Re: [Boost-build] [bbv2 test] explicit test-suite ?

From: David Abrahams (dave_at_[hidden])
Date: 2006-09-28 18:37:28

"Eric Niebler" <eric_at_[hidden]> writes:

> Rene Rivera wrote:
>> Eric Niebler wrote:
>>> I'm writing a Jamfile.v2 for some tests. I have two test suites, like:
>>>
>>>    import testing ;
>>>
>>>    {
>>>        test-suite blah : [ run stuff.cpp ] ;
>>>    }
>>>
>>>    {
>>>        test-suite blah-ext : [ run experimental.cpp ] ;
>>>    }
>>>
>>> Now, I'd like only the blah test suite to run by default, and I want 
>>> blah-ext to run only if I explicitly request it. The BBv2 docs led me to 
>>> believe "explicit" would help me, and I believed it! Sadly, it seems not 
>>> to be the case. Regardless of where I put the "explicit blah-ext ;" 
>>> line, the blah-ext test suite always runs, whether I ask for it or not.
>>>
>>> What have I overlooked?
>> 
>> Looking up the testing.jam code... "test-suite" isn't a target. 

Rene means to say that the first argument to the test-suite rule
doesn't become the name of a target.

> So, test-suite is not a target, and explicit only works on targets. 
> Fine. But what makes test-suite not a target? How can I tell based on 
> the syntax of:
>
>     test-suite blah : [ blarg.cpp ] ;
>
> that test-suite is not a target? Syntactically, it looks a lot like 
> things which are targets, right? 

No, that looks like a rule invocation (a.k.a. function call).  Whether
a rule invocation creates a target or not, and what that target is
called, is totally up to the implementation of the rule.

> Why are they (targets, aliases for targets) syntactically identical
> if they don't behave alike?
>
> Again, sorry if that's a stupid question.

Not stupid at all; systems like make would lead you to believe that
was a target declaration.  bjam doesn't syntactically distinguish
target declaration from other activities.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com