Question

我正在对费用模型上的方法进行单元测试。模型的相关部分如下所示：

class Expense(ndb.Model):

    user = ndb.KeyProperty(User, required=True)
    timestamp = ndb.DateTimeProperty(required=True)
    ...

    @staticmethod
    def new(user, amount, comment, description, timestamp):
        """creates a new expense and stores it. It returns the Expense instance"""
        ... validation ...
        exp = Expense(user=user, timestamp=timestamp, ...)
        exp.put()
        return exp

    @staticmethod
    def list(user, from_date=None, to_date=None):
        ...  
        query = Expense.query(Expense.user == user)
        if from_date is not None:
            if not isinstance(from_date, datetime.datetime):
                raise ValueError("from_date must be a datetime.datetime instance")
            query.filter(Expense.timestamp >= from_date)
        if to_date is not None:
            if not isinstance(to_date, datetime.datetime):
                raise ValueError("to_date must be a datetime.datetime instance")
            query.filter(Expense.timestamp <= to_date)
        query.order(- Expense.timestamp)
        return query

我有以下单元测试来测试Expense.list：

测试的前4行创建Expense模型实例的实例。

2013年1月3日一个
2013年11月1日一个
2013年11月2日一个
2014年1月1日一个

主页，为您节省一些水平滚动。

def test_list_expenses_filter_by_date(user):
    expense1 = Expense.new(user=user, amount=200.12, description="a netbook", comment="", timestamp=datetime.datetime(year=2013, month=1, day=3, hour=12, minute=30))
    expense2 = Expense.new(user=user, amount=1.0, description="A can of coke", comment="Really cheap!",timestamp=datetime.datetime(year=2013, month=11, day=1, hour=12, minute=30))
    expense3 = Expense.new(user=user, amount=3.05, description="A burger", comment="Tasty!", timestamp=datetime.datetime(year=2013, month=11, day=2, hour=12))
    expense4 = Expense.new(user=user, amount=0.30, description="Toilet visit", comment="I normally don't pay for these things, but it was urgent.", timestamp=datetime.datetime(year=2014, month=1, day=1, hour=1, minute=15))

    from_date = datetime.datetime(year=2013, month=5, day=1)
    to_date = datetime.datetime(year=2013, month=12, day=31)
    exps  = Expense.list(user=user, from_date=from_date, to_date=to_date)
    for expense in exps:
        assert from_date <= expense.timestamp <= to_date

但是当我从pytest运行这个测试时，我在下一行得到一个AssertionError，如pytest所示：

assert datetime.datetime(2013, 5, 1, 0, 0) <= datetime.datetime(2013, 1, 3, 12, 30)

E +，其中datetime.datetime（2013,1,3,12,30）=费用（key = Key（'Expense'，5066549580791808），金额= 200.12，评论= u''，desc ... tamp = datetime.datetime（2013,1,3,12,30），user = Key（'User'，5629499534213120））。timestamp

那么为什么我的Expense.list方法返回的实例的数据超出范围？

我已经在app引擎测试平台和请求处理程序中尝试了这一点，在浏览器中查看输出，因此它不是数据存储区存根中的错误。

我也尝试过不同的构建查询。我没有反复调用Query.filter，而是将过滤器表达式添加到列表中，将该列表作为*args传递给ndb.AND并将其传递给单个Query.filter，但这不起作用任

我已经排除了ndb中出现错误的可能性。以下测试通过：

def test_ndb_date():
    from google.appengine.ext import ndb

    class Time(ndb.Model):
        timestamp = ndb.DateTimeProperty(required=True)

    t1 = Time(timestamp=datetime.datetime.now() - datetime.timedelta(days=365))
    t2 = Time(timestamp=datetime.datetime.now())
    t3 = Time(timestamp=datetime.datetime.now() + datetime.timedelta(days=365))
    ndb.put_multi([t1, t2, t3])
    from_date = datetime.datetime.now() - datetime.timedelta(days=1)
    to_date = datetime.datetime.now() + datetime.timedelta(days = 1)
    result = Time.query(Time.timestamp <= from_date, Time.timestamp >= to_date).fetch()
    for time in result:
        assert from_date <= time.timestamp >= to_date

Answer 1

我误解了Query.filter是如何运作的。它不会更改当前的Query实例，但会返回一个新实例。

ndb没有正确查询日期

1 个答案: