def test_iterator_step(self):
#iteration in C order with #contiguous layout => strides[-1] is 1
#skip less than the shape
shape = [3, 5]
strides = [5, 1]
backstrides = [x * (y - 1) for x,y in zip(strides, shape)]
assert backstrides == [10, 4]
i = ArrayIter(MockArray, support.product(shape), shape,
strides, backstrides)
s = i.reset()
s = i.next_skip_x(s, 2)
s = i.next_skip_x(s, 2)
s = i.next_skip_x(s, 2)
assert s.offset == 6
assert not i.done(s)
assert s.indices == [1,1]
#And for some big skips
s = i.next_skip_x(s, 5)
assert s.offset == 11
assert s.indices == [2,1]
s = i.next_skip_x(s, 5)
# Note: the offset does not overflow but recycles,
# this is good for broadcast
assert s.offset == 1
assert s.indices == [0,1]
assert i.done(s)
#Now what happens if the array is transposed? strides[-1] != 1
# therefore layout is non-contiguous
strides = [1, 3]
backstrides = [x * (y - 1) for x,y in zip(strides, shape)]
assert backstrides == [2, 12]
i = ArrayIter(MockArray, support.product(shape), shape,
strides, backstrides)
s = i.reset()
s = i.next_skip_x(s, 2)
s = i.next_skip_x(s, 2)
s = i.next_skip_x(s, 2)
assert s.offset == 4
assert s.indices == [1,1]
assert not i.done(s)
s = i.next_skip_x(s, 5)
assert s.offset == 5
assert s.indices == [2,1]
assert not i.done(s)
s = i.next_skip_x(s, 5)
assert s.indices == [0,1]
assert s.offset == 3
assert i.done(s)
