From: rogeeff (rogeeff_at_[hidden])
Date: 2001-12-21 12:24:25
--- In boost_at_y..., "Fernando Cacciola" <fcacciola_at_g...> wrote:
> Gennady,
>
> I'm using the Unit Test Framework for testing my own code.
>
> I've found that you can add a test case being a class member
function:
>
> class A
> {
> void foo() ;
> } ;
> ...
> test->add( BOOST_TEST_CASE( &A::foo) );
>
> First, when I saw this sort of example in the documentation, I
figured that
> there was a mistake, and that
> foo() is a static method, because there isn't any instance of A
created (as
> shown by the example)
>
> Then I realize, that actually, the test case internally creates
a 'new'
> A::A() by itself.
>
> This should be properly documented.
From the documentation:
"The class_test_case is responsible for the creation and the
destroying of the user's test class instance. It's recommended to use
the class_test_case *only* if you can't implement a test logic in a
free function."
>
> Second: in my particular case, I NEED to test A::foo() but upon a
properly
> constructed A instance.
use free_function and do whatever you need. For example:
void test_A()
{
A a(...)
a.foo();
}
> It makes no sense at all to test A::foo() on a default constructed
A.
>
> That is, I need something like:
>
> class A
> {
> A ( ... ) ;
> void foo() ;
> } ;
>
> ...
> A a(....);
> test->add( BOOST_TEST_CASE( make_closure(a, &A::foo) ) );
First of all you will be hit by lifetime issues again. But what is
more important: I think free function implementation should suit for
you. Is it?
>
> Adding this functionality to unit_test_suite.hpp wouldn't be so
difficult,
> but I encountered a problem:
>
> What's the rational of test_case::init()/destroy().
>
> It *creates* and *destroys* test cases (in this cases 'A's) on
behalf of the
> user.
>
> In the example case above, if the test_suite() destroys 'a' and
then creates
> another 'A'by default, the 'foo' method being tested will behave
> unexpectedly.
>
> So, is the automatic init()/destroy() scheme really needed? What's
its
> purpose?
In reality usage of class_test_case is limited to the situations
where you for any reason need to share information between test
cases. The instance of user class is just a storage for this
information. As an example let say you are testing very heavy class
A. So you have test_construction test case and test_access test case.
You could want to use preconstructed object in a test_access and
construct it in test_construction.
There could be some other rare cases when you need class_test_case.
Another remark from doc:
"Due to usage of templates in an implementation of the
class_test_case, a compilation can be longer would you use the
function_test_case."
So use it *only* if you can't implement the same logic in a free
function.
>
> Is there any (other) way to test a method associated with a given
class
> *instance*?, or it can only test (conceptually static) class
methods.
>
> TIA,
>
> Fernando Cacciola
> Sierra s.r.l.
> fcacciola_at_g...
> www.gosierra.com
>
Gennadiy.