hypothesize_comparisons.py

import unittest

from hypothesis import given, strategies as st


class ComparisonTests(unittest.TestCase):

    def assertNonesCauseTypeError(self, first, second):
        try:
            first > second
        except TypeError:
            comparison_raised = True
        else:
            comparison_raised = False

        try:
            for i in range(min(len(first), len(second))):
                if first[i] > second[i] or first[i] < second[i]:
                    break
        except TypeError:
            iteration_raised = True
        else:
            iteration_raised = False

        self.assertEqual(comparison_raised, iteration_raised,
                         "comparison_raised={!r} "
                         "iteration_raised={!r} "
                         "{!r} {!r}".format(comparison_raised,
                                            iteration_raised,
                                            first, second))

    @given(
        first=st.lists(st.just(None) | st.integers()).map(tuple),
        second=st.lists(st.just(None) | st.integers()).map(tuple),
    )
    def test_tuple_comparison(self, first, second):
        self.assertNonesCauseTypeError(first, second)

    @given(
        first=st.lists(st.just(None) | st.integers()),
        second=st.lists(st.just(None) | st.integers()),
    )
    def test_list_comparison(self, first, second):
        self.assertNonesCauseTypeError(first, second)