db.query(User).filter(User.id = id).first() always return None

[alexnguyen2201]

Describe the bug
It's fine if sfwafawfcwafawf but first:

db.query(User).filter(User.id = id).sfwafawfcwafawf()= 112

but first:

db.query(User).filter(User.id = id).first() = None

To Reproduce
For example:

    def test_find_user():
        db = UnifiedAlchemyMagicMock()
        db.query.return_value.filter.return_value.first.return_value = 112
        UserRepository(db).find_user(id=1)
        assert 0

and

    def find_user(id: int) -> None:
        print("result of mock db:", db.query(User).filter(User.id = id).first())

Expected behavior
If i set: db.query.return_value.filter.return_value.first.return_value = 112

So the result of db.query().filter().first() should be 112

Screenshots
If applicable, add screenshots to help explain your problem.

• OS: MacOS Monterey
• Version 12.3.1

[facundopadilla]

I have the same problem!
OS: Kubuntu 22.04
Version: mock-alchemy==0.2.5

[facundopadilla]

I think I found the error but I am not sure if it is this one:

• mock_alchemy/mocking.py in line 620:

for calls, result in sorted_mock_data:
    calls = [
        sqlalchemy_call(
            i,
            with_name=True,
            base_call=self.unify.get(i[0]) or Call,
        )
        for i in calls
    ]
    if all(c in previous_calls for c in calls):  # line 620
        return self.boundary[_mock_name](result, *args, **kwargs)

This check if the some call exists in previous_calls (created in line 590)

For example, in my case I have this:

• Calls: [call.query(User), call.filter(User.username == "test"), call.first()]
• Return value: [User(id=1, username="test", password="test")]

Code:

session = UnifiedAlchemyMock(
    data=[([call.query(User), call.filter(User.username == "test"), call.first()], [User(id=1, username="test", password="test")])]
)

When line 620 is to be executed, the previous_calls has this:

[
    call.filter(BinaryExpression(sql='users.username = :username_1', params={'username_1': 'test'})),
    call.query(<class 'project.models.users.User'>), 
    call.__len__(),
    call.__str__(),
    call.__len__()
]

The call first() is not added in previous_calls, then it fails.

I guess it must be because the first() is not a method of sqlalchemy as such, i.e. as a query, but it is a method of the same object that returns the filter and returns the first of the list as if it were a slicing (any_list[0])

# sqlalchemy/orm/query.py - line 2799
def first(self):
    if self._statement is not None:
        return self._iter().first()
    else:
        return self.limit(1)._iter().first()