The testrunner module is used to run automated tests defined using the unittest framework. Its primary feature is that it finds tests by searching directory trees. It doesn’t require the manual concatenation of specific test suites. It is highly customizable and should be usable with any project. In addition to finding and running tests, it provides the following additional features:

  • Test filtering using specifications of:

    • test packages within a larger tree

    • regular expression patterns for test modules

    • regular expression patterns for individual tests

  • Organization of tests into levels and layers

    Sometimes, tests take so long to run that you don’t want to run them on every run of the test runner. Tests can be defined at different levels. The test runner can be configured to only run tests at a specific level or below by default. Command-line options can be used to specify a minimum level to use for a specific run, or to run all tests. Individual tests or test suites can specify their level via a level attribute. where levels are integers increasing from 1.

    Most tests are unit tests. They don’t depend on other facilities, or set up whatever dependencies they have. For larger applications, it’s useful to specify common facilities that a large number of tests share. Making each test set up and and tear down these facilities is both ineffecient and inconvenient. For this reason, we’ve introduced the concept of layers, based on the idea of layered application architectures. Software build for a layer should be able to depend on the facilities of lower layers already being set up. For example, Zope defines a component architecture. Much Zope software depends on that architecture. We should be able to treat the component architecture as a layer that we set up once and reuse. Similarly, Zope application software should be able to depend on the Zope application server without having to set it up in each test.

    The test runner introduces test layers, which are objects that can set up environments for tests within the layers to use. A layer is set up before running the tests in it. Individual tests or test suites can define a layer by defining a layer attribute, which is a test layer.

  • Reporting

  • Analysis of test execution