed(tester):
517 @contextmanager
518 def fn(exception=TransactionFailed, exc_text=None):
519 snapshot_id = tester.take_snapshot()
520 with pytest.raises(exception) as excinfo:
521 yield excinfo
522 tester.revert_to_snapshot(snapshot_id)
523 if exc_text:
524 # TODO test equality
525 assert exc_text in str(excinfo.value), (exc_text, excinfo.value)
526
527 return fn
The final two fixtures are optional and will be discussed later. The rest of this chapter assumes that you have this code set up in your conftest.py
file.
Alternatively, you can import the fixtures to conftest.py
or use pytest plugins.
Writing a Basic Test¶
Assume the following simple contract storage.vy
. It has a single integer variable and a function to set that value.
1#pragma version >0.3.10
2
3storedData: public(int128)
4
5@deploy
6def __init__(_x: int128):
7 self.storedData = _x
8
9@external
10def set(_x: int128):
11 self.storedData = _x
We create a test file test_storage.py
where we write our tests in pytest style.
1import pytest
2
3INITIAL_VALUE = 4
4
5
6@pytest.fixture
7def storage_contract(w3, get_contract):
8 with open("examples/storage/storage.vy") as f:
9 contract_code = f.read()
10 # Pass constructor variables directly to the contract
11 contract = get_contract(contract_code, INITIAL_VALUE)
12 return contract
13
14
15def test_initial_state(storage_contract):
16 # Check if the constructor of the contract is set up properly
17 assert storage_contract.storedData() == INITIAL_VALUE
18
19
20def test_set(w3, storage_contract):
21 k0 = w3.eth.accounts[0]
22
23 # Let k0 try to set the value to 10
24 storage_contract.set(10, transact={"from": k0})
25 assert storage_contract.storedData() == 10 # Directly access storedData
26
27 # Let k0 try to set the value to -5
28 storage_contract.set(-5, transact={"from": k0})
29 assert storage_contract.storedData() == -5
First we create a fixture for the contract which will compile our contract and set up a Web3 contract object. We then use this fixture for our test functions to interact with the contract.
Note
To run the tests, call pytest
or python -m pytest
from your project directory.
Events and Failed Transactions¶
To test events and failed transactions we expand our simple storage contract to include an event and two conditions for a failed transaction: advanced_storage.vy
1#pragma version >0.3.10
2
3event DataChange:
4 setter: indexed(address)
5 value: int128
6
7storedData: public(int128)
8
9@deploy
10def __init__(_x: int128):
11 self.storedData = _x
12
13@external
14def set(_x: int128):
15 assert _x >= 0, "No negative values"
16 assert self.storedData < 100, "Storage is locked when 100 or more is stored"
17 self.storedData = _x
18 log DataChange(msg.sender, _x)
19
20@external
21def reset():
22 self.storedData = 0
Next, we take a look at the two fixtures that will allow us to read the event logs and to check for failed transactions.
@pytest.fixture(scope="module")
def tx_failed(tester):
@contextmanager
def fn(exception=TransactionFailed, exc_text=None):
snapshot_id = tester.take_snapshot()
with pytest.raises(exception) as excinfo:
yield excinfo
tester.revert_to_snapshot(snapshot_id)
if exc_text:
# TODO test equality
assert exc_text in str(excinfo.value), (exc_text, excinfo.value)
return fn
The fixture to assert failed transactions defaults to check for a TransactionFailed
exception, but can be used to check for different exceptions too, as shown below. Also note that the chain gets reverted to the state before the failed transaction.
@pytest.fixture
def get_logs(w3):
def get_logs(tx_hash, c, event_name):
tx_receipt = w3.eth.get_transaction_receipt(tx_hash)
return c._classic_contract.events[event_name]().process_receipt(tx_receipt)
return get_logs
This fixture will return a tuple with all the logs for a certain event and transaction. The length of the tuple equals the number of events (of the specified type) logged and should be checked first.
Finally, we create a new file test_advanced_storage.py
where we use the new fixtures to test failed transactions and events.
1import pytest
2from web3.exceptions import ValidationError
3
4INITIAL_VALUE = 4
5
6
7@pytest.fixture
8def adv_storage_contract(w3, get_contract):
9 with open("examples/storage/advanced_storage.vy") as f:
10 contract_code = f.read()
11 # Pass constructor variables directly to the contract
12 contract = get_contract(contract_code, INITIAL_VALUE)
13 return contract
14
15
16def test_initial_state(adv_storage_contract):
17 # Check if the constructor of the contract is set up properly
18 assert adv_storage_contract.storedData() == INITIAL_VALUE
19
20
21def test_failed_transactions(w3, adv_storage_contract, tx_failed):
22 k1 = w3.eth.accounts[1]
23
24 # Try to set the storage to a negative amount
25 with tx_failed():
26 adv_storage_contract.set(-10, transact={"from": k1})
27
28 # Lock the contract by storing more than 100. Then try to change the value
29 adv_storage_contract.set(150, transact={"from": k1})
30 with tx_failed():
31 adv_storage_contract.set(10, transact={"from": k1})
32
33 # Reset the contract and try to change the value
34 adv_storage_contract.reset(transact={"from": k1})
35 adv_storage_contract.set(10, transact={"from": k1})
36 assert adv_storage_contract.storedData() == 10
37
38 # Assert a different exception (ValidationError for non-matching argument type)
39 with tx_failed(ValidationError):
40 adv_storage_contract.set("foo", transact={"from": k1})
41
42 # Assert a different exception that contains specific text
43 with tx_failed(ValidationError, "invocation failed due to improper number of arguments"):
44 adv_storage_contract.set(1, 2, transact={"from": k1})
45
46
47def test_events(w3, adv_storage_contract, get_logs):
48 k1, k2 = w3.eth.accounts[:2]
49
50 tx1 = adv_storage_contract.set(10, transact={"from": k1})
51 tx2 = adv_storage_contract.set(20, transact={"from": k2})
52 tx3 = adv_storage_contract.reset(transact={"from": k1})
53
54 # Save DataChange logs from all three transactions
55 logs1 = get_logs(tx1, adv_storage_contract, "DataChange")
56 logs2 = get_logs(tx2, adv_storage_contract, "DataChange")
57 logs3 = get_logs(tx3, adv_storage_contract, "DataChange")
58
59 # Check log contents
60 assert len(logs1) == 1
61 assert logs1[0].args.value == 10
62
63 assert len(logs2) == 1
64 assert logs2[0].args.setter == k2
65
66 assert not logs3 # tx3 does not generate a log