Unit Test Quickstart

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Revision as of 11:07, 6 November 2007 by Jgsack (talk | contribs) (Unit Test Quickstart)
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This page gives some simple recipes and tips for writing unit tests in the Gramps source code tree.

First, some general procedural and structural notes

  • unit tests are usually created to verify correct functional behavior of a single module of source code.
  • test code goes in a test subdirectory of the subject module's directory
  • the test module should be named with a suffix _test so that it can be found by automatic regression test tools.
  • the leading part of the test will commonly be named the same as the basename (or a variant) of the module under test, leading, for example, to the following files
src/A/B/module.py
src/A/B/test/module_test.py
  • the test subdirectory can contain data or helper programs as required
  • the test and such supplementary elements that are persistent will be maintained as part of the source control system.
  • the test module can create and delete test data during execution. Commonly this would go in a deeper subdir, named to avoid collision with other test programs.

...more to come...

Simple Code Recipes

There are only a few firm requirements to fit into the framework. Here is a simple test module that may be considered something of a template.

import unittest
# import this test support utility before importing the module under test
from test import test_util
parent_dir = test_util.path_append_parent # enables the following import
import MyModule 

# look in test/test_util.py for other conveniences (and suggest more ideas)
this_dir = test_util.abspath()
data_dir = test_util.make_subdir("MyModule_test_data")

# unittest requires a TestCase class containing test function members 
# optional setUp() and tearDown() functions can perform pre/post test housekeeping
class Test_top(unittest.TestCase):
  
  def setUp(self):
    ...
  def tearDown(self):
    ...
  def test_function_x(self):
     ..do stuff..
     self.assertTrue(expression, "message to display on failure")
     #see other assert and fail functions in the unittest module
  ..more defs for more tests, more classes for possible grouping logic..
if __test__ == "__main__":
  unittest.main()