neutron/HACKING.rst
Nguyen Phuong An 9afb9ca598 Prevent use filter(lambda obj: test(obj), data)
In Python3 [1], if we need filter on python3, replace
filter(lambda obj: test(obj), data) with:
[obj for obj in data if test(obj)]. This patch replaces
filter function and introduces a hacking rule to prevent
using filter in future.

[1] https://wiki.openstack.org/wiki/Python3

Change-Id: I83d22108c02f8da007a7233e71a4a7fb833170ec
2016-09-14 16:23:32 +07:00

2.4 KiB

Neutron Style Commandments

Neutron Specific Commandments

  • [N319] Validate that debug level logs are not translated
  • [N320] Validate that LOG messages, except debug ones, have translations
  • [N321] Validate that jsonutils module is used instead of json
  • [N322] Detect common errors with assert_called_once_with
  • [N324] Prevent use of deprecated contextlib.nested.
  • [N325] Python 3: Do not use xrange.
  • [N326] Python 3: do not use basestring.
  • [N327] Python 3: do not use dict.iteritems.
  • [N328] Detect wrong usage with assertEqual
  • [N329] Method's default argument shouldn't be mutable
  • [N330] Use assertEqual(empty, observed) instead of

    assertEqual(observed, empty)

  • [N331] Detect wrong usage with assertTrue(isinstance()).
  • [N332] Use assertEqual(expected_http_code, observed_http_code) instead of

    assertEqual(observed_http_code, expected_http_code).

  • [N333] Validate that LOG.warning is used instead of LOG.warn. The latter is deprecated.
  • [N334] Use unittest2 uniformly across Neutron.
  • [N340] Check usage of <module>.i18n (and neutron.i18n)
  • [N341] Check usage of _ from python builtins
  • [N342] String interpolation should be delayed at logging calls.
  • [N344] Python 3: Do not use filter(lambda obj: test(obj), data). Replace it with [obj for obj in data if test(obj)].

Creating Unit Tests

For every new feature, unit tests should be created that both test and (implicitly) document the usage of said feature. If submitting a patch for a bug that had no unit test, a new passing unit test should be added. If a submitted bug fix does have a unit test, be sure to add a new one that fails without the patch and passes with the patch.

All unittest classes must ultimately inherit from testtools.TestCase. In the Neutron test suite, this should be done by inheriting from neutron.tests.base.BaseTestCase. If the third party unittest library has to be used directly then it is recommended to use unittest2 as it contains bug fixes to unittest for all versions of Python prior to version 3.5.

All setUp and tearDown methods must upcall using the super() method. tearDown methods should be avoided and addCleanup calls should be preferred. Never manually create tempfiles. Always use the tempfile fixtures from the fixture library to ensure that they are cleaned up.