def test_laziness():
def crash_after_first_val():
yield 1
raise Exception("oops, iterated past first value")
repeated_use = CachedIterable(crash_after_first_val())
assert first(repeated_use) == 1
assert first(repeated_use) == 1
def __init__(self, coinbase: Address, timestamp: int, block_number: int,
difficulty: int, gas_limit: int,
prev_hashes: Iterable[Hash32]) -> None:
self._coinbase = coinbase
self._timestamp = timestamp
self._block_number = block_number
self._difficulty = difficulty
self._gas_limit = gas_limit
self._prev_hashes = CachedIterable(prev_hashes)
def __init__(self,
coinbase: Address,
timestamp: int,
block_number: BlockNumber,
difficulty: int,
gas_limit: int,
prev_hashes: Iterable[Hash32],
chain_id: int,
base_fee_per_gas: Optional[int] = None) -> None:
self._coinbase = coinbase
self._timestamp = timestamp
self._block_number = block_number
self._difficulty = difficulty
self._gas_limit = gas_limit
self._prev_hashes = CachedIterable(prev_hashes)
self._chain_id = chain_id
self._base_fee_per_gas = base_fee_per_gas
def test_cached_generator():
use_once = itertools.count()
repeated_use = CachedIterable(use_once)
for find_val in [1, 0, 10, 5]:
assert find_val == nth(find_val, repeated_use)
def test_cached_generator_iterable():
input_vals = [2]
repeated_use = CachedIterable(input_vals)
assert list(repeated_use) == input_vals
assert list(repeated_use) == input_vals