summaryrefslogtreecommitdiff
path: root/Lib/test/test_pep479.py
blob: bc235ceb00e3c9c0b6add1a4b526409cbb5c3db2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
from __future__ import generator_stop

import unittest


class TestPEP479(unittest.TestCase):
    def test_stopiteration_wrapping(self):
        def f():
            raise StopIteration
        def g():
            yield f()
        with self.assertRaisesRegex(RuntimeError,
                                    "generator raised StopIteration"):
            next(g())

    def test_stopiteration_wrapping_context(self):
        def f():
            raise StopIteration
        def g():
            yield f()

        try:
            next(g())
        except RuntimeError as exc:
            self.assertIs(type(exc.__cause__), StopIteration)
            self.assertIs(type(exc.__context__), StopIteration)
            self.assertTrue(exc.__suppress_context__)
        else:
            self.fail('__cause__, __context__, or __suppress_context__ '
                      'were not properly set')


if __name__ == '__main__':
    unittest.main()