23.3.7 TestResult Objects

A TestResult object stores the results of a set of tests. The TestCase and TestSuite classes ensure that results are properly recorded; test authors do not need to worry about recording the outcome of tests.

Testing frameworks built on top of unittest may want access to the TestResult object generated by running a set of tests for reporting purposes; a TestResult instance is returned by the TestRunner.run() method for this purpose.

TestResult instances have the following attributes that will be of interest when inspecting the results of running a set of tests:

errors: A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents a test which raised an unexpected exception. Changed in version 2.2: Contains formatted tracebacks instead of sys.exc_info() results.

failures: A list containing 2-tuples of TestCase instances and strings holding formatted tracebacks. Each tuple represents a test where a failure was explicitly signalled using the TestCase.fail*() or TestCase.assert*() methods. Changed in version 2.2: Contains formatted tracebacks instead of sys.exc_info() results.

testsRun: The total number of tests run so far.

wasSuccessful( ): Returns True if all tests run so far have passed, otherwise returns False.

stop( ): This method can be called to signal that the set of tests being run should be aborted by setting the TestResult's shouldStop attribute to True. TestRunner objects should respect this flag and return without running any additional tests.
For example, this feature is used by the TextTestRunner class to stop the test framework when the user signals an interrupt from the keyboard. Interactive tools which provide TestRunner implementations can use this in a similar manner.

The following methods of the TestResult class are used to maintain the internal data structures, and may be extended in subclasses to support additional reporting requirements. This is particularly useful in building tools which support interactive reporting while tests are being run.

startTest( test): Called when the test case test is about to be run.
The default implementation simply increments the instance's testsRun counter.

stopTest( test): Called after the test case test has been executed, regardless of the outcome.
The default implementation does nothing.

addError( test, err): Called when the test case test raises an unexpected exception err is a tuple of the form returned by sys.exc_info(): (type, value, traceback).
The default implementation appends (test, err) to the instance's errors attribute.

addFailure( test, err): Called when the test case test signals a failure. err is a tuple of the form returned by sys.exc_info(): (type, value, traceback).
The default implementation appends (test, err) to the instance's failures attribute.

addSuccess( test): Called when the test case test succeeds.
The default implementation does nothing.

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