py.test - PyCon UK 2008

Notes

  • Automatically collects and executes tests.

  • Install

    easy_install -U py

  • Not inherited from a test class.

  • To create a temporary directory.

    datadir = py.test.ensuretemp("folder-name")

    Updates environment so we can easily cd into this folder.

  • Just use a simple assert to check the condition:

    pkg = datadir.ensure('pkg'), dir=1)
pkg.ensure("__init__.py")
assert pkg.pypkpath() == pkg

  • To run the tests:

    py.test test.py
py.test test.py --showlocals

  • To only run a test if it is running in Windows:

    disabled = py.std.sys.platform != 'win32'

  • Generative (Parametized) tests (creating three tests with yield):

    def check(x):
    assert x >= 0

def test_gen():
    for x in 1,2,3:
        yield check, x

  • stdout/stderr is captured per test.

  • -l or --showlocals

  • --pdb directly debug.

  • -k, select test be keyword.

  • -v, verbose output.

  • -test-name everything that is not this test

  • -x or exitfirst, exist on first failure.

  • --looponfailing, only re-run failing test parts.

  • setup_class(cls) and setup_method(self, method), to set-up for the class and for the method (also setup_module).

    Can get the class name (cls.__name__) and the method name, method.__name__.

    Can set attributes on the class and method objects.

    Could use the set-up module method for deploying or for creating expensive resources.

  • Skip tests:

    if sys.platform != "win32":
  py.test.skip("win32 required")

    You can also place such calls in setup functions.

  • Can add project level attributes such as --runslowtests.

  • doctests, is getting better… py.test automatically collects test_doc.txt files:

    Will automatically run doctests.

  • easy_install, will get a slightly older version.

  • Customise:

    • Modify test collection process

    • Add command line options.

    • register to reporting files (version 1.0)

    • write conftest.py files.

    • for debugging:

      py.test --collectonly

  • Directory.. collect files in a folder… and loads of other things…

  • Place conftest.py file in a directory.

  • Plugins:

    • Generate an html file, showing the failures (plugin I think).

    • Can run JavaScript tests using Spider Monkey.

    • Can run cross platform tests.

    • Can run standard unittest methods.