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# ``twisted`.`trial`.`unittest`.`TestCase``

class documentation

`class TestCase(SynchronousTestCase): (source)`

Constructor: `TestCase(methodName)`

Implements interfaces: `twisted.trial.itrial.ITestCase`

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

This class extends `SynchronousTestCase` which extends `unittest.TestCase` from the standard library. The main feature is the ability to return `Deferred`s from tests and fixture methods and to have the suite wait for those `Deferred`s to fire. Also provides new assertions such as `assertFailure`.

Method | `__call__` | Run the test. Should always do exactly the same thing as run().
Method | `__init__` | Construct an asynchronous test case for `methodName`.
Method | `addCleanup` | Extend the base cleanup feature with support for cleanup functions which return Deferreds.
Method | `assertFailure` | Fail if `deferred` does not errback with one of `expectedFailures`. Returns the original Deferred with callbacks added. You will need to return this Deferred from your test case.
Method | `getSuppress` | Undocumented
Method | `getTimeout` | 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`...
Instance Variable | `timeout` | A real number of seconds. If set, the test will raise an error if it takes longer than `timeout` seconds. If not set, util.DEFAULT_TIMEOUT_DURATION is used.
Method | `_classCleanUp` | Undocumented
Method | `_cleanUp` | Undocumented
Method | `_deferRunCleanups` | Run any scheduled cleanups and report errors (if any) to the result. object.
Async Method | `_deferSetUp` | Undocumented
Async Method | `_deferSetUpAndRun` | Execute the setUp and run part of a test. Teardown and cleanups are not executed.
Async Method | `_deferTearDown` | Undocumented
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 | `_ebDeferTestMethod` | Undocumented
Method | `_makeReactorMethod` | Create a method which wraps the reactor method `name`. The new method issues a deprecation warning and calls the original.
Method | `_run` | Run a single method, either a test method or fixture.
Method | `_runFixturesAndTest` | Really run `setUp`, the test method, and `tearDown`. Any of these may return `defer.Deferred`s. After they complete, do some reactor cleanup.
Method | `_undeprecateReactor` | Restore the deprecated reactor methods. Undoes what `_deprecateReactor` did.
Method | `_wait` | Take a Deferred that only ever callbacks. Block until it happens.
Instance Variable | `_passed` | Undocumented
Instance Variable | `_reactorMethods` | Undocumented
Instance Variable | `_timedOut` | Undocumented
Instance Variable | `_twistedPrivateNeedsTearDown` | Undocumented
Instance Variable | `_twistedPrivateScheduler` | Undocumented

Inherited from `SynchronousTestCase`:

Method | `__eq__` | Override the comparison defined by the base TestCase which considers instances of the same class with the same _testMethodName to be equal. Since trial puts TestCase instances into a set, that definition of comparison makes it impossible to run the same test method twice...
Method | `__hash__` | Undocumented
Method | `callDeprecated` | Call a function that should have been deprecated at a specific version and in favor of a specific alternative, and assert that it was thusly deprecated.
Method | `flushLoggedErrors` | Remove stored errors received from the log.
Method | `flushWarnings` | Remove stored warnings from the list of captured warnings and return them.
Method | `getDeprecatedModuleAttribute` | Retrieve a module attribute which should have been deprecated, and assert that we saw the appropriate deprecation warning.
Method | `getSkip` | 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 in a tuple (...
Method | `getTodo` | 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 ...
Method | `mktemp` | Create a new path name which can be used for a new file or directory.
Method | `patch` | Monkey patch an object for the duration of the test.
Method | `run` | Run the test case, storing the results in `result`.
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 | `shortDescription` | Undocumented
Instance Variable | `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.
Instance Variable | `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).
Instance Variable | `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`.
Instance Variable | `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 | `_getSkipReason` | Return the reason to use for skipping a test method.
Method | `_getSuppress` | 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. ...
Method | `_installObserver` | Undocumented
Method | `_removeObserver` | Undocumented
Method | `_runCleanups` | Synchronously run any cleanups which have been added.
Instance Variable | `_cleanups` | Undocumented
Instance Variable | `_observer` | Undocumented
Instance Variable | `_parents` | Undocumented
Instance Variable | `_testMethodName` | Undocumented
Instance Variable | `_warnings` | Undocumented

Inherited from `_Assertions` (via `SynchronousTestCase`):

Method | `assertAlmostEqual` | 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 | `assertApproximates` | Fail if `first` - `second` > `tolerance`
Method | `assertEqual` | Fail the test if `first` and `second` are not equal.
Method | `assertFalse` | Fail the test if `condition` evaluates to True.
Method | `assertIn` | Fail the test if `containee` is not found in `container`.
Method | `assertIs` | Fail the test if `first` is not `second`. This is an obect-identity-equality test, not an object equality (i.e. `__eq__`) test.
Method | `assertIsInstance` | Fail if `instance` is not an instance of the given class or of one of the given classes.
Method | `assertIsNot` | Fail the test if `first` is `second`. This is an obect-identity-equality test, not an object equality (i.e. `__eq__`) test.
Method | `assertNoResult` | Assert that `deferred` does not have a result at this point.
Method | `assertNotAlmostEqual` | 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 | `assertNotEqual` | Fail the test if `first` == `second`.
Method | `assertNotIn` | Fail the test if `containee` is found in `container`.
Method | `assertNotIsInstance` | Fail if `instance` is an instance of the given class or of one of the given classes.
Method | `assertNotSubstring` | Fail if `astring` contains `substring`.
Method | `assertRaises` | Fail 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 | `assertSubstring` | Fail if `substring` does not exist within `astring`.
Method | `assertTrue` | Fail the test if `condition` evaluates to False.
Method | `assertWarns` | 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 | `fail` | Absolutely fail the test. Do not pass go, do not collect $200.
Method | `failureResultOf` | Return the current failure result of `deferred` or raise `self.failureException`.
Method | `successResultOf` | Return the current success result of `deferred` or raise `self.failureException`.

def __call__(self, *args, **kwargs): (source)
from `twisted.trial.itrial.ITestCase`

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

def __init__(self, methodName='runTest'): (source)
overrides `twisted.trial.unittest.SynchronousTestCase.__init__`

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, `SynchronousTestCase.runTest` will be used as the test method. This is mostly useful for testing Trial.

def addCleanup(self, f: `Callable[_P, object]`, *args: `_P.args`, **kwargs: `_P.kwargs`): (source)
overrides `twisted.trial.unittest.SynchronousTestCase.addCleanup`

Extend the base cleanup feature with support for cleanup functions which return Deferreds.

If the function `f` returns a Deferred, `TestCase` will wait until the Deferred has fired before proceeding to the next function.

If the function takes more than `timeout` settings, then the test will raise an error.

def assertFailure(self, deferred: `defer.Deferred[_T]`, *expectedFailures: `type[BaseException]`) -> `defer.Deferred[_T]`: (source)

Fail if `deferred` does not errback with one of `expectedFailures`. Returns the original Deferred with callbacks added. You will need to return this Deferred from your test case.

def getSuppress(self): (source)

Undocumented

def getTimeout(self): (source)

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.

timeout = (source)

A real number of seconds. If set, the test will raise an error if it takes longer than `timeout` seconds. If not set, util.DEFAULT_TIMEOUT_DURATION is used.

def _classCleanUp(self, result): (source)

Undocumented

def _cleanUp(self, result): (source)

Undocumented

@defer.inlineCallbacks
def _deferRunCleanups(self, result): (source)

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

async def _deferSetUp(self, result): (source)

Undocumented

async def _deferSetUpAndRun(self, result): (source)

Execute the setUp and run part of a test. Teardown and cleanups are not executed.

async def _deferTearDown(self, result): (source)

Undocumented

def _deprecateReactor(self, reactor): (source)

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.

def _ebDeferTestMethod(self, f, result): (source)

Undocumented

def _makeReactorMethod(self, name): (source)

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

def _run(self, func, funcDescription, result): (source)
overrides `twisted.trial.unittest.SynchronousTestCase._run`

Run a single method, either a test method or fixture.

Parameters
func | Undocumented
funcDescription | Undocumented
result | The TestResult instance to which to report results.
suppress | Any warnings to suppress, as defined by the `suppress` attribute on this method, test case, or the module it is defined in.
todo | Any expected failure or failures, as defined by the `todo` attribute on this method, test case, or the module it is defined in.
method | The method to run.

Returns
`True` if the method fails and no further method/fixture calls should be made, `False` otherwise.

def _runFixturesAndTest(self, result): (source)
overrides `twisted.trial.unittest.SynchronousTestCase._runFixturesAndTest`

Really run `setUp`, the test method, and `tearDown`. Any of these may return `defer.Deferred`s. After they complete, do some reactor cleanup.

Parameters
result | A `TestResult` object.

def _undeprecateReactor(self, reactor): (source)

Restore the deprecated reactor methods. Undoes what `_deprecateReactor` did.

Parameters
reactor | The Twisted reactor.

def _wait(self, d, running=_wait_is_running): (source)

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

_passed: `bool` = (source)
overrides `twisted.trial.unittest.SynchronousTestCase._passed`

Undocumented

_reactorMethods: `dict` = (source)

Undocumented

_timedOut: `bool` = (source)

Undocumented

_twistedPrivateNeedsTearDown: `bool` = (source)

Undocumented

_twistedPrivateScheduler = (source)

Undocumented