def test_build_expr():
"""Test building an expression from a query dictionary"""
name_eq = expr.Comparison('name', expr.Eq('frank'))
assert expr.build_expr(name_eq) is name_eq
assert isinstance(expr.build_expr({}), expr.Empty)
assert isinstance(expr.build_expr({'name': 'tom', 'age': 54}), expr.And)
def test_expr_and_or():
"""Test expression and/or methods"""
name_eq = expr.Comparison('name', expr.Eq('frank'))
age_gt = expr.Comparison('age', expr.Gt(38))
anded = name_eq & age_gt
assert anded.dict() == {'$and': [name_eq.dict(), age_gt.dict()]}
ored = name_eq | age_gt
assert ored.dict() == {'$or': [name_eq.dict(), age_gt.dict()]}
with pytest.raises(TypeError):
name_eq & 'hello'
with pytest.raises(TypeError):
name_eq | 'goodbye'
# Test fusing
assert (anded & anded).operand == [name_eq, age_gt, name_eq, age_gt]
assert (anded | anded).operand != [name_eq, age_gt, name_eq, age_gt]
assert (ored | ored).operand == [name_eq, age_gt, name_eq, age_gt]
assert (ored & ored).operand != [name_eq, age_gt, name_eq, age_gt]
def test_expr_types_and_filters():
"""Test the query filters for expressions"""
name_eq = expr.Comparison('name', expr.Eq('frank'))
age_gt = expr.Comparison('age', expr.Gt(38))
# Check all operators
for expression in expr.SimpleOperator.__subclasses__():
assert expression.oper.startswith('$')
assert expression(True).dict() == {expression.oper: True}
# Check all logicals
for list_expr in expr.Logical.__subclasses__():
assert list_expr.oper.startswith('$')
if issubclass(list_expr, expr.WithListOperand):
assert list_expr([name_eq, age_gt]).dict() == \
{list_expr.oper: [name_eq.dict(), age_gt.dict()]}
# Check that the the passthrough for list expressions work
assert list_expr([name_eq]).dict() == name_eq.dict()
with pytest.raises(TypeError):
list_expr('non list')
with pytest.raises(TypeError):
list_expr(['non expression'])
else:
assert list_expr(name_eq).dict() == {
list_expr.oper: name_eq.dict()
}
with pytest.raises(TypeError):
list_expr(['non expression'])
assert expr.Empty().dict() == {}
with pytest.raises(TypeError):
# Comparison takes an operator, not a string
expr.Comparison('my_field', 'oper')