unittest assertRaises Problem

[john]

All:

Hi. I am an experienced developer (15 yrs), but new to Python and have
a question re unittest and assertRaises. No matter what I raise,
assertRaises is never successful. Here is the test code:
class Foo:
def testException(self):
raise ValueError

class FooTestCase(unittest.TestCase):

testTryThis(self):
f = Foo()
self.assertRaises(ValueError, f.testException())

This fails --- unittest reports the following:
FAILED (errors=1)

This seems like the most basic thing in the world. I am running Python
2.5 on Windows XP using Eclipse and PyDev

Any help appreciated.

Thanks,
John

[attn.steven.kuo]

On Apr 16, 3:13 pm, "john" <[e-mail]:

All:

Hi. I am an experienced developer (15 yrs), but new to Python and have
a question re unittest and assertRaises. No matter what I raise,
assertRaises is never successful. Here is the test code:

class Foo:
def testException(self):
raise ValueError

class FooTestCase(unittest.TestCase):

testTryThis(self):
f = Foo()
self.assertRaises(ValueError, f.testException())

The second argument should be a callable object, not the
result from invoking that callable object. Thus, change

self.assertRaises(ValueError, f.testException())

to

self.assertRaises(ValueError, f.testException)

--
Hope this helps,
Steven

[john]

On Apr 16, 6:35 pm, Jean-Paul Calderone <[e-mail]:

On 16 Apr 2007 15:13:42 -0700, john <[e-mail]:

All:

Hi. I am an experienced developer (15 yrs), but new to Python and have
a question re unittest and assertRaises. No matter what I raise,
assertRaises is never successful. Here is the test code:

class Foo:
def testException(self):
raise ValueError

class FooTestCase(unittest.TestCase):

testTryThis(self):
f = Foo()
self.assertRaises(ValueError, f.testException())

The 2nd argument to assertRaises should be a callable. assertRaises
will call it (so that it can do exception handling), so you shouldn't:

self.assertRaises(ValueError, f.testException)

Jean-Paul

Steven, Jean-Paul:

Thank you both for your answers - worked like a charm!

Best,
John