# unittest --- Unit testing framework — Skipping tests and expected failures

> Unittest supports skipping individual test methods and even whole classes of tests.

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- Canonical URL: <https://wikikv.com/k/ref-python-932d69d42c5c630943da>
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- Updated: `2026-08-16T09:31:34.777363+00:00`
- Tags: `reference-seed`, `python`, `library`, `unittest`, `unit`, `testing`, `framework`, `skipping`, `tests`, `expected`, `failures`

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## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Unittest supports skipping individual test methods and even whole classes of tests. In addition, it supports marking a test as an "expected failure," a test that is broken and will fail, but shouldn't be counted as a failure on a TestResult.

Skipping a test is simply a matter of using the skip decorator or one of its conditional variants, calling TestCase.skipTest within a ~TestCase.setUp or test method, or raising SkipTest directly.

Basic skipping looks like this

class MyTestCase(unittest.TestCase)

This is the output of running the example above in verbose mode

test_format (main.MyTestCase.test_format) ... skipped 'not supported in this library version' test_nothing (main.MyTestCase.test_nothing) ... skipped 'demonstrating skipping' test_maybe_skipped (main.MyTestCase.test_maybe_skipped) ... skipped 'external resource not available' test_windows_support (main.MyTestCase.test_windows_support) ... skipped 'requires Windows'

Classes can be skipped just like methods

@unittest.skip("showing class skipping") class MySkippedTestCase(unittest.TestCase): def test_not_run(self): pass

TestCase.setUp can also skip the test. This is useful when a resource that needs to be set up is not available.

Expected failures use the expectedFailure decorator.

class ExpectedFailureTestCase(unittest.TestCase): @unittest.expectedFailure def test_fail(self): self.assertEqual(1, 0, "broken")

It's easy to roll your own skipping decorators by making a decorator that calls skip on the test when it wants it to be skipped. This decorator skips the test unless the passed object has a certain attribute

def skipUnlessHasattr(obj, attr): if hasattr(obj, attr): return lambda func: func return unittest.skip("{!r} doesn't have {!r}".format(obj, attr))

The following decorators and exception implement test skipping and expected failures

Unconditionally skip the decorated test. reason should describe why the test is being skipped.

Skip the decorated test if condition is true.

Skip the decorated test unless condition is true.

Mark the test as an expected failure or error. If the test fails or errors in the test function itself (rather than in one of the test fixture methods) then it will be considered a success. If the test passes, it will be considered a failure.

This exception is raised to skip a test. …

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