is it possible to show the assertion values that failed? It shows the traceback and what kind of exception was throw but it would more practical to know which values failed.
Example:
assert result.file == file
AssertionError
3 Answers
You should run nosetests -d this will display the values of the objects that fail the compare in assert.
1 Comment
badbishop
Nope, it is still "<bla.bla.bla object at 0x1068ad5a0>.uidNumber == 1001" instead of something like "expected 1001, got 1002"
assert result.file == file, "%s != %s" % (result.file, file,)
That's why ugly self.assert<Foo> methods were introduced in unittest.TestCase instead of nice and short asserts: self.assert<Foo> methods know how to display failure messages.
By the way, I thought that nose do some black magic so in simple cases
assert a == b
should show meaningful error message.
3 Comments
Pickels
Thanks, I should be using self.assert. You can let Nose show more info with -d. It will show the type but not the actual value.
Pickels
Just noticed why you said they were ugly. Parentheses and no ==...yuck.
Another possibility: define your own function that does the trick:
def assert_eq(obt, exp):
assert obt==exp, "\n*Expected:\n%s\n*Obtained:\n%s" % (exp, obt)
You can call it instead of assert:
assert_eq ( self.data['SQ'].code, "SQ" )
And this returns this nice error:
4 Comments
badbishop
Super! I wonder, if you add a third parameter - test description, that is - you don't even need to define a separate method for each simple test, do you? Basically, it'll look like equivalent of Perl's ok() method from Test::More.
Jean-Francois T.
@badbishop The method I described could work for all the tests. But yes, it could be customized by adding a third parameter with the message (could be optional with the default message being the one I described).
Robert Moskal
Always shocked by the amount of stuff that is left undone in python
Jean-Francois T.
@RobertMoskal Python is not assuming any behavior for you (like Perl would do like for example when doing
"123" + 4 and get 127 as a result :)
pytestis doing that out of the box (with small comparisons of strings, lists, and dictionaries).