def test_empty_AND():
assert AND() is None
assert AND(True) is True
# sqlrepr() is needed because AND() returns an SQLExpression that overrides
# comparison. The following
# AND('x', 'y') == "foo bar"
# is True! (-: Eeek!
assert sqlrepr(AND(1, 2)) == sqlrepr(SQLOp("AND", 1, 2)) == "((1) AND (2))"
assert sqlrepr(AND(1, 2, '3'), "sqlite") == \
sqlrepr(SQLOp("AND", 1, SQLOp("AND", 2, '3')), "sqlite") == \
"((1) AND ((2) AND ('3')))"
def test_op():
instance = SQLOp('and', 'this', 'that')
assert sqlrepr(instance, 'mysql') == "(('this') AND ('that'))"