Asserting exact exception instances

mauve · March 12, 2025, 9:21am

Here’s a different answer - somebody did write it in the CPython repo (jeffrey.yasskin in r59974 in 2008):

Lib/test/test_fractions.py

155c44b90


      
          def assertRaisesMessage(self, exc_type, message,
                                  callable, *args, **kwargs):
              """Asserts that callable(*args, **kwargs) raises exc_type(message)."""
              try:
                  callable(*args, **kwargs)
              except exc_type as e:
                  self.assertEqual(message, str(e))
              else:
                  self.fail("%s not raised" % exc_type.__name__)

It’s also in Django: