Question

My custom exception classes:

class MyCustomException(Exception):
    pass

class MyCustomRestException(MyCustomException):

    def __init__(self, status, uri, msg=""):
        self.uri = uri
        self.status = status
        self.msg = msg
        super(MyCustomException, self).__init__(msg)

    def __str__(self):
        return "HTTP ERROR %s: %s \n %s" % (self.status, self.msg, self.uri)

My Test

# note: @raises(MyCustomRestException) works by itself
@raises(MyCustomRestException, 'HTTP ERROR 403: Invalid User')
def test_bad_token():
    sc = SomeClass('xxx', account_number)
    result = ec.method_that_generates_exception()

Here’s what nose spits back out

12:52:13 ~/sandbox/ec$ nosetests -v
Failure: AttributeError ('str' object has no attribute '__name__') ... ERROR

======================================================================
ERROR: Failure: AttributeError ('str' object has no attribute '__name__')
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/nose/loader.py", line 390, in loadTestsFromName
    addr.filename, addr.module)
  File "/usr/local/lib/python2.7/site-packages/nose/importer.py", line 39, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/usr/local/lib/python2.7/site-packages/nose/importer.py", line 86, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/ec/tests/my_client_tests.py", line 16, in <module>
    @raises(MyCustomRestException, 'HTTP ERROR 403: Invalid User')
  File "/usr/local/lib/python2.7/site-packages/nose/tools/nontrivial.py", line 55, in raises
    valid = ' or '.join([e.__name__ for e in exceptions])
AttributeError: 'str' object has no attribute '__name__'

----------------------------------------------------------------------
Ran 1 test in 0.012s

FAILED (errors=1)

So …

My questions is two fold:

• How do I fix this error?
• How can I test (individually or altogether):
  • Exception Type
  • Exception.status
  • Exception.uri
  • Exception.msg

Solution: with help from alynna (below)

This works great.

def test_bad_token():
    sc = SomeClass('xxx', account_number)

    with assert_raises(MyCustomRestException) as e:
        sc.method_that_generates_exception()

    assert_equal(e.exception.status, 403)
    assert_equal(e.exception.msg, 'Invalid User')

Answer 1

I think your problem is that the arguments to the @raises decorator are expected to all be exception classes: https://nose.readthedocs.org/en/latest/testing_tools.html#nose.tools.raises

You might want assertRaises instead. The documentation shows it being used to test extra attributes of exceptions: http://docs.python.org/2/library/unittest.html#unittest.TestCase.assertRaises