example_test.py

from fixture import TestCase
from google.appengine.ext import ndb
from hypothesis import given
from hypothesis.strategies import (floats, integers, text, booleans,
                                   datetimes, none, fixed_dictionaries,
                                   lists, sampled_from, composite)
from user import User


PROPERTIES = {
    ndb.model.IntegerProperty: lambda: integers(),
    ndb.model.FloatProperty: lambda: floats(allow_nan=False, allow_infinity=False),
    ndb.model.BooleanProperty: lambda: booleans(),
    ndb.model.StringProperty: lambda: text(max_size=500),
    ndb.model.TextProperty: lambda: text(),
    ndb.model.DateTimeProperty: lambda: datetimes(),
    ndb.model.StructuredProperty: lambda: none()
}


def property_strategy(prop):
    strategy_fx = PROPERTIES[type(prop)]
    strategy = strategy_fx()
    if prop._repeated:
        strategy = lists(strategy)
    if prop._choices:
        ls = list(prop._choices)
        return sampled_from(ls)
    return strategy


def properties_strategy(klass):
    assert type(klass) == ndb.model.MetaModel
    props = klass._properties

    gens = {k:property_strategy(v) for k,v in props.items()
            if type(v) is not ndb.model.ComputedProperty}

    return fixed_dictionaries(gens)


@composite
def entity_strategy(draw, klass):
    prop_dict = draw(properties_strategy(klass))
    return klass(**prop_dict)


class UserTest(TestCase):
  
    @given(entity_strategy(User))
    def test_user(self, user):
        assert user