FIT4004 Lecture Notes - Lecture 8: Test Method, List Of Unit Testing Frameworks, Test Stub
25 Jun 2018
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Lecture 8 - Unit Tesng
Unit :
●Small
●Self-contained chunks of related funconality
●In OOD units are usually Classes
Unit tests :
●Wrien by the developers of the unit
●Almost always automated
Test method
Paern is :
1. Do something
2. Assert that the results as expected
Do unit tests executes in a parcular order?
No
What method exists to set up a test case?
setup()
What method exists for clean up aer a test?
tearDown()
How would you test that a unit fails as expected?
assertRaises()
Side Effects of tesng code that calls external modules
Tesng code that cells external modules poses several problems:
1. If we find a bug, is it in our module, or the calling module?
2. If we want to rigorously verify the behaviour of the system, the outputs include the side
effects.
3. The outside world can be unpredictable, making it hard to repeat tests
4. You don’t want a system under test interacng with writable, valuable data
5. Wring and reading from the outside world can pose performance problems
Glue code
Code that replaces objects, modules and methods outside of the unit order test
●Stubs : empty methods that did nothing but return appropriate dummy data
●Fakes: More comprehensive but limited prototype implementaons for tesng that can do
things like check arguments and apply simple logic to determine an appropriate test data
●Shim: Intermediate code inserted to check arguments before handing off to the real
exenteral code that did the work
Document Summary
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