Randomly select functions

Question

I am writing a test script which contains different functions for different tests. I would like to be able to randomly select a test to run. I have already achieved this with the following function...

test_options = ("AOI", "RMODE")

def random_test(test_options, control_obj):
  ran_test_opt = choice(test_options)

  if ran_test_opt.upper() == "AOI":
     logging.debug("Random AOI Test selected")
     random_aoi()
  elif ran_test_opt.upper() == "RMODE":
    logging.debug("Random Read Mode Test selected")
    random_read_mode(control_obj)

However, I want to be to add further test functions without having to modify the random test select function. All I would like to do is add in the test function to the script. Additionally I would also like a way to selecting which test will be included in the random selection. This is what the variable test_options does. How would I go about changing my random generate function to achieve this?

EDIT: I got around the fact that all the tests might need different arguments by including them all in a test class. All the arguments will be passed into the init and the test functions will refer to them using "self." when they need a specific variable...

class Test(object):
  """A class that contains and keeps track of the tests and the different modes"""

  def __init__(self, parser, control_obj):
    self.parser = parser
    self.control_obj = control_obj

  def random_test(self):
    test_options = []
    for name in self.parser.options('Test_Selection'):
        if self.parser.getboolean('Test_Selection', name):
            test_options.append(name.lower())

    ran_test_opt = choice(test_options)
    ran_test_func = getattr(self, ran_test_opt)
    ran_test_func()

  #### TESTS ####
  def random_aoi(self):
    logging.info("Random AOI Test")
    self.control_obj.random_readout_size()

  def random_read_mode(self):
    logging.info("Random Readout Mode Test")
    self.control_obj.random_read_mode()

Answer 1

You can create a list of functions in python which you can call:

test_options = (random_aoi, random_read_mode)

def random_test(test_options, control_obj):
    ran_test_opt = choice(test_options)
    ran_test_opt(control_obj) # call the randomly selected function

You have to make each function take the same arguments this way, so you can call them all the same way.

Answer 2

If you need to have some human readable names for the functions, you can store them in a dictionary, together with the function. I expect that you pass the control_obj to every function.

EDIT: This seems to be identical to the answer by @Ikke, but uses the dictionary instead of a list of functions.

>>> test_options = {'AOI': random_aoi, 'RMODE': random_read_mode}

>>> def random_test(test_options, control_obj):
...    ran_test_opt = test_options[choice(test_options.keys())]
...    ran_test_opt(control_obj)

Or you could pick out a test from test_options.values(). The 'extra' call to list() is because in python 3.x, dict.values() returns an iterator.

>>> ran_test_opt = choice(list(test_options.values()))