Cacher is the code snippet organizer for pro developers

# tests/test_user_model.py
# ...
class BasicTestCase(unittest.TestCase):
    # ...
    def test_email_change(self):
        u = User(email='john@example.com', username='john', password='cat')
        db.session.add(u)
        db.session.commit()

        token = u.generate_email_change_token('john@example.com')
        self.assertFalse(u.email_change(token))

        token = u.generate_email_change_token('mary@example.com')
        self.assertTrue(u.email_change(token))
        self.assertEqual(u.email, 'mary@example.com')
        self.assertNotEqual(u.email, 'john@example.com')

        token = u.generate_email_change_token(None)
        self.assertFalse(u.email_change(token))

        token = u.generate_email_change_token('john@example.com')
        db.session.delete(u)
        db.session.commit()
        self.assertFalse(u.email_change(token))