23.3.4 Classes and functions
Instances of the TestCase class represent the smallest
testable units in the unittest universe. This class is
intended to be used as a base class, with specific tests being
implemented by concrete subclasses. This class implements the
interface needed by the test runner to allow it to drive the
test, and methods that the test code can use to check for and
report various kinds of failure.
Each instance of TestCase will run a single test method:
the method named methodName. If you remember, we had an
earlier example that went something like this:
suite = unittest.TestSuite()
Here, we create two instances of WidgetTestCase, each of
which runs a single test.
methodName defaults to
setUp[, tearDown[, description]]])|
This class implements the portion of the TestCase interface
which allows the test runner to drive the test, but does not provide
the methods which test code can use to check and report errors.
This is used to create test cases using legacy test code, allowing
it to be integrated into a unittest-based test
This class represents an aggregation of individual tests cases and
test suites. The class presents the interface needed by the test
runner to allow it to be run as any other test case. Running a
TestSuite instance is the same as iterating over the suite,
running each test individually.
If tests is given, it must be an iterable of individual test cases or
other test suites that will be used to build the suite initially.
Additional methods are provided to add test cases and suites to the
collection later on.
This class is responsible for loading tests according to various
criteria and returning them wrapped in a TestSuite.
It can load all tests within a given module or TestCase
This class is used to compile information about which tests have succeeded
and which have failed.
Instance of the TestLoader class intended to be shared. If no
customization of the TestLoader is needed, this instance can
be used instead of repeatedly creating new instances.
A basic test runner implementation which prints results on standard
error. It has a few configurable parameters, but is essentially
very simple. Graphical applications which run test suites should
provide alternate implementations.
A command-line program that runs a set of tests; this is primarily
for making test modules conveniently executable. The simplest use
for this function is to include the following line at the end of a
if __name__ == '__main__':
In some cases, the existing tests may have been written using the
doctest module. If so, that module provides a
DocTestSuite class that can automatically build
unittest.TestSuite instances from the existing
New in version 2.3.
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