What is the proper way of testing simple CRUD operations with Pytest to ensure correct reads and writes? Function object instead of value is returned - pytest

Question

Using Pytest, I am trying to test a simple database read function and an update function.
The update function needs to be run first to ensure the test database has the values we will test for in our read function.
In /src there is my main script, here are the read, update, delete functions:
async def read(self, collection, query=None, mods=None):
Table = self._cache.classes[collection]
async with self._session() as session:
matches = set(Table.__mapper__.columns.keys()) & set(mods['fields'])
for m in matches:
q = select(getattr(Table, m))
q = q.filter_by(**query)
result = await session.execute(q)
return [row for row in result]
async def update(self, collection, query, data):
Table = self._cache.classes[collection]
async with self._session() as s:
q = sa_update(Table).filter_by(**query)
q = q.values(**data)
await s.execute(q)
await s.commit()
async def delete_collection(self, table_name, syncro_engine=sync_engine):
table = self.retrieve_table_obj(table_name)
async with self._engine.begin() as conn:
await conn.run_sync(Base.metadata.drop_all(syncro_engine, [table], checkfirst=True))
When running read the output is [('Wonderland',)] so this is what I am testing in assert in Pytest.
In /test I have a conftest.py file that has these three functions:
#pytest.fixture(scope='function')
def test_update():
def get_update(collection, query, data):
return asyncio.run(DB.update(collection, query, data))
return get_update
#pytest.fixture(scope='function')
def test_read():
def get_read(collection, query, mods):
return asyncio.run(DB.read(collection, query, mods))
return get_read
#pytest.fixture(scope='function')
def drop_table():
def get_delete_tables(table_name, sync_engine):
return asyncio.run(DB.delete_collection(table_name, sync_engine))
return get_delete_tables
Then the tests get run in test_db.py:
# Tests 'update' by updating user 'Alice' with 'org' 'Wonderland'
# Doesn't return anything, using it to ensure the correct values are in test_db to test the read function
#pytest.mark.parametrize('function_input, expected',
[("'user', {'name': 'Alice'}, {'org': 'Wonderland'})", "[('Wonderland',)]")])
def test_update(test_update, function_input, expected):
test_update
# Tests 'read' by reading the just-updated values
#pytest.mark.parametrize('function_input, expected',
[("'user', query={'name': 'Alice'}, mods={'fields': ['name', 'org']})", "[('Wonderland',)]")])
def test_read(test_read, function_input, expected):
assert test_read == expected
# Tests that tables are dropped cleanly by dropping a given table then checking for that table name
#pytest.mark.parametrize('fn_input1, fn_input2, expected',
[('image', sync_engine, 'image')])
def test_drop_table(drop_table, collection_names, fn_input1, fn_input2, expected):
# First drop the table
drop_table(fn_input1, fn_input2)
# Now check that it no longer exists
with pytest.raises(KeyError) as error_info:
assert fn_input1 in collection_names
raise KeyError
assert error_info.type is KeyError
Running test_drop_table does not drop anything from test_db even though it's being passed the correct database test_db and its counterpart in the main script in /src works properly.
When I run this test_read test it fails:
> assert test_read == expected
E assert <function test_read.<locals>.get_read at 0x7f1fa6beed08> == "[('Wonderland',)]"
How can I access the actual returned value to assert against, i.e. [('Wonderland',)], rather than the <function object>?