pyunit: remove a test case on the fly

[Kent Johnson]

chris wrote:
> We have a number of TestCase classes that have multiple test methods.
> We are interested in removing any of the individual test methods on the
> fly (dynamically, at runtime, whatever).
> 
> We currently have an "isSupported" method in the TestCase classes that
> return a bool by which the greater test harness decides whether to run
> the enclosed test methods or not.  We would like to have
> per-test-method granularity, however, for essentially skipping that
> particular test method;  basically another isSupported call within the
> individual methods.  We took a quick look at such options as:
> generating the entire test suite, then iterating through and renaming
> SomeTestClass.testSomeTest to SomeTestClass.SKIPsomeTest, and seeing if
> PyUnit would skip it (since the method name no longer starts with
> "test").  But this seemed pretty unwieldy.  We have also considered
> breaking up the test class to a number of smaller test classes and
> calling isSupported with that finer-granularity set of test classes.
> That is probably the easiest way, but we do still want to consider
> alternatives.

ISTM you could write a custom TestLoader that filters the test names, then pass that loader to unittest.main(). For example, assuming a classmethod or staticmethod on the test case that filters test case names, something like this (not tested):

def MyTest(TestCase):
  @staticmethod
  def isSupportedTest(testName):
    return True

  def testSomething...

class FilteringTestLoader(TestLoader):
  def getTestCaseNames(self, testCaseClass):
    names = TestLoader.getTestCaseNames(self, testCaseClass)
    names = filter(testCaseClass.isSupportedTest, names)
    return names

unittest.main(testLoader=FilteringTestLoader())

You could do something similar with a FilteringTestSuite if that fits your harness better.

Kent