def test_roundrobin_failure_lengthhint3():
# Check if by adding the different lengths it could lead to overflow.
# We use two iterables both with sys.maxsize length.
it1 = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize)
it2 = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize)
it = roundrobin(it1, it2)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_grouper_lengthhint_failure2():
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
it = grouper(of_it, 2)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_accumulate_lengthhint_failure2():
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
acc = accumulate(of_it)
with pytest.raises(OverflowError):
operator.length_hint(acc)
with pytest.raises(OverflowError):
list(acc)
def test_sideeffects_failure_lengthhint2():
# This only checks for overflow if the length_hint is above PY_SSIZE_T_MAX
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
it = sideeffects(of_it, return_None)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_roundrobin_failure_lengthhint2():
# This only checks for overflow if the length_hint is above PY_SSIZE_T_MAX
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
it = roundrobin(of_it)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_intersperse_lengthhint_failure2():
# This is the easy way to overflow the length_hint: If the iterable itself
# has a length_hint > sys.maxsize
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
it = intersperse(of_it, 2)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_merge_lengthhint_failure5():
# Like the test above but this time with a "started" merge
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize)
it = merge(toT([1, 2, 3]), of_it)
next(it)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_intersperse_lengthhint_failure3():
# The length_hint method multiplies the length_hint of the iterable with
# 2 (and adds/subtracts 1) so it's actually possible to have overflow even
# if the length of the iterable doesn't trigger the overflow!
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize)
it = intersperse(of_it, 2)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_merge_lengthhint_failure4():
# Overflow could also happen when adding length_hints that individually are
# below the sys.maxsize
# In this case we have 3 + sys.maxsize
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize)
it = merge(toT([1, 2, 3]), of_it)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_replicate_failure_lengthhint3():
# It is also possible that the length_hint overflows when the length is
# below maxsize but "times * length" is above maxsize.
# In this case length = maxsize / 2 but times = 3
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize // 2)
it = replicate(of_it, 3)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_successive_failure_lengthhint2():
# This only checks for overflow if the length_hint is above PY_SSIZE_T_MAX.
# In theory that would be possible because with times the length would be
# shorter but "length_hint" throws the exception so we propagate it.
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
it = successive(of_it)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_merge_lengthhint_failure3():
# Like the test case above but this time we take one item because
# internally an unstarted "merge" and started "merge" are treated
# differently
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize + 1)
it = merge(of_it)
next(it)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
def test_replicate_failure_lengthhint4():
# There is also the possibility that "length * times" does not overflow
# but adding the "times - timescurrent" afterwards will overflow.
# That's a bit tricky, but it seems that ((2**x-1) // 10) * 10 + 9 > 2**x-1
# is true for x=15, 31, 63 and 127 so it's possible by setting the times to
# 10 and the length to sys.maxsize // 10. The 9 are because the first item
# is already popped and should be replicated 9 more times.
of_it = _hf.OverflowLengthHint(toT([1, 2, 3]), sys.maxsize // 10)
it = replicate(of_it, 10)
next(it)
with pytest.raises(OverflowError):
operator.length_hint(it)
with pytest.raises(OverflowError):
list(it)
