Computing test methods in unittest.TestCase

[Jan Decaluwe]

James Kew wrote:
> "Jan Decaluwe" <jan at jandecaluwe.com> wrote in message
> news:4044BE1E.7000408 at jandecaluwe.com...
> 
>>>class FSMTest(unittest.TestCase):
>>
>>    ....
>>    for st, trs in transitionTable.items():
>>        for i, tr in enumerate(trs):
>>            def _tmpfunc(self, st=st, tr=tr):
>>                sim = Simulation(self.bench(st, tr))
>>                sim.run()
>>            _tmpfunc.func_doc = "Check state %s - %s" % (st, getDoc(tr))
>>            exec "test_%s_%s = _tmpfunc" % (st, i)
>>
>>This works, but uses some "ugly" tricks:
>>
>>* default arguments to pass context info. As the code is executed in
>>  class context, not function context, I cannot use free variables.
>>* The use of 'exec'. unittest looks for methods with name prefix
>>  'test_' in the class namespace, and I didn't find another way
>>  to achieve that.
>>
>>Anyone with better ideas?
> 
> 
> Define the test methods after defining the class, and inject them into the
> class with setattr:
> 
> class testClass:
>     pass
> 
> def makeTest(param):
>     def test(self):
>         print "test: param=%s" % param
>     return test
> 
> setattr(testClass, "test1", makeTest(1))
> setattr(testClass, "testHello", makeTest("Hello"))

Thanks - this is a nice way to get rid of the exec. However, I found
out that I still need the default arguments in my case. Free variables
do behave differently as shown in the following example:

def funcs():
    flist = []
    glist = []
    for i in range(3):
        def f():
            print "f: " + str(i)
        def g(i=i):
            print "g: " + str(i)
        flist.append(f)
        glist.append(g)
    for f, g in zip(flist, glist):
        f(); g()

>>> funcs()
f: 2
g: 0
f: 2
g: 1
f: 2
g: 2

When generating such functions (with free variables) in loops,
it's apparently very easy to get it wrong ...

Regards, Jan

-- 
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