Array being iterated over can be modified in another function

[smarx]

Modifying the array directly in the loop body is disallowed, so this could be considered a bug:

x: uint256[1]

@private
def store_in_x(index: uint256, value: uint256):
    self.x[index] = value

@public
def foo():
    for n in self.x:
        # self.x[0] = n * 2 # blocked with "Altering list 'self.x' which is being iterated!"
        self.store_in_x(0, n * 2) # BUG: allowed

[iamdefinitelyahuman]

Fixed in #2028