def test_schema_tofile():
from StringIO import StringIO
s = Schema()
n1 = Node()
n2 = Node()
s.add_node(n1)
s.add_node(n2)
s.connect_nodes(n1, n2)
f = StringIO()
s.to_disk(f)
f.seek(0)
s2 = Schema()
s2.from_disk(f)
assert(len(s.connections) == len(s2.connections))
assert(len(s.nodes) == len(s2.nodes))
def test_schema_connections():
schema = Schema()
n1 = Node()
n2 = Node()
n3 = Node()
schema.add_node(n1)
schema.add_node(n2)
assert_raises(ValueError, schema.connect_nodes, n1, n1)
schema.connect_nodes(n1, n2)
assert((n1, n2) in schema.connections)
assert(n1.out_conn[0] is n2)
assert(n2.in_conn[0] is n1)
assert_raises(ValueError, schema.disconnect_nodes, n2, n1)
schema.connect_nodes(n3, n2)
schema.disconnect_nodes(n1, n2)
assert(schema.connections == [(n3, n2)])
assert(n1.out_conn == [])
assert(n2.in_conn == [n3])
