assert introspection despite of custom message

[pmeier]

The documentation states

However, if you specify a message with the assertion like this:

assert a % 2 == 0, "value was odd, should be even"

then no assertion introspection takes places at all and the message will be simply shown in the traceback.

Running

def foo():
    return 1


def test_foo():
     assert foo() % 2 == 0, "value was odd, should be even"

gives the following output

________________________________________________ test_foo _________________________________________________

    def test_foo():
>        assert foo() % 2 == 0, "value was odd, should be even"
E        AssertionError: value was odd, should be even
E        assert (1 % 2) == 0
E         +  where 1 = foo()

Given that there is introspection, I'm either misinterpreting the documentation or it is wrong / outdated. Could someone tell me which one is the case?

Bonus: Can someone tell me how to disable this introspection locally instead going for the whole module or test suite?

[RonnyPfannschmidt]

i believe --assert=plain should do the trick of disable

wrt the docs, at first glance i believe its misleading there,
my understanding is that assertrepr_compare is disabled but not all inspection

i'll have to crosscheck later when i find some more time, for clarity we should include a example output that makes sense in any case

[RonnyPfannschmidt]

whops, i did misread a bit, currently you have to go for the whole testsuite

[pmeier]

While it is not helpful in my case, you can disable introspection on a module level:

Disable rewriting for a specific module by adding the string PYTEST_DONT_REWRITE to its docstring.