'When merging group_access on a block, if the intersection of group IDs
for a partition is empty, the merged value for that partition is False.'

@ddt.data(*PARENT_CHILD_PAIRS)
@ddt.unpack
def test_disjoint_groups(self, parent, child):

    parent_block = getattr(self, parent)
    child_block = getattr(self, child)
    self.set_group_access(parent_block, {self.PARTITION_1: [self.PARTITION_1_GROUP_1]})
    self.set_group_access(child_block, {self.PARTITION_1: [self.PARTITION_1_GROUP_2]})
    self.verify_group_access(parent_block, {self.PARTITION_1: [self.PARTITION_1_GROUP_1]})
    self.verify_group_access(child_block, {self.PARTITION_1: False})
