Python unittest data provider

Question

I am trying to create a unit test in python that has a data provider. As the unittest library does not support this nativity, I'm using the unittest_data_provider package. I'm getting an error, and am not sure where it is coming from (I'm new to python).

My code

import unittest
from wikibase.dataModel.item_id import ItemId
from unittest_data_provider import data_provider


class TestItemId(unittest.TestCase):
    itemIds = lambda: (
        ( 'q42' ),
        ( 'Q42' ),
        ( 'Q1' ),
        ( 'Q1000' ),
        ( 'Q31337' ),
    )

    @data_provider(itemIds)
    def test_constructor(self, itemString):
        itemId = ItemId(itemString)
        self.assertEqual(itemId.getSerialization(), itemString)

The error I get:

File "/usr/local/lib/python3.3/dist-packages/unittest_data_provider/init.py", line 7, in repl fn(self, *i) TypeError: test_constructor() takes 2 positional arguments but 4 were given

This is using python 3.3.

Answer 1

Your itemIds function should return a tuple of tuples, but the way you have coded it, it is returning a tuple of strings. You need to add a , inside the parenthesis to return a single item tuple, try replacing your code with the following:

itemIds = lambda: (('q42',), ('Q42',), ('Q1', ), ('Q1000',), ('Q31337',),)