Auto-grading is a powerful tool that saves teachers time and provides students with feedback regarding the correctness of their solution before they submit it for a grade.
All of this auto-grading magic can be accomplished with unit testing -- test whether parts (units) of a students code work properly by asserting that they meet certain conditions (equal to a predetermined value, produce a result in a given range, etc.).
The basic building blocks of unit testing are test cases — single scenarios that must be set up and checked for correctness.
The simplest TestCase subclass will simply implement a test method (i.e. a method whose name starts with test) in order to perform specific testing code:
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deftest_default_case(self):
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# Your test case logic here (replace the example assertion below)
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# You may also rename this to any function in the form of 'test_your_test_name(self):'
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self.assertTrue(True)
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Note that in order to test something, we use one of the assert*() methods provided by the TestCase base class. If the test fails, an exception will be raised with an explanatory message, and unittest will identify the test case as a failure. Any other exceptions will be treated as errors.
Tests can be numerous, and their set-up can be repetitive. Luckily, we can factor out set-up code by implementing a method called setUp(), which the testing framework will automatically call for every single test we run:
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defsetUp(self):
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# Setup code here (if required, replace the 'pass')
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pass
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Similarly, we can provide a tearDown() method that tidies up after the test method has been run:
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deftearDown(self):
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# Teardown code here (if required, replace the 'pass')
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pass
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If setUp() succeeded, tearDown() will be run whether the test method succeeded or not.
Java - JUnit
TODO
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@Test
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publicvoidtestDefaultCase(){
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// You may rename this method to better suit the purpose of your test case
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// Your test case logic here
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}
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@Before
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publicvoidsetUp(){
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// Setup code here (if required)
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}
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@After
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publicvoidtearDown(){
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// Teardown code here (if required)
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}
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Created and curated by Joe Mazzone
Joe Mazzone, Computer and Software Engineering instructor at William M. Davies, Jr. Career and Technical High School in Lincoln, Rhode Island