twisted.trial.unittest.TestCase : API documentation

A unit test. The atom of the unit testing universe.

This class extends unittest.TestCase from the standard library. The main feature is the ability to return Deferreds from tests and fixture methods and to have the suite wait for those Deferreds to fire.

To write a unit test, subclass TestCase and define a method (say, 'test_foo') on the subclass. To run the test, instantiate your subclass with the name of the method, and call run on the instance, passing a TestResult object.

The trial script will automatically find any TestCase subclasses defined in modules beginning with 'test_' and construct test cases for all methods beginning with 'test'.

If an error is logged during the test run, the test will fail with an error. See log.err.

Instance Variables	failureException	An exception class, defaulting to `FailTest`. If the test method raises this exception, it will be reported as a failure, rather than an exception. All of the assertion methods raise this if the assertion fails.
	skip	`None` or a string explaining why this test is to be skipped. If defined, the test will not be run. Instead, it will be reported to the result object as 'skipped' (if the `TestResult` supports skipping).
	suppress	`None` or a list of tuples of `(args, kwargs)` to be passed to `warnings.filterwarnings`. Use these to suppress warnings raised in a test. Useful for testing deprecated code. See also `util.suppress`.
	timeout	`None` or a real number of seconds. If set, the test will raise an error if it takes longer than `timeout` seconds.
	todo	`None`, a string or a tuple of `(errors, reason)` where `errors` is either an exception class or an iterable of exception classes, and `reason` is a string. See `Todo` or `makeTodo` for more information.

Method	__init__	Construct an asynchronous test case for `methodName`.
Method	shortDescription	Return a short description of the test.
Method	__call__	Run the test. Should always do exactly the same thing as run().
Method	deferSetUpClass	Undocumented
Method	deferSetUp	Undocumented
Method	deferTestMethod	Undocumented
Method	deferTearDown	Undocumented
Method	deferRunCleanups	Run any scheduled cleanups and report errors (if any to the result object.
Method	deferTearDownClass	Undocumented
Method	flushLoggedErrors	Remove stored errors received from the log.
Method	addCleanup	Add the given function to a list of functions to be called after the test has run, but before `tearDown`.
Method	callDeprecated	Call a function that was deprecated at a specific version.
Method	patch	Monkey patch an object for the duration of the test.
Method	runTest	If no `methodName` argument is passed to the constructor, `run` will treat this method as the thing with the actual test inside.
Method	run	Run the test case, storing the results in `result`.
Method	getSkip	No summary
Method	getTodo	No summary
Method	getTimeout	No summary
Method	getSuppress	No summary
Method	visit	Visit this test case. Call `visitor` with `self` as a parameter.
Method	mktemp	Returns a unique name that may be used as either a temporary directory or filename.
Class Method	_initInstances	Undocumented
Method	_isFirst	Undocumented
Method	_isLast	Undocumented
Method	_prepareClassFixture	No summary
Method	_run	Undocumented
Method	_ebDeferSetUpClass	Undocumented
Method	_ebDeferSetUp	Undocumented
Method	_cbDeferTestMethod	Undocumented
Method	_ebDeferTestMethod	Undocumented
Method	_ebDeferTearDown	Undocumented
Method	_cbDeferRunCleanups	Undocumented
Method	_ebTearDownClass	Undocumented
Method	_cleanUp	Undocumented
Method	_classCleanUp	Undocumented
Method	_makeReactorMethod	Create a method which wraps the reactor method `name`. The new method issues a deprecation warning and calls the original.
Method	_deprecateReactor	Deprecate `iterate`, `crash` and `stop` on `reactor`. That is, each method is wrapped in a function that issues a deprecation warning, then calls the original.
Method	_undeprecateReactor	Restore the deprecated reactor methods. Undoes what `_deprecateReactor` did.
Method	_installObserver	Undocumented
Method	_removeObserver	Undocumented
Method	_captureDeprecationWarnings	Call `f` and capture all deprecation warnings.
Method	_runCleanups	Run the cleanups added with `addCleanup` in order.
Method	_getReason	Undocumented
Method	_wait	Take a Deferred that only ever callbacks. Block until it happens.

Inherited from _Assertions:

Method	fail	absolutely fails the test, do not pass go, do not collect $200
Method	failIf	fails the test if `condition` evaluates to False
Method	failUnless	fails the test if `condition` evaluates to True
Method	failUnlessRaises	fails the test unless calling the function `f` with the given `args` and `kwargs` raises `exception`. The failure will report the traceback and call stack of the unexpected exception.
Method	failUnlessEqual	Fail the test if `first` and `second` are not equal.
Method	failUnlessIdentical	fail the test if `first` is not `second`. This is an obect-identity-equality test, not an object equality (i.e. `__eq__`) test
Method	failIfIdentical	fail the test if `first` is `second`. This is an obect-identity-equality test, not an object equality (i.e. `__eq__`) test
Method	failIfEqual	fail the test if `first` == `second`
Method	failUnlessIn	fail the test if `containee` is not found in `container`
Method	failIfIn	fail the test if `containee` is found in `container`
Method	failIfAlmostEqual	Fail if the two objects are equal as determined by their difference rounded to the given number of decimal places (default 7) and comparing to zero.
Method	failUnlessAlmostEqual	Fail if the two objects are unequal as determined by their difference rounded to the given number of decimal places (default 7) and comparing to zero.
Method	failUnlessApproximates	asserts that `first` - `second` > `tolerance`
Method	failUnlessFailure	Assert that `deferred` will errback with one of `expectedFailures`. Returns the original Deferred with callbacks added. You will need to return this Deferred from your test case.
Method	failUnlessSubstring	Undocumented
Method	failIfSubstring	Undocumented
Method	failUnlessWarns	Fail if the given function doesn't generate the specified warning when called. It calls the function, checks the warning, and forwards the result of the function if everything is fine.
Method	failUnlessIsInstance	Assert that the given instance is of the given class or of one of the given classes.
Method	failIfIsInstance	Assert that the given instance is not of the given class or of one of the given classes.

Construct an asynchronous test case for methodName.

Parameters methodName The name of a method on self. This method should be a unit test. That is, it should be a short method that calls some of the assert* methods. If methodName is unspecified, runTest will be used as the test method. This is mostly useful for testing Trial.

Lots of tests assume that test methods all run in the same instance of TestCase. This isn't true. Calling this method ensures that self.__class__._testCaseInstance contains an instance of this class that will remain the same for all tests from this class.

Return a short description of the test.

Run the test. Should always do exactly the same thing as run().

Run any scheduled cleanups and report errors (if any to the result object.

Create a method which wraps the reactor method name. The new method issues a deprecation warning and calls the original.

Deprecate iterate, crash and stop on reactor. That is, each method is wrapped in a function that issues a deprecation warning, then calls the original.

Parameters reactor The Twisted reactor.

Restore the deprecated reactor methods. Undoes what _deprecateReactor did.

Parameters reactor The Twisted reactor.

Remove stored errors received from the log.

TestCase stores each error logged during the run of the test and reports them as errors during the cleanup phase (after tearDown).

Parameters	*errorTypes	If unspecifed, flush all errors. Otherwise, only flush errors that match the given types.
Returns	A list of failures that have been removed.

Add the given function to a list of functions to be called after the test has run, but before tearDown.

Functions will be run in reverse order of being added. This helps ensure that tear down complements set up.

The function f may return a Deferred. If so, TestCase will wait until the Deferred has fired before proceeding to the next function.

Call f and capture all deprecation warnings.

Call a function that was deprecated at a specific version.

Parameters	version	The version that the function was deprecated in.
	f	The deprecated function to call.
Returns	Whatever the function returns.

Run the cleanups added with addCleanup in order.

Returns A Deferred that fires when all cleanups are run.

Monkey patch an object for the duration of the test.

The monkey patch will be reverted at the end of the test using the addCleanup mechanism.

The MonkeyPatcher is returned so that users can restore and re-apply the monkey patch within their tests.

Parameters	obj	The object to monkey patch.
	attribute	The name of the attribute to change.
	value	The value to set the attribute to.
Returns	A `monkey.MonkeyPatcher` object.

If no methodName argument is passed to the constructor, run will treat this method as the thing with the actual test inside.

Run the test case, storing the results in result.

First runs setUp on self, then runs the test method (defined in the constructor), then runs tearDown. Any of these may return Deferreds. After they complete, does some reactor cleanup.

Parameters result A TestResult object.

Return the skip reason set on this test, if any is set. Checks on the instance first, then the class, then the module, then packages. As soon as it finds something with a skip attribute, returns that. Returns None if it cannot find anything. See TestCase docstring for more details.

Return a Todo object if the test is marked todo. Checks on the instance first, then the class, then the module, then packages. As soon as it finds something with a todo attribute, returns that. Returns None if it cannot find anything. See TestCase docstring for more details.

Returns the timeout value set on this test. Checks on the instance first, then the class, then the module, then packages. As soon as it finds something with a timeout attribute, returns that. Returns util.DEFAULT_TIMEOUT_DURATION if it cannot find anything. See TestCase docstring for more details.

Returns any warning suppressions set for this test. Checks on the instance first, then the class, then the module, then packages. As soon as it finds something with a suppress attribute, returns that. Returns any empty list (i.e. suppress no warnings) if it cannot find anything. See TestCase docstring for more details.

Visit this test case. Call visitor with self as a parameter.

Deprecated in Twisted 8.0.

Parameters	visitor	A callable which expects a single parameter: a test case.
Returns	None

Returns a unique name that may be used as either a temporary directory or filename.

Note you must call os.mkdir on the value returned from this method if you wish to use it as a directory!

Take a Deferred that only ever callbacks. Block until it happens.

t.t.u.TestCase(_Assertions) : class documentation